Laboratory Animal Science Past Paper 2020-2021 PDF
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This document contains answered questions from a 2020-2021 Laboratory Animal Science exam. Topics covered include the Three Rs, postmortem examinations, and various aspects of laboratory animal care. It includes detailed explanations about the questions.
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Laboratory Animal Science Laboratory Animal Science Answers LAS exam Questions ANSWERS LAS EXAM QUESTIONS ACADEMIC YEAR:2020-2021 NAME STUDENTS: COURSE: ADVANCED PLANT CELL BIOLOGY AND SIGNALING | MASTER BIOMEDICAL AND PLANT BIOTECHNOLOGY Reports sensory phys...
Laboratory Animal Science Laboratory Animal Science Answers LAS exam Questions ANSWERS LAS EXAM QUESTIONS ACADEMIC YEAR:2020-2021 NAME STUDENTS: COURSE: ADVANCED PLANT CELL BIOLOGY AND SIGNALING | MASTER BIOMEDICAL AND PLANT BIOTECHNOLOGY Reports sensory physiology online stimulation lab 0 Laboratory Animal Science 0. CONTENT 0. Content..........................................................................................................................................................................1 1. Introduction in laboratory animal science (Prof. dr. K. Hermans).............................................................................2 2. Postmortem examination (Prof. dr. K. Hermans).......................................................................................................3 3. Embryology (Prof. dr. P. Cornillie)................................................................................................................................5 4. Diseases and disease control (Prof. dr. K. Hermans)............................................................................................... 15 5. Taxonomy (Prof. dr. P. Cornillie)............................................................................................................................... 21 6. Reproduction and reproductive techniques (Prof. dr. A. Van Soom)..................................................................... 25 7. Comparative morphology (Prof. dr. W. De Spiegelaere)......................................................................................... 31 8. Principles of surgery in experimental animals (Prof. dr. A. Martens).................................................................... 39 9. Nutrition of laboratory animals (Prof. dr. G. Janssens)........................................................................................... 44 10. Basic principles of pharmacokinetics and pharmacodynamics (Prof. dr. M. Devreese).................................. 49 11. Comparative physiology (Drs. C. De Meeûs)....................................................................................................... 53 12. Immunology (Prof. dr. E. Cox)............................................................................................................................... 57 13. Postoperative care (Prof. dr. K. Hermans)........................................................................................................... 63 14. Experimental techniques (Prof. dr. K. Hermans)................................................................................................. 69 15. Chapter 15: Medical Imaging................................................................................................................................ 69 16. Chapter 16: Radiobiology and radioprotection................................................................................................... 73 17. Chapter 17: Analgesia and anaesthesia............................................................................................................... 75 18. Chapter 18: Laboratory animal legislation........................................................................................................... 78 19. Chapter 19: Ethical committees........................................................................................................................... 79 20. 20. Ethology & stress : Animal welfare................................................................................................................ 85 21. Chapter 21: Housing.............................................................................................................................................. 90 22. Chapter 22: Environmental enrichment.............................................................................................................. 92 23. Chapter 23: Statistics............................................................................................................................................. 94 24. Topic 24: Extrapolation of experimental data to man........................................................................................ 98 25. TOPIC 25: The ethics of animal use.................................................................................................................... 100 26. TOPIC 26: Safety in working with laboratory animals....................................................................................... 102 27. TOPIC 27: viral zoonoses..................................................................................................................................... 104 28. TOPIC 28: Bacterial zoonoses............................................................................................................................. 106 29. TOPIC 29: Euthanasia of laboratory animals..................................................................................................... 108 Answers LAS exam Questions 1 Laboratory Animal Science 30. TOPIC 30: Transportation of laboratory animals............................................................................................... 111 31. Disease prevention & hygiëne............................................................................................................................ 112 32. GLP........................................................................................................................................................................ 115 33. 34a. Genetics....................................................................................................................................................... 120 EXAMENVOORBEREIDING LAS H1-14 1. INTRODUCTION IN LABORATORY ANIMAL SCIENCE (PROF. DR. K. HERMANS) 1.1. WHAT ARE THE 3RS? EXPLAIN AND GIVE AN EXAMPLE OF EACH. The Three Rs (3Rs) are guiding principles for more ethical use of animals in testing. They were first described by Russell and Burch in 1959. The 3Rs are Replacement, Reduction and Refinement. Replacement: methods which avoid or replace the use of animals in research: In vitro models like human multilayered corneal cell model for toxicity studies Computerized models, videos and film Reduction: use of methods that enable researchers to obtain comparable levels of information from fewer animals, or to obtain more information from the same number of animals. Animal sharing: Within an institution Surgery practice on an animal euthanized for other purposes Improved statistical design: Well designed experiments Appropriate statistical methods Better quality animals: So there would be no animal loss And no intercurrent diseases (data will be less compromized) Refinement: use of methods that alleviate or minimize potential pain, suffering or distress, and enhance animal welfare for the animals used. Should be applied at any stage Better techniques, equipment Might make it possible to use smaller sample sizes => e.g. no euthanasia needed Right handling of animals Proper handling must be part of the regular routine Housing of animals Environmental enrichment Anelgesia 1.2. NON TECHNICAL SUMMARY (NTS): VOOR WIE DIENT DIT? Meant to inform the general public about benefits of the project, how many animals will be needed and how they are treated Answers LAS exam Questions 2 Laboratory Animal Science some extra info from slides: how to write a NTS: Make sure the general public understands - e.g. television news aims at level of 13-14 year-olds - imagine a person (not familiar with lab animal experiments or science in general) for who you write this (e.g. your mother or your neighbour) - Title = take home message (without details) - Avoid jargon - Also provide “the big picture” - Do not try to minimize the impact on the animals but: o make your goal clear o explain why alternatives cannot be used o explain how you minimize the discomfort for the animals - In Flanders: obligatory in Dutch - General public should understand 1.3. GIVE DIFFERENT FELASA CATEGORIES - Category A= person taking care of animals - Category B= people carrying out laboratory animal experiments - Category C: person responsible for directing animal experiments (this course) - Category D: Laboratory animal science specialist 2. POSTMORTEM EXAMINATION (PROF. DR. K. HERMANS) 2.1. DISCUSS THE CONSERVATION AND SHIPMENT OF SAMPLES AFTER NECROPSY Conservation and sending of samples: Complete history should be included Age, breed and sex should be mentioned Everything should be clearly labelled/ in separate plastic bag Fresh tissues Packed individually In leakproof containers or plastic bags In Surrounded by ice packs Fecal specimens Should be kept cool in transit Unclotted blood samples Should be sent cooled, not frozen Serum Should be poured off the clot Should be sent cooled or frozen Formalin-fixed tissues No more than 1cm thick Placed in wide-mouth leak-proof container 10 times the volume of formalin to tissue 2.2. FORMALIN-FIXED TISSUES, WHAT IS IMPORTANT IN PRESERVATION? Use 10% neutral buffered formalin Use 10x more fixative than tissue Answers LAS exam Questions 3 Laboratory Animal Science Use tissues not more than 1cm think -> otherwise the formalin will not reach the centre of the tissue quickly enough and this will autolyse before fixation If using larger tissues -> sectioning required (= cut into pieces) 2.3. WHAT IS NECROPSY? Necropsy = autopsie, uitvoeren van een onderzoek op reeds dood proefdier a post-mortem examination to discover the cause of death or the extent of disease. 2.4. HOW CAN AUTOPSY BE USEFUL/NECESSARY? Might be necessary for the experiment itself: In drug evaluation studies In pathogenesis studies To study the effect of the experiment (treatment, drug, …) Is necessary for laboratory animal welfare Necropsy should be performed on every unexpectedly dead animal to find the cause of death Purpose: Disease monitoring Problems with housing/care: Fighting, faulty cage design, faulty water supply Stress? Check for Gastrointestinal ulcers (stress !) Problems related to the experiment itself Did the administered drug kill the animal? 2.5. POST-MORTEM EXAMINATION STEPS : 1. External examination o (check whether everything is normal, after cutting, you cannot know whether abnormality was already there of was due to cutting of the animal) 2. Macroscopic evaluation of organs - Opening and Examination of abdominal cavity o Liver, gall bladder, GI-tract, spleen, pancreas) o Genital organs, urinary bladder o kidneys, adrenal glands o Lymph nodes and mammary tissue - Opening and examination of Nasal and oral cavity (teeth) - Opening of thorax o Oesophagus o thyroids (=’schildklieren’) o thymus o mediastinal lymphnodes o lungs o heart) o Removal and inspection of the brain 3. After macroscopic evaluation of organs Direct microscopy of gut content (immediate result) – Cytology (immediate result) – Histology (several days) – Bacteriology (several days) – Virology (week(s) if isolation) Answers LAS exam Questions 4 Laboratory Animal Science – Toxicology (depends, minimum several days) 3. EMBRYOLOGY (PROF. DR. P. CORNILLIE) 2 vragen die vaak terugkomen: placenta vraag en organogenesis/critical period. Tijdens de lecture opname zei hi specifiek dat hij placentatievraag ging stellen. 3.1. DISCUSS THE SPECIES-SPECIFIC DIFFERENCES Prenatal development if quite different in the various species of laboratory animals. These differences makes comparing intraspecial embryotoxicity and teratogenicity hard. Kzou dit skippen, ging wss ook over placentas die vraag 3.2. DISCUSS THE CRITICAL PERIOD OF ORGANOGENESIS Critical period: Specific time window during which a certain organ (structure/tissue/anatomical configuration) is most susceptible to the influence of teratogens (term): Different for each organ or structure Embryonic period = most vulnerable for malformations = organogenesis including Critical period most often falls within embryonic period o Teratogens before embryonic period: often embryonic death o Teratogens in fetal perios: may still interfere with maturation of certain organs o Embryonic period = Period form axis formation until the appearance of species-specific characteristics Teratogen: Any factor potentially leading to malformations (term): Teratogens are substances which can cause malformations. Their toxicity is highest for specific organs/structures during their so-called “critical period”. It is an interval in which the structure is rapidly developing, or rearranging in a way, which makes it highly susceptible for disruption. It is different for every organ/structure, but it is usually highest at the initial stage of development. Anlage: the rudimentary basis of a particular organ or other part, especially in an embryo. Example: The critical period for limb development ranges from weeks 4-7 in man, weeks 4-6 in the cat, weeks 3-4 in the dog and weeks 2-3 in the rabbit and rat. During organogenesis, exogenous teratogenic agents have the greatest disruptive impact on prenatal development as during the period in which an organ is being established (i.e., when obligatory inductive tissue interactions and morphogenesis occur), this meticulous developmental pattern is highly susceptible to any interfering agent and easily disturbed. Before the period of organogenesis, noxious entities will mostly induce embryonic death, whilst during the fetal period teratogens will interfere with the maturation of certain organs e.g. brains, causing in this example for instance mental retardation. The period in which the primordium of a certain organ develops is therefore called the critical period of that organ. As the organs do not develop all at the same time, the critical period of every organ will be different and the effect of an exogenous teratogen will depend on the specific time of interaction: Examples: Answers LAS exam Questions 5 Laboratory Animal Science - A pteroylglutaminacid-deficient diet fed to pregnant rats will induce brain and cardiac malformations when supplied at days 7-9, lesions in the skeletal, urinary and vascular systems at days 9-11 and skeletal lesions only when given at days 11-14 of pregnancy. - Thalidomide intake by pregnant women between 34 and 38 days after the last menstruation caused absence of the ears, absence of the thumbs between 38 and 42 days, absence of the arms between 38 and 43 days, severe shortness of the arms between 38 and 47 days, dislocation of the hip between 38 and 48 days, malformation of the ear between 39 and 43 days, absence of the legs between 41 and 45 days, severe shortness of the legs between 42 and 47 days and malformed thumbs between 46 and 50 days after last menstruation. The critical period for a certain organ system is also very species-specific: - The critical period for limb development ranges from weeks 4-7 in man, weeks 4-6 in the cat, weeks 3-4 in the dog and weeks 2-3 in the rabbit and rat. 3.3. COMPARE PLACENTATION OF MAN, RODENT AND NON-RODENT SPECIES OF CHOICE o Know them for man o Know them for a rodent and a non rodent species of choice o Will ask on the examination to compare species and discuss 5 items (of choice) of these terms (uit die tabel) o Alle termen die je gebruikt kunnen uitleggen o Explain what is different, what is similar and why that is. o Explanation: lecture video 2:40 o Tabel voor wie muis/mens/varken beschrijft zoals ik NIET ALLE INFORMATIE OVER PLACENTAS die hieronder staat is te kennen, Kies je 3 species en bereid een antwoord voor adhv tabellen hierboven en de info hieronder Answers LAS exam Questions 6 Laboratory Animal Science 3.3.1. U ITGESCHRE V E N A NTW O O RD - Implantation o Mouse: eccentric Eccentric implantation: the conceptus develops between two endometrial folds: mouse, rat, gerbil. (With the development of the chorioallantoic placenta (in addition to the inverted vitelline placenta), the implantation type in these species changes from eccentric to interstitial). o Human: interstitial Interstitial implantation or nidation: the conceptus is embedded within the uterine wall (invasion of the subendometrial stroma after phplaagocytosis of the endometrium by the trophoblast) without making further contact with the uterine lumen: o Pig: central/ superficial Central or superficial implantation: the conceptus remains in the uterine lumen throughout the gestational period: - Amniogenesis o mouse: Cavitation and plectamnion Plectamnion: the amnion arises as folds of the trophoblast tissue enclosing the region above the prospective embryo. o human shizamnion Schizamnion: the primitive amniotic cavity arises as a cleft that separates the inner cell mass into the prospective embryo and amnion itself: o pig: plectamnion Answers LAS exam Questions 7 Laboratory Animal Science - Extra info: o In mammals, birds and reptiles (all belonging to the amniotes), the embryo or fetus lies within the fluid-filled amniotic cavity surrounded by the amnion. Two major types of amniogenesis (formation of the amnion) are described: ·Schizamnion and plectamnion o Plectamnion: the amnion arises as folds of the trophoblast tissue enclosing the region above the prospective embryo. Prior to this folding, the prospective embryo must be separated from the overlying trophoblast in three possible ways: In rodents (except the hamster and guinea pig), the inner cell mass first hollows (pro- amniotic cavity). Subsequent folding of the trophoblast subdivides this cavity in an upper ectoplacental cavity, a lower amniotic cavity (dorsal to the presumptive embryo) and in the middle the extraembryonic coelom (exocoelom). The basic function of the fluid-filled amnion is to provide the developing embryo with protection against desiccation and with a milieu for flotation in which it can grow without distortion by pressure from surrounding structures. Ungulates/carnivores and rabbits niet van toepassing hier - Placental barrier o Mouse: hemotrichorial o Human: hemomonochorial Hemochorial: The maternal endothelium is also lost and the chorion is directly bathing in the circulating maternal blood. This type is further subdivided according to the number of cell layers of the trophoblast (chorionic epithelium): Hemomonochorial: 1 Hemodichorial: ra2bbit Hemotrichorial: 3 o Pig: epitheliochorial this is the typical configuration in a totally non-invasive placenta: six layers of tissue exists between maternal and fetal circulation: maternal capillary endothelium, endometrial stroma (connective tissue), uterine epithelium, chorionic epithelium (trophoblast), fetal connective tissue and fetal endothelium respectively. o Extra info: The placental barrier is defined by the number of tissue layers that nutrients have to cross from the lumen of the maternal vessels to the lumen of the fetal capillaries at the level of the hemotrophic chorioallantoic placenta, evaluated in the later stages of gestation. This classification is commonly called the Grosser classification (refined by Ender). To correctly determine the placenta barrier type, tissue layers between exactly opposed fetal and maternal capillaries should be counted. For instance, the trophoblast in the human placenta is composed of two layers: a basal cytotrophoblast layer and an external syncytiotrophoblast. However, the cytotrophoblast layer is discontinuous and does not intervene between the fetal capillaries and syncytiotrophoblast. As a consequence, the human placenta type is haemomonochorial instead of haemodichorial. Maternal immunoglobulines, essential for the survival of the newborn (protection against infections), can only sufficiently pass hemochorial placenta. In animals with a epitheliochorial placenta, immonuglobulines are transferred in the first hours after birth to the newborn by means of the colostrum (first milk). In animals with an Answers LAS exam Questions 8 Laboratory Animal Science endotheliochorial placenta, a combination of both types of passive immune transfer is used. - Chorionic surface o Mouse: labyrinthine More advanced form of the villous placenta in which the tips of neighbouring villi fuse, forming a complex network o Human: villous Tree-like projections of the chorion with a cone-shaped or tubular stem from which several branches sprout: o Pig: villous, but actually rugae These are folds that compromise all tissue layers of the allantochorion and which interdigitate with folds of the maternal endometrium (typical in the pig o Extra ingo van mail prof: When it comes to classification (handbooks), one generally recognizes villous & labyrinthine types of placenta. The former is the more simple form, the latter is a complex network. As such, pigs can be regarded as having a villous placenta. But the vast majority of the porcine placental surface does not contain true villi, but rugae. Rugae are accordion-like interdigitating folds, so interlocking surface rims, whilst villi are tree-like branching projections with a central stem. Villi in the pig placenta only occur at the site of the areolae, where there is local detachment of the fetomaternal interface, and tree-like chorionic projections float in the secretions of the maternal glands. o Microvilli, the surface extension of an individual cell (true microscopic to ultramicroscopic level) do occur in all types of placentae, except the endotheliochorial one seen in carnivores. Apparently, fetal cells encircling maternal vessels do not form microvilli. - Paraplacental structures o Mouse: none o Human: none o Pig: areolae Areolae are domes of trophoblast covering local areas of the endometrium characterized by an increased glandular activity. The chorionic villi in the areolae are numerous and highly branched and float in the space between the chorion and endometrium. Areolae serve as a site of histiotrophic nutrition and have an important role in transfer of iron. o Extra info: Paraplacental structures are distinct anatomically identifiable structures apart from the actual placenta, with several possible functions such as histiotrophic nutrition, production of hormones, erythrocytophagocytosis,… but never hemotrophic nutrition. An interaction between maternal and fetal tissues is always present. Examples include: Areolae, marginal hematomes, endometrial cups, and subplacenta Alles info over placenta’s hieronden kan je gebruiken om je eigen antwoord op te stellen, je kan ook het bovenstaande overnmen Answers LAS exam Questions 9 Laboratory Animal Science 3.3.2. P L A CENTA S CA N BE CL A SSIFIED BA SED O N (8): o Shape o Surface morphology of the chorion o Placental barrier and endometrial invasion o Trophoblast cytology o Fate of the maternal endometrium o Composing fetal membranes & vasculature o Paraplacental structures o (Implantation types) 3.3.3. P L A CENTA L CL A SSIFICA TIO N BA SED O N SHA PE , GIVE THE DIFFEREN T TYPES + EXA MPL E FO R EA CH Shape - chorioallantoic placenta shape at the end of gestation: Diffuse: the entire allantochorion participates in the feto-maternal exchange Complete diffuse: horse Incomplete diffuse: Pig: the stretched chorion contains necrotizing avascular tips Zonary: girdle-like placenta Complete zonary: carnivores: Cat, dog, … Incomplete zonary: mustelids (marterachtigen)(ferret, mink, raccoon) Cotyledonary: the area of hemotrophic nutrition is restricted to several discrete sites Sites on the allantochorion called cotyledons, which are opposed to the maternal uterine caruncles. The combination of a caruncle and cotyledon is called a placentome. ruminants polycotyledonary: catle, sheep, goats: 80-160 placentomes oligocotyledonary: deer: 3-12 placentomes Discoid: a disc-like placenta Discoid: man, apes, rodents, rabbit: one single placental disc. In the rabbit, a large groove on the fetal side subdivides the discoid placenta into two lobes. Bidiscoid: monkeys: in 80% of the pregnancies, two placental discs are formed: one disc on each mesometrial side of the uterus due to the central implantation of the embryo (compared to the interstitial implantation in the apes and human). 3.3.4. P L A CENTA L CL A SSIFICA TIO N BA SED ON S URFA CE MO RPHO L O GY O F THE CHO RIO N , GIVE THE DIFFERENT TYPES + EXA MPL E FO R EA CH In all placenta types, extension of the useful surface is essential to ensure a sufficient feto-maternal exchange area. o Microvilli: This surface extension starts very discrete with the appearance of microvilli on the trophoblast cells. These microvilli interdigitate with microvilli on the endometrial epithelial cells. The microvilli on the trophoblast remain present even in invasive placentae (see placental barrier), except in the endotheliochorial placenta type. o Rugae: These are folds that compromise all tissue layers of the allantochorion and which interdigitate with folds of the maternal endometrium (typical in the pig). ??? o Villi: Tree-like projections of the chorion with a cone-shaped or tubular stem from which several branches sprout: o domestic ungulates, monkeys and man. o Labyrinth: More advanced form of the villous placenta in which the tips of neighbouring villi fuse, forming a complex network: o carnivores, rodents, apes and the rabbit. 3.3.5. P L A CENTA L CL A SSIFICA TIO N BA SED O N P L A CENTA L BA RRIER A ND ENDO METRIA L INVA SIO N , GIVE THE DIFFERENT TYPES + EXA MPL E FO R EA CH Answers LAS exam Questions 10 Laboratory Animal Science The placental barrier is defined by the number of tissue layers that nutrients have to cross from the lumen of the maternal vessels to the lumen of the fetal capillaries at the level of the hemotrophic chorioallantoic placenta, evaluated in the later stages of gestation. This classification is commonly called the Grosser classification (refined by Ender). To correctly determine the placenta barrier type, tissue layers between exactly opposed fetal and maternal capillaries should be counted. For instance, the trophoblast in the human placenta is composed of two layers: a basal cytotrophoblast layer and an external syncytiotrophoblast. However, the cytotrophoblast layer is discontinuous and does not intervene between the fetal capillaries and syncytiotrophoblast. As a consequence, the human placenta type is haemomonochorial instead of haemodichorial. Epitheliochorial: this is the typical configuration in a totally non-invasive placenta: six layers of tissue exists between maternal and fetal circulation: maternal capillary endothelium, endometrial stroma (connective tissue), uterine epithelium, chorionic epithelium (trophoblast), fetal connective tissue and fetal endothelium respectively. This type of placental barrier is present in the pig and horse. In the pig, both the maternal and fetal capillaries move towards their overlying epithelium and even appear to nestle themselves between the epithelial cells. This specific phenomenon has lead to the suggestion that the placenta type in pigs might be endothelioendothelial, but electron microscopic studies have confirmed that the six aforementioned layers remain enduringly present. Synepitheliochorial: The trofoblast and uterine epithelium are partially or totally fused, and are characterised by the presence of numerous giant cells (cattle) and a large syncytium (sheep & goat). Endotheliochorial: The uterine epithelium and stroma are eroded away by the invasive trophoblast. The trophoblast is apposed to the (thickened) endothelium of the maternal vessels (cat, dog and most other carnivores except the hyena). Hemochorial: The maternal endothelium is also lost and the chorion is directly bathing in the circulating maternal blood. This type is further subdivided according to the number of cell layers of the trophoblast (chorionic epithelium): Hemomonochorial: man, guinea pig Hemodichorial: rabbit Hemotrichorial: mouse, rat, hamster Maternal immunoglobulines, essential for the survival of the newborn (protection against infections), can only sufficiently pass hemochorial placenta. In animals with a epitheliochorial placenta, immonuglobulines are transferred in the first hours after birth to the newborn by means of the colostrum (first milk). In animals with an endotheliochorial placenta, a combination of both types of passive immune transfer is used. 3.3.6. P L A CENTA L CL A SSIFICA TIO N BA SED O N T RO PHO BL A ST CYTO L O GY , GIVE THE DIFFERENT TYPES + EXA MPL E FO R EA CH o Initially, the trophoblast is a single layer of individual cells (cytotrophoblast). In the non-invasive placentae of the ungulates, this condition is maintained until parturition. o In some placentae, the cytotrophoblast is gradually replaced by a syncytiotrophoblast: a multinucleated cell aggregate: the individual cell boundaries are lost, resulting in a syncytium (carnivores, guinea pig). o In rabbits and man, the trophoblast layer is doubled. In the rabbit, the internal layer develops into a syncytiotrophoblast whilst the outer layer remains a cytotrophoblast. The opposite is true in the human. As mentioned before, the internal cytotrophoblast layer (Langhan’s cells) in man is discontinuous. o In the rat and mouse, the trophoblast is composed of three layers, of which the inner and middle one each form a syncytium. The outer trofoblast layer remains a cytotrophoblast. Answers LAS exam Questions 11 Laboratory Animal Science The exact reasons why a syncytiotrophoblast is built are largely unresolved. It is supposed that it helps in preventing the rejection of the fetus (which can be considered as a semi-allograft) by the maternal immune system as the absence of cell bounderies prevents lymphocytes from crawling through the intercellular space (diapedesis) and migrating towards the fetus. Giant cells: are a special types of trophoblast cells (although they are sometimes confusingly called decidua cells) characterized by their large volume. They are described in the placenta of man, rodents, ruminants and the cat, and the endometrial cup cells of the horse can also be regarded as giant cells. They are highly invasive: even in ruminants and the horse which normally have a non-invasive trophoblast, giant cells are invading the endometrial epithelium. They most often contain two or more nuclei as a result of cell fusion (trophoblast x maternal epithelial cell) or duplication of the nucleus without cytodieresis. Although the function of giant cells in the cat is unknown, endocrine functions have been ascribed to human, ruminant and equine giant cells: production of Human Chorionic Gonadotropin & Human Placental Lactogen, Pregnancy Associated Glycoproteins and Equine Chorionic Gonadotropin respectively. In rodents, wandering giant cells help the embryo invading in the endometrium and establish the hemochorial placenta type by breaking the maternal vascular walls. 3.3.7. P L A CENTA L CL A SSIFICA TIO N BA SED O N THE FA TE O F THE MA TERNA L ENDO METR IU M , GIVE THE DIFFERENT TYPES + EXA MPL E FO R EA CH o Adeciduate placenta: At birth, the fetal side of the placenta detaches from the maternal side (placenta apposita or semiplacenta): the afterbirth is delivered without endometrial loss. The maternal side of the placenta regresses in the uterus. This is typical for the epitheliochorial placentae of the ungulates. o Deciduate placenta: This placenta type is characterized by the deep invasion of fetal tissues in the endometrium. Due to this intimate contact, a substantial amount of the maternal tissue (decidua) is shed after birth together with the fetal membranes and fetal part of the placenta, resulting in an endometrial wound. As these types of placentae are relative small (discoid or zonary placenta), this wound heals fast. Deciduate placentae are present in rodents, the rabbit, carnivores and primates. In species with an interstitial implantation (man, apes & guinea pig), the decidua is given different names depending on its relative position to the embryo within its fetal membranes: o Decidua basalis: the portion of the decidua directly underlying the embryo and attached to the myometrium o Decidua reflexa or decidua capsularis: the portion of the decidua directly overlying the embryo and facing the uterine cavity o Decidua parietalis: the portion of the decidua lining the uterus elsewhere than at the site of attachment of the embryo o Contradeciduate placenta: Both the maternal and fetal parts of the placenta remain in the uterus after birth where they are slowly resorbed. This type of placenta is said to occur in the mole and certain marsupials. 3.3.8. P L A CENTA L CL A SSIFICA TIO N BA SED O N CO MPO SING FETA L MEMBRA NES A ND VA SCUL A TURE , GIVE THE DIFFERENT TYPES + EXA MPL E FO R EA CH o Chorioallantoic placenta & umbilical circulation. o As mentioned earlier, this is the most important type of placentation in all eutherian mammals. In ruminants and the pig, the allantois does not fuse with the entire inner surface of the chorion: dorsal to the embryo, the amnion is lying in direct contact with the chorion. However, this chorioamniotic area is invaded with umbilical (allantoic) vessels and therefore does not form a separate entity. Answers LAS exam Questions 12 Laboratory Animal Science o Choriovitelline placenta & vitelline circulation. This type of placenta is present in the horse and carnivores. Although it is in later stages of development dominated by the chorioallantoic placenta, it remains functional until term. It is also present in the early stages of rabbit development, but is afterwards replaced by the inverted yolk sac placenta. o Inverted yolk sac placenta and vitelline circulation. This is present in the rabbit and rodents (see inversion of the vitelline sac above). 3.3.9. P L A CENTA L CL A SSIFICA TIO N BA SED O N PA RA PL A CENTA L STRUCTURE S , GIVE THE DIFFERENT TYPES + EXA MPL E FO R EA CH Paraplacental structures are distinct anatomically identifiable structures apart from the actual placenta, with several possible functions such as histiotrophic nutrition, production of hormones, erythrocytophagocytosis,… but never hemotrophic nutrition. An interaction between maternal and fetal tissues is always present. o Areolae are domes of trophoblast covering local areas of the endometrium characterized by an increased glandular activity. The chorionic villi in the areolae are numerous and highly branched and float in the space between the chorion and endometrium. Areolae serve as a site of histiotrophic nutrition and have an important role in transfer of iron. o Although they are described in many ungulates, cetaceans (whales & dolphins) and insectivores, they are a typical feature of the pig placenta. o These numerous circular structures of approximately 2-4 mm in diameter are scattered all over the chorionic surface. o Areola-like structures in other species than those mentioned above (e.g. carnivores) are sometimes called chorionic vesicles. o Marginal hematomes are a characteristic of the zonary placenta of carnivores. In this area, extravasation of maternal blood occurs, allowing erythrocytophagocytosis by the trophoblast cells. This area is therefore important for iron transfer. Due to the local metabolisation of hemoglobin in the marginal hematomes of the dog, these borders adopt a green color. In the cat, the hematomes are very narrow and have a brownish color. In the incomplete zonary placenta of the mink and ferret, hematomes are located centrally. o Subplacenta: This is a characteristic feature of caviomorph rodents (guinea pig), although it is also described in other rodent species as a very rudimentary structure. The subplacenta is an accessory placenta-like structure beneath the central part of the actual placenta consisting of a separate labyrinth with trophoblastic projections into the underlying decidua. Because of its most basal location, it is the first structure that is supplied by maternal blood vessels. However, before the subplacenta is reached by the umbilical circulation of the fetus, the circulation in the maternal lacunae ceases and blood clot formation occurs. Therefore, the subplacenta of the guinea pig does not contribute in the hemotrophic feto-maternal exchange. The functional importance of the subplacenta is still a mystery. Some believe that because of its deep invasion in the endometrium, it ensures a firm attachment of the conceptus to the uterus. By its degeneration 14 days before birth, it could also help to minimize the endometrial wound after delivery. Some trophoblast cells of the subplacenta penetrate through the entire uterine wall and enter the maternal peritoneal cavity where they will replace the mesothelial cells (cells that line the peritoneal cavity). These migrated trophoblast cells produce nitric oxide, which has a vasodilatory effect on the mesometrial and uteroplacental arteries. These cells die within 5 days after delivery. o Endometrial cups: at the level of the chorionic girdle in the horse, trophoblast cells migrate towards, and invade the endometrium where they will form clusters (cups) of giant endocrinal cells producing eCG (formerly called PMSG). These endometrial cups are subsequently rejected by a maternal immunological reaction. The endometrial cups are therefore transitional structures, actively present from day 38 till 100 of gestation and are completely rejected at day Answers LAS exam Questions 13 Laboratory Animal Science 150. Their primary function is to induce new ovulations in the mare’s ovaries with subsequent formation of secondary corpora lutea as a new source of progesterone to maintain the pregnancy after degeneration of the first corpus luteum which is formed after ovulation of the oocyte that lead to pregnancy. 3.3.10. CL A SSIFICA TIO N BA SED O N I MPL A NTA TIO N TYPES , GIVE THE DIFFEREN T TYPES + EXA MPL E FO R EA CH Implantation refers to the attachment of the developing embryo to the uterine wall and the establishment of a permanent link between the embryo and the mother, which will result in the formation of a placenta. From the moment of arrival in the uterus until the moment of implantation, the embryo can move freely inside the uterus and can be flushed out of it (see course of artificial reproduction techniques). In horses, The ability to move inside the uterus is vital for the recognition of pregnancy by the mare: the horse embryo wanders, until the moment of implantation, up en down from one uterine horn to the other to “notify” the mare of its presence. In multiparous animals, this freedom of movement enables the embryos to position themselves at a relatively equal distance from their neighbouring siblings along the entire length of the uterine horns. Implantation is usually classified according to the depth of penetration of the embryo in the uterine wall: o Central or superficial implantation: the conceptus remains in the uterine lumen throughout the gestational period: ungulates, carnivores, rabbit, monkeys (tailed anthropoids). o Eccentric implantation: the conceptus develops between two endometrial folds: mouse, rat, gerbil. (With the development of the chorioallantoic placenta (in addition to the inverted vitelline placenta), the implantation type in these species changes from eccentric to interstitial). o Interstitial implantation or nidation: the conceptus is embedded within the uterine wall (invasion of the subendometrial stroma after phagocytosis of the endometrium by the trophoblast) without making further contact with the uterine lumen: man, apes (tailless anthropoids), guinea pig & hamster. 3.3.11. A MNIO GENES IS In mammals, birds and reptiles (all belonging to the amniotes), the embryo or fetus lies within the fluid-filled amniotic cavity surrounded by the amnion. Two major types of amniogenesis (formation of the amnion) are described: · - Schizamnion: the primitive amniotic cavity arises as a cleft that separates the inner cell mass into the prospective embryo and amnion itself: primates incl. man, guinea pig, hamster - Plectamnion: the amnion arises as folds of the trophoblast tissue enclosing the region above the prospective embryo. Prior to this folding, the prospective embryo must be separated from the overlying trophoblast in three possible ways: o In carnivores and the rabbit, the early trophoblast overlying the inner cell mass disappears and the inner cell mass flattens out at the surface of the blastocyst. o In ungulates, the inner cell mass first hollows (embryocyst). Then the roof of this embryocyst ruptures and disappears together with the overlying trophoblast. o In rodents (except the hamster and guinea pig), the inner cell mass first hollows (pro- amniotic cavity). Subsequent folding of the trophoblast subdivides this cavity in an upper ectoplacental Answers LAS exam Questions 14 Laboratory Animal Science cavity, a lower amniotic cavity (dorsal to the presumptive embryo) and in the middle the extraembryonic coelom (exocoelom). The basic function of the fluid-filled amnion is to provide the developing embryo with protection against desiccation and with a milieu for flotation in which it can grow without distortion by pressure from surrounding structures. 4. DISEASES AND DISEASE CONTROL (PROF. DR. K. HERMANS) 4.1. WHAT IS THE IMPACT OF DISEASE ON YOUR EXPERIMENTAL RESULTS (ALSO SUBCLINICAL CARRIERS)? During the experiment : Bad for animal well-fare Can cause mortality and morbidity Animal as subclinical carrier (= You don’t see any symptoms, but disease can be transmitted to other animals) o -> These carriers have to be placed in quarantine o “subclinical” but can still have influence on biological parameters of the lab animal : -> Can have influence on results if these are the outcomes of your experiment o Behaviour o Body weight o Feed & water uptake o Blood values o Immune response Can influence biological parameters => and thus experimental results Importance on experimental results : Is the outcome due to the experiment or due to the disease? Possible to take the wrong conclusions Importance on animal well-fare : Well-fare of the animal can have influence on the results Importance on zoonoses = transmission of diseases from animals to human 4.2. EPIZOOTIC, EXPLAIN IN 1-2 SENTENCES (SIMILARLY: ENZOOTIC) Epizootic = infection that appears as new cases in a given animal population, during a given period, at a rate that substantially exceeds what is "expected" based on recent experience (cf Epidemic) (term): Enzootic = infection maintained in the population without need for external inputs (cf Endemic) (term): 4.3. QUARANTAINE, EXPLAIN IN 1-2 SENTENCES Quarantine = Separation/ Putting apart of animals ( to avoid spread of pathogens) - During incubation period = period between pathogenic agent entering the body and the first clinical sign of the disease -> These agent can already be spreading in this period -> Uncertainty of recently bought animals whether or not in incubation period o -> Put in quarantine Answers LAS exam Questions 15 Laboratory Animal Science - When subclinical carrier = you don’t see any symptoms, but disease can be transmitted to other animals 4.4. SUBCLINICAL CARRIER, EXPLAIN IN 1-2 SENTENCES carrier of a disease which does not show noticable (clinical) signs or symptoms 4.5. INCUBATION PERIOD, EXPLAIN IN 1-2 SENTENCES time elapsed between exposure to a pathogenic organism, (or a chemical, or radiation), and when symptoms and signs are first apparent 4.6. FACULTATIVE PATHOGEN, EXPLAIN IN 1-2 SENTENCES Pathogen that only causes disease if some 'pre-disposing' factor is present, e.g. wound, stress,... Opposed to abligate/obligatory pathogen: Pathogen that always causes disease (no need for pre-disposing factor) 4.7. WHICH FORMS OF DISEASE ARE CAUSED BY PASTEURELLA MULTICODA IN RABBITS? o * Which forms of disease are caused by Pasteurella multicoda in rabbits? Niet gezien in les maar: PPT foto’s: Exophtalmia due to retrobulbar abscess (Pasteurella multocida infection) Conjunctivitis (due to Pasteurella infection) Rhinitis (due to Pasteurella infection) Antwoorden vorige Jaren: - Exophtalmia = protruding eyeball -> due to abscess - Conjunctivitis = lacrimation = eye discharge - Rhinitis = nasal discharge Pasteurellosis is a bacterial disease that can be a cause of: - nasal (=rhinitis) or sinus infections, - ear or eye infections (= conjunctivitis), - pneumonia - abscesses in bone, joints, - tilting head (=torticollis) or internal organs in rabbits. Answers LAS exam Questions 16 Laboratory Animal Science Pasteurella colonizes the nasal cavity and upper respiratory tract, but many rabbits do not show symptoms as long as the immune system is functioning normally (=facultative pathogen). Most infections begin in the nose. Infection may then spread into the sinuses and bones of the face and/or spread via the eustachian tubes to the ears, via the nasolacrimal duct to the eye, via the trachea to the lower respiratory tract, and via the bloodstream to joints, bones, and other organ systems. 4.8. WHAT HAPPENS IF NO VIT C IS PROVIDED IN THE FOOD OR DRINKING WATER OR GUINEA PIGS? What happens if no vit C is provided in the food or drinking water of guinea pigs? Kwam ook niet voor in les: Vorige examens: Bleedings, skin lesions, inflammation, retardation, problems with wound healing doc: Vit C = Ascorbinezuur. Tekort zorgt voor een gebrekkige collageensynthese. Het is ook nodig in het spiermetabolisme. Een tekort is zichtbaar in slapte, bloederig tandvlees, interne bloedingen, spierzwakte, bloedingen in spieren, bloedarmoede,... (bloedingen in de pootjes) bloedingen scurvy = scheurbuik 4.9. SYMPTOMS AND LESIONS AFTER MYCOPLASMA INFECTIONS IN MICE AND RATS * Symptoms and lesions after Mycoplasma infections in mice and rats o * Symptoms and lesions after Mycoplasma infections in mice and rats Behaviour: Torticollis - Respiratory: Pneumonia Kwam niet voor in les Vorige examens: Behavior: * Torticollis Respiratory: * Pneumonia examendoc: Een van de meest erge infecties in ratten. Tast het respiratorisch stelsel aan: Pneumonie e rhinitis + opklimmende infecties naar het middenoor en de hersenen. Infectie is moeilijk te behandelen. Oedemateuze zwellingen op oren en ogen. Soms conjunctivitis, lesies van de huid. Zwelling van de vulva. 4.10. TO WHICH GENERAL SYMPTOMS CAN YOU NOTICE THAT AN ANIMAL IS ILL? EXPLAIN AND GIVE A FEW EXAMPLES. Aan welke algemene symptomen kan je merken dat een dier ziek is? Leg uit en geef enkele voorbeelden. 4.10.1. G IVE TW O BRO A D CL A SSES O F SYMPTO MS General symptoms Answers LAS exam Questions 17 Laboratory Animal Science Symptoms for specific organs 4.10.2. T YPES O F GENERA L SYMPTO MS (3): Behaviour Position Feed and water uptake 4.10.3. G ENERA L , BEHA VIO URA L SYMPTO MS O F DISEA SE (4): o slow (or lack of reaction) o seperation of the group (mice are social animals) o loss of grooming (not washing themselves anymore) o aggression o (misschien ook: pain faces -> kind of grimmas that can give you an estimate about amount of pain) 4.10.4. G ENERA L SYMPTO MS O F DISEA SE : PO SITIO N O F THE A NIMA L (4): hunched back torticollis abnormal limb position ruffled fur 4.10.5. S YMPTO MS CO NCERNING FEED A ND W A TER UPTA KE IN L A B A NIMA L S (5): Loss of appetite Weight loss o Less eating but also less drinking Dehydration !!! o dehydration causes a quicker loss of body weight then eating less o lift skin: if skin is flexible and goes back to normal position fast: ok, if skin is unflexible: very dehydrated (kan je ook doen door in je eigen voorarm de huid eens samen te duwen) Drink less Drink more 4.11. GIVE 5 SPECIFIC ORGAN SYSTEMS THAT CAN BE AFFECTED IN SICK ANIMALS. ENTER FOR EACH OF THESE ORGAN SYSTEMS 3 EXAMPLES OF DISEASE SYMPTOMS THAT CAN BE DETECTED EXTERNALLY. o * Geef 5 specifieke orgaanstelsels die bij zieke dieren kunnen aangetast zijn. Geef voor elk van deze orgaanstelsels 3 voorbeelden van ziektesymptomen die uitwendig waarneembaar zijn. Onderverdeling hieronder was meer om voor mezelf te structureren, niet allemaal aparte examenvragen, maar zo kan je ook oefenen door de headings to collapsen en dan te kijken naar het antwoord =) 4.11.1. S PECIFIC O RGA NS / O RGA N SYSTEMS THA T CA N BE A FFECTED IN SICK A NIMA L S (9): Skin Digestive tract Respiratory tract Genito-urinary tract Answers LAS exam Questions 18 Laboratory Animal Science Circulation Nervous system Limbs Eyes Ears 4.11.2. S YMPTO MS O F THE SKIN IN L A B A NIMA L S o Hair loss o Redness o Wounds o Overt or subcutaneous hemorrhages o Crusts o Abscesses o Tumours o Myxomatous lesions o Fleas, lice, mites 4.11.3. S IGNS O F PRO BL EMS IN THE DIGESTI VE TRA CT O F L A BO RA TO RY A NIMA L S (7): tooth problems hypersalivation vomiting diarhhoea melena undigested feed in faeces worms 4.11.4. S YMPTO MS O F THE RESPIRA TO RY TRA CT IN L A B A NIMA L S (8): Lacrimation / conjunctivitis Swollen eyelids Sneezing Discoloration of fur of forepaws Coughing Nose bleeding Vomiting Dyspnoea 4.11.5. S YMPTO MS O F PRO BL EMS IN THE URINA RY TRA CT O F L A B A NIMA L S (5): Polyuria Stranguria No urine production Blood in urine Frequent loss of small quantities 4.11.6. S YMPTO MS O F PRO BL EMS W ITH THE GENITA L TRA CT IN L A B A NIMA L S (4): Swelling / abscesses genital organs Purulent discharge Redness/swelling mammary gland No milkproduction Answers LAS exam Questions 19 Laboratory Animal Science 4.11.7. S YMPTO MS O F PRO BL EMS W ITH THE CIRCUL A TIO N IN L A B A NIMA L S (6): Tiredness Panting Paresis / paralysis Edema Cyanosis Anaemia (pale mucosae) 4.11.8. S YMPTO MS O F PRO BL EMS W ITH THE NERVO US SYSTEM IN L A BO RA TO RY A NIMA L S (4): Torticollis Paralysis Circling Seizures 4.11.9. S YMPTO MS O F PRO BL EMS W ITH THE L IMBS IN L A B A NIMA L S (5): Limping Stiff walk Swollen joints Fractures Pododermatitis/sore hocks 4.11.10. S YMPTO MS O F PRO BL EMS O F THE EYES IN L A B A NIMA L S (4): Lacrimation Conjunctivitis Swollen eyelids Blindness 4.11.11. S YMPTO MS O F PRO BL EMS O F THE EA RS IN L A B A NIMA L S (3): Crusts Swelling and redness Scratching 4.12. WHAT IS THE IMPORTANCE OF DISEASES AND SUBCLINICAL DISORDERS IN LABORATORY ANIMALS? It can have an effect on: animal behavior, body weight, organ functions, feed and water uptake, change in hematological and biochemical blood values, organ weight, activated immune response. If you are testing a drug, you could think that is works/doesn’t work or causes some strange side effects when it’s caused by the disease. A pathogen can also interfere with the immunologic response, with physiological properties of tissues, can be oncogenic (vb: viruses),… it’s also possible that a contamination can be present in a tissue or cell culture that you derive from the animal. Animal death due to disease can cause a change in the animal number which can interfere with statistics or make it difficult to draw conclusions. Answers LAS exam Questions 20 Laboratory Animal Science It’s possible that an animal is a subclinical carrier, then you will be unaware of the disease. 4.13. DIFFERENT APPROACHES TO DISEASED LAB ANIMALS (5): o - Welke toepassingen kan je doen (naar de overgebleven dieren toe) nadat een ziekte is gediagnostiseerd bij een dier? Depending on the situation: o euthanasia o quarentaine (also for animals you think may not be affected yet) o treatment (e.g. Antibiotics, test microbial susceptibility before treating) o vaccination (only in select cases, takes time to be effective) o Always search for cause of disease (!!!) 4.14. DISCUSS 3 NON-INFECTIOUS CAUSES OF DISEASES IN MICE (ALTERNATIVELY: RATS). o * Bespreek 3 niet-infectieuze oorzaken van ziekten bij muizen. o * Bespreek 3 niet-infectieuze oorzaken van ziekten bij ratten. 4.15. NON-INFECTIOUS CAUSES OF DISEASE IN LAB ANIMALS (7): o Feed o Housing o Toxins o Metabolic o Trauma o Tumours o Innate / hereditary Specifically in rodents (rats/mice): o Teeth of rodents grow continuously -> need to be reduced by eating Can lead to: incisor overgrowth -> into lip -> not able to eat anymore o Bite wounds o barbering: abnormal grooming behavior of an animal chewing and tearing the fur and whiskers of either itself or another animal. due to boredom o 5. TAXONOMY (PROF. DR. P. CORNILLIE) 5.1. ALGEMENE UITLEG Les is wel interessant, ook alle examenvragen van vorige jaren komen uit het stuk van de ppt waarvan hij nu zei dat het niet te kennen is, ik denk dat het daarom geen slecht idee deze lecture eens te checken indien je tijd hebt, duurt iets meer dan een uur Lecture: 1:12:25 what do you need to know? => van daar tot einde vage uitleg over examen o Groot idee hebben van hoe verschillende groepen/species met elkaar verwant zijn o Hij zei dat deez slide vooral interessant was: dus dit zeker proberen begrijpen o “this slide is something that you have to know uh bear in mind” Answers LAS exam Questions 21 Laboratory Animal Science o “will I ask you a question directly on this subject, no, but in embryology for example: compare rodent species vs non-rodent species, and then you need to know e.g. rabbit is not a rodent”. o Ook weten welke species dichter bij andere staan zoals af te leiden uit stambomen e.g. “ruminants are more distantly related to tylopods than swine” o Ik ga volgende 3 stambomen vanbuiten leren voor mezelf zodat ik de balangrijkste species kan plaatsen, heb ze lichtjes aangepast met fototjes en inde onderste wat extra termen om het duidelijker te maken voor mezelf Answers LAS exam Questions 22 Laboratory Animal Science 5.2. GIVE THE TAXONOMIC CLASSIFICATION OF THE RABBIT, MOUSE, GUINEA PIG, DOG, RHESUS MONKEY OR SHEEP Staat vanaf dia 43 (FYI) in zijn ppt, hij zei echter tijdens de opname dat dit niet te kennen is “only for your interest not for you examination” Ik skip dit maar heb hier nog de info van vorige jaren toegevoegd indien iemand dit toch graag wil voorbereiden. Nota’s doc 2. Taxonomy of vertebrates * Geef de taxonomische classificatie van het konijn, muis, cavia, hond, rhesus monkey en aap of schaap. * Describe the taxonomical position of the rabbit (use 5 taxonomical terms) Answers LAS exam Questions 23 Laboratory Animal Science 1. Taxonomy of vertebrates * Geef de taxonomische classificatie van het konijn, muis, cavia, hond, rhesus monkey en aap of schaap. SUBphylum Class Order Family Genus Species Vertebrates Mammalia Placentalia Boreoeuteria Lagomorpha Leporidae Oryctolagus Oryctolagus cuniculus (=Rabbit) Rodentia Muridae Mus Mus musculus (=mouse) Rodentia Caviidae Cavia Cavia procellus (=Guinea pig) Primates Cercopithecidae Macaca Macaca mulatta (Rhesus monkey) Ruminantia Bovidae Ovis Ovis aries (=sheep) Carnivora Canidae Canis Canis lupus (=dog) EXTRA : Phylum : Vertebrates = Animals with vertebral column Class : - Fish (Zebrafish) - Amphibians (Xenopus) - Reptiles - Birds Answers LAS exam Questions 24 Laboratory Animal Science - Mammals Order : Family : Genus : Species : o Species name = Binomen (In 2 delen) : Genus name : italics + Capital Species epithet : italics Vb. Danio rerio (= Zebra fish) 6. REPRODUCTION AND REPRODUCTIVE TECHNIQUES (PROF. DR. A. VAN SOOM) 6.1. DIFFERENCE COPULATION PLUG/POST-OVULATORY DISCHARGE (+DIFF. SPECIES) In Golden hamster : post-ovulatory discharge: the day after ovulation “proof” that animal has ovulated = thick creamy white material with cheesy odour in animal that has OVULATED (NOT MATED) Can also be used to know whether golden hamster is (pseudo)pregnant or not If there is post-ovulatory discharge detected at day 5 and day 9 : NO pregnancy If detected at day 10 : pseudo-pregnant If none detected : really pregnant Coagulating plug/copulatory plug: In rat and mouse: Formed after mating! Does not mean the animal is pregnant, only “proof” that the animal has mated. - Because mice usually mate 4-6 hours into the dark cycle, look for a plug as early into the light cycle as possible. - Otherwise, the plug may be dislodged or dissolved. - The nature and location of the vaginal plug can be a strain characteristic: it is superficially evident in some strains but deep in the vagina in others. If it is deep, it can usually be seen by opening the vagina gently with a blunt flat tooth pick or blunt metal probe. The presence of a plug indicates only that the female has mated, not that she has conceived. 6.2. DISCUSS BREEDING SCHEMES: PRO/CONTRA OF EACH SCHEME Ze heeft hier weinig over gezegd over pros and cons PPT: GOLDEN HAMSTER: - Monogamous pairs : o continuously (aggressive behaviour of female possible) Answers LAS exam Questions 25 Laboratory Animal Science o hand mating (put female with male after dark) Putting male in female cage: will be teritorial and attack male, even when in oestrus True for most other animals: bring female to male place Other way around: female may be aggressive and defend territory - Polygamous matings or harem system (1-4 males with 5-15 females): lots of fighting => not interesting MICE : - Monogamous pair (1 male, 1 female) - Trios (1 male, 2 female) - Harem (1 male, 3 to 6 female) Guinea Pig: - Monogamous: stay together o - postpartum mating is common (5 litters per year) o Don(t let postpartum mating happen all the time, or sow will be exhausted - Polygamous : 1 male and 8-10 females- separation of pregnant females until few weeks after delivery 6.3. EFFECTS OF PHEROMONES IN MURINES * Lee-Boot/Whitten/Bruce effect, explain - Lee-Boot effect : cycle of female mice housed together slows down or stops - Whitten effect : exposure of such mice to male urine will cause them to cycle again (synchronize) (on 3rd night of exposure) - Vandenbergh effect: exposure to male mouse will bring about puberty in female mouse 6.4. EVOLUTIONARY ADVANTAGE OF BRUCE EFFECT IN MOUSE REPRODUCTION. (kan ook voorkomen in golden hamster) - Bruce effect : impregnated mouse will abort pregnancy when exposed to strange male within 24 h of pregnancy - PPT: Female mouse will abort during first days of pregnancy : why? o Exposure to strange male urine means that original partner has been defeated or killed by new, stronger male => more suitable to father pups Nog wat extra inzichten van wikipedia: Males When given the opportunity, male mice tend to direct their urine in the female's direction. This allows males to improve their fitness success by "sabotaging" the pregnancy of a male competitor, and more quickly returning the female to estrus. The Bruce effect can also aid in maintaining social status, with dominant males leaving more urinal scent markings, and so blocking the pregnancies initiated by subordinate males. Females Answers LAS exam Questions 26 Laboratory Animal Science Females can control their likelihood of terminating pregnancy by pursuing or avoiding novel male contact during their most susceptible periods. In this way, females can exert a post-copulatory mate choice, reserving their reproductive resources for the highest-quality male. Certainly, females are more likely to seek proximity to dominant males. In many rodent species, males kill unrelated young; pregnancy block may avoid the wasted investment of gestating offspring likely to be killed at birth. The Bruce effect is most common in polygynous rodent species, for which the risk of infanticide is highest. 6.5. ALGEMENE VRAAG DIE VAAK MET VARIATIE TERUGKOMT: DESCRIBE REPRODUCTIVE CHARACTERISTICS OF SPECIES X * Bespreek de reproductie karakteristieken van de gouden hamster/ cavia/mouse/rat/… PPT reproduction in laboratory animals: DIA 41-131 Die vraag komt terug voor verschillende species, en antwoord hierop kan heel uitgebreid zijn, staat wel allemaal in powerppoint “klaar om van buiten te leren” ik denk dat dit gewoon een stuk is waar wat tijd in zal inkruipen =(, je zal zelf moeten bepalen hoe ver je hier in gaat. Ik heb deze tabel genaakt voor mezelf, ik denk dat dit het belangrijkste is, maar bevat veel zaken nog niet(typische karakteristieken, care of young, …): Mouse Rat Golden Hamster Guinea pig Rabbit Weaning at 3-4 W 3W 3W 2-4 W 5-8 W Puberty at 5W 6-8 W 4-6 (F) & 7-9 (M) W 4-5 (F) & 8-10 (M) W 16 (F) & 20 (M) W Breeding at 8-10 W 12-16 W 6-8 (F) & 10-12 (M) W 9-10 W 20-36(F) & 24-40(M) Estrous cycle 4 d (2-9d) 4-5 d Exactly 4 d 14-18d Induced ovulation Estrous duration 14h 14h 2-24h 1-18h / (induced ovulation) Pregnancy duration 19d (18-21d) 21-23d 15-17 days 68 days (59-72d) 30d (28-35d) Litter size 6-12 6-12 6-8 1-6 4-10 6.6. VOORBEELD: DISCUSS THE REPRODUCTION CHARACTERISTICS OF A GOLDEN HAMSTER (CYCLE, GESTATION, PUPS). Reproduction Puberty at 4-6 (F) and 7-9 weeks (M) Breeding at 6-8 (F) and 10-12 weeks (M) Estrous cycle of exactly 4 days Estrus duration 2-24 hours Pregnancy of 15-17 days Litter size 6-8 Weaning at 3 weeks Typical in golden hamsters: Answers LAS exam Questions 27 Laboratory Animal Science Flank organ (androgen dependent) o sebacious gland in the skin typically present in males and androgen dependent o Important for pheromone production Postovulatory discharge (=thick creamy white opaque material with pungent cheesy odor) o is present in an animal that has just ovulated (not an animal that has mated like the copulatory plug) o Proof that animal has ovulated o Can be used to predict breeding times Post-ovulatory disscharge: 1 day after ovulation 3 days later: will ovulate again Monday morning: disscharge: Thursday evening can breed No Whitten–effect Bruce–effect possible Sexing of golden hamsters: At weaning Urogenital distance is larger in males Females have pointed posterior, and two rows of teats on the ventral side Males have rounded scrotal sacs and more pigmented flank organs Copulatory behaviour Female hamster displaying the lordosis posture characteristic of estrus (A). Cutaneus trunci stimulation; in B the tail position in rest and in C during bilateral stimulation of the lateral thoracic nerve, showing the tail in the tail-up position Determination of pregnancy: Postovulatory discharge after mating: o At day 5 and 9 : not pregnant o At day 10 : pseudopregnant May have been real pregnancy but didn’t take Really pregnant: no postovulatory discharge and after day 10, weight gain and abdominal distension Signs of parturition Increase in respiratory rate Restlessness, eating, grooming, nest building Licking of perineal region Answers LAS exam Questions 28 Laboratory Animal Science Care of young Young start suckling immediately after birth Cannibalism of young in primiparous females during first week (biting instead of suckling, noise, disturbance) Fostering newborns is very difficult Young eat solid food from 10 days Weaned at 20-22 days (30-40 g) Very difficult to take away pups when mother attacks them. Other mother will not take them. Give bottle? Very difficult.Can eat solid foods at 10 days. Breeding techniques Monogamous pairs : continuously (aggressive behaviour of female possible) hand mating (put female with male after dark) Polygamous matings or harem system (1-4 males with 5-15 females): fighting ( not interesting because of lots of fighting) o Put female in male cage after dark o Putting male in female cage: will be teritorial and attack male, even when in oestrus o True for most other animals: bring female to male place o Other way around: female may be aggressive and defend territory Breeding problems: o Cannibalism : no disturbance during first week after birth, no attempts to replace the pups o Provide disturbed nursing female with fresh food o Females only breed during first year, males during 2-3 years o Young females < 30 d : neonatal mortality rises o Nulliparous females > 6 m : maternal deaths rises 6.7. HOW TO DETERMINE SUCCESSFUL COPULATION AND PREGNANCY IN MICE? Determination of fertilization: o Vaginal smear o Coagulating plug o Vaginal lavage with spermatozoa Determination of pregnancy: - Vaginal smear: typical aspect for dioestrus (leukocyte invasion) - Mammary and nipple development from day 14 of pregnancy - Abdominal palpation of fetuses at day 14 of pregnancy 6.8. FOR A STUDY OF TERATOGENICITY, IT IS NECESSARY FOR 10 FEMALE MICE AROUND THE SAME POINT BECOME PREGNANT. HOW TO DO THIS? Voor een studie van teratogeniciteit is het nodig dat 10 vrouwelijk muizen rond hetzelfde tijdstip zwanger worden. Hoe zal je dit bewerkstelligen? Answers LAS exam Questions 29 Laboratory Animal Science Check estrous females, if necessary, then: Put female mice together, until their cycle will slow/down/synchronise (Lee-Boot effect). Then expose female them to male mice urine. After 3 days, there is a high probability, that they will be in oestrus (via Whitten effect), so it would be a right time to introduce them (separately or in two) to a male, on a dark phase. Check for a vaginal plug morning after. Around 50% will have mated. 6.9. HOW TO ENSURE GOOD REPRODUCTION OF MICE (MEASURES, PRECAUTIONS?). Breeding procedures: - Appropriate light intensity and photoperiod (14:10) - Allow no shifts in photoperiod or interruptions in light-dark cycle - Maximize no. of weaned pups by moving pregnant female to other cage - Different mating systems possible Breeding problems - Abnormal or irregular day/night cycle - Inappropriate light intensity (Weihe et al 1969) o optimal light intensity (250 lux) for number of litters born o optimum (60 lux) for the number of young per litter - Noise - Inbreeding : depression of fertility 6.10. DEFINITIES REPRODUCTIVE TECHNIQUES IN LABORATORY ANIMALS Prof zei tijdens les: van deze ppt enkel definities van de technieken kennen (alles hiervoor is een andere ppt, dus ook leren!) - Artificial insemination: deposition of semen inside the female genital tract by means of instruments - Embryo tranfer: removing one or more embryos from the reproductive tract of a donor, and transferring them to one or more recipient females - In vitro fertilization: a medical or laboratory procedure whereby an egg is fertilized by sperm in a test tube or elsewhere outside the body (in vitro = in glassware) - ICSI: intracytoplasmic sperm injection: is an in vitro fertilization (IVF) procedure in which a single sperm cell is injected directly into the cytoplasm of an egg. (definitie niet in ppt) - Cryopreservation: Is the process of preserving an embryo or gametes at sub-zero temperatures (mostly at -196°C in liquid nitrogen), generally as diluted semen, individual oocytes or embryos at an embryogenesis stage corresponding to pre-implantation, that is, from fertilisation to the blastocyst stage. - Reproductive cloning: Reproductive cloning is defined as the deliberate production of genetically identical individuals. Each newly produced individual is a clone of the original.It can be performed by embryo splitting or by nucleus transfer 6.11. MULTIPLE CHOICE: TO MATE A HAMSTER YOU HAVE TO A. Put the male into the cage of the female 3 days after postovulatory discharge B. Put the female into the cage of the male 3 days after postovulatory discharge C. Put the male into the cage of the female 3 days after copulatory plug D. Put the female into the cage of the male 3 days after copulatory plug Answers LAS exam Questions 30 Laboratory Animal Science Antwoord en uitleg: (verander font van wingdings in iets anders om te kunnen lezen): Antwoord: B (copulatory plug is only formed after mating, not after ovulation, and we saw it as typical for mice. Post-ovulatory disscharge: 1 day after ovulation ⇒ 3 days later: will ovulate again ⇒ Monday morning: disscharge: Thursday evening can breed Female will defend territory, even if in oestrus => put female in male cage) 6.12. EXTRA : No menopause in animals : ovarian reserve is never exhausted when animal dies, but more degeneration of oocytes at the end of life (in taxonomy legt prof uit dat enkel bepaalde apen en sommige walvissen nog menopause hebben) Superovulation : is induced by administration of eCG (= Equine Chorionic Gonadotropin) & hGC (= Human Chorionic Gonadotropin), which are placental hormones with : - LH activity : causes ovulation - FSH activity : stimulate follicle growth Naturally : 6-12 oocytes Superovulation : 15-50 oocytes 7. COMPARATIVE MORPHOLOGY (PROF. DR. W. DE SPIEGELAERE) 7.1. DEZE ZIJN OFWEL VAN COMP MORPHOLOGY OF COMP PHYSIOLOGY, MAAR GEEN DEFTIG ANTWOORD IN CURSUS (OF MSS VAN ANDER VAK?) * Bespreekhartfrequentie en ademhalingsfrequentie bij dieren. * Graph of blood functions : giving example on oxygen * affinity between an elephant and a mouse. * Derive the formula for body surface area Lecture was super brak: zijn uitleg over examen:Very beginning of lecture II, and very end: - know differences between Rodents and Lagomorphs, what is typical in rats, mice and rabbits Answers LAS exam Questions 31 Laboratory Animal Science - He will give a situation: a certain process/organ needs to be studied: what species will be a good model to study this? - Is danio rerio or one of the rodent models better and discuss pros and contra’s: - Which animal model would be good? - Fish vs mammals, why? 7.2. GIVE 5 MAJOR ANATOMICAL DIFFERENCES BETWEEN RABBITS AND RODENTS * Give 5 major anatomical differences between rabbits and rodents * Vergelijk het gebit van het konijn en de rat: geef de tandformule, het totaal aantal tanden en welke levenslang doorgroeien Hieronder voor mezelf gestructureerd 7.2.1. W HICH CHA RA CTERIS TI CS DIFFER BETW EEN RA BBITS A ND RO DENTS ( MICE A ND RA T ) (13): Radius and ulna Digits teeth Vertebral formula Uterus Penile bone Perineum Mammary glands Dewlap Gal bladder Fat Stomach Respiratory system 7.2.2. S TO MA CH o Rodents : 2 stomachs (Glandular vs non-glandular) subdivided internally in a thin-walled aglandular proventricle [G : p] and a thick-walled glandular ventricle [G : v] containing fundic glands (folded mucosa; G : pf) and pyloric glands (distally , i.e. to the right; G : pp). The border between the proventricle and the ventricle is formed by a 2 mm high mucosal fold [G : m] extending from the minor curvature to half-way the major curvature of the stomach. o Rabbits : 1 simple stomach , not compartmentalized o stomach [E l] not compartimentalized and entirely lined with glandular epithelium. 7.2.3. R ESPIRA TO RY SYSTEM o Rodents : Left lung : 1 lobe without subdivision / Right lung : 4 lobes o Rabbits : Left lung : 2 lobes / Right lung : 4 lobes 7.2.4. D IFFERENC ES BETW EEN RA BBITS A ND RO DENTS : RA DIUS A ND UL NA Rabbit: Radius and ulna fused Answers LAS exam Questions 32 Laboratory Animal Science Rodents: Radius and ulna free 7.2.5. D IFFERENC ES BETW EEN RA BBITS A ND RO DENTS : DIGITS Rabbit: - Forepaw: 5 - Hindpaw:4 Rodents: - Forepaw: 4 (actually 5, but reduced pollux) - Hindpaw: 5 7.2.6. D IFFERENC ES BETW EEN RA BBITS A ND RO DENTS : TEETH * Vergelijk het gebit van het konijn en de rat: geef de tandformule, het totaal aantal tanden en welke levenslang doorgroeien Basic informatie Teeth shape: - heterodont: different teeth, typical for mammals - Homodont: have homodont teeth, all look alike (fish, reptiles, …) o Some mammals secondarily evolve to a homodont type: killer whales, sper whales Teeth replacement: - polyphyodont: can replace continiously: sharks, crocodiles - Mammals: Diphyodont or monophyodont: shed once or not at all Teeth growth: - Hypsodont: can continiously grow - Brachydont (human), teeth stop growing when they have their full size Dental formula: I: Incisors C: Canines P: Premolars M: Molars Upper and lower row correspond to upper and lower teeth Rabbit 2I OC 3P 3M 1I OC 2P 3M o Upper jaw: 1 large incisor (fissure) + 1 peg tooth in back (=2nd Incisor), 3 premolars and 3 molars Answers LAS exam Questions 33 Laboratory Animal Science o Lower jaw: 1 large incisor, 2 premolars and 3 molars o Peg tooth and P are diphyodont o I and M are monophyodont (no milk teeth) o All are hypsodont (continuously growing) o Rodents 1I OC 0P 3M 1I OC 0P 3M Monophyodont I are hypsodont M are brachydont 7.2.7. E XPL A IN VERTEBRA L FO RMUL A C: Cervical T: Thoracic L: Lumbar S: Sacral Ca: Caudal 7.2.8. D IFFERENC ES BETW EEN RA BBITS A ND RO DENTS : VERTEBRA L FO RMUL A Rabbit: C7 T12 (13) L7 S4 Ca 14-16 Rat and mice: C7 T13 L6 S4 Ca27-31 7.2.9. D IFFERENC ES BETW EEN RA BBITS A ND RO DENTS : UTERUS Rabbits: Uterus duplex Rat: Uterus duplex Mice: uterus bicornuate (2 horns but 1 cervix) 7.2.10. D IFFERENC ES BETW EEN RA BBITS A ND RO DENTS : PENIL E BO NE Rabbits do not have a penile bone Rodents have a penile bone 7.2.11. D IFFERENC ES BETW EEN RA BBITS A ND RO DENTS : PERINEUM Female rabbit: Anus and urogenital opening Female mouse and rat: Anus, Vagina and urethra 7.2.12. D IFFERENC ES BETW EEN RA BBITS A ND RO DENTS : MA MMA RY GL A NDS Rat: female 6 pairs of teats, male no teats Answers LAS exam Questions 34 Laboratory Animal Science Mice: 5 pairs of teats, male none Rabbit: 4-5 pairs of mammary glands, males none 7.2.13. D IFFERENC ES BETW EEN RA BBITS A ND RO DENTS : DEW L A P Rodents: no Rabbit: yes 7.2.14. D IFFERENC ES BETW EEN RA BBITS A ND RO DENTS : GAL BL A DDER : Rabbit + Rat: - Mouse: + 7.2.15. D IFFERENC ES BETW EEN RA BBITS A ND RO DENTS : FA T Rabbits only have white fat Rats and rodents: have white and brown fat, and are better in cold temperatures 7.2.16. D IFFERENC ES BETW EEN RA BBITS A ND RO DENTS : TEA R GL A ND 7.3. GIVE 5 MAJOR ANATOMICAL DIFFERENCES BETWEEN MICE AND RATS: Ik weet er slechts 3 uit zijn lessen: Mammary glands Rat: female 6 pairs of teats, male no teats Mice: 5 pairs of teats, male none Uterus: Answers LAS exam Questions 35 Laboratory Animal Science Rat: Uterus duplex Mice: uterus bicornuate/bicornis Gal bladder: Rat: - Mouse: + Vond dit nog online Parathyroids: - Rat: one pair - Mouse: variable number of parathyroids, usually 2 but may be more than 2 Relevant differences between rats and mice The rat possesses only one pair of parathyroids. They are located on the anterior and lateral aspect of the thyroid lobes but may vary in position. In the mouse, the position and the number of parathyroids is variable. Usually, there are two parathyroid glands located bilaterally just under the capsule near the dorsolateral border of each thyroid lobe. They are rarely found at the same level, sometimes one or both may be posterior to the thyroid; they may be deeply embedded in the thyroid tissue and there may be more than two. Structure of adrenal gland differs between rat and mouse The mouse adrenal differs from that of the rat by the absence of a zona reticularis in the inner cortex and an additional “X-zone” at the junction between cortex and medulla in females which regresses with age (Nyska and Maronpot, 1999). T 7.4. * VERGELIJK 5 KENMERKEN VAN EEN KNAAGDIER MET DIE VAN DE MENS Weinig over gezegd in zijn les maar hier een goed antwoord van een vorig jaar: - Sweat glands - Mammary glands - Tibia/fibula - Teeth o Growth o Replacement - Mouth - Stomach - Gal bladder - lungs (Rat) Differences : - Sweat glands are restricted to the foot pads - Six pairs of mammary glands + teats (=’tepels’) (rat: 6 pair, mice have 5 pair) - Tibia & fibula are joined together o -> cause less flexibility o -> better for forward movement Answers LAS exam Questions 36 Laboratory Animal Science - Rodents have monophyodont teeth (= no replacement), human teeth are diphyodont (2 sets of teeth) - Rodents : Incisors are hypsodont (keep on growing), while molar teeth are brachyodont (stop growing) o Human teeth are brachydont - Humans have lips, rat have a philtrum instead -> used to moister the nose o -> no lips in the way to get close to food (= nibble =’knabbelen’) - Stomach : rat has 2 parts separated by mucus layer o Non-glandular o Glandular = actual stomach - Gal bladder : o human has one o rat has no gal bladder (mice and rabbit do have a gal bladder) - Lungs : o Human has symmetric lung o rodents and rabbits both have asymmetric lungs, due to subdivision into lobes of 1 or both of the lungs (left & right lung) - Kidney : o Human kidney is multilobular o rodents and rabbits have uniloblar kidney Similarities : - Shoulder human ~ rat - 5 digits (5 vingers) at front and hind paw 7.5. WHY IS KNOWLEDGE OF THEIR MORPHOLOGY IMPORTANT WHEN WORKING WITH LAB ANIMALS? * Waarom is kennis van hun morfologie belangrijk bij het werken met proefdieren? Comparative morphology = Similarities and differences of species brought in perspective to understand functional and evolutionary traits Evolutional development of a part of the body can tell whether this part is really functional or just inherited as evolutionary constraint (=’beperking’) (ook: zei tijdens les dat bepaalde structuren op elkaar lijken maar anatomisch niet dezelfde zijn) 7.6. EXTRA SAMENVATTING VAN VORIGE JAREN DIE EEN STUK DUIDELIJKER IS DAN ZIJN LES =) Zou ik eventueel bekijken indien je tijd over hebt Integument Fish & Amphibian ( mammal) : Breath through skin Skeleton Hard to compare Answers LAS exam Questions 37 Laboratory Animal Science Ear bones (now in mammals) : evolution from dual function 1) Hearing by putting jaw on floor 2) Articulation To only 1 function : hearing Bucal cavity (mond) - Shape of teeth : o Heterodont (different teeth = mammals) o Homodont (all same teeth) - Teeth replacement : o Polyphyodonty (shed teeth multiple times) o Diphyodonty (shed teeth twice) - Growth : o Hypsodont (keep growing) o Brachydont (stop growing) Stomach & intestines Big diversity Birds (!) vb. Pigeon -> Crop : milky substance that is used to feed chicks Rodents (!) : stomach composed of 2 parts : - Glandular stomach - Fore stomach = non-glandular Ruminants vs Rodents : cellular digestion - Rodents : in hind gut > Storage of grass in caecum (intestine) o > Digestion of cellulose - Ruminants : in fore gut o > digestion in stomach o > Rejew on it (advantageous because get more nutrients out of it) Gal bladder Periodic eaters vs Continuous eaters - Human = periodic > bile is produced and pushed out when we have eaten - Rodents = continuous o > don’t need gal bladder Circuatory system Fish vs mammals : - Fish : very simple,
