Birth weight in calves is influenced by several factors, including breed, genetics of the sire and dam, length of gestation, age and size of the dam, sex of the calf, environmental factors, and nutrition and health of the dam. Gestation length is heritable, with low birthweight cattle having shorter gestation lengths and high birthweight cattle having longer gestation lengths. Nutrition and weather can also impact birth weight, with calves born in cold seasons tending to have higher birth weights.
The effects of gestation length are important to consider when selecting a bull for breeding. Unexpected factors can influence birth weight, such as genetics of the cattle, maternal effects, and environmental conditions. Nutrition and weather can also play a role, with birth weight being lower in hot seasons and higher in cold seasons. It is important to maintain a balanced diet for pregnant cows to prevent calving problems.
A study found that warmer temperatures during the winter resulted in lower average birth weights in calves, leading to a decrease in calving difficulty. Environmental effects, such as altered blood flow due to temperature changes, can impact birth weight. It is essential to monitor the diet of pregnant cows to ensure proper mineral balance and prevent calving problems related to dietary deficiencies.
