A significant aspect of proper heifer rearing is good reproductive management, shared Ricardo Chebel at the 2010 Dairy Cattle Reproduction Council (DCRC) Annual Meeting in St. Paul, Minn. Without a focus on reproduction in heifers, a longer interval to onset of productive life occurs and results in economic losses. During the presentation Chebel reviewed basic principles of reproductive physiology, expected reproductive efficiency, and explored some of the new strategies available for reproductive management of dairy heifers.
Despite the fact that several protocols have been developed and tested for reproductive management of heifers, 57.1 percent of herds inseminate heifers for the first time based on spontaneous signs of estrus. Several considerations have to be made before choosing one protocol over another, principally cost of protocols and return over investment.
The cost benefit of implementing synchronization protocols in dairy heifers goes beyond reducing the interval from puberty to the start of the first lactation. Assuming that the ideal age at calving would be 23 months, as long as body weight is appropriate, we can then calculate the value of synchronization protocols for heifers based on number of days saved from the start of the synchronization protocol to first calving, and the costs associated with the synchronization protocols.
Dairy heifers that have reached puberty will demonstrate strong signs of estrus, which should result in high estrous detection rates in herds with appropriate facilities and personnel for daily estrous detection. Synchronization of heifers will reduce the interval to first breeding, which is likely to overcome the additional cost associated with treatment. Although significant progress has been made in regards to fixed-time A.I. protocols for heifers, there are significant costs associated with the implementation of such protocols. However, synchronization protocols remain economically viable solutions in the heifer pen.
Source: Dairy Cattle Reproduction Council