by Jessy Shanks
Extension Specialist, Small Ruminant and Youth Programs
University of Tennessee, Knoxville
Sheep and goat producers are constantly searching for ways to improve reproductive efficiency in their flocks and herds. Having more offspring is advantageous to producers and helps them to be more profitable. As we all know, sheep and goats are seasonally polyestrous. This means they experience multiple estrous cycles during a certain season of the year. This means each breeding season is critical to the success of a small ruminant operation. Typically sheep and goats will cycle when daylight decreases, but there are some breeds that are the exception to the rule (out of season breeding). One tried and true method of getting females to cycle earlier in the breeding season, thus lambing/kidding earlier as well, is to utilize a teaser male in the breeding program. This article will discuss the advantages and disadvantages of using teaser males, and will hopefully help producers see if this management tool is right for their operation.
A teaser ram or buck is a male that has been vasectomized. This means that the vas deferens on the male have been cut and tied off to prevent sperm transport into the urethra from the testicles. This prevents sperm from gaining entrance into the female’s reproductive tract, thus preventing pregnancy. The male acts, smells, and even looks like a fertile ram or buck. The only difference is that he is essentially “shooting blanks” when he mounts and breeds a female. The presence of a teaser male does a few things to your flock or herd. If the male is novel or new to the group that he is being introduced to his presence can stimulate females to begin cycling. This is known as the “ram effect” and is quite useful and well documented. The only difference with a teaser is that he cannot actually breed the females because sperm cannot make it into the urethra for transport. Teasers are used to get females cycling earlier in the breeding season, and they can also be used to detect heat when used with females who are being synchronized for an artificial insemination (AI) program. As a producer you might ask yourself why would this be beneficial? The teaser ram or buck can do a lot of the heavy lifting for your breeding male by stimulating ewes and does to come into heat. This saves some effort for your breeding male. Once the females are cycling then you can introduce your actual breeding male and he can be the one to breed them and produce offspring. In an AI program the teaser helps you see which females are in heat and helps you make breeding decisions for AI day (fresh vs. frozen semen, timing, etc.). While this is not required for an AI program to be successful a teaser does help you make informed decisions on AI day.
There are some downsides to using teasers that you may want to consider before jumping in. The actual surgery that produces a teaser male does require a veterinarian and it will take the male some time to heal from this procedure. You may also want to perform a quick semen check to ensure that the male is actually sterile. So while we are thinking about using teasers now in July, it is probably too late to actually have one made and start using him. Although buying a teaser from another producer could be an option. Maiden ewes have not been as consistent in their response to teaser rams for reasons that are unknown at this time, and this could be true for doelings as well. If you already have a ram or buck near your females (fence-line or next to each other in a barn for example) then a teaser might not be as beneficial to your operation. Selecting a teaser male can be tricky but here are a few tips to get you started. First you want to make sure the ram or buck is healthy, has good teeth, eyes and hooves, and has high libido. Sheep breeds that make good teasers include hair sheep breeds, Suffolk, Dorset and Finn sheep. Goat breeds that make good teasers include Kiko and Boer crosses. This male is going to act just like an intact buck/ram so be sure to treat him as such. Once you have obtained a teaser male you can introduce him to your flock/herd about 2-4 weeks prior to your breeding start date. You will have to experiment and see what works with your personal flock/herd.
The goal in using a teaser ram/buck is to tighten up your window of breeding and therefore your lambing/kidding time period. Not every producer will find this practice to be beneficial, but do your research, ask questions of your fellow producers and think about how a teaser ram might benefit your breeding program.
Jessy Shanks is the Small Ruminant and Youth Programs Specialist at the University of Tennessee, Knoxville. Jessy raises Southdown and Dorper sheep with her husband
and daughter just below Knoxville. Her background is in reproductive physiology and she enjoys teaching producers and youth about small ruminants in any way possible.
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