It is estimated that up to about 55% of the lowland flock replacement females could give birth at one year of age.

One advantage of lambing ewe lambs is that they are not unproductive in their first year.  Also, it identifies any none breeders, i.e. those that have not been raddle marked.  Reasons not to lamb ewes at a year old include limited space with low output ewe lambs taking up space in buildings.  Also, ewe lambs need to be fed differently and so will need to be split into groups.  Some farmers chose not to do it as it extends the lambing season and more labour is needed to lamb ewe lambs.

Fertility

Both fertility and prolificacy of ewe lambs are lower, however ewes bred as lambs have a higher lifetime production rate compared with those bred as shearlings.  Also, ewe lambs that reach puberty during their first year have higher lifetime production even if they are not bred from.

Crossbred animals are more likely to reach puberty and breed in their first season than purebred animals.  Ewe lamb live weight at mating should be 60% of mature body weight (mules 45 kg and continental crosses 48kg).

Ewe lambs begin cycling later than mature ewes and their mating season is shorter in duration.  It is likely that even in well grown lambs up to 20% will not become pregnant.  Ewe lambs have a shorter heat and are more reluctant to seek out rams; therefore more rams should be used and confine animals to a small area of land.

Feeding at mating

In general, ewe lambs should have a daily live weight gain of 250g/day from weaning until 6 weeks after mating.  Very good quality grass should suffice, but offering 0.5 kg/head/day concentrates should suffice if grass is lower quality.  However heavy feeding of young females (<5 months) can impair mammary development and reduce milk yield.

Feeding during pregnancy

During early and mid pregnancy, ewe lambs require 20% more feed than mature ewes of similar weight as their bodies are still growing.  Aim for 250g/day when the rams are introduced for the first 2 months, then 6 weeks before lambing growth rate should be 150g/day.

Lambing

Mortality rate at lambing can be 1-2% higher than for mature ewes.  However, it is generally reported that ewe lambs have a better mothering ability than shearlings.  But ewe lambs should only rear single lambs as they will suffer in the following season.

Gross margins for animals that have given birth and those that have not lambed as lambs are £61.20 and £25.90 respectively.

Weaning

To get ewe lambs ready for the ram in the subsequent year, you can wean early and creep feed lambs to get them off the ewes quickly and give the ewes time to recover for the following year.