Ewes that produce a lamb at a year of age should have a higher lifetime production than a ewe that lambs for the first time at two years of age. However, these young ewes are not only producing a lamb, they are also still growing. So, producers should manage these ewe lambs differently than mature ewes.
When selecting ewe lambs to breed, keep in mind that you will have better success if you start by selecting lambs that were born early in the season and from productive ewes. Lambs that were born earlier in the lambing season are more likely to be further along in their maturity and are thus more likely to conceive. As with any selection process, start with looking at performance records and then go to the barn to assess muscling and structural soundness. Ask yourself "Does this ewe lamb meet the criteria that I value in a brood ewe?" If she doesn't, then send her to the market. Keep only those ewes who meet your benchmark for performance.
A good rule of thumb is that ewe lambs should weigh at least 70% of their mature weight at breeding. Lambs should be managed so that they are not excessively fat because fat will accumulate in the udder and decrease overall milk production. If lambs are thin, flush them with either high quality pasture or feed a grain supplement. Corn is probably the most widely used supplemental feed and can be fed at a rate of 3/4 to 1 1/4 lb. per head per day. Research has shown that this increased energy will improve body condition and can lead to increased ovulation rates and result in increased lambing percentages. Flushing should start approximately two weeks prior to the breeding season and continue for four weeks after the ram is turned out with the ewe lambs.
Feeding ewe lambs during the early part of gestation is relatively the same as feeding them before breeding season. The most important time for feeding ewe lambs will occur during the last third of gestation. At this time the lamb or lambs gain most of their weight prior to birth. So, ewe lambs require nutrition to support this growth as well as their own continued growth. Bred ewe lambs should be gradually switched over to higher quality forage at this time. Ewe lambs may also require a grain supplement, depending on their body condition and the nutritional value of the forage. Nutrient dense feeds are very important at this point because the lambs will take up a large amount of space inside the ewe, which will limit how much she can eat. Poor nutrition can lead to problems such as pregnancy disease, weak or lighter birth weight lambs, and decreased milk production.
Ideally, ewe lambs should be separated from the mature ewes during the last part of gestation. Some producers breed ewe lambs later than the mature ewes. This can allow producers to manage the ewes as one large group for a short period of time. Ewe lambs receive higher nutrition throughout the pregnancy to support their growth while the mature ewes receive higher nutrition only during the last part of gestation. Once all the mature ewes have lambed, the ewe lambs continue to receive higher levels of nutrition throughout the last part of their gestation and then throughout the period of time they nurse their lamb or lambs. Bear in mind that adequate feeder space must be provided so that ewe lambs are not pushed away from feed by the larger mature ewes. If adequate feeder space is not available, then manage the ewe lambs as a group separate from the mature ewes to insure they receive adequate nutrition.
These ewes lambs are grouped separately from mature ewes to insure that they receive additional nutrition to support their growth as well as that of their lambs.
When ewe lambs are bred to lamb later than mature ewes, this also gives producers an opportunity to spend more time with ewes lambing for the first time. In some cases, they may not be as aggressive at mothering as an older ewe. One of the most aggravating tasks for me at lambing time is to have an older ewe that has not lambed yet, try to take a lamb away from a young ewe. So, if all the mature ewes have already lambed, this pretty well eliminates this problem. Young ewes have a better opportunity to mother their lamb without getting bullied!
Not all producers breed their ewe lambs. But, if you do breed ewe lambs be mindful that they are still growing themselves and require a higher plane of nutrition to support their growth and that of the lambs. Best of luck with your lambing !