Sheep

Better Breeding Season Starts with Sheep Body Condition Score

Wellness : Health

Clay Elliott, Ph.D.

Companion Animal Nutritionist, Technical Solutions

It's easy to overlook sheep body condition score (BCS) during the summer months. Your ewes have what they need to be self-sufficient until it's time to turn the bucks out again: fresh air, plenty of pasture, water and likely access to a free-choice sheep mineral supplement.

But sheep breeding season arrives sooner than you think. Make sure to give ewes more than a passing glance during the summer months to make sure they are in good condition for successful pregnancies.

Evaluate sheep body condition scores

Use a BCS chart to assess your flock's condition. Depending on flock size, it may not be practical to check the condition of all ewes. In that case, score approximately 10-20% of ewes to get an estimate of the flock’s condition.
 
At 45 to 60 days before the beginning of the sheep breeding season, ewe BCS should be 2.5 to 3.0 for optimal breeding and conception results. Maintaining body condition scores, or improving those for thin ewes, during the first 90 days of pregnancy helps promote embryo survival.
 
Too-thin ewes (1.5 BCS or below) may not only be weaker and more susceptible to disease, but they also typically take longer to conceive during breeding season. That’s because under-conditioned ewes may skip heat cycles until they get back to ideal weight.
 
Over-conditioned ewes (4.5 BCS or above) are also not reproductively or financially efficient. These females tend to take longer to breed, leading to delayed lambing and reduced lamb gain.

Hit the body condition score target

To hit a target BCS of 2.5 to 3.0, consider adding a supplemental fat and protein source. Supplemental fat can help maintain condition and is especially important if ewes trend toward the thin side. Fat has 2.5 times more energy than a carbohydrate like corn, making it the most efficient way to add energy into a diet.
 
Ideally, supplements should be offered year-round to maintain BCS through every season. It’s especially important to provide supplemental fat when forage nutrient values are declining through late summer, fall and winter.

Lambs win too

Supplementation is critical as ewes enter the third trimester, when 75% of fetal growth occurs. If the ewe can't get enough energy into her system during this timeframe, she can lose condition since the fetus is taking many of the nutrients.
 
As a ewe gets later into gestation, her rumen competes for space with the growing lambs. An energy-dense supplement provides the nutrition the ewe needs in a smaller package, allowing her plenty of space for both the rumen and lambs.
 
Once lambs are born, maternal nutrition remains important. A higher level of dietary fat can influence milk fat content. In turn, higher milk fat helps lambs get a better start with extra energy for rapid and efficient lamb growth.
 
Start today by zeroing in on ewe BCS to ensure your flock is ready for the breeding season. Download the BCS chart as a tool to monitor flock performance.