RESUMO
Bovine Venereal Comylobacteriosis is still a serious problem of dairy herds in Tehran province. Most of these herds use natural service to breed cows. However, artificial insemination is also used in some herds. In a herd of 184 Holstein cows, located in southern part of Tehran, compylobacter fetujs var. venereal is was isolated from an aborted fetus and classified in veterinary organization central laboratory. Further investigations revealed that eight bulls had been used for natural service for several years in the herd. Manipulating data from reproductive records of the herd showed that nineteen pregnant cows [10.3%], being at different stages of pregnancy, experienced abortion and/or stillbirth during the period of one year. Mean days open was estimated to be 141 days, indicating a severe infertility in the herd. A high percentage of repeat breeders [37.5%] were observed. Cows had also a high incidence of endometritis and cystic ovarian disease [25.7% and 11.6% respectively]. The reproductive status of the herd was improved rapidly following the removal of bulls from the herd and starting A.I. Thirty four problem cows suffering from reproductive disorders such as repeat breeding, endometritis and cystic ovaries, responded promptly to appropriate treatments and conceived either to the first or the second A.I. Abortions were also stopped following the establishment of artificial insemination in the herd