Breeding Meat Goats Seasonality & Bigger Litters
Most goats are seasonal breeders, with the length of the breeding season varying between individual goats within breeds and between breeds. The breeds of dairy goats that originated in the Alpine Mountains of central Europe (Saanen, Toggenburg, French Alpine, and Oberhasli) have an average breeding season of about six months in Northern Arkansas and Southern Missouri. Nubians and Boers have longer breeding seasons and have more variations in the length of their breeding seasons. These two breeds were developed by crossing diverse types of goats from several different parts of the world. It has been reported that the farther from the equator a breed of goats originates, the shorter is the length of its average breeding season, and breeds (such as the pigmy) that originate on the equator will breed the year around at any location.
Savanna Meat goats are also reported to be non-seasonal breeders. It has also been reported that breeds of goats which are seasonal breeders in the northern parts of the United States will breed the year around in the southern most parts of Florida and Texas.
The start and end of the breeding season in goats is determined by changes in day length. In seasonally breeding goats the breeding season usually begins 60 days after the longest day (late August) and ends 60 days after the shortest day (late February.) The dates of coarse would be reversed in the southern hemisphere. It is the change of the length of uninterrupted darkness that determines the beginning and end of the breeding season in goats.
We find that mid to late March kidding works best in this area for optimum utilization of pasture for feed. Pastures are at their peak level of nutrition when does are at their peak level of milk production. December and January kids are ideal for the market meat goat shows at the county, district, and state fairs in Arkansas. October and November kids would be best for the Missouri fairs. Goats would have to be breed out of season to get October and November kids. The average gestation period for goats is five months or 152 days.
Managing Meat Goats to Increase the Number of babies Born Per Doe
Research, done in Australia, has shown that running multiple bucks with a herd of does encourages the bucks to rut harder and increases the number of multiple births. Since we have registered Boer goats we can only run one fertile buck with the herd, so we use a vasectomized buck for the second buck. The first vasectomized buck we used was a full blood Boer and he worked fine when he was young but when he got older and we started using a younger herd sire he wouldn’t let the younger buck breed the does. So we recommend using a vasectomized Pygmy buck as the second buck. Since Pygmy goats are not seasonal breeders. Vasectomized Pygmy bucks, that rut during the non-breeding season, can often be used to get other breeds of goats to breed out of season.
Research has shown that feeding does high nutrient diets for at least three weeks prior to placing a buck with them increases litter size (sometimes, but not always.) In studies done in Australia and at Cornell University, feeding to increase litter size worked. In studies done at Langston University it did not work. There is a real need for further research on this.
The process of feeding livestock to increase litter size is called flushing. The term flushing is also used in the embryo transplant industry for the process of removing embryos from a donor animal.
We wean our kids on July first. In late August, if pastures are poor, we start feeding small amounts of grain our does. When the acorns start falling we stop feeding grain because the goats get plenty of nutrients from the acorns and pasture. We put the buck with the does on October 7th or 8th. We are able to average two kids per doe using this system. Two kids per doe are ideal for our management practices.
The summer of 2011 was very hot and dry. I had some health problems, and we were unable to feed the does in August. That year there were no white oak acorns but we had a lot of red oak acorns which start falling later than the white oak acorns (about three weeks before we put the buck with the does.) The does were very thin, but they were gaining weight fast when we put the buck with them. We were expecting to get mostly singles. Out of eighteen does, we got one set of twins. The rest of the does had triplets and quadruplets. We averaged over three kids per doe. When the acorns started falling these goats were thinner than we would ever want our goats to be. The extremely hot, dry weather killed most of the internal parasite eggs and larva in the pastures. Under normal weather conditions for northern Arkansas, goats this thin would have been lost to internal parasites. Goats that are not properly fed are more susceptible to internal parasites. These goats were in good condition by time they started kidding.
In our herd young does kidding for the first will have more singles than older does. We feed our doe kids, that are growing, a higher level of nutrition than our dry, older does. This might be why they have more singles. We need more research on this.
Genetics also influences litter size. Some does will always have singles. In our herd they are culled. We had two does that always had triplets and quadruplets. They were mother and daughter, but most of their daughters had normal litter sizes.
This information is not intended to recommend feeding practices for controlling litter size in meat goats. It is intended to show the need for more research on the effects of feeding on litter size in goats.