Effects of Supplemental Methionine Or Choline on Health and Performance of High-Risk Receiving Beef Heifers.

The main focus of the first study is the impact of vitamin A supplementation during early fetal to neonatal stages on growth and muscle development in Korean native calves. Results showed that vitamin A supplementation increased serum vitamin A and glucose levels, improved birth and weaning body weights, and upregulated genes related to muscle and pre-adipocyte development. The second study evaluated supplemental methionine or choline on health and growth in high-risk receiving beef heifers, finding no significant effects on growth performance, feed intake, or respiratory morbidity. The third study investigated calcium magnesium carbonate (CMC) and tylosin phosphate (TYL) supplementation in yearling beef steers, observing that CMC reduced dry matter intake and altered rumination behavior, while TYL slightly increased intake; however, neither supplement significantly affected growth efficiency or carcass characteristics.