We have developed synchronization strategies that partially solve this problem. Enhancing the percentage of cows that respond to the first GnRH of Ovsynch allows for more cows with accessory CL, greater concentrations of progesterone at time of induced luteolysis (PGF of Ovsynch), and a greater chance for pregnancy.
Rolling Acres Farm, Allegan, MI
Merle Coffey, owner of Rolling Acres Farm, Allegan, Mich., utilizes G6G (see Calendar on page 23, and Figure 3) to increase the reproductive performance of his 800-cow herd. Only cows ready for 1st AI receive the G6G program.
Average days to first service for his herd is now 100 days. After first AI, if cows are detected in estrus, they are inseminated using the AM/PM rule.
If cows reach pregnancy diagnosis (Biopryn at 32 d after AI) and are diagnosed as not pregnant, they are re-synchronized with Ovsynch. Monthly conception rates are displayed in Figures 4 and 5). click image to zoom
These Producers Get Cows Pregnant
Congratulations to Henk Knevelbaard of Fremont, Mich., for being awarded the 2010 Dairy Cattle Reproductive Conference Platinum Level Award.
Henk and his crew (pictured) milk 1,100 cows most of which are Holstein, although, a portion of the herd is being crossed to Swedish Red and Montbeliard sires.
Henk utilizes both estrus detection and timed-AI to achieve top reproductive performance. Approximately 75 percent of cows that are eligible for AI are inseminated following a detected estrus and about 25 % are timed-inseminated following a Presynch-14/Ovsynch program.
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Source: Richard Pursley and Joao Paulo Martins, Michigan State University Department of Animal Science