RAT-COMMON-DISEASES (1).pptx

RAT BY: BERMUDEZ, CROOC, PARAS, PALADAN  LEARNING OBJECTIVES Objective to learn about this is to acquaint basic knowledge of the variety of infectious agents that may infect rats and to ensures a quick and appropriate response to control the disease out break i...

RAT BY: BERMUDEZ, CROOC, PARAS, PALADAN  LEARNING OBJECTIVES Objective to learn about this is to acquaint basic knowledge of the variety of infectious agents that may infect rats and to ensures a quick and appropriate response to control the disease out break in colonies.  INTRODUCTI ON LABORATORY RAT Laboratory Rat is used as a animal modal in studies of nutritional behavioural ,toxicity and cancer DISEASES studies. Any condition that impairs the normal functioning of the body which is typically manifested by distinguishing signs and GENERAL PREVENTIVE AND CONTROL MEASURES OF DISEASES Laboratory rodents that are disease- and pathogen-free: Procuring such animals from high-quality sources Transporting them in filtered shipping containers Maintaining them in facilities with both physical and procedural barriers to the introduction of infectious agents are effective measures to prevent disease within a colony that may confound or ruin experiments. GENERAL PREVENTIVE AND CONTROL MEASURES OF DISEASES CAGES Static microisolation (filter top) cages and more advanced individually ventilated caging systems have been used widely for rodent housing to impede cage-to-cage transmission of infectious agents. TEMPERATURE Temperature should be maintained at 68°–79°F (20°– 26°C) , Relative humidity should be maintained at 30%– DIET70% , Ventilation rates should be 10–15 fresh air changes/hr. Provision of autoclaved or irradiated diets, Highly purified, deionized, acidified, chlorinated, or sterile water. GENERAL PREVENTIVE AND CONTROL MEASURES OF DISEASES SANITATION OF ENCLOSURE Heating cages and other equipment to 180°F (82.2°C) or using appropriate chemical disinfection (eg, hypochlorite solutions) kills nonspore-forming pathogenic bacteria and viruses. All caging and other equipment should be rinsed thoroughly after treatment with detergents or disinfectants. Bedding material should be disposed by incineration. QUARANTINE Quarantine is required for all rodents coming from non_commercial sources. The quarantine process takes at 8 Weeks or more weeks before all test results have been received. RAT DISEASES  RAT DISEASES 1)Bacterial diseases and Mycoplasmal 2)Fungal/Mycotic Diseases 3)Viral Diseases 4)Parasitic Diseases 5)Neoplasia 6)Miscellanious conditions BACTERIAL AND MYCOPLASMAL DISEASES  MURINE RESPIRATORY MYCOPLASMOSIS(MRM) Murine respiratory mycoplasmosis (MRM), also known as chronic respiratory disease (CRD) of rats, is a common infectious disease of the respiratory tract in laboratory and pet rats caused by the bacterium Mycoplasma pulmonis. It's important to note that wild rats can also be carriers  SYMPTOMS: MRM can be asymptomatic, particularly in young animals. However, when symptoms do occur, they can vary depending on the severity of the infection and the presence of other concurrent diseases. Here are some common signs: Respiratory: Difficulty breathing (dyspnea), labored breathing (rales), wheezing, snuffling, chattering Ocular and Nasal Discharge: Red-tinged discharge around the eyes and nose (may be porphyrin, a red pigment secreted by the harderian gland, not blood) Head Tilt: Due to inner ear infection in some cases Weight Loss: In severe cases TRANSMISSION Mycoplasma pulmonis is a highly contagious bacterium spread through direct contact with infected rats or aerosols containing the bacteria. This can occur through: Nose-to-nose contact Sharing contaminated bedding or food Transmission from mother to offspring (vertically) in some cases RISK FACTORS Several factors can increase a rat's susceptibility to MRM, including: Age: Older rats are more likely to develop clinical signs. Stress: Stressful conditions can weaken the immune system, making rats more susceptible to infection. Poor Environmental Conditions: Overcrowding, inadequate ventilation, and improper sanitation can contribute to the spread of disease. Concurrent Infections: Presence of other respiratory DIAGNOSIS Diagnosing MRM can be challenging due to the variability of symptoms and the potential for overlapping conditions. Veterinarians may use a combination of methods, including: Physical examination: Listening for abnormal lung sounds and examining for respiratory distress. Microscopy: Analyzing respiratory secretions for the presence of Mycoplasma pulmonis. PCR testing: A more sensitive method to detect the bacteria's genetic material. Radiography (X-rays): May reveal lung abnormalities in severe cases. TREATMENT There is no cure for MRM; however, treatment can help manage symptoms and improve the quality of life for affected rats. Treatment options may include: Antibiotics: Antibiotics like enrofloxacin or tylosin are sometimes used to manage the bacterial infection. However, Mycoplasma pulmonis can develop resistance to antibiotics. Anti-inflammatory medications: To reduce inflammation in the airways. Supportive care: Maintaining optimal environmental PREVENTION Prevention is crucial in controlling MRM outbreaks in rat colonies. Here are some key measures: Purchasing rats from reputable breeders: Look for breeders who practice SPF (Specific Pathogen Free) or HRM (Health-Restrained Microflora) protocols. Quarantine new arrivals: Isolate new rats for at least 2-3 weeks to monitor for signs of illness before introducing them to the main colony. Maintaining a clean environment: Regular cage cleaning, proper waste disposal, and disinfection of equipment. Good ventilation: Maintain proper airflow to prevent ammonia build-up and reduce the spread of airborne pathogens. Minimizing stress: Provide enrichment activities and spacious enclosures NEOPLASIA NEOPLASIA Tumors (neoplasias) are growths that we, as rat owners, see all too often. Learning about the different types of cancers will help us to identify problems as they occur, treat sooner, and better understand the disease processes involved. Any abnormal growth, swelling, bump, or lump on your rat can be a potentially serious issue. Rats have a high metabolism and a relatively short life span compared to many other pets. KERATOACANTHOMA Keratoacanthoma (KA): a low grade growth of the epidermis that originates in the hair follicle and progresses rapidly. Also referred to as: “self-healing,” or “pseudocarcinoma.” ETIOLOGY Keratoacanthoma is a typically benign epidermal tumor that may resemble squamous cell cancer both visually and histologically. But unlike squamous cell cancer, it is usually benign. This type of lesion often forms a keratin horn that gives it a characteristic appearance. Factors that may contribute to KA include: Immunocompromised status Trauma Genetic predisposition A keratoacanthoma may occasionally progress to multiple growths, may enlarge, may become aggressive locally. However, metastasis to distant organs is very rare. The cause of keratoacanthomas is unknown. Prognosis and outcome for a rat diagnosed with keratoacanthoma PATHOLOG Y Keratoacanthoma is a crateriform squamous lesion of the sun-exposed skin of an animal that typically grows rapidly then involutes. Microscopically, keratoacanthoma shows three distinctive growth phases including: the early growth phase; fully developed/proliferative phase; and senescent/regressive phase. 1 Most keratoacanthoma are biopsied in the fully developed/proliferative phase which is histologically characterized by a symmetric crateriform, exo- endophytic lesion with buttress formation and a prominent central keratin plug. Invasive lobules and nests of tumor cells with low-grade nuclei and abundant, glassy eosinophilic cytoplasm that mature toward the center are characteristic. Keratoacanthoma usually shows a sharp delineation between the tumor nests and stroma and can entrap elastic fibers. A prominent associated mixed inflammatory infiltrate of lymphocytes, eosinophils, and neutrophils is frequent. CLINICAL SIGNS KA presents with a characteristic appearance of a crateriform lesion, a central keratinous plug, and edges of normal skin extending over the central keratinous crater. DIAGNOSIS Exact diagnosis can be performed by biopsy and pathological examination. TREATMENT Keratoacanthomas can be surgically removed, but is often known to involute and resolve spontaneously. While this type of tumor does tend to resolve on its own after several weeks to months (spontaneous involution), the resulting wound may sometimes require suturing, and may or may not leave a scar. Although lotions and ointments do not help to resolve this growth, if surrounding tissue is cracked, irritated or inflamed, the vet may choose to treat with applications of an antimicrobial ointment. If the decision is made for surgical intervention, the procedure may be one of surgical excision, cryosurgery (a controlled type of tissue freezing), or electrocautery, depending on the location and involvement of the growth. In the event of surgery, the inclusion of a post-op broad-spectrum NURSING CARE Keep the area of growth clean. Apply any ointments your veterinarian may prescribe. Provide a hospital (small, one-level) cage during recovery, or if there are concerns that cagemates may groom sutures or wound site. Provide clean bedding daily such as felt, soft t-shirt type material or ink- free paper towels. Avoid using material such as terry cloth type towels that can ravel. Also avoid litter-type bedding, post-op, until healed to prevent the chance of wound contamination or infection. Provide additional warmth to maintain body temperature within normal limits. It is essential that the rat does not become overheated or dehydrated. The rat should also be able to move away from the heat PREVENTION Keep the area of growth clean. Apply any ointments your veterinarian may prescribe. Provide a hospital (small, one-level) cage during recovery, or if there are concerns that cagemates may groom sutures or wound site. Provide clean bedding daily such as felt, soft t-shirt type material or ink- free paper towels. Avoid using material such as terry cloth type towels that can ravel. Also avoid litter-type bedding, post-op, until healed to prevent the chance of wound contamination or infection. Provide additional warmth to maintain body temperature within normal limits. It is essential that the rat does not become overheated or dehydrated. The rat should also be able to move away from the heat TREPTOCOCCUS PNEUMONIA ETIOLOG Y Streptococcus pneumoniae is a bacterium with the following synonyms: Diplococcus pneumoniae, Pneumococcus pneumoniae. An encapsulated, Gram positive, lancet-shaped diplococcus. Although found mainly in pairs, the organism may occur in short chains or singly. As cultures age they become Gram negative HOSTS Humans are the main natural host. Between 40% and 70% of normal human adults carry one or more serologic types of pneumococci in their throats. Severe epizootics have been reported occasionally in rats, TRANSMISSIO N Host sites of greatest  predilection for the infection are nasal passages and middle ears. The carrier state is common in infected colonies. Transmission is mainly by aerosol. The  organism can remain viable for days on fomites, but fomites are of doubtful PATHOLOGY Pneumococcal capsules consist of large polysaccharide polymers that form hydrophilic gels on the surface of the microorganisms. Only encapsulated strains are pathogenic. The organism spreads from nasopharynx to lungs in rats or man. Infection becomes established in a SIGNS Clinical signs can include general ill rodent signs, such as hunched posture, ruffled fur, inappetence, or death with no premonitory signs, or specific signs such as nasal discharge, conjunctivitis, and vestibular signs. In guinea pigs, stillbirths and abortions are part of the clinical presentation On necropsy, a serosanguineous to purulent exudate is often found in the nasal cavities and the tympanic bullae. The lungs can have areas of firm, dark red consolidation. Fibrinopurulent pleuritis, pericarditis, DIAGNOSIS Confirmation of the diagnosis is via culture of lesions or affected tissues. S. pneumoniae grows best on 5% blood agar and is alpha-hemolytic. The organism is then presumptively identified with an optochin test. PCR assays are also available for diagnosis. PCR- based screening for S. pneumoniae may be conducted on respiratory samples or feces. PCR may also be useful for confirmation of presumptive microbiologic identification or confirming the identity TREATMENT & CONTROL To prevent transmission of S. pneumoniae to animals, the animals must be raised in strict bioexclusion housing, such as rodent S. pneumoniae probably originates from humans, animal care workers should wear Masks and use other standard PPE to reduce the chance of contaminating the animals. Caretakers with pneumococcal pneumonia, otitis media, conjunctivitis, or other diagnosed or possible streptococcal infections should not work with animals until a course of antibiotics has been completed.  Normal animal work precautions will prevent humans TREATMENT & CONTROL S. pneumoniae are susceptible to most common disinfectants used in animal facilities. Any chemical or mechanical sterilant will also serve to remove S. pneumoniae from the environment. Treatment of animals with antimicrobials may serve to treat illness, but rarely, if ever, resolves the carrier state, nor will antibiotic treatment eliminate bacteria from the bedding or cage surfaces. Thus, treatment is only recommended to ameliorate clinical signs. Human isolates of S. pneumoniae are often multi-drug resistant. To obtain a CORYNEBACTERIUM Corynebacterium kutscheri ETIOLOG Classification Y Gram-positive, small, rod-shaped bacterium Family Corynebacteriaceae Affected species Rats, mice, hamsters. Possibly all laboratory rodents, but not described in gerbils, and only described once in guinea pigs. Frequency Rare in laboratory colonies. Described as a natural infection in R. norvegicus, but prevalence in wild and pet populations unknown. TRANSMISSIO N C. Kutscheri is probably primarily fecal-oral. In experimental infections, animals can shed bacteria in feces for up to 5 months, and infection is persistent; animals do not clear the infection. Different strains of mice vary in susceptibility to both colonization and disease development in mice. Sex also plays a role; male mice appear to be more susceptible to disease and to carrier PATHOLOGY Active disease characteristically begins as a septicemia which results in lodgement of septic emboli in many organs, most notably: In mice, kidney and liver, less frequently in lungs, skin and joints In rats, the lungs. Subsequent expansion from the initial embolic foci in the lungs CLINICAL SIGNS & Inapparent infection is common. LESION Animals can harbor C. kutscher in the oral cavity, cervical lymph nodes, and gastrointestinal tract with no ill effects. With advancing age, stress, experimental manipulation, or any derangement of the immune system, hematogenous spread may occur. When clinical signs occur, they are nonspecific general signs of illness - weight loss, ruffled fur, and, in rats, respiratory distress and DIAGNOSIS Culture methods give inconsistent results  and are not reliable for routine purposes. The  agglutination reaction, indirect fluorescent antibody technique, and agar- gel immunodiffusion methods are unsatisfactory for the detection of subclinical infections. The C. kutscheri ELISA holds great promise  TREATMENT & C. kutscheri is susceptible to most common disinfectants used in CONTROL animal facilities. Any chemical or mechanical sterilant will also serve to remove C. kutscheri from the environment. C. kutscheri has been isolated from seawater, and can survive up to 8 days at 4°C in PBS. Treatment of animals with antimicrobials may serve to treat illness, but would probably not resolve the carrier state, nor will antibiotic treatment eliminate bacteria from the bedding or cage surfaces. Treatment is only recommended to ameliorate clinical signs if necessary for rederivation. Treatment of animals for C. kutscheri has not been reported. C. bovis isolates have been shown to be sensitive to tetracycline, DERMATOPHYTOSIS RINGWORM ETIOLOG The set of fungi that cause ringworm Y in rats called are from a class of fungi deuteromycetes, with Tricopyton mentragrophytes being the primary fungus that is responsible for cases HOSTS Humans are the main natural host. Between 40% and 70% of normal human adults carry one or more serologic types of pneumococci in their throats. Severe epizootics have been reported occasionally in rats, TRANSMISSIO N Host sites of greatest  predilection for the infection are nasal passages and middle ears. The carrier state is common in infected colonies. Transmission is mainly by aerosol. The  organism can remain viable for days PATHOLOGY Ringworm infection often spreads through direct contact with infected animals or humans, but it may also be spread via contaminated CLINICAL SIGNS Usually rats that are infected by the ringworm fungus never show symptoms apart from the skin lesions, which will vary from mild spots of hair loss to marked hair loss with thick scaly skin. Other symptoms may include: Reddened skin Irritated skin  DIAGNOSIS Physical exam on your rat, taking into account the background history of symptoms and possible incidents that might have led to this condition, such as contact with other animals, or even with other people. A microscopic examination of skin scrapings taken from the infected area TREATMENT & Locally applied and oral fungicidal and CONTROL antibiotic medications, both of which have the ability to kill fungi. Topical lotions and medicated shampoos for completely healing your rat. Infected rats should be isolated from other rats in the group to prevent the spread of ringworm infection to healthy rats. To prevent spreading ringworm infection by maintaining good hygiene of your rat's cage  THANK YOU! I hope you learn something new today! https://nap.nationalacademies.org/read/1429/chapter/9#54 https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/corynebacterium-kutscheri https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/corynebacterium-kutscheri https://www.petmd.com/exotic/conditions/skin/c_ex_rt_ringworm https://www.criver.com/sites/default/files/resources/doc_a/CorynebacteriumkutscheriTechnicalSheet.pdf https://www.google.com/url?sa=i&url=https%3A%2F%2Fletslovechinchillas.weebly.com%2Fringworm.html&psig=AOvVaw12d7EEubTJlZBqWjebVMp 1&ust=1713788034120000&source=images&cd=vfe&opi=89978449&ved=0CBAQjRxqFwoTCOD6hZqk04UDFQAAAAAdAAAAABAU