Livestock producers whose herds have poor reproductive success earn less and have higher production costs per head than those whose herds reproduce successfully, says Dr. David Fernandez, Cooperative Extension Program livestock specialist at the University of Arkansas at Pine Bluff.
In fact, reproductive failure is the most costly problem facing livestock producers. Dairy producers, cow or goat, with longer dry periods have higher feed costs because of increased periods of feeding without production in return.
“One of the main reasons for poor reproductive performance is poor nutrition early in the year,” says Dr. Fernandez. Puberty is one reproduction milestone that responds to management, and the most important management consideration is good nutrition.
Animals that are well fed reach puberty sooner and become pregnant sooner than animals that are poorly nourished. Females that reach puberty earlier are more likely to wean heavier offspring, remain in the herd and generate more income over their lifetimes than females that reach puberty later, says Dr. Fernandez. Heifers should reach puberty by the time they are 12 months old. In general, sheep and goats reach puberty between 4 and 6 months of age.
Females should not be bred until they reach 60 to 70 percent of their mature weight to avoid problems giving birth. Use young males sparingly since they have not finished growing. Males often lose weight during breeding season, and young males could become infertile if they are overused.
Well-fed females become pregnant more easily, and in the case of sheep and goats, are more likely to produce twins. Females that give birth in good body condition are less likely to have trouble with pregnancy toxemia and rebreeding, says Dr. Fernandez. They typically produce more milk and give birth to healthier, faster-growing offspring. Your county Extension agent can help you balance a ration to meet the needs of your animals to insure good reproduction, adds Dr. Fernandez.
Difficult birth, called dystocia, is one of the leading causes of infant mortality in livestock. Young animals that have undergone a difficult birth have trouble standing and nursing. They are often exhausted by their birth and fail to thrive. Mortality from dystocia is commonly seen in the first 48 hours. Dystocia also increases the time required for rebreeding. This is a problem in cattle as cows are expected to rebreed within 85 days of calving to maintain a one-year calving interval, says Dr. Fernandez.
Ranchers should be prepared to assist a difficult birth beginning one hour after seeing the feet or fetal membranes. Be prepared to help immediately in cases of incorrect fetal presentation, such as the fetus emerging backwards or with a leg tucked. If unable to deliver the offspring, Dr. Fernandez advises calling a veterinarian rather than resorting to extreme measures like using a come-along.
Sheep and goats are seasonal breeders which can be a disadvantage when trying to produce lambs or kids for specific holiday markets. The breeding season for both sheep and goats is when days are short, fall and winter. As the days grow longer and throughout the summer, reproductive activity slows or halts.
However, seasonality is not absolute, says Dr. Fernandez. Some breeds, such as Savanna and Myotonic goats, and Dorset, Rambouillet and hair breeds of sheep are less responsive to seasonal patterns. They will often breed throughout the year. There can also be quite a bit of variability in response to season among individuals within a breed.