Lambing ewe lambs

The advantages of lambing ewe lambs after the main flock are:

• It allows more time for ewe lambs to grow and mature
• There is a positive effect of reduced day length on ewe lamb fertility
• Increased availability of labour to aid immature ewes at lambing time

However, lambing ewe lambs when the rest of the flock has finished also has some disadvantages:

• Newly lambed mature ewes with single lambs are not available for adopting lambs from ewe lambs that produced twins
• To join the main flock in the following production year, ewe lambs need to ‘catch up’, meaning the timing of weaning is crucial

The need for assistance is common and higher neonatal mortality is often recorded in immature ewes. Difficult births caused by large single lambs can be a problem if the sheep are overfed and/or the sire has predisposed the lambs to heavy birth weights and large forequarters.

At lambing time, the mortality rate is generally 1–2% higher for ewe lambs than for mature ewes. However, lambing sheep as ewe lambs is unlikely to have any harmful effect on future performance, except if they are damaged while giving birth.

Ewe lambs that breed successfully in their first year have higher lifetime performance.

Milk production of first-time lambing ewes is generally lower than for ewes in later lactations. The lower milk yield of ewe lambs, coupled with the need for continued growth in lactation, means that ewe lambs should only rear one lamb to achieve a satisfactory liveweight gain during their second grazing season.

A supply of frozen colostrum taken from mature ewes on the farm should be available.

Lack of colostrum, together with the common practice of lambing ewe lambs after the main flock, demands high standards of hygiene because disease-causing organisms tend to build up in the environment as lambing progresses.

Ewe lambs are more prone to mastitis. The udder of ewe lambs is relatively tender and teats are more easily damaged by the teeth of suckling lambs.

As in pregnancy, lactating ewe lambs require about 20% more feed than mature ewes of a similar weight to supply sufficient nutrients for body growth.

Lactating ewe lambs should be kept as a separate group, at least until their lambs are weaned. A plentiful supply of good quality spring grass can suffice, but careful ration formulation is needed if the sheep are kept indoors or if grass is in short supply.

If grass is scarce, feed hay or silage to appetite, along with concentrate feed (ME 12.5 MJ/kg dry matter [DM], crude protein [CP] 18%) at a daily rate per head of 0.5 kg and 0.7 kg for ewe lambs suckling singles and twins, respectively.

A high-energy product (ME 12.5 MJ/kg DM) with a crude protein content of 18% is needed until eight weeks of age. After this, the protein content in the creep feed can be dropped to 15–16%.

The high nutrient demand for growth (6–7 MJ for a daily gain of 200 g) in lactating ewe lambs means their offspring should be weaned at a relatively young age – certainly before they are 12 weeks old.

Early weaning at 8–9 weeks of age could be the best option if ewe lambs (or their lambs) are in poor condition or are smaller than expected. However, good intakes of creep feed by the lambs is essential.

A poor supply of grazing is another reason to wean early.

Weaning at 8–9 weeks of age should be done abruptly when at least 250 g of creep is eaten per lamb/day over 3–4 days. After weaning, continue feeding the creep feed (ME 12.5 MJ/kg DM, CP 16–17%), or dilute by adding 30–40% barley, or change to a home-mixed ration (ME 12.5 MJ/kg DM, CP 15–16%).