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Virginia Cooperative Extension - Knowledge for the CommonWealth

Genetic change may be headed in a new direction

Dairy Pipeline: October 2003

Bennet Cassell
Extension, Dairy Scientist
Genetics and Management
(540) 231-4762

One of the most enduring "best management practices" that we advocate to dairy producers is to breed your cows to top AI bulls. AI bulls get better every year; their daughters give more milk and have better type. Plus, you don't have to feed them or live with their destructive and dangerous attitudes. The technology called AI has been around since the late 1930's, and yet many dairy cows and heifers are bred to natural service bulls. AI may be harder to sell today than it was 15-20 years ago because higher milk yields have suppressed estrus behavior, making cows hard to catch in heat. Saying that AI sired cows give more milk doesn't persuade many dairy farmers to use AI any more. They have to use better bulls just to keep pace with their industry, and see little benefit to their businesses for the effort. I sense a change in the wind, however, and would encourage producers to give this idea some thought. We have to tools for farmers to select for more fertile cows, cows that give birth more easily, and for cows that live longer. PTA's for these traits are recent developments and give producers a reason to use AI that didn't exist ten years ago. The benefits of more fertile cows and cows that live longer tend to stay on the farm, as they reduce costs of production, and increase profit margins. Higher milk yield on the other hand, is an income enhancer that may or may not increase margins. Consumers, or dairy food processors, like that extra yield because it creates a buyer's market. Consumers have been the real beneficiaries of better genetics for milk production in this country. The beneficiary of genetic change in fertility and survival of dairy cows is more likely to be the farmer, as production costs go down, allowing the producer to keep more of the milk check. Cows can be bred to be more fertile, and to live longer, and to be more productive, too, by using the Net Merit index published by USDA. Net Merit is a truly balanced breeding program that improves the profitability of the cow to the dairy producer, rather than just keeping milk cheap in the grocery store. I don't want to give the impression that consumers don't matter. The dairy business needs happy customers. I'd just like for dairy farmers to be able to keep more of the benefits from their genetic improvement program. It would make AI easier to sell as a best management practice!

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