The practice of lambing ewe lambs down as yearling hoggets is a specialist production system that demands that key performance indicators are met.

Failure to meet these indicators can lead to a messy situation of potentially higher mortality in lambs and hoggets, poor performance and in the worst-case scenario a batch of female replacements that will potentially have compromised lifetime performance.

Teagasc and the AFBI have carried out research in this area over the last decade, with the trials from both organisations highlighting similar lessons learned. The chances of a yearling hogget successfully rearing a lamb each is influenced by their performance during gestation. This is in turn typically dictated by the quality and quantity of feed offered.

Research shows that where ewe lambs lose weight in mid-pregnancy it can lead to higher mortality

The target daily liveweight gain for sheep during early and mid-pregnancy is in the region of 80g daily. This is in contrast to the advice for mature ewes, where a small reduction in body condition (maximum 5%) in mid-pregnancy is beneficial for placental development. Keeping ewe lambs on a steady plane of nutrition also meets the demands on their system for growth, maintenance and the developing foetus(es). AFBI research shows that where ewe lambs lose weight in mid-pregnancy it can lead to higher mortality.

Balanced feeding programme

Feeding needs to be balanced, though, as overfeeding during pregnancy can also have some negative consequences. The AFBI trial found excessive feeding in early pregnancy is more likely to lead to the birth of over-sized lambs. While over-feeding in mid-pregnancy has been shown to have negative effects on placental development and also possibly reduce a hogget’s maternal instinct at lambing.

The weather in recent weeks has been harder on sheep, with performance limited where sheep were not run on dry ground with sufficient grass supplies. For the Teagasc trial, ewe lambs were mated in October and early November, sustained on relatively good-quality grass during this period and then housed in mid-December on a diet of high-quality silage with a dry matter digestibility score of 75%.

Concentrate supplementation at a rate of 200g daily was introduced in mid-January. This was carried out to take account of a rising nutritional strain on hoggets as they progressed through gestation. The level of supplementation was increased to 250g in late January, with sheep transferred to a rising level of supplementation in later pregnancy.

Silage quality

Many sheep farms will have silage or hay of lower quality or prioritise retaining ewe lambs outdoor for longer. As touched on above, the feeding value of grass at this stage of the year and in current weather will be at a low level.

Where grass utilisation is poor and quality is mediocre, then sheep will do well to meet maintenance requirements. As such, introducing a small level of concentrates (200g to 300g) or top-quality silage will help to increase dry matter and energy intake.

Similar levels of supplementation are advised where moderate quality silage (68% to 70% DMD) or good-quality hay is the mainstay of the diet. Animals should be handled at regular intervals to ensure they remain on track, with feeding levels adjusted accordingly if required.

Keeping an eye on the performance of replacement hoggets which are run dry is also important to ensure animals are performing to their potential are capable of meeting weight targets.

Keeping these lambs in ticking along and not allowing them to lose condition will also allow these lambs to be graded in the future if required and drafted for sale when prices are at their strongest.

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