The Importance of Flushing in Livestock
In rearing livestock, some practices are carried out to ensure optimal productivity. One of them is ‘flushing’ which is the practice of increasing nutrient intake and body condition before and during breeding.
When the female animals such as Cows, Ewes, Does, or Sows are deficient in nutrients, and their body condition score (BCS) is low, their productivity rate becomes low. Hence, we carry out flushing to increase the quality of grains and forage which the females are fed during their breeding phase.
This is to improve their body condition, ovulation rate, and to increase the number of young ones they give birth to.
In an experiment conducted in the Department of Animal Science, University of Nebraska–Lincoln, the students left cows after calving to be thin and slightly underfed until 14 days before the start of the breeding season. Then the cows were fed a high energy diet (consisting of 8.8 to 13.2 pounds of ground corn per head per day and corn silage free choice) from about 30 days into the breeding season. These cows responded with enhanced reproductive performance.
Their response to flushing was influenced by:
- Age of the animal (mature ones show a greater response than yearlings)
- Breed (prolific breeds are least responsive)
- Body condition (thin animals respond more than those in above- average condition)
- Stage of the breeding season (greatest response is seen early and late in the breeding season).
Special feeding usually begins around 2 weeks before breeding and continues at least 2 to 4 weeks into the breeding season. The reason for continuing on that plane of nutrition after breeding is to decrease embryonic death loss. The extra feed ensures the fertilized eggs have a much better chance of attaching to the uterus wall, rather than being reabsorbed due to lack of energy from the mother.
In another experiment, the following table indicates the required length of time necessary to bring ewes in below-average condition up to the ideal breeding condition.
|Ewe body score||Flushing period (weeks)|
Farmers do not continue flushing too long after the breeding season, because an extended period of high feeding is unnecessarily costly, and provides no improvements in animal performance and productivity over time. You only perform flushing before and during the breeding season to increase productivity.