It’s breeding season, a critical period for many sheep producer operations, and it’s time to ensure that your flock thrives in the coming year. The success of a sheep operation depends on the number of lambs raised, weaned and marketed each year.
Seasonal Timing in Sheep Breeding
Sheep, like many other mammals, are profoundly influenced by the changing seasons. Most sheep will stop cycling when the days start getting longer, typically in January or February, and return to cyclicity when the days start getting shorter, around August or September. This cyclical pattern is intricately tied to the photoperiod, the amount of light and darkness during the day.
In essence, sheep are short-day breeders, which means they prefer to mate when the days are shorter and nights longer.
During the autumn and winter months, ewes enter their 17-day estrous cycles, becoming sexually active. However, from late winter through to autumn, they experience a period of sexual inactivity known as anestrus. While most sheep follow this pattern, certain breeds with a naturally long breeding season (such as Dorset, Polypay, Rambouillet, Targhee, Katahdin and Finnsheep) deviate from the norm. These breeds start cycling sooner and adapt to fall lambing with more success than breeds with shorter breeding seasons, which typically last for four months.
Because my flock is mostly North Country Cheviot, I’ve always put the rams and ewes together near the end of October or early November. That means I’ll be looking for lambs around the first of April.
Managing Body Condition for Breeding Success
One of the key determinants of a successful sheep breeding season is the body condition of your ewes. Animals that are either too thin or too fat may not cycle into estrus and will not be bred. Ideal body condition is typically rated at a 5 or 6 on the Body Condition Score (BCS) scale. It’s essential to assess BCS before the breeding season begins, and it should be maintained throughout the season and at lambing or kidding.
For those that are not in ideal condition, there is a practice known as “flushing.” Flushing involves increasing the amount of feed offered to the animals, typically two to three weeks before the breeding season. This extra nutrition helps them put on weight prior to breeding. Ewes that are already in good condition usually don’t respond to flushing.
Don’t overlook your ram when it comes to body condition. They typically lose weight during the breeding season due to increased physical activity and decreased feed intake, so monitoring their condition is crucial.
Health Management for Breeding Success
In addition to body condition, the overall health of your flock plays a pivotal role in a successful breeding season. Regular health management practices include hoof trimming, vaccination and deworming.
Proper hoof care is vital, especially during a period of increased activity for both ewes and rams. It’s essential to examine their feet for sores, signs of foot rot, infection and overgrowth. Healthy hooves ensure that your sheep can move about comfortably and actively participate in the breeding process.
Vaccination is another critical aspect of health management. Producers should consider vaccinating twice per year, starting at the beginning of the breeding season and again four to six weeks before lambing. If you only vaccinate only once per year, it’s best to do so four to six weeks before lambing to ensure that immunity is passed to the lamb or kid. Additionally the lambs should be vaccinated at 8 weeks old, with a booster at 12 weeks. I use a CD&T vaccine, which protects against overeating disease and tetanus. Definitely talk to your vet about what they recommend for vaccination.
Deworming is another important pre-breeding season task, particularly if you plan to flush your ewes. You should do the deworming before flushing to get optimal health and reproductive success.
Optimizing Breeding Season Duration & Ratios
The breeding season should last for at least 40 to 45 days to allow ewes to complete two estrous or heat cycles, or about 34 days. My research shows that a ratio of one ram for 50 ewes is about right. This ratio helps ensure that each female has the opportunity to mate and conceive, optimizing her overall breeding season.
By paying attention to seasonal timing, managing body condition, and ensuring the health of your animals, you can set the stage for a productive and successful breeding season, ultimately leading to a thriving flock.
Good luck to all who are looking forward to some lambs in the coming months!
