The battle for sheep breeding is won or lost in the preparations that are put in place in advance of breeding. Ewe prolificacy and stocking rate are the two key drivers of potential profit on a farm. Prolificacy is influenced by genetics but also by ewe nutrition.

Teagasc research shows a strong relationship between the liveweight and body condition score (BCS) of ewes and subsequent litter size. For lowland ewes, each one-unit increase in BCS within a range of 2.5 to 4 has the potential to increase litter size by 0.13 lambs. Mating ewes under BCS 2.5 will significantly increase the barren rate. It will take eight to 10 weeks on good grass for ewes to gain one condition score (10kg to 12kg in lowland breeds) raising the importance of monitoring condition.

For hill ewes, increasing from a BCS of 2 to 3 has the ability to increase the lambing percentage by some 13.5%. Experience through the Teagasc BETTER farm sheep programme shows a difference in pregnancy rate of over 10% between ewes at the desired condition score of 3+ at joining and those falling well below target with a BCS of 2.

Breeding ewe lambs is touched upon here. Teagasc research shows ewe lambs should weigh at least 61% of mature weight at breeding, hoggets should weigh at least 84% of mature weight and 30-month sheep should weigh at least 91%. Lowland breeds such as Suffolk and Texel cross have a mature weight ranging anywhere from 75kg to in excess of 90kg. Belclare and Lleyn crosses are 5kg to 10kg lower, while there is a wide variation in Mules from 70kg to at least 90kg.

The mature weight of Scottish Blackface ewes also differs between regions and the strain of Scottish Blackface ewes. On harder hills, the mature weight of smaller-framed Scottish Blackface ewes ranges from 47kg to 52kg, while larger-framed ewes on more productive lands can weight up to 60kg to 65kg mature weight.