Dr. Aine O’Berry, Teagasc answered the question “How can twins have completely different genetics?” at the ICBF & Sheep Ireland Genetics Conference which took place Friday 17th of January 2020 in the Heritage Hotel, Killenard, Co. Laois with a very interesting pretension on breeding and genomics.
Making life easier at the busiest time – the potential to breed for greater lamb vigour and better mothering ability. Dr Áine O’ Brien, Teagasc.
To view Aine’s presentation click here
- Lambing time is responsible for a large proportion of labour requirement throughout the sheep farming year
- Lamb vigour and ewe mothering ability are two traits that could potentially reduce the labour requirement or time spent per ewe
- Differences exist among sire groups in the prevalence of poor lamb vigour and poor ewe mothering ability with the progeny of some sires being more vigorous shortly after birth and demonstrating greater ewe mothering ability than others.
- Work is currently on-going to include both lamb vigour and ewe mothering ability in the breeding goal for Irish sheep
A key challenge in sheep systems is the labour requirement. Lambing accounts for over 25% of the labour requirement across the sheep farming year; more than double the labour required at any other key time point (e.g., weaning, mating etc.). Therefore any measure that could potentially reduce the labour required or time spent per ewe at lambing should be considered. Lamb vigour is a measure of how long it takes a lamb to stand after birth and is measured on a five point scale where 1=very poor (i.e., the lamb is still not standing after one hour) and 5=very good (i.e., standing within 5 minutes). Ewe mothering ability is a subjective measure of the ewes behaviour towards her lamb(s) and is scored on a five point scale where 1=very poor (i.e., the ewe shows no interest in her lamb(s)) and 5=very good (i.e., the ewe is very protective, licks the lamb(s) immediately, follows lamb(s) closely and bleats for the lamb(s)). Differences existed among sire groups in the prevalence of poor lamb vigour (i.e., score 1, 2, or 3; the lamb was not standing within 30 minutes) and poor mothering ability (i.e., score 1, 2, or 3) of their progeny. All sires included in the analysis had a minimum of 30 progeny in at least two flocks. Taking lamb vigour for example, of the sires included, 0% of the progeny of 14 sires had a score of 4 or 5 for lamb vigour. In contrast, 90% of the progeny of one sire had a lamb vigour score of 1, 2, or 3 meaning these animals took at least 30 minutes to stand after birth. A similar trend was observed for ewe mothering ability. Given that management and environment were expected to be the same for progeny of all sires in the same flocks, this would indicate that genetic differences between sires accounts for most of the difference in prevalence of poor lamb vigour or mothering ability in progeny. Work is currently underway to include both of these traits in the breeding goal for Irish sheep.