Reproduction & Genetics

Profitability in a cow/calf operation is directly linked to reproduction.

Without reproduction, other management focuses and strategies mean very little. Likewise reproduction is a sensitive mechanism in animals and can be influenced by numerous factors. Understanding the basics needed to achieve herd reproductive efficiency goals is important to building a foundation for a successful cattle enterprise.

What does reproductive efficiency mean?

Reproductive efficiency is calculated by taking the number of calves weaned divided by the number of cows exposed to a bull or artificially inseminated, multiplied by 100. (# of Calves weaned/# of cows exposed to bull or AI) x 100

In practice, an efficient cow will calve live calves at approximately the same time every year. This makes the window for rebreeding small, between 78-86 days. This is not a simple task. Several factors can contribute to the ability for a cow to breed, such as body condition score and plane of nutrition. Overly thin cows and cows who are losing weight at the time of breeding generally do not breed or do not retain pregnancy.

Environment can also impact reproductive success. Most Illinois producers calve in early spring, which means breeding season is in the heat of the summer. Heat stress can contribute to low reproductive efficiency.


General health is also a major factor in reproductive success.

Testing bulls annually to ensure reproductive effectiveness is a must. Monitoring disease pressure within the herd and production environment is important.  Develop a relationship with your local veterinarian. They will be your best resource for preventing, diagnosing, and treating disease.

What about heifers? Replacement heifers are the future of the herd so heifer selection and development should be high priority. Conditioning heifers to your environment will help them develop into quality cows. The general rule of thumb is for heifers to reach 65% of their final body weight before breeding.

Select cattle genetics that fit your management level and production environment.

Many tools are available to aid in selection. While functionality traits cannot be sacrificed, it is important to select genetics that provide traits that fit your market. Utilizing EPD’s (Expected Progeny Differences) can provide an analytic component to help improve your genetics. Develop a relationship with a seedstock provider and be sure to demand cattle that fit your market and excel in the traits you deem important to producing cattle that fit that market.

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