Reproductive performance of Bali breed and the Indigenous local breed cows mated by Ongole breed bull applying the artificial insemination technique

The selection and use of cow breeds with high growth rates of the offspring weights produce a correlated response to birth weight and therefore increases the incidence of difficult calving (dystocia) in cows. The artificial insemination (AI) using semen from the prominent Ongole bull is now commonplace in North Sulawesi Province of Indonesia. The risk of selecting Bali breed and other Indigenous local breed cows for artificial insemination technique with semen from heavier Ongole bull remains questionable due to the association with increased birth weight, leading to a higher incidence of dystocia. Calf birth weights of 92 four-year-old cows, accumulated over five years (2020-2025), were used to directly assess the impact of Bali breed and other Indigenous local breeds mated with artificial insemination involving Ongole bull semen on calf weight, and calving ease in Bali breed cows and the Indigenous local breeds. Data were analyzed using a covariance model. The results of the study indicated that Bali breed and other Indigenous local breed cows can be used as the potential animal parental stock in the program for improving and developing Indonesian tropical cattle to increase the live weight of crossbred calves from superior bulls of the Ongole breed without causing more cases of calving difficulties (dystocia). The birth weight of male calves resulted from crossbreeding between Indigenous local breed cattle with Ongole bull was significantly heavier than the birth weight of female calves resulted from crossbreeding between Bali breed cows and Ongole bull applying the artificial insemination techniques. Selection of Bali breed cows and other Indigenous local breeds that have given calf birth greatly supports the crossbreeding program with an artificial insemination (AI) mating system to minimize cases of calving difficulties (dystocia) in the parturition process of the cows.