ANP 818.docx

**ANP 818: REPRODUCTIVE MANAGEMENT AND CONTROLLED BREEDING** **Course Outline** 1. **Flushing and Steaming up** 2. **Neonatal management** 3. **Oestrus detection, mating system, pregnancy diagnosis** 4. **Sire management** 5. **Management of reproductive disorders** 6. **Management of b...

**ANP 818: REPRODUCTIVE MANAGEMENT AND CONTROLLED BREEDING** **Course Outline** 1. **Flushing and Steaming up** 2. **Neonatal management** 3. **Oestrus detection, mating system, pregnancy diagnosis** 4. **Sire management** 5. **Management of reproductive disorders** 6. **Management of breeding records** 7. **Use of Computer in reproductive data management** 8. **Synchronized breeding, accelerated lambing/kidding** **3credits; 30h Theory, 45h Practical, Elective** **Dr K.M. OKUKPE** **Introduction** Sexual reproduction is the process through which offspring is produced from the fusion of male (spermatozoon) and female (ovum) gamete after mitotic and meiotic division. It is the formation of a new individual following the union of two gametes that are different in structure (anisogamy) and are contributed by different parents. Gametes need motility to be able to meet/unite and food to nourish the developing embryo. These two important needs are met by anisogametes i.e. the sperm are motile and small while eggs contain food. Successful reproduction involves a series of physiological and psychology events which must be properly timed. The timing is achieved through the endocrine system by the production of several hormones. It involves heterosexual mating of pubertal animals, fertilization, gestation, parturition and lactation. Animal production revolves around reproduction since it must occur for replacement stock in meat, egg and milk production. Reproductive management of animals requires a mixture of science, technology and the art of animal husbandry. Many pregnancies occur or fail due to the various ways human interfere in an attempt to control the complex physiologic pathways and mechanisms that lead to and support pregnancy and eventual parturition. Reproductive management is directly proportional to reproductive efficiency, and has profound effects on production efficiency, profitability, and sustainability of commercial livestock production. For example, reproductive efficiency is ten (10) times more important than carcass quality and five (5) times more important than calf growth rate in beef herds. Optimal reproductive efficiency requires excellent management, not only of reproduction, but of the environment, feed, etc. Since objectives for reproductive efficiency are species and even herd or flock specific, data to monitor progress should be frequently collected, analyzed and reported. Management, including genetic selection and nutrition, is critical to good reproductive performance. The efficiency of reproduction can be assess from several measures or parameters, which are termed reproductive indices. Each index provides information on a specific aspect of fertility but has its particular value as well as limitations. Therefore, in order to obtain an assessment of the overall reproductive performance at a given time or over a long period, several of these indices need to be used. Some indices are applicable only to a herd or population of cows, while others can also be used in individual animals. In heifer, the important indices include age of attainment of puberty and age at first calving. Age of attainment of puberty depends on the time of onset of ovarian activity, while age at first calving is influenced by the time of conception. For example, under free range conditions with free access to bulls, heifers will usually conceive soon after puberty while in a confined system conception is dependent on the efficiency of heat detection, timing of service and other related factors, all of which have important influence on the age of first calving. **Conception rate** (CR): This is the percentage of animals conceiving (based on pregnancy diagnosis by rectal palpation) relative to the number of animals which have been served. It is usual to calculate it either as CR to the first service only, or as overall CR. **Pregnancy rate** (PR): This is the percentage of animals becoming pregnant (usually over a one year period) relative to all breedable females in the herd. **Calving rate**: This is the percentage of breedable females which calve during a given year. **Number of Services per Conception** (SIC): This is the total number of services given to a group of conceiving cows, divided by the number of conceiving cows. These indices are all influenced by factors related to the cow, the bull or artificial insemination (AI) and the farming system. **Non-return rate** (NRR): This is an index often used by artificial insemination (AI) services to evaluate the success of their operations. This is calculated as 30, 60 or 90 day NRR and refers to the percentage of animals which were serviced but did not return for a repeat service within the specified period, the assumption being that they conceived. Its usefulness is limited to situations where AI is the sole method of breeding and the recording systems are foolproof. Under many tropical smallholder systems, the more likely reasons for 'non-return' to AI are the use of a stud bull or sale of the cow when the farmer found out that it had not conceived with AI. Thus, the use of NRR by AI organisations under such conditions is meaningless. **Calving interval** (CI): This is possibly the single index which provides most information on reproductive efficiency, either in individual cow or in a herd. It is made up of three components -- (a) interval from first calving to first oestrus (postpartum anoestrus period), (b) interval from first oestrus to conception (service period) i.e. (a+b = open period), (c) interval from conception to calving (gestation period). In order to maintain optimum economic benefits under modern intensive dairy systems. It is generally accepted that the CI should be around one year. Since the average gestation length is 280 to 285days, a cow must become pregnant by 80 to 85 days after calving in order to achieve this. The cow must commence ovarian activity early during the postpartum period, show heat, conceive readily, carry the pregnancy successfully and produce a calf. The farmer must detect heat, mate the cow at the correct time and provide adequate nutrition and other inputs. The relative importance of these factors varies in the different smallholder farming systems. For example, under extensive free grazing conditions nutritional fluctuations due to seasonal shortages in herbage cause delays in puberty and the postpartum cycle. However, if the cows are grazing with intact bulls, they readily become pregnant once ovarian activity commences. In tethered grazing or confined systems, factors such as heat detection, timing of mating or AI quality are more important. The presence of the calf and suckling frequency, also influence postpartum ovarian activity in some smallholder systems. **ANIMAL IMPROVEMENT** Animal improvement refers to the ways of developing/breeding only those animals that shows the greatest merits under consideration, such as good feed conversion, growth rate, disease resistance, egg size, etc. It also involves the upgrading of existing (native) breeds as a result of some desirable characteristics which they possess. It also entails the incorporation of genes for desirable characteristics in animals not already possessing them. This leads to manipulation of such characteristics like increase in gene frequency of such genes in populations in which they already exist and removal of or decrease in the frequency of genes responsible for undesirable characteristics in animals. This is done by bringing into a farm or country high quality breeds of livestock or semen with a high productive capacity/ other good characteristics. It is also done by selection of individual within the stock that possess more of the desirable characteristics and mating of such individual to produce more of the desired animals. Breeding is the selective control of mating in plants/animals to produce organisms with better genetic pool to serve human needs for food, work, sport or aesthetics. The aims of animal improvement are: 1. To produce animals that can give high yield in form of meat, eggs, milk, etc 2. To produce animals that can provide high quality products like low backfat thickness, yolk size, shell thickness, etc 3. To produce animals with high feed conversion efficiency. 4. To produce animals with high growth rate and early maturity. 5. To produce animals that can adapt to climatic/ environmental conditions. 6. To produce animals that are resistant to parasites and diseases. The processes of animal improvement are: Selection: Selection picks from a mixed population of animals with breeding values as parents. This is done so that genetic attributes are transmitted from parents to the offspring. Selection could be natural or artificial. Natural selection results from the action of natural forces that leads to the elimination of unfit individuals in a population in favour of the fittest individual. Artificial selection on the other hand is a deliberate attempt by man to ensure the continued transmission of a desirable trait or the removal of undesirable one by allowing only animals with desired trait to produce offspring. Artificial selection could therefore be individual or mass selection, family selection, sibling selection, progeny selection, pedigree selection, etc. Mass or individual selection involves the selection of animals based on their individual performances. Family selection involve the selection or rejection of individuals based on the performance of their relatives or family. It is used when heritability is low and environmental effect is high and when environmental effect common to members of the same family is not high. The larger the family size the more reliable the results. Sibling selection involve the selection of an individual based on the performance of its siblings i.e. brother, sister, half-brother/half-sister. Progeny selection involves the use of the offspring (progeny) of an individual to estimate its genetic potential. The average value of several samples of a gene from the same parent is believed to give a true value of the parent's genetic makeup. Pedigree selection involves the selection of an individual based on the performance of their ancestors. This method is useful when little, or no information, are available on the animals themselves because of their age or sex. **BREEDING** **Breeding** involves the development of animals by transferring inherited qualities from parents to offsprings. A **breed** is a group of domestic animals that has homogeneous appearance, behaviour and other characteristics that distinguish it from other animals. A **breeding stock** is a group of animals used for the purpose of planned breeding. Valuable traits such as fast growth, lean meat, muscular body, reproductive efficiency, egg, meat, milk, or wool production, etc are normally looked out for before an animal is selected as a breeding stock. **Breeding system** is the various ways the breeding stocks are chosen and combined to produce the offspring generation. The common breeding systems are purebred breeding, inbreeding, line breeding, outbreeding, and crossbreeding. **Purebred breeding** is the mating of animals that are of the same breed for the purpose of maintaining such breed. It aimed at establishing and maintaining stable traits that animals will pass to the next generation i.e. improved blood lines or breeds or seedstock that are superior to the original parent. **Inbreeding** is the mating of animals that are genetically closely related than the average population e.g. mating of sibling, sire to daughter, son to dam and one sire herd i.e. mating of animals that have one or more common ancestors. It makes more pairs of genes in the population homozygous. The more closely related the individuals, the greater the degree of inbreeding. **Line breeding** is a mild form of inbreeding which is directed towards keeping the offspring related to some highly priced ancestor i.e. the degree of relationship is less intense than in conventional inbreeding. Linebreeding is not to increase homozygosity but to maintain a high relationship to an outstanding ancestor. **Outbreeding** is a form of pure-breeding which involves mating of animals that are of the same breed but have no closer relationship than at least 4 to 6 generations. It is the mating of members of the same breed that are less related than the average of the population. It has the effect of increasing heterozygosity. **Crossbreeding** involves the mating of animals from two or more breeds to increase the level of heterozygousity. It is the systematic utilization of different breeds to produce crossbred progeny of a specific type. It increases hybrid vigor or heterosis and improve breed complementarity. Breed complementation implies crossing breeds so that their strengths and weaknesses complement one another. Heterosis is the increase in productivity in the crossbred progeny above the average of breeds or lines that are crossed. **CONTROLLED BREEDING** Controlled breeding is the manipulation of reproductive processes of farm animals to suit management objectives. It is primarily aimed at achieving synchronized breeding and parturition, enhancement of litter size and postnatal survival, controlled parturition as well as optimization of reproductive performance in intensive production systems. The advantages of controlled breeding are: i. It saves time in oestrus detection ii. It allows for more efficient use of labour iii. It often leads to improved productivity iv. It gives greater control over the production cycle v. It streamlines and facilitates animal management vi. It enhances accurate record keeping on animal performance. The disadvantages of controlled breeding are: i. It often involves additional costs in the provision of extra feed, drug and breeding aids ii. It may require specialized skills and expertise which may need to be out-sourced iii. It can lead to disastrous outcome such as high peri-natal mortality rate without adequate physical facilities. **Basic principles of controlled breeding of animals** For the basic principles of controlled breeding to be efficient, there must be adequate information on the age at puberty of the animal, the oestrous cycle length and the gestation length to determine the expected parturition dates following successful mating. The basic principles of controlled breeding include the following -- 1. Separation of the male and female animals into different herds or flocks prior to the attainment of puberty. 2. Utilization of an efficient oestrus detection method in combination with pen-mating, hand-mating or artificial insemination. 3. Ensuring correct joining ratios of breeding males to females taking into consideration the breeding capacity of the males and the duration of the joining for flock or herd mating. 4. Keeping of accurate breeding records as the basis for planned interventions in the production cycle. 5. Ensuring availability of adequate physical facilities for the care of large numbers of offspring at a time. 6. Ensuring adequate feeding and health management to support high reproductive efficiency in the farm animals. 7. Ensuring controlled breeding interventions are cost-effective. Flushing and Steaming-up Flushing is the increase in feeding rate of an animal before mating in order to increase the number of ova produced. Steaming-up is the increase of feed some months before parturition in order to increase the birth weight of the offspring. It is the practice of feeding extra rations, especially grain and concentrates to pregnant females in an attempt to promote maximum milk production from the very beginning of lactation. Feeding usually commences about 4 weeks before the due date. It is a process by which farmers provide extra concentrates to pregnant females in the last trimester to avoid any complications during parturition and produce healthy offspring. Steaming up ensures birth of healthy offspring, provides nutrients for maximum foetal growth, build up energy for parturition, increases/maintain high milk yield after birth/ stimulates development of alveoli, promotes good health of dam and accustoms the dam to concentrate feeding. Creep feed is the feed containing a high quality protein meant to be a close substitute to the dams milk. It is very digestible and consist of milk and milk by-products. **Neonatal Management:** The neonatal period extends from birth to somewhere between two weeks and one month, and it is the period of colostrum. Immediately a foetus is given birth to, uterine contraction force blood, fluid and placenta from the dam's body. The umbilical cord which is the foetus lifeline to the dam is now cut off. Without the placenta to remove waste, carbon (iv) oxide (CO~2~) builds up in the foetus blood. In human, a new born's (neonate) is often greyish-dusky blue in colour. The skin colour returns to normal tone within a minute or two of birth as soon as the newborn begins to breathe. Neonates are wet, covered in streaks of blood and coated with a white substance known as *Vernix caseosa* which is believed to be antibacterial. In human, the neonate may have various other birth marks or peeling skin, particularly at the wrist, hand, ankle and feet. A neonate shoulder and hips are narrow, the abdomen protrudes slightly and the fore- and hind legs are relatively short. A neonate's head is very large in proportion to the rest of the body, and the cranium is enormous relative to the face. At birth, many region of the neonate skull have not yet been converted to bone. These soft spots are known as fontanels. During parturition the neonate's skull changes shape to fit into the birth canal, sometimes causing the neonate to have a mis-shapened or elongated head. This will usually return to normal on its own within a few days or week. A neonate genital are enlarged and reddened with the male having an unusually large scrotum. In human, the breast may also be enlarged even in males and this is caused by naturally occuring maternal hormones and it's a temporal condition. Females and even males may actually discharge milk from their nipples or a bloody or milky-like substance from the vagina. This is normal and will disappear with time. The umbilical cord of neonate is bluish-white in colour and it is usually cut after birth leaving 1-2 inches stub in human. The stub will dryout, shrinken, darkened and spontaneously falls off within about 3weeks. By the end of the first year, the neonate height is increased by 50% and by the second year, it would have increased to about 75%. During the day, before a growth spurt, the neonates are irritable and very hungry. The best way to estimate a neonate's physical maturity is to use skeletal age; a measure of bone development. This could be done by having an x-ray of the long bone of the body to see the extent to which the soft pliable cartilage has hardened into bone. The head develops more rapidly than the lower part of the body. Neonatal management involve keeping the neonate in a condition that reduces stress and death. The dam could be assisted in the birth process and the neonate respiratory tract cleared of mucus or any object that could lead to suffocation. The neonate should be assisted to locate the mammary gland and where necessary the navel should be treated with tincture of iodine. In sow farrowing crates are often provided to prevent the dam lying on the piglets. Iron dextran injection should also be provided to piglet because of iron deficiency in piglets. Where necessary heat should be provided to neonate by the dam or the pen could be heated. Straw bedding should be provided in dam pens to provide insulation and heat loss in pens. OESTRUS DETECTION Oestrus and oestrous cycles are physiological states in farm animals with slight differences in duration, signs, intensity and lengths. Oestrus or heat is the period (3 -- 24hours) during which the female animal is receptive to the male and will stand for mating. Oestrous cycle is the interval from the beginning of one heat (oestrus) period to the beginning of the next that is characterised by a chain of cyclical or recurring events which repeat themselves on the average every 21 days (range of 17 -- 24days). It is divided into two broad phases -- follicular and luteal phases which are further divided into four stages -- pro-oestrus, oestrus, metoestrus and dioestrus. **Pro-oestrus** is the period of preparation for oestrus. It is the stage immediately preceeding oestrus when there is increased follicular growth and regression of the corpus luteum (CL). It is characterised by some behavioural signs which indicate the approach of oestrus such as increased frequency of attempts to mount other cows and moving away when mounted. This period lasts for 2days. **Oestrus** is the period of desire heat. It is the only visually definable stage of the oestrus cycle. It is a behavioural state that is characterised by willingness of the cow to stand to be mounted; it lasts on average of 12hours (range 3 -24hours). Ovulation occurs about 12 hours after the end of oestrus. **Met-oestrus** is the period of reorganisation. It is the stage after the end of oestrus when the follicle matures, ovulates and the CL starts to develop. The early part of it is characterised by behavioural signs very similar to those observed during pro-oestrus except that while in pro-oestrus the distance between cows is decreasing with the passage of time, it is increasing in met-oestrus. The duration is 3 days. **Di-oestrus** is the period of preparation for pregnancy. It is the stage of the oestrous cycle following metoestrus when the CL is the dominant structure and the genitalia (as well as the entire animal) is quiescent. The duration is 15 days. The duration of oestrous cycle is 21days in cow with duration of 24hours for oestrus. Observed signs of oestrus in cow include: swollen and reddened vulva, clear mucus discharge from vulva, mounting on other animals and standing to be mounted, incessant noise-making and restlessness. **Oestrus signs and behavioural patterns** VISUAL SIGNS 1. Standing to be mounted: This is the best single sign that a cow is in oestrus. There is a 90% certainty that the cow that stands solidly to be mounted without walking away is in oestrus. There is only a 50% chance that the cow that mounts another is in oestrus. The key feature is, therefore, standing to be mounted. However, not all cycling animals show this clear-cut behavioural sign of oestrus. Other ancillary signs of oestrus, therefore, become indicated and they usually occur in a pattern. (a) pairing/togetherness and grouping, (b) licking and rubbing each other, (c) sniffing and licking of the vulva of another cow. Sexually active cows would approach other cows and sniff their vulva. If the cow approached is in dioestrus, the sexually-active cow would move on. If the cow approached is in pro-oestrus or oestrus, the sexually-active cow would stay in attendance and possibly nudge the vulva with her muzzle and mount. 2. Chin resting and rubbing: This is the resting and rubbing of chin on the rump of another cow by sexually-active cows. It is often a prelude to mounting. It appears that cows which are about to mount test the receptivity of other cows by applying pressure to the rump and loin with the chin. The cow being tested would either give a negative signal by walking away or turning and butting the seeker, or a positive signal by standing quietly. (a) lining up to mount another cow, (b) mounting another cow, (c) standing to be mounted by another cow or bull. These events occur in reverse order as the cow gets out of oestrus. 3. Exhibition of flehmen: This is the lip-curling activity or posture exhibited by sexually-active animals (cows and bull alike). This occurs more frequently if the cow being examined urinates. 4. Oestrual mucus from the vulva: This appears either in the form of long strands from the vulva, or as a smear over the buttocks/tail. Expression of large quantities of mucus from the vulva of cows which are mounting other cows is more frequent and this usually happens when they are dismounting. 5. Ruffling of the rump hair and abrasion of the rump skin: These signs are usually visible over the tail-base, sacral spines and ischial tuberosities. In many cows these signs persist for 4 -- 6 days after oestrus, and so are often very misleading. If abrasions are moist and exude serum, and if the skin temperature over the area is considered on palpation to be warm this usually indicates that the cow is in oestrus, or has just passed out of oestrus. 6. Vulva relaxation, moistness and erythema (reddening): These signs are unreliable as sole signs for oestrus detection. Individual variations in vulval and vestibular colour, shape and size are too great to allow reliable results. (a) tail raising and twitching, (b) increased frequency of urination, (c) excessive bellowing, (d) restlessness, noisiness and walking along fences, (e) decrease in appetite and milk production. NON-VISUAL SIGNS 1. Changes in cervico-vaginal mucus: Mucus becomes less viscous, crystallization or fern patterns shift and NaCl content increases, electrical resistance and dry matter content of mucus decrease. (a) decrease in vaginal pH from 6.98 to 6.45 units, (b) temperature increases slightly at the onset of oestrus and declines more precipitously before ovulation, (c) increase in blood flow, (d) variation in vaginal cytology, (e) hormonal changes, (f) electrical resistance of vaginal mucus membrane decreases from about 200 to 150 ohms. 2. Ovarian changes during the oestrous cycle: During oestrous cycle a continuous sequence of follicle growth and regression or atresia occurs. It is however only during oestrus, and just after, that one or more follicles undergo rapid growth, mature (Graafian follicle) and ovulate. The follicle that ovulates only becomes identifiable approximately 48hour before oestrus. Other follicles frequently grow between days 7 and 14, and it is very common to identify such follicles in association with mature corpus luteum before they regress and become atretic (mid-cycle follicles). Their significance is not understood. At ovulation the Graafian follicle ruptures and the oocyte (egg) is liberated whilst surrounded by a mass of cells (the cumulus oophorus) and is harvested by the fimbrae of the oviduct. The cavity previously occupied by the ruptured follicle (ovulation depression) is quickly invaded by cells of the granulose and theca layers which become lutein cells (luteinization) and form the corpus luteum (CL) which is fully formed at about 7 days post-ovulation and persists for about 15 days before it starts to regress. The regression of the CL is followed by follicular growth and the cycle repeats itself. 1. Visual: There is no substitute for the eyes of the skilled observer who the female animal for oestrus. With good day to dusk checks 80% of oestrus can be detected. Visual observation should be done twice daily, morning and evening for standing oestrus, third additional 1hour observation around 2700hour is very beneficial. 2. Non-visual: The non-visual methods include -- rectal palpation, vaginal mucus microscopy, hormonal changes, controlled oestrus (fixed-time insemination). a. Video tape: mainly for research use b. Heat Mount Detectors (HMD): there are two types of HMD -- KaMar Heat Mount Detectors and Delta Mate Master. KaMar is the most widely used. Both devices are designed to record evidence that a cow has been mounted repeatedly. It is a pressure sensitive device glued to the sacrum of a cow. When a cow wearing a KaMar is mounted by another cow or bull, pressure from the brisket of the mounting animal turns the detector from white to red. c. Chin-ball Mating Device (CMD): This is a robust adjustable halter fitted on the underside with a curve-shaped marker unit with a freely rotating exposed ball bearing. The marker unit has a reservoir of marking fluid and works on similar principles to a common ball-pen. It is strapped to the chin of the vasectomised or pen-o-blocked bull making sure his jaw movements are not restricted. When mounting takes place the ball bearing makes contact with the sides/rump of the oestrus cow thereby making clear stripe marks evident on the back which can be checked at designated time. d. Titanium Dioxide Grease: Daily smearing of the inside of the front legs and brisket of a teaser bull with titanium dioxide grease has been shown to be an effective detection aid. e. Tail painting: Tail painting involves applying a strip enamel paint or 'Painstik' approximately 20cm long and 5cm wide running posteriorly from the middle of the sacrum to second coccygeal vertebra. Types of teasers: There are 3 types of teasers used for oestrus detection, these are vasectomised bull, Pen-o-blocked bull, Hormone-treated (testosterone or oestradiol) females. Oestrous cycle aberrations Once puberty has occurred the female animal should have cyclical oestrous cycle and ovarian activity. The only normal occasions when this does not occur are during pregnancy and for a short time after calving. There are aberrations in oestrous cycles in the following forms: 1. Short oestrous cycles (intervals less than 17days): The reasons for short cycles could be as a result of Follicular cysts. These are persistent anovulatory fluid-filled, thin-walled structures usually greater than 2.5cm in diameter that persist on the ovary for a period of at least 10 days. Cows with this condition are infertile and may show frequent or constant oestrus (nymphomania) or no oestrus at all (anoestrus) although the main behavioural sign will be the excessive and indiscriminate mounting of other cows. There may be excessive vulval mucus discharge. They can be treated with GnRH or HCG or PRID. Cysts should not be intentionally ruptured by squeezing per rectum. 2. Incorrect identification and recording of oestrus. 3. Prolonged oestrous cycles (intervals longer than 24 days). The reasons for prolonged cycles are: (a) Luteal cysts: These are persistent fluid-filled thick-walled lutenized structures that are characterized by an absence of oestrus (anoestrus). Treat with PGF2 alpha alone or GnRH or HCG to be followed 10 days later with PGF2 alpha, (b) Failure to detect oestrus: In these cases the interval will be a multiple of 17 to 24 days i.e. 34 to 48 days when one oestrus is missed, (c) Incorrect identification of oestrus: The cow has been in oestrus but not observed, and then has been incorrectly identified at some stage in the subsequent dioestrus. Intervals will vary between 25 and 35 days, (d) Early embryonic death: When embryos die between days 14 and 42 the lifespan of the CL is extended, hence the prolonged oestrous cycle. **MATING SYSTEM** Mating is the pairing of individuals of the opposite sex, primarily for the purpose of reproduction. A mating system describes how males and females pair when choosing a mate. It describes how an animal society is structured in terms of sexual reproduction and sometimes pair bond behaviour. It refers to the ways that individuals obtain and defend mates as well as well as how many mating partners they have and how they care for their offspring. Males and females differ greatly in the investment each makes to reproduce, and may therefore approach mating with differing strategies. Mating system could be divided into three broad types- 1. Monogamy (pair bonding) 2. Polygamy (polygyny, polyandry and polygynandry) 3. Promiscuity 1. Monogamy: This is a mating system in which a male and a female have an exclusive mating relationship i.e. an exclusive association with a single member of the opposite sex. It is common in birds, though rare in other animals. In animal species, males would generally like to seek extra mates but in many bird species it takes two parents to successfully raise the young ones. The two partners in monogamous relationship stay together to become parenting partners in the defence/care of young ones. The pair bonding may last for a single or many breeding seasons as could be found in birds such as pigeons, penguins, eagles, parrots, etc. Monogamy does not aid genetic diversity very much but as a high benefit to have two parents care for the young and prevent other males form killing them. Even if an animal is generally monogamous, some partners may not always be faithful to one another e.g. Swans sometimes mate outside their primary partnership. Although most human favours monogamous sexual relationships, it is relatively rare throughout the animal kingdom. Homosexual monogamous partnerships have been reported in some species with the two partners forming a lasting sexual bond and helping each other in meeting their daily needs as well as raising offsprings. 2. Polygamy: This is a mating system in which the animals in a partnership mate with multiple partners. A mating relationship in which one male or female have exclusive relationship with two or more partners. There are three types of polygamy -- polygyny, polyandry and polygynandry. a. Polygyny -- This is a polygamous mating system in which one male animal has an exclusive relationship with two or more females. The male often stays with one female to help with rearing her young while the other females are left to rear their young alone. There could be resource (male) defence polygyny, harem or herd polygyny (a defended group of females associated with one male) and leks (male dominant) polygyny i.e. aggregation of males that are seeking (wooing) to attract mates, here females only receive sperm from the males without their helping to raise the young. b. Polyandry -- This is a polygamous mating relationship in which one female has an exclusive relationship with two or more males. The males and the females stay together to rear their offspring and ensures greater reproductive success by providing the female with more mating options/parenting partners. c. Polygynandry -- This is a polygamous mating relationship in which multiple females and males mate with each other. Males may care for the broods of several females. There is loose male and female bond within the group. It ensures greater female reproductive success as the paternity confusion causes the offspring to enjoy the care of many males e.g. Chimpanzees 3. Promiscuity: This is a mating system in which a male or female within the social group mates randomly with any females or males in the same social group. It is common in species with an unpredictable environment. There is no pair bond in this mating relationship and paternal care of the young is rare or completely absent. One mating system is dominant in most animal species, although not all members of the specie will conform to the mating relationship characteristic of the group. A mixture of this mating system may be found in animals belonging to the same species in different geographical location and conditions of food availability. Factors influencing male and female choice of mates Most of the time females are choosier when picking a mate than males, this may be due to the higher investment made by females to produce each gamete. Factors that influence female choice of mates include -- 1. Males with 'good genes' that could ensure better survivorship of the offspring 2. Good potential parenting ability of the male 3. Possession of some resources that may support offspring growth/development 4. Possession of certain traits that are favoured by the females such as colourful or elaborate ornamentation Advantages of female multiple mating 1. Enhances reproductive efficiency through production of offspring 2. Helps to avoid inbreeding 3. Increase genetic diversity among offspring 4. Increase the probability of finding a non-sterile compatible male 5. Enhances heterospermy ARTIFICIAL MATING SYSTEMS IN FARM ANIMALS The desire to ensure high fertility and reproductive success in farm animals has led to the development of different reproductive techniques which have assisted farmers to achieve high pregnancy rates/ reproductive success. The common artificial mating systems or techniques include 1. Hand or Stud mating 2. Pen mating 3. Flock or pasture mating 4. Artificial insemination 1. Hand or Stud mating: This is a mating system in which a female is taking to a males pen periodically for the purpose of mating. Neither the male nor female is allowed to choose its mate as in natural mating system. It's a practice in which one female is brought to a male at a specific time for the purpose of mating, the farmer waits until a successful mating is achieved before he removes the female into its pen. The system ensures the farmers control of the choice of male that mate with a female, eliminate social competitions among males, ensures some males are not over-used, enhances better management of pregnant females through knowledge of mating/pregnancy date and prediction of parturition date, Non-docile females can be removed and re-mated latter rather than allow forceful mating/aggression/injury, risk of injuries to female animal is reduced. The disadvantages of hand mating are that it is time consuming as the farmer must be present to ensure mating occur, it may cause forced mating of unprepared (non-oestrus) female, forced mating may cause trauma/injury/infection of reproductive tract, risk of injuries to handler (farmer) is high. 2. Pen mating: This is an artificial mating system in which one or more females are placed in a confined pen unsupervised with one male for a period of time. The amount of time the animals are placed together/ ratio of male to females is determined by the farmer based on his understanding of the species. In poultry, breeding animals are permanently in floor pens using a mating ration of 1: 8 or 10 male to females, in grasscutters a mating ratio of 1:5 male to females in colony cages (length 2m x width 1m x height 0.4m), guinea pig has mating ratio of 1 boar: 4 -20 sows in colony cages. Most of the disadvantages of hand mating are overcomed with this mating system, but it has the following disadvantages -- farmers cannot determine the certainty of mating/pregnancy, males sometimes become more aggressive/ cause injury to new females, there is need to frequently check on the animals to observe mating/ bullying action, care of pregnant animals may not be optimal as pregnancy/parturition date may not be known. 3. Flock or pasture mating: This is an artificial mating system in which males and females are permanently reared together and mating can take place any time. The males in the flock must identify females on heat and initiate mating. The ratio of males to females in flock mating depends on the species/ other socio-cultural factors. Females observed to be pregnant are either separated or left with the herd until they give birth. Under free range conditions with access to bulls, heifers will usually conceive soon after puberty. In confined systems, efficiency of heat detection, timing of service/other related factors will have important influences on the age at first calving. The advantages of flock mating include increased pregnancy rate/breeding efficiency as males mate oestrus females when observed, decreased risk of reproductive tract trauma/infection, less time is required from the farmer to manage breeding programme. The major challenges are that dominant males could become overused, there could be increased in breeding rate/low flock performance, there is poor management of pregnant females due to inability to predict pregnancy/parturition date. 4. Artificial Insemination: This is the manual collection of semen from proven males, its processing and introduction into the female reproductive tract of an oestrus female. This is in contrast to the natural means that involve mounting, intromission and ejaculation. It involves three basic steps -- semen collection, semen evaluation, semen preservation or extension and insemination (introduction into the oestrus female genital tract for the purpose of fertilization, *in-vivo* fertilization). In other clime the sperm and ovum can first be collected, mixed together for fertilization in a nutrient medium outside the female body (*in-vitro* fertilization) followed by implantation in a primed female uterus or preserved for future use. This processes help the farmer to maximize the potentials of genetically superior females which has been superovulated. This technique has been used successfully in all farm animals such as cattle, sheep, goat, swine, rabbit, chicken and fish with over 90% of dairy cows artificially inseminated in most developed countries. 1. It allows the use of outstanding sires and dissemination of valuable genetic material even to small farms. 2. It reduces the risk of the spread of sexually transmitted diseases such as Brucellosis, Leptospirosis, Trichomonas, etc. 3. Semen export reduces the cost of international transport since it is lesser to import semen than the animals thereby promoting world trade in genetic resources. 4. It solves time/space constraints in animal breeding due to the possibility of preserving semen for a long period, allowing the use of dead proven sire. 5. It enables better planning of breeding/ production programme with the aid of oestrus synchronization and insemination of large number of animals with adequate record keeping. 6. Provide a research tool for investigating many aspect of male and female reproductive potentials. 7. It reduces production cost as it is much cheaper to use AI than keeping stud bulls. 8. It allows cross-breeding to change production emphasis e.g. a change from beef to dairy animals. 9. It makes possible the introduction of new genetic material through the importation of semen. Disadvantages of Artificial Insemination 1. It requires skilled technicians that are in short supply in villages. 2. It is not subject to the nomadic production system. 3. It is in social conflict with the stereotyped nomadic idea, prompting the reference to AI progeny as bastards. 4. It is ineffective due to the absence of a clearly defined breeding pod. 5. Lack of adequate infrastructures such as electricity, supply of cryogens, good roads, etc in developing countries renders it ineffective. 1. Quality of semen i.e. care of semen during collection, processing, storage and insemination. 2. Time of insemination 3. Semen dose for insemination 4. Fertility of female 5. Technician/ inseminators skill **PREGNANCY DIAGNOSIS** Pregnancy is the period of gestation which starts with the union of the male and female nuclei (syngamy) to form a zygote, its development to foetus and terminates at parturition. Expulsion of a dead embryo or foetus that has reached a recognizable size is called abortion. Based on the size of the individual and the development of its tissues/organs, the pregnancy period can be roughly divided into 3 parts -- 1. The period of the ovum or blastula 2. Period of the embryo and organogenesis 3. Period of the foetus and foetal growth Table 1: Gestation Length in farm animals **Species** **Length of gestation (days)** ------------- -------------------------------- Cow 282 Ewe 148 Doe(goat) 148 Sow 114 Mare 350 Woman 280 Rat 22 Rabbit 29 Bitch 61 Pregnancy diagnosis is particularly important (1) in the timely detection of non-pregnant animals for early rebreeding. Ideally, pregnancy diagnosis should be conducted before the first oestrus following mating. Unfortunately, practical methods for a definite diagnosis at this time are not available. (2) to detect non-productive animals for culling. (3) a practical diagnosis is important to confirm diagnosis based on non-return to oestrus, especially in cattle. It has been reported that 15 to 25% of bred cows and heifers that did not return to oestrus and so assumed pregnant were actually not pregnant. Methods employed in pregnancy diagnosis include: a. Palpation of the genital organs per rectum in cattle b. Measurement of progesterone by radioimmunoassay (RIA) or enzymeimmunoassay (EIA) methods c. Non-return rates -- ewe and goat d. Radiography e. Use of ultrasonic Doppler instrument f. Laparoscopy Immunological pregnancy tests are available which can diagnose pregnancy before clinical signs are detected. The tests rely on advanced technology made on a sample of the dam's blood or urine to measure the level of the pregnancy hormone. In this immune assay test, latex particles coated with anti-HCG antibodies are precipitated by urine containing human chorionic gonadotropin (HCG). Test on urine becomes positive within three days after fertilization or when oestrus or menstrual period is missed using the pregnancy strip. The absorbent strip shows the animal is pregnant when dipped in early morning urine stream for 10 seconds and after a few minutes two lines appear in the result window. Even if one of the lines is very light, it means the test is positive. No pregnancy hormone has been detected if after a few minutes only one line is showing in the result window. The test is only useful in the early stages of pregnancy to detect the presence of the HCG. Ultasound scanning can also be used to diagnose pregnancy. The sound waves 'echo' off different tissues and can be translated into a picture. Ultrasound can detect the presence of the sac in which the foetus lies and the foetus itself (from the 7^th^ week of pregnancy in human). The pregnancy detector tool makes use of ultrasound method of diagnosing a foetus filled uterus. MANAGEMENT OF REPRODUCTIVE DISORDERS A number of conditions may interfere with pregnancy at any stage of pregnancy. These include the following: 1. Abortion: Abortion or premature termination of pregnancy may occur in farm animals unnoticed, resulting in death and unseen expulsion of ova, embryos (miscarriage) or foetuses, usually classified as infertility because they cause irregular or prolonged period of anoestrus. In general, incidence of 2 to 5% abortion in a herd of cattle should be viewed seriously and the cause investigated. The cause of abortion may be grouped into physical, genetic or chromosomal, nutritional, chemical, drug, hormonal, infectious, and miscellaneous causes. 2. True/false extra-uterine pregnancy: In true extrauterine pregnancy the embryo or foetus establishes nutritional relations with organs or tissues other than the endometrium and undergoes a degree of development in that location e.g. ovarian, tubal or abdominal pregnancy in humans (ectopic pregnancy). In false extrauterine pregnancy, occasionally in domestic animals, the embryo develop normal placental relationship with the endometrium and reaches a recognisable size before escaping from the uterine cavity into either the abdominal cavity (mummified) or the vagina. 3. Dropsy of the foetal membrane and foetus: This is a condition whereby fluid accumulates in the foetal membranes and or foetus. Thus we have such conditions as hydramnios, hydrallantois, oedema of the allantois-chorion and foetal anasarca (foetal oedema) with ascites/ hydrothorax. 4. Abdominal hernias: Cases of the pregnant uterus dropping into some hernias e.g. umbilical, perianeal, diaphragmatic or ventral hernias have been observed. Some of these may cause dystocia and result in the death of the foetus or dam or both. 5. Uterine torsion: This condition may occur in all species, but it is most commonly observed in dairy cattle and in advance pregnancy. Uterine torsion may be caused by unequal contraction of the uterus or by active movements of the foetus. If diagnosed early the foetus may still be alive. 6. Vagino-cervical prolapse: This also occurs in all species but most commonly in the cow/ewe. It is observed in the cow most commonly during the last 2 to 3 months of gestation when an increased amount of oestrogens are secreted by the placenta. These oestrogens cause relaxation of the pelvic ligaments and adjacent structures. If the cervix is relax and dilated abortion may occur. 7. Other conditions: Other causes of disturbances of pregnancy include (a) paraplegia or paresis during pregnancy. Other factors that leads to paraplegia or paresis include nutritional deficiencies e.g. phosphorus, calcium, trace elements such as copper, cobalt and iron, ketosis especially in ewe, lack of carbohydrates, grass tetany, parturient paresis and septic or infectious problems associated with advanced pregnancy. (b) haemorrhage in pregnancy. (c) rupture of the gravid uterus, etc. SIGNS OF PARTURITION: Some of the following signs may be observed before parturition -- 1. Relaxation of the pelvic ligaments (a) develops gradually during the last half of gestation due to the effect of oestrogens. Relaxin may also play a role. (b) Become more apparent during the last 24 to 48 hour. (c) Tail head appears elevated as the sacrosciatic ligaments and the coup muscle relax. 2. Relaxation of vulva and perineum (a) also a gradual process occurring simultaneously is the relaxation of the pelvic ligaments. (b) the vulva becomes 3 to 4 times larger than in non-pregnant state during the last 48 hours due to oedema. 3. Discharge from vulva (a) during the half of pregnancy a gum-like brown string hangs from the ventral comissure of the vulva. (b) as parturition approaches this mucous string changes colour to more greyish due to increased secretion by vaginal glands. (c) amount of discharge increases during the last 24-36 hour. 4. Oedema of the udder (a) also a gradual process. (b) maximal 24 to 36 hours prior to parturition. 5. Appearance of colostrum -- Usually within 24 to 36 hours before calving. 6. Behaviour. (a) May show restlessness. (b) seeking of seclusion. Initiation and control of parturition Gestation and the onset of parturition are entirely under hormonal control. The signal that initiates parturition begins in the foetus and evokes a response from the maternal endocrine system. The processes involved are as follows: a. There is maturation of the foetal hypothalamus/pituitary/adrenal axis b. Foetal hypothalamus stimulates foetal anterior pituitary to produce Adrenocorticotropic hormone (ACTH) c. ACTH stimulates production of cortisol by the adrenals d. Cortisol stimulates increased secretion of oestrogens and less progesterone by the placenta. The oestrogens are synthesized from progestagen precursors by activation of placental enzymes by cortisol. Concentration of cortisol in foetal plasma gradually rises beginning 10 to 15 days prepartum, rising more rapidly during the last 2 to 3 days of gestation. e. Oestrogens stimulates PGF2 alpha release from the endometrium and also enhances oxytocin attachment to the endometrium. f. Prostaglandin F2alpha causes luteolysis leading to decreased progesterone, release of oxytocin from the posterior pituitary, uterine contraction and relaxation of the cervix. g. Oxytocin -- from the posterior pituitary (Neurohypophysis) following distension of the vagina and cervix -- plays important part in the second stage of parturition. h. Relaxin -- from corpus luteum, -expansion of the birth canal, - released 2 days with peak at 14 to 22 hours before parturition. Requirements for normal birth 1. Maternal requirements - Normal physical condition. Good health and full physical maturity favour normal birth. - Normal size of the soft and bony birth canal - Normal relaxation of the soft and bony birth canal - Normal lubrication of the birth canal - Adequate expulsive forces i.e. uterine contraction and abdominal pressure 2. Foetal requirements - Normal size - Normal positioning - Normal form of foetus - Normal number of foetus 3. Dystocia Stages of Parturition: note that parturition is a continuous process and therefore these divisions are arbitrary. 1. First or dilation stage: This stage starts with the initial uterine contractions and is considered to be completed when dilation is complete, the foetus is positioned and the foetal parts first enter the vagina. Externally, the end of this stage is announced by the gushing of foetal fluids from the vulva following rupture of the foetal membranes. Contractions of the myometrium by the actions of PGF2 alpha and oxytocin force the foetal membranes against the softened cervix resulting in cervical dilation. The onset of this stage is rather difficult to determine as the external signs such as restlessness and colic are mild and transient and may escape notice. The length of this stage is highly individual. 2. Second or expulsion stage: This stage begins with the rupture of allantois and entry of foetal parts into the anterior vagina and ends with delivery. In addition to the uterine contraction abdominal press is brought into action by the entry of the foetus/membranes into the pelvic canal and the expansion of the soft birth canal by the entering foetus. This stage involves forcing of the foetus through the birth canal. 3. Third or expulsion of foetal membranes: This stage follows the expulsion stage and is completed when all foetal membranes are expelled. The approximate length of the stages of parturition are shown in the table below -- Table 2: Length of the stages of parturition +-------------+-------------+-------------+-------------+-------------+ | Animal | Dilation | Expulsion | Expulsion | Postpartum | | species | stage | stage | of | involution | | | | | membranes | (Days) | | | (Hours) | (Hours) | (Hours) | | +=============+=============+=============+=============+=============+ | Cow | 12-48 | 1-4 | 1-8 | 25-30 | | (Primiparou | | | | | | s) | | | | | +-------------+-------------+-------------+-------------+-------------+ | Cow | 3-8 | ½ -1 | | | | (Multiparou | | | | | | s) | | | | | +-------------+-------------+-------------+-------------+-------------+ | Mare | 1-4 | ½ -1 | ½ -3 | 13-25 | +-------------+-------------+-------------+-------------+-------------+ | Small | 2-6 | ½ -2\* | ½ -6 | 30 | | ruminants | | | | | +-------------+-------------+-------------+-------------+-------------+ | Sow | 2-12 | 1-5\* | ½ -12 | 20-30 | +-------------+-------------+-------------+-------------+-------------+ | Bitch | 2-12 | 3-6\* | \*\* | 30-35 | +-------------+-------------+-------------+-------------+-------------+ SIRE MANAGEMENT In a breeding centre or a herd of cattle, the bull is recognised as an important animal, and is often said to be half of the herd. A genetically proven or selected sire is a source of genetic improvement of livestock production either through artificial insemination or natural breeding. The semen from an outstanding, vigorous and healthy bull can be diluted and used to inseminate thousands of female cows owned by many farmers located in nearby or distant places. Such bulls can also serve about 30-35 cows in 10-12 weeks, and thus increasing the numerical strength of the herd. However, the full genetic potential of a bull cannot be realised unless the right housing, feeding, health service and other practices such as breeding soundness examinations are carried out. Selection of breeding bulls: the reason for this exercise is to ensure that only top quality sires are selected. This is necessary since they will be used in a large scale and their ability to transmit poor traits to their progeny is very important. Selection can be done by one of several methods. a. Pedigree selection: This is a selection based on the performance of the parents of the male b. Individual performance: This is a selection based on the performance of the male itself c. Progeny testing: This is a selection based on the progeny of the male. Although this method takes time to accomplish, it is the best/widely used. Housing: The main goal of housing for breeding bulls is for maximum survival of such valuable bulls without negative effect on growth/development. It is generally agreed that housing should be provided for breeding bulls and it should be made up of durable roof for protection from harsh and inclement weather, should have space for exercise with complete facilities for feed and water and protection of bulls. The wall should be made preferably of strong timber while the concrete floor should be supporting the shed to protect the bull against sunshine and rain. Adequate bedding of straw or haulms can be in the shed. Bedding absorbs urine, making it easier to handle. Each bull house should measure 400square feet. Feeding: Breeding bulls should be allowed to graze during the wet season. Grazing pasture is a much needed food for the animal and also ensures that the animal can exercise. Bulls should be provided supplementary concentrate feeds made up of maize and oil seeds (cotton seed or palm kernel cake, etc). A breeding bull needs 50% nutritive value of the body weight i.e. 2½ % of weight. This means that a 364kg bull will require 182kg of feed daily. Bulls should graze for at least 6-8hours and be supplemented with 0.9 to 1.8kg cotton seed cake ration. This will enable the bull to gain 0.45- 1.4kg body weight per day. Breeding bulls should be given 3.6-9.5kg hay per animal per day in addition to grazing and concentrate. Bulls should have access to clean and adequate drinking water at all times. They should also get mineral supplement (salt blocks). Breeding bulls should not be kept together with older bulls to avoid denying them access to concentrate. Poor feeding or grossly unbalanced ration may interfere with sperm output, quality and libido of bulls. Exercise: Exercise is vital to breeding bulls as this enables it to let off excess fat. Grazing in the field affords the bulls opportunity for exercise since grazing areas are usually large. It is recommended that feed/water should be placed at opposite sides of the field to ensure adequate exercise. Control of breeding bulls: The use of holding area within a bull pen is one of the ways of controlling bulls under intensive management. Bull paddocks should always be secured fenced to ensure adequate control of the animal. The bull attendants or handlers should have strong ropes and or halters for control of the bulls. Such handlers should be alert, smart and should enjoy their work. Usually a copper ring is inserted in the nose of bulls to enhance bull control. This is done by punching a hole in the septum with a special pair of pliers or some other sharp instrument after which a rope is attached. Dehorning or reduction of size of horns is recommended to prevent injuries. This is done by removing the horn-buds early in the life of the animal. Records: records are essential in assessing the potential of any breeding animal. A form for recording sexual data should include: tag number of the bull, date of collection, stimulus animal/location of situation, score or codified behavioural event, reaction time, ejaculate number, identity of semen collector and a space for additional remarks. Research has used the following codified behaviour system 0 -- No interest in stimulus situation 1 -- Sniffs or licks the stimulus but does not mount 2 -- Begins but does not complete a mount of the stimulus 3 -- Mounts the stimulus but dismounts without protrusion of the penis 4 -- Penis is covered with the AV but no ejaculation or ejaculatory thrust occurs 5 -- Ejaculation occurs in the absence of an ejaculatory thrust (no forward mount of rear feet) 6 -- Ejaculation occurs accompanied by a moderate forward movement of both rear feet. Ejaculation occurs accompanied by vigorous ejaculatory thrust (extreme dorsal curvature of the back) and marked forward mount and elevation of both feet off the ground. Separate sexual behaviour sheets for each bull should be maintained in a location which is convenient for examination by the semen collector. The semen collector should be in-charge of the collection team and should be responsible for bull identification, teaser selection and issuance of directives relating to positioning of the bull or stimulus animal. By examining the sexual behaviour records for a bull, the semen collector can determine if the reaction time was short during the previous semen collection, so that the same stimulus can be used or changed. Experience and examination of behaviour records often will enable a good semen collector to pick a stimulus situation which will be stimulatory to the bull. Consequently, if the initial selection is unsatisfactory a change should be made promptly. As a standing rule if a bull as not responded with a mount after 15 minutes in a given sexual situation the stimulus should be changed. Under other management plans, longer intervals can be tolerated, but the importance of constant introduction of novel stimulus situation can not be over emphasized. The sexual behaviour record is the prime working record for the semen collector. The semen data record is the other primary document of each bull's performance. The supervisor for semen production should ensure that these records are usually maintained in an up to date manner. Examination for venerally transmitted diseases: A protozoan parasite (Trichomonas foetus) and a bacterial organism (Campylobacter) are the two well known organisms that transmit veneral diseases in cattle. The disease are Trichomoniasis and Campylobacteriosis respectively. The manifestation of the diseases is observed only in infected cow or heifer. An infected bull is a potent source of infection of the female through mating, contact or via semen contaminated with the organism. Therefore it is extremely important to diagnose the disease particularly if irregular oestrus intervals, pyometra and early abortions have been recorded in breeding history. Diagnosis of these conditions involves prepucial washing, direct examination and culture. Other reproductive diseases include Brucellosis, Leptospirosis, Salmonellosis, Infectious bovine rhinotracheitis (IBR), Bovine virus diarrhoea/mucosal disease (BVD/MD), Para-influenza -3, G-up, Infectious (Contagious) bovine epididymitis, Vaginitis complex, Transmissible fibropapilloma/ epizootic bovine abortion, Endometritis, metritis/ pyometra. Irregular oestrous intervals, indicative of embryonic death might be caused by infections spread by the bull. Irregular intervals are observed in bovine Campylobacteriosis (Vibriosis) and Trichomoniasis. The external genitalia should be inspected/palpated for normal or abnormal conditions. This involves examination of the penis/prepuce for such conditions as prosthitis, balamitis, phimosis, paraphimosis, preputial abscesses, lesions and neoplasms. The testicles should be examined for asymmetry, orchitis, lesions, scar, etc. The scrotal circumference which is a strong index of sperm output should be taken. An ideal breeding bull should have a scrotal size of 30cm. It should also be palpated to examine the accessory sex organs. Mating behaviour/ability should be monitored as this affects semen quality. It involves sex drive or libido, a short preparatory stage ending in erection, mounting and grasping of the mount, short thrust in search of the vagina and the final powerful ejaculatory thrust. If no attempt to mount is made after 15 minutes the bull's ability to serve becomes questionable. A normal bull mounts readily and does not support himself on the stimulus animal (mount or teaser). **APPLICATION OF COMPUTER IN REPRODUCTIVE DATA MANAGEMENT** Management of reproduction requires a mixture of science, technology, and the art of animal husbandry. Reproductive data management is directly proportional to reproductive efficiency, and has profound effects on production efficiency, profitability, and sustainability of commercial livestock production. Optimal reproductive efficiency requires excellent management of reproduction, feed, environment, etc. Managing data as a resource is an important managerial task in any organisation including livestock as poor data management will lead to inefficient farming. The computer is an electrical machine capable of receiving, storing, retrieving as well as analyzing data into various forms/media. The advent of new generation of powerful but robust and inexpensive microcomputer means that an animal scientist now have ample facilities to collate, enter, check, analysed and store vast amount of data on animal production, reproduction, nutrition, health as well as generating reports in the format required for end-users to aid management decision making. Computer was first used as a management tool in recording milk services by the dairy herd improvement (DHI) association. It is presently being use in analyzing reproductive data to compare fertility of bulls, age of attainment of puberty, age at first calving, non-return rates (60 or 90days) to estimate conception, services per conception, calving, oestrus, pyometra, abortion, repeat service (13 month calving intervals for primiparous cows and 12 month calving intervals for multiparous cows. The DHI program was tailored towards the unique individual animal identification with records to provide information to farmers on the individual cow production for intended decisions on feeding, management and culling. These records are maintained in large centralized mainframe computers with databases to provide information for artificial insemination industry to develop sire proofs/aid in genetic selection programs. The information generated is therefore a management aid to dairy producers and also help to provide a large research database to develop new techniques. Herd Accumulator (Herd management Software): it consists of a computer which works as data accumulator. The computer is loaded with the specific software that allows communication with the readers. Herd management software provides mechanisms for farmers to store individual cow data into a database. Data can be entered into these software applications manually via an easy to use, standardized interface, or alternatively through digital devices such as milk meters, cow weight scales, etc linked to the database. This herd management software provides devices with the information required to make decision or conduct an action. Automatic Milking: this is the extraction of milk from dairy animals with the use of electromechanical instruments that clean udder, attaches its cup to the teat and provide the pulsatile pressure for milk letdown, as well as passes it to the required containers where further processing take place without any human labour. It gives the farmer more time to focus on other management issues such has feeding, breeding, health and hygiene. Automated Oestrous Detector: Numerous physiological/behavioural changes are associated with oestrus and various approaches to utilize these changes to automate oestrus detection have been explored. These include activity monitoring systems (pedometers or accelerometer technologies), mount detectors in which pressure-sensors are placed on the cow's tail head and are stimulated each time the cow is mounted, changes in temperature, vaginal mucus resistance and changes in hormones such as milk progesterone, lying behaviour/ rumination time. These measures are used in the formulation of oestrus detection algorithms. These devices are either leg or collar mounted with a camera based system that automates the inspection of heat patches. All automated monitoring systems include electronic identification for oestrus cows to be automatically drafted using alert data. For example 'Reprotech' is an oestrus detection device to detect cows that stands for mounting, once a cow mounts another cow, the transmitter is depressed and a signal is sent to a receiver with the date, time and duration of mount which is later sent to the main computer for evaluation/decision.