Factors affecting cow efficiency in a Bonsmara herd at Koopmansfontein research station

Abstract

This study investigated the factors affecting cow efficiency in a Bonsmara herd at the Koopmansfontein Research Station. Twenty-four pure-bred two-year-old Bonsmara heifers were stratified according to their age and divided into two experimental groups. All heifers used for the study were in good body condition, with an average body condition score (BCS) of 3. The control group only received summer lick (October to March) and winter lick (April to September), while the treatment group received a summer lick during the summer months, but production lick instead of a winter lick during the winter months. The recommended intake of winter lick for cattle is 400–650 g per day, and the recommended intake of summer lick is 100 g (minimum) – 200 g (maximum) per day. A ratio of 2:1, which is two bags of winter lick and one bag of yellow maize, was used as the production lick. There was a significant difference (P = 0.034) in pelvic measurements between the pelvic area of the two heifer groups. Supplementing heifers with production lick resulted in a larger pelvic area (214.9 ± 21.63 cm²) and higher calving rate, with heavier calves at birth. The findings of the study demonstrated that heifers supplemented with production lick weighed significantly more (426.3 ± 39.5 kg), than those supplemented with winter lick (361.8 ± 41.6 kg) in 2020, and the production lick group had more calves which is 11(91.67%) calves in their first calving season. The PL group had a higher calving percentage (P < 0.05) than the WL group. Understanding cow efficiency factors allows producers to implement strategies that improve cow efficiency, thereby increasing productivity and sustainability within the livestock industry. Nutritional supplementation played a vital role in the reproductive performance and achieving appropriate target weights prior to first breeding which had a positive effect on re-breeding after the first calf. Proper supplementation can also positively influence calf weights during weaning, aligning with previous research that heavier calves at birth have higher weaning weights and improved cow efficiency.