Enhanced reproduction and its economic implications.

Reproductive performance affects profit of dairy herds because it directly affects milk produced per cow per day, number of replacements produced, and rates of voluntary and involuntary culling. High producing cows will reproduce at a satisfactory rate if they are managed properly. There appears to be direct relationship between herd management and reproductive performance. Thus, reproductive performance and profit respond positively to improvements of rates of detection of estrus, improvements of rates of conception, and improvements of management of the periparturient cow. Pharmacological procedures are now available for controlling time of estrus and insemination in groups of cattle. It is feasible to limit the breeding period in a herd to 1 wk of each 3-wk interval. Primary benefits of controlled breeding are convenience and efficient use of labor for detection of estrus and insemination. Biotechnical procedures such as embryo transfer and insertion of specific genes may enhance rates of genetic improvement for important economic traits.