Agricultural Science: Beef Cattle Breeding Management

When creating a management plan for breeding beef cattle, one must look at both the genetics and breeding of the bulls and heifers equally. It is just as important to keep track of the mother’s data as the father’s. First data points should, of course, be the genetics of each. You do not wish to breed too closely within a group; fathers bred to daughters is not desirable for a variety of reasons. Once you have a clear line as to who is related to whom you can move on to their EPD’s (Expected Progeny Differences).



A cattle’s EPD provides “estimates of the genetic value of an animal as a parent” (Greiner, 2009).  EPDs predict the genetic outcome if two animals of the same breed are bred together. They calculate the birth, growth, maternal, and carcass traits of the potential offspring. They do not work if breeds are crossed unless much adjustments are made. These EPD rates assist in making decisions on which bulls and heifers to breed together.

When looking at traits to enter into the EPD calculations or when gauging by notes, producers should look for the following traits in their heifers. Heifers should be fertile at a young age. They should have short post-partum intervals and easy calving. They should handle stress well while maintaining moderate milk volumes and be an efficient grazer who can maintain their body condition. They should also be docile and not have any hoof or leg problems (Treffer, 2016).

“When evaluating a bull’s breeding value against his cost, it is important to take into account not only the bull’s purchase price, but the annual feed and care cost that will be associated with using him to sire calves” (Berger, 2016). Other costs taken into account should be the cost per pound of calf produced, the credit of the bull’s salvage value (culling value), and the potential for injury during natural breeding. When researching and calculating the cost of natural service by ownership or rental of bulls, one should also look into artificial insemination (A.I.) costs.

When looking into A.I., there are a few options to consider: synchronizing estrus, timed A.I. at GnRH injection, or delayed insemination of non-estrus expressing beef heifers. Synchronized estrus in the herd can shorten the calving season, produce more uniform calf weights, and allow the opportunity for A.I. if desired (Johnston & Funston, 2015). Even if you use a synchronized estrus program and follow all the rules for A.I. on injections, semen protocols, etc., one can still use bulls to breed those heifers that do not conceive through the A.I. the ratio should be about 1:10 (1 bull to 10 cows). Of course, the cows will not come back into heat on the same day, so you can stagger the insemination rates and dates. This means that the 238 day gestation may be a bit earlier for easy-births and longer for harder-births (Johnston & Funston, 2015). Comparisons in estrus synchronization programs that includes a timed A.I. program that is injected at 12 hours after initial Gonadotropin Releasing Hormone (GnRH) injection with one where the A.I. is withheld for 19 hours have shown that there is no difference in insemination rates within herds (Funston, Nielson, Kelly, & Meyer, 2016). This should be taken into account when planning any A.I. programs for herd management.

Lastly, one must look at the facility the cows will be birthing in. Depending on the pasture the herd, or at least a portion of the herd, may need to be confined through breeding season. If this is the case the heifers should have their feed increased the percentage of “energy dense feed such as distillers grains…or silage” or by increasing the amount of normal feed (Funston & Jenkins, Breeding Cows in Confinement, 2013). Herd space (bunk space) will also need to be factored with a minimum of two feet per cow, and additional eighteen inches for each calf, and two feet for each bull if they are co-housed. Feed rations will need to be increased as well, potentially up to eighteen pounds of TDN (total digestible nutrients) for each bull (Funston & Jenkins, Breeding Cows in Confinement, 2013).

If producers synchronize their heifers and use a timed service they can get more calves born earlier in the calving season, which can lead, depending on the timing, on up to two more calves than later calving heifers over a nine-year span of time. These early season calves typically have better marbling and grading and greater weaning and carcass weights, which in turn create better final credits (Funston & Jenkins, Breeding Cows in Confinement, 2013).  In combination with proper genetic tests, EPD rates, an insemination plan, and facility development, producers can keep their herds healthy and profitable for years to come.

References

Berger, A. (2016, February). How Valuabull? Retrieved February 3, 2017, from University of Nebraska-Lincoln Institute of Agriculture and Natural Resources: http://beef.unl.edu/how-valuabull

Funston, R., & Jenkins, K. (2013, May). Breeding Cows in Confinement. Retrieved from University of Nebraska-Lincoln Institute of Agriculture and Natural Resources: http://beef.unl.edu/cattleproduction/breedingcowsinconfinement

Funston, R., Nielson, H., Kelly, D., & Meyer, T. L. (2016, May). Comparison of Timed AI at GnRH Injection and Delayed Insemination of Non-estrus Expressing Beef Heifers. Retrieved January 30, 2017, from University of Nebraska-Lincoln Institute of Agriculture and Natural Resources: http://beef.unl.edu/comparison-study-on-non-estrus-expressing-beef-heifers

Greiner, S. P. (2009, May 1). Understanding Expected Progeny Differences (EPDs). Retrieved February 3, 2017, from Virginia Cooperative Extension: https://pubs.ext.vt.edu/400/400-804/400-804.html

Johnston, B., & Funston, R. (2015, May). Estrus Synchronization Considerations in Beef Herds. Retrieved February 2, 2017, from University of Nebraska-Lincoln Institute of Agriculture and Natural Resources: http://beef.unl.edu/estrus-synchronization-considerations-beef-herds

Treffer, B. (2016, March). Selecting Replacement Heifers. Retrieved January 31, 2017, from University of Nebraska-Lincoln Institute of Agriculture and Natural Resources: http://beef.unl.edu/selecting-replacement-heifers