EFFECTS OF PARITY AND BREEDING TYPE ON PERFORMANCE OF RED CHITTAGONG CATTLE

Abstract

The study aimed to explore if parity and breeding type had any effect on performance of the Red Chittagong cattle (RCC). Retrospective records of a total of 20 dairy cows from the 1st to the 2nd parities were collected from the record sheet from January 2020 to June 2022. Results indicated that birth weight of the RCC calf was 7.5% higher (P=0.023) in parity 2 compared with parity1. Accordingly, total milk yield per lactation was 10.2% higher (P=0.004) in parity 2 compared with parity 1. Age at first service was 34.7% higher (P=0.001) in parity 2 compared with parity 1. Accordingly, age at first conception was 38.3% higher (P=0.001) in parity 2 compared with parity 1. The dry period was 22.8% higher (P=0.001) in parity 1 compared with parity 2. Age at first service was 18.3% higher (P=0.014) in natural service (NS) compared with artificial insemination (AI). Age at first conception was 16.5% higher (P=0.023) in NS compared with AI. Post-partum period was 11.9% higher (P=0.008) in AI compared with NS. Days open was 8.9% higher (P=0.018) in AI compared with NS. Calving interval was 2.9% higher (P=0.006) in AI compared with NS. An increased probability of infertility was associated with NS compared with AI. Birth weight of the calf was negatively associated with milk yield of the dam. Unlike birth weight, milk yield was positively related with the live weight of the dam. An increased dry period and post-partum period was positively associated with increased milk yield at the expense of reproductive health. An increased probability of milk fever, mastitis, metritis and infertility was associated with increased milk yield. Days open, calving interval and service per conception were the principal eigenvectors determining performance of the RCC. It was concluded that the RCC performed better in the 2nd parity with AI compared with NS.