Grass Quality Plays Key Role in Beef Cattle Breeding

By Scout Nelson

As spring arrives, cattle producers look forward to moving cattle to pasture and starting a new breeding season. However, this time also brings challenges in managing nutrition and reproduction.

Rebreeding success starts with proper care after calving. According to experts, a cow must begin cycling again and become pregnant within 80 to 85 days after calving to stay on track for yearly calving. At the same time, she is also feeding her newborn calf.

The first 90 days after calving are the most demanding. During this period, cows need more nutrients because milk production takes priority over reproduction. A cow that calved two months ago may need up to 1.5 times more protein and energy than she did before calving. Without proper nutrition, she may lose body condition, lowering her chances of getting pregnant again.

Research shows cows that enter breeding season in thin condition, with a body condition score of 4, have lower pregnancy rates. These cows may only reach a 58% pregnancy rate, even with more time to breed. However, cows in moderate condition, with a score of 5, show an 85% success rate.

Grass quality plays a big role in nutrition. In late spring, grasses like Kentucky bluegrass and smooth brome offer high protein and energy levels. But as summer continues, the quality of these cool-season grasses drops. Warm-season grasses can help make up for this decline in late summer.

By fall, grass protein and energy levels fall below the needs of lactating cows. Knowing which grass species are growing in your pasture can help plan better grazing and meet the cows’ nutritional needs.

Photo Credit: gettyimages-ahavelaar