MAJOR DISEASES OF CATTLE AND ITS MANAGEMENT:

July 26, 2019

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Cattle are susceptible to a wide variety of infectious diseases. Susceptibility has increased with the introduction of exotic germplasm and climate changes. The important infectious diseases of the cattle and its control are:

Foot and mouth disease:

It is a highly infectious and contagious viral disease of all cloven footed domesticated and wild animals. The infection imposes a high spread during the cooler season when the air remains in damp condition.

Vaccination is the only means to control the disease.

Vaccine	Age	Dose	Booster	Interval	Season
FMD	6-8 wks	10 ml s/c	6, 9 or 12 months	Annual	Preferably November, December

Black Quarter

Black Quarter is one of the deadly bacterial diseases of cattle. The disease spreads rapidly after heavy rainfall by contamination of soil with spores of the organism. Areas where previous death occurs from clostridium infection, have a higher incidence or risk of disease because of increased environmental contamination. Treatment of the disease with specific antibiotic is useful if the diagnosis of the disease can be made at the early stage.

The disease can be controlled by regular vaccination.

Vaccine	Age	Dose	Booster	Interval	Season
Polyvalent B.Q. Vaccine	All age	5 ml s/c	6 months	Annual	Before onset of monsoon, all season in endemic areas

Haemorrhagic septicaemia:

Haemorrhagic septicaemia, as the name implies is a poisoning of the blood accompanied by internal haemorrhages, is an acute septicaemic disease caused by a bacterium, Pasteurella multocida. The incidence of H.S. is throughout the year. The outbreak is not only in the period of high humidity or monsoon but also in winter season. Highest number of outbreaks during high humid and rainy season as compare to winter season. Although antibiotics are available for the treatment, there may not be any time for treamtn in most cases.

The disease may be controlled by regular vaccination.

Vaccine	Age	Dose	Booster	Interval	Season
H.S. adjuvant vaccine	All ages	3 ml i/m	6 months	Annual	Preferably in May/June

Brucellosis:

Brucellosis is one of the major zoonotic diseases and causes great economic losses due to loss of milk production, abortion at late pregnancy and high rate of infertility in females and varying degree of sterility in males. There is no seasonal variation for occurrence of the disease. Regular screening of serum samples for detection of the disease is required. Incidence of brucellosis can be reduced by elimination of infected bull, isolation and treatment of positive reactors and calfhood vaccination.

Brucella is one of the world’s major zoonotic pathogens, and is responsible for enormous economic losses as well as considerable human morbidity in endemic areas.

Pathogenesis :

Brucellosis is a sub-acute or chronic disease which may affect many species of animals. In cattle, sheep, goats, other ruminants and pigs the initial phase following infection is often not apparent. Brucella has predilection for the pregnant uterus, udder, testicle and accessory male glands, lymph nodes, joint capsules and bursae. In sexually mature animals the infection localizes in the reproductive system and typically produces placentitis followed by abortion in the pregnant female, usually during the last third of pregnancy, and epididymitis and orchitis in the male. Lesions consist of necrotic placentitis and interstitial mastitis in pregnant cows, and fibrinous pleuritis with interstitial pneumonia in aborted fetuses and newborn calves. The recently recognized types associated with marine animals may also have the capacity to cause human disease.

How to diagnose?

Diagnosis can only be confirmed by laboratory tests. The isolation and identification of Brucella offers a definitive diagnosis of brucellosis and may be useful for epidemiological purposes and to monitor the progress of a vaccination programme in animals. The RBPT, tube agglutination and ELISA procedures are recommended. Culture of Brucella from abortion material, milk or tissues collected at autopsy provides a definitive diagnosis.

Facilities for diagnosis of brucellosis are available at ICAR Research Complex for Goa.

Differential diagnosis :

Brucella abortions should be differentiated from septic abortion, abortion from other infectious agents such as listeriosis, Q fever, leptospirosis, campylobacteriasis, trichomonads, fungi, epizzotic viral abortion and infectious bovine rhinotracheitis.

Impact of the problem:

Expansion of animal industries and urbanization, and the lack of hygienic measures in animal husbandry and in food handling partly account for brucellosis remaining a public health hazard. Expansion of international travel which stimulates the taste for exotic dairy goods such as fresh cheeses which may be contaminated, and the importation of such foods into Brucella-free regions, also contribute to the ever-increasing concern over human brucellosis. Sexual transmission and/or artificial insemination are also important.

The disease is of zoonotic importance.

Treatment:

Treatment for brucellosis in animals is neither advisable nor practicable.

In humans :

Treatment of uncomplicated cases in adults and children eight years of age and older: doxycycline 100 mg twice a day for six weeks + streptomycin 1 g daily for two to three weeks.

Doxycycline 100 mg twice a day for six weeks + rifampicin 600–900 mg daily for six weeks.

Control and Prevention :

Animal brucellosis is best prevented by careful herd management and hygiene.
Vaccination is useful for prevention and control of infection.
B. abortus strains 19 and RB 51 are recommended for prevention of bovine brucellosis.
B. melitensis Rev 1 is recommended for prevention of B. melitensis infection in sheep and goats.
Control and prevention schemes require effective collaboration between all sections of the community.
Education and information programmes are essential to ensure cooperation at all levels in the community.
Effective preventive measures and control of animal movements are essential.

Listeriosis :

Listeriosis is an important bacterial infection, which occurs in an array of animals including humans. It arises mainly from the ingestion of contaminated food. Listeriosis leads to septicaemia, abortion, stillbirth and menigoencephalitis.

Pathogenesis :

Ingestion of Listeria from food –> Intestine –> Mean incubation period: 31 days –> L.monocytogenes crosses mucosal barrier –> Bloodstream –> Hematogenous dissemination –> Brain, placenta and other sites.

How to diagnose?

The disease can be tentatively diagnosed on the basis of clinical signs and symptoms. Its confirmation is achieved by isolating the pathogen from clinical specimens, such as blood, cerebrospinal fluid (CSF) and the muconium of the newborn or foetus in abortion cases, and from faeces, vomitus, food stuffs/animal feed and/or vaginal secretions of infected individuals.

Differential diagnosis :

Listeriosis has been difficult to diagnose as it can easily be confused with the nervous form of acetonaemia in cattle, early cases of pregnancy toxaemia in sheep, rabies and encephalitis of viral origin. Listerial abortion must be differetaited from other causes of abortion like brucellosis, leptospirosis and trichomonads.

Impact of the problem :

The spectrum of the disease in animals is broad ranging from asymptomatic infection and carriage to uncommon cutaneous lesions or various focal infections such as conjunctivitis, urethritis, endocarditis, and severe disturbance of the gait, followed by death. Abortions and perinatal deaths are common in cattle and sheep. L. monocytogenes is a well-recognized cause of mastitis, abortion, repeat breeding, infertility, encephalitis and septicaemia in cattle.

Listeriosis is an important bacterial zoonosis which occurs in a variety of animals including humans, and arises mainly from the ingestion of contaminated food and water. Listeriosis is a serious invasive disease which leads to septicaemia, abortion, stillbirth, meningitis and meningoencephalitis, especially in immunocompromised individuals and in persons in contact with animals.

The prevalence of listeriosis is decidedly more among the individuals with immunocompromised status, young age groups, elderly people and persons who are immunosuppressed due to medication and/or illness.

Treatment:

Ampicillin, amoxicillin, tetracyclines, chloramphenicol, trimethoprim and sulphamethoxazole are recommended. Ampicillin is the drug of choice in cases of encephalitis. Ampicillin along with gentamicin are recommended for prolonged treatment regimes.

Control and Prevention

Culling infected animals should be advocated as they secrete the organisms in secretions and excretions, especially in the cases of mastitis.
Care in the use and preparation of silage is important as the pathogen grows luxuriantly at a pH greater than 5.
So far no vaccine is available against listeriosis.
Listeriosis can be prevented in humans by taking care during handling of the abortion cases in both humans and in animals, avoiding consumption of contaminated food-stuffs and avoiding cross-infections especially among infants in hospitals.

Mastitis :

Mastitis or inflammation of mammary gland or udder is an economically important condition in milking animals. Mastitis is a disease that affects a large number of dairy cattle throughout the world. It may affect one or all quarters of the udder. It is manifested in the form of swelling of the affected quarters, change in milk colour and composition.

Pathogenesis

Development of mastitis is complex and involves three stages: invasion, infection and inflammation. The factors which contribute to the causation of mastitis include-

v Contamination with milker’s hands, contaminated floors, utensils and clothes.

v Presence of high population density of the causative bacteria in milking shed.

v Damage to the teat sphincter.

v Udder infected with FMD, Pox virus.

v Physical trauma that may accelerate the growth of these causative bacteria.

v Sawdust and shaving used as bedding, which are harboring E. coli and Klebsiella pneumoniae.

v Edema and congestion of udder during parturition.

v Poorly designed housing, uneven faulty surface.

v Dirty milking machine.

How to diagnose?

Clinical signs, palpation of udder, monitoring the milk consistency may give clue about causation of mastitis. Diagnosis of mastitis is based on bacteriological and cytological methods of examination. Subclinical cases may go unnoticed and therefore testing of milk with California mastitis test (CMT) or any other spot test is necessary. Bacteriological examination of CMT positive samples should be carried out.

Impact of the problem

If one quarter is affected by mastitis, 25% milk yield is lost permanently. It may also spread to other quarters, hence it causes major economic losses to the farmer. High yielding animals are more prone to this condition, if not milked properly. The milk from infected udders contributes to high microbial counts of milk, which in turn is not suitable for preparation of milk products. Mastitic organisms are also pathogenic for human beings. Mastitis control is prerequisite to any of the clean milk production programmes.

Treatment

Udder infusion:. Disposable tubes with water soluble ointment base need to be used. Emptying of udder is essential before infusion. For animal with clinical mastitis manual removal of congestion in the gland and inflammatory debris from the duct system should be done.
Parental treatment is advisable. Before antibiotic therapy, the sensitivity of the pathogens to particular antibiotics should be carried out.
The use of preparations containing disinfecting ingredients and added emollients is effective which promote the healing of teat lesions and prevent new infections.

Iodophors are important teat dips. Application of preparations containing 3-5000 mg. available iodine per kg, depending on the glycerin concentration, leads to reduction in bacterial numbers.

Culling of cows with therapy resistant udder diseases.
If machine milking is practiced then rinsing of the teat cups and dipping them in the disinfectant wash water between cows, by dipping a pair of each cluster in turn or hot water (170°-180°) for 10 sec. is effective.

In case of dry cows, infusion at the time of the last milking or at the beginning or end of the dry period is recommended.

Control and Prevention

Mastitis control also entails a good understanding of the factors that encourage its incidence and the microorganisms that cause it.
Mastitis control must be concentrated on the prevention aspects, which depends mainly on the whole hygienic management and absence of stress conditions.
Estrogenic compound in foods should be reduced. Young animals should be milked before older. Newly introduced animal should milked separately.
Specific control measures need to be taken according to the respective cause and the extent of losses. Specific control measures include –