Neospora caninum was organism described as parasite of domestic dog. The tissues cysts seen in neural tissues. The disease can be transmitted by vertical and horizontal. Trans-placental infected pubis: the typical presentation is a flaccid and hind limb paresis Neospora abortion tends to peaks at mid gestation. Serological positive calves will ultimately give birth to calves that are infective and seronegative. Seropositive cow produce less milk than seronegative cows. Neosparn caninum was shown to use cattle as intermediate host and dog as definitive hosts. The most recommendation for prevention is try to prevent fecal contamination of feed and water on the dairy. Trichomonas fetus found in the vagina, uterus, macerated fetus, prepuce, epididymis and vasdeferense. Bovine trichomoniasis is venereal disease manifest in the cow and heifers by infertility, abortion up to 5 ts month after breading pyometra, and fetal mummification. Therefore, some of the common causes of abortion on cattle are discussed in detail in this review. Keywords: abortion, cattle, trichomoniasis, diagnosis, neosporiasis DOI : 10.7176/JBAH/9-21-06 Publication date: November 30 th 2019