Most Common Infectious Cattle Diseases

Cattle health is crucial for successful dairy and beef operations. Infectious diseases in cows can lower milk production, cause infertility, result in calf losses, and even lead to death. This negatively impacts farm profitability.

According to the USDA, infectious diseases account for over half of all calf mortality. Veterinary care and treatment of ill cattle also generate additional costs for cattle producers.

Understanding the most common infectious cattle diseases, their transmission, symptoms, and prevention methods is key to safeguarding your herd. In this article, we are going to discuss the most prevalent infectious cattle diseases to be aware of.

Bovine Viral Diarrhea (BVD)

Bovine viral diarrhea is a widespread viral infection of cattle that can cause gastrointestinal, respiratory, and reproductive problems. There are two strains of the BVD virus – BVDV 1 and BVDV 2.

Transmission: The BVD virus is spread through direct contact with infected cattle or indirectly through contaminated equipment and facilities. The virus can also be transmitted from cow-to-calf during pregnancy.

Symptoms: Diarrhea, fever, runny nose, coughing, reproductive issues like infertility and calving problems are symptoms. BVD can also result in the birth of persistently infected calves.

Prevention: Testing and culling persistently infected animals, quarantining new arrivals, vaccination, and biosecurity measures help control BVD. Avoiding contact with outside cattle can prevent infection.

Bovine Respiratory Disease (BRD)

Bovine respiratory disease is the most common and costly illness affecting cattle in the US. BRD typically occurs when stress and viral infections compromise the immune system, allowing bacterial invasion of the lungs.

Transmission: Infectious agents are spread through aerosol transmission from infected cattle. Risk factors like transport stress, poor ventilation, and crowding facilitate transmission.

Symptoms: Breathing difficulty, fever, coughing, nasal discharge, depression, loss of appetite. Calves may drool, stretch their necks out, or breathe with an open mouth.

Prevention: Reducing stress, proper ventilation, vaccination, antibiotics, and separating sick animals are key prevention measures. Good colostrum intake boosts calf immunity against BRD.

Bovine Tuberculosis

Caused by Mycobacterium bovis, bovine tuberculosis is a chronic bacterial disease that affects the lymph nodes and respiratory system of cattle.

Transmission: Airborne spread through coughing and sneezing by infected cattle. The disease can also spread through ingestion of contaminated milk or feed.

Symptoms: Weight loss, fever, weakness, coughing, enlarged lymph nodes. Lesions may be observed in the lymph nodes, lungs, intestines, liver, and other organs.

Prevention: Testing and culling infected cattle. Pasteurizing milk also kills TB bacteria. Restricting contact with wildlife reservoirs of TB helps prevent transmission.

Brucellosis

Brucellosis is a contagious zoonotic bacterial disease that mainly affects the reproductive system of cattle. It is caused by various Brucella species.

Transmission: Spread through aborted fetuses, placentas, calving fluids, milk, urine, and reproductive discharges from infected cows. Indirect spread through contaminated feed, water, and facilities also occurs.

Symptoms: Abortions and stillbirths are the hallmark signs in cows. Infertility, fever, reduced milk yield may be observed. In bulls, orchitis and epididymitis occurs.

Prevention: Vaccination of calves between 4-12 months using RB51 or S19 vaccine. Testing and culling seropositive cattle. Pregnant cattle should not graze with infected herds. Proper containment and disposal of aborted fetuses, placentas, and uterine discharges from cattle.

Johne’s Disease

Caused by Mycobacterium avium subspecies paratuberculosis, Johne’s is a contagious bacterial disease that infects the intestines of ruminants like cattle.

Transmission: Fecal-oral route. Calves under 6 months are the most susceptible and commonly get infected by ingesting manure from infected cows.

Symptoms: Diarrhea, rapid weight loss, and protein loss despite a normal appetite. This wasting away is due to malabsorption caused by the damaged intestines.

Prevention: Management strategies to prevent fecal contamination like colostrum pasteurization, clean calving areas, reduced cow density, and manure management. Vaccination may help reduce clinical signs.

Bovine Leukosis Virus

Bovine leukosis is a retroviral disease of cattle characterized by immune deficiency and tumor development in infected animals.

Transmission: The bovine leukemia virus (BLV) is spread through transfer of infected lymphocytes via blood on needles or dehorning equipment. BLV infected colostrum and milk can also transmit infection.

Symptoms: Persistently increased lymphocyte counts, enlargement of lymph nodes, weight loss, and development of lymphosarcoma tumors internally are common clinical signs.

Prevention: Segregation and culling of seropositive cattle, avoiding shared needles between cattle, pasteurizing milk from infected cows, and vaccination. Testing the herd and not introducing infected cattle prevents spread.

Foot and Mouth Disease

Considered one of the most contagious livestock diseases, FMD is a severe, clinically acute viral disease of cloven-hoofed animals like cattle, swine, sheep, and goats.

Transmission: The FMD virus spreads rapidly through direct contact, contaminated objects, aerosolized droplets, and airborne transmission. Recovered animals can be carriers of FMD.

Symptoms: Fever, blister-like lesions in the mouth, feet, and teats are characteristic. Salivation, lameness, weight loss, and drop in milk production may occur.

Prevention: Strict biosecurity. FMD viral strains are not found in the US, and vaccination is applied after outbreaks in FMD-free regions. Culling infected and exposed herds helps control spread. Quarantines and animal movement standstills are also implemented.

Conclusion

Infectious diseases can have a devastating impact on cattle health and farm economics. By learning the main transmission routes, clinical signs, and prevention strategies for common cattle diseases, producers can take proactive steps to safeguard their herds.

Measures like biosecurity, testing, vaccination, isolation of sick animals, stress reduction and good nutrition help prevent infectious disease outbreaks and keep cattle healthy and productive. Work closely with your veterinarian to develop and implement science-based herd health programs for cattle disease prevention and control. Learn here more about catttle health tips and guide .