It is caused by gram negative bacteria Brucella sp. The major symptoms are

• Fever, anorexia and depression in the animal

• Swollen testes (orchitis) is one the major symptoms and is often due to the inflammation in the seminal vesicles and epididymis

• Inflammation may lead to fibrosis in the testicular tissues

• The disease may spread to the female through semen.

It is viral disease caused by Bovine viral diarrhoea virus from family Flaviviridae. It can affect most of the tissues of the reproductive system. The major symptoms are

• High fever (105-107 °F), loss of appetite, and mouth ulcers

• Blood discharge in diarrhoea

• Discharge from nose and eyes. In some cases, pneumonia may be present.

• Persistently infected calves, calves infected while in the uterus of female within 125 days of pregnancy, may produce semen with acceptable quality but poor fertility

• New born calves infected with BVD may show ataxia, tremors, diarrhoea

IBR is caused by Bovine Herpesvirus and causes acute inflammation of upper respiratory tract. Major symptoms are

• Fever, loss of appetite, depression, coughing

• Nasal discharge, hyperemia of muzzle, pink muzzle

• Redness in conjunctiva and ocular discharge

It is infectious veneral disease of cattle caused by bacteria Campylobacter fetus and is transmitted through semen. It causes abortion and infertility in cows. The semen quality may not be affected. In general, young bulls may get rid off infection within 30 days while the older bulls (more than 3-4 years) may get persistent infection. Bulls are generally asymptomatic while female shows signs like irregular estrous cycle, abortion (early embryonic deaths), repeat breeding etc.

It is caused by flagellated protozoa, Trichomonas foetus. It also does not cause changes in the semen quality. Yooung bulls usually recover and are transient carriers of the disease while the older bulls (more than 3 years) usually act as carriers of the disease and show no clinical signs. The cows show signs like vaginitis, endometritis, pyometra, reduced pregnancy rate, abortion (early embryonic death) and pyometra etc.

The leptospirosis is a bacterial disease caused by Leptospira sp. It is a zoonotic disease and may be transmitted by animals or through environment. Symptoms are usually dependent upon the age of the animal, immunity of the herd, and virulence of the infectious agent. Major symptoms in calves not adapted to the Leptospira sp. are high fever, anemia, blood in urine, jaundice and death within 3-5 days while older animals may get mild fever and lethargic and their symptoms may get unnoticed. The adapted animals shed bacteria in urine and their kidneys are infected and hardjo-bovis causes reproductive infections. Symptoms may include delayed breeding, early embryonic death, infertility, abortions, weak calves etc. in the herd.

• Before introducing any bull in the breeding, it should be certified by veterinarian after screening for different diseases.

• Quarantine measure should be followed for the newly purchased bull.

• The bulls should be vaccinated for the diseases.

• Any case of abortion or reduced fertility in the herd should be reported to the veterinarian.

• A record of the bulls bred with cows and vice versa should be maintained.

• Farmers should avoid using bulls from other farmers or semen straws from non-certified labs.

• Farmers should also avoid using their bulls outside their farm. If they use a record should be maintained for the female animal that have been bred with the bull and vice versa.

• The semen straws should be purchased from the certified semen stations and veterinary hospitals only.

• Farmers should be made aware about the quarantine and vaccination of animals.

• Farmers should be trained and encouraged to maintain breeding record animal in such a way that the animals involved in breeding can be traced easily.

• Whenever a bull is introduced in the herd by farmers, the bull should be screened for the infectious diseases from a certified laboratory.

• The case of abortion or reduced fertility in the area should be screened for the infectious diseases of reproductive system

• Trace out the animals that have come in contact with the animal, or its semen, infected with the infectious agent of reproductive diseases. Screen all those animals for the causative agent using suitable tests.

• All the infected and suspected animals should not be used for breeding before their treatment and vaccination.

• Depending upon the infectious agent identified, the higher authorities may be informed and a suitable plan may be devised for the area.

• Make the farmers aware about any such infectious agent and its consequences so that co-operation from the farmers and higher authorities can be obtained and the infectious agent can be countered successfully.