Diseases

Infection Bovine Rhinotracheitis/ Infectious pustular vulvovaginitis (IBR, Red nose)

Pathogen: Bovine herpes virus type-1

Nature of the disease: Can cause a variety of syndromes according to which tissues it affects in bovines including the respiratory form „IBR“, infectious pustular vulvovaginitis „IPV“, infectious pustular balanoposthitis „IPB“, ocular, abortion, encephalitis, and fatal systemic infection in new borne calves

Transmission: Sources of the virus are the infected droplets from nasal secretions, semen, and fetal fluid tissues of infected or those recovered carrier’s animals. Aerosol infection is considered to be the main route of infection for the respiratory form of IBR, while venereal transmissions are the method of spread of the genital form.

Influence on reproduction: Depending on when the infection occurs during gestation, it can result in early embryonic death and infertility, or IBR infection can result in late­term abortion (five to nine months of gestation). Cows aborting due to an IBR infection may experience temporary infertility from vaginitis after the abortion.

 

Bovine viral diarrhea (BVD)

Pathogen: Pestivirus among the Togaviridae

Nature of the disease: Has different syndromes depending primarily on the virus strain, immune status and age of the infected cattle or the foetus, as well as stressors interaction. Its clinical signs range from subclinical to severe fatal infections, which may include fever, diarrhea, ulceration and erosion of the alimentary mucosa, salivation, respiratory signs, leucopenia, abortion, and congenital anomalies.

Transmission: Horizontal transmissions occur through direct contact with diseased animal secretions and can occur indirectly through contaminated feed, equipment and through blood-feeding insects. Vertical transmission is common because the virus readily crosses the placenta and plays an important role in BVD-MD epidemiology and pathogenesis. BVDV usually brought onto farms by persistently infected cattle „carriers“ that can act as a continuing source of infection within the herd, whereas acutely infected cattle shed the virus for short period (14-21day).

Influence on reproduction: reproductive problems (irregular heats, abortions, premature births, birth of weak or stunted calves

 

Brucellosis (Bang disease)

Pathogen: Brucella abortus

Nature of the disease: Brucellosis is the contagious disease caused by the genus Brucella, in which it generally cause reproductive failure; that is, abortion or birth of unthrifty newborn in the female, and orchitis and epididymitis with frequent sterility in the male in a wide range of animal species and can affect man.

Transmission: Brucellae are present in the placenta, fetal fluids, fetus, vaginal discharges, milk, semen and urine. The major sources of infection are the contents of the pregnant uterus, the fetus and the fetal membranes.

Influence on reproduction: abortion, orchitis, epidimitis, sterlity in the male

 

Vibriosis (Campylobacter fetus)

Pathogen: Campylobacter fetus

Nature of the disease: Campylobacter which can infect the reproductive tract of both male and female cattle. It typically causes infertility during the breeding season due to loss of early pregnancies

Transmission: Campylobacter typically survives in the reproductive tract of an infected bull. The infected bull will pass the bacteria to cows via sexual contact.

Influence on reproduction: high percentage of cows in the herd returning to estrus (heat), decreased pregnancy rates and an extended breeding season. Infrequently, cows may abort between four and eight months

 

Trichomoniasis (Trich)

Pathogen: protozoa Tritrichomonas fetus

Nature of the disease: This disease causes very few outward signs of illness. Therefore, it can often be present in a herd for a considerable time before it is suspected and diagnosed.

Transmission: The bull acts as the main source of transmission for the herd. In bulls, the organism lives on the tissue lining of the penis and preputial sheath.

Influence on reproduction: Infected cows will experience infertility and early embryonic death, causing the cow to return to heat and subsequently leading to poor pregnancy rates and extending the breeding season Infected cows may display a thick, yellowish vaginal discharge while infected, but in many cases no outward signs may be apparent in infected cows

 

Leptospirosis

Pathogen: Leptospira sp.

Leptospirosis is a disease that can affect several species including cattle, sheep, pigs, dogs, horses, wildlife and man. This disease is caused by bacteria that are well suited for wet, moist environments.

Transmission: Cattle can be exposed from contaminated stock ponds, wildlife, rodents or infected domestic animals. Transmission can occur when the bacteria penetrate a conjunctiva, genital tract) or enter open wound. Once an animal is infected, the organism circulates throughout the body and localizes in the kidneys, mammary glands and genital tract. When the urogenital tract becomes infected, the bacteria can be shed in urine, uterine discharge, semen and aborted fetuses/placentas. This shedding allows other herd mates to become exposed and infected.

Influence on reproduction: Leptospirosis may lead to many reproductive problems such as infertility, early embryonic death, lateterm abortions, weak newborn calves and lowgrade uterine infections.