The Benefits of Retaining Your Own Replacement Ewes
Joanne Masterson and Damian Costello discuss the Kerrigan family's strategy for retaining home-bred ewe lambs to reduce disease risk, improve genetics, and optimize flock management on their organic hill farm in Galway.
Retaining home-bred ewe lambs not only reduces the risk of bringing in unwanted disease issues but also provides the opportunity to fully exploit genetic improvement, say Martin Joe and Martin Kerrigan. The father-and-son partnership from Galway select replacements at weaning, choosing well-grown lambs from the top-performing ewes in their organic hill flock.
The progeny of any ewe that has had issues around lambing, such as poor milk supply or poor mothering ability, are not considered for replacement. Since the parentage of these replacements is recorded, inbreeding can be avoided when these lambs reach 19 months and join the ram.
Once replacements are selected, the remaining ewe lambs were in high demand this year and were sold at special breeding sales in Maam Cross and Ballinrobe. It was also a successful year at the ram breeding sales, with SIS-approved hogget rams and ram lambs fetching excellent prices. The remaining lambs not suitable for breeding were sold as stores.
Martin Joe and Martin manage 220 Mayo/Connemara Blackface ewes, 40 replacement ewe hoggets, and six stock rams on 133 hectares (329 acres) of good-quality, mineral-type enclosed hill grazing at Glentrague near Clonbur, along with an additional 10 hectares of semi-improved and improved grazing in the foothills.
The valley of Glentrague is in the heart of "Joyce Country" and overlooks the picturesque Lough Mask. The farm has been in the family for generations, with Martin Joe taking over from his father in the early 1990s. Recently, Martin joined as a joint flock owner.
Flock Performance 2024
Data collection was nothing new to the Kerrigans when they joined the BETTER farm programme earlier this year. Following the establishment of a flock book for the Mayo/Connemara Blackface sheep, they have been working closely with Sheep Ireland as part of the recording group for purebred status. At the start of mating, each ram’s EID is linked to its ewe group in a single-sire mating system. When a ewe lambs, scanning her EID tag with the handheld device immediately identifies the sire. The progeny are then EID-tagged (usually within 24 hours of birth) and linked to the dam, providing full parentage details. Birth weight and sex are also recorded. Different coloured management discs are inserted at tagging to identify lambs by sire, which serves as a useful management tool.
All lambs were weighed and recorded by BETTER farm programme technician Jonathan Molloy at seven weeks and again at weaning (14 weeks). Single-rearing ewes and their lambs primarily grazed on the hill, while approximately 25% of the ewe flock rearing twins stayed on improved grassland until weaning. The ‘singles’ averaged 3.9 kg at birth and 22.5 kg at weaning, for an average daily weight gain of 190 g. For twins, the equivalent figures were 3.1 kg, 20.7 kg, and 180 g.
Further analysis of weaning weights showed a uniform group of lambs: only 3% weighed under 20 kg at weaning, with 27% in the 20–25 kg range, 54% in the 25–30 kg range, and 16% over 30 kg.
Ewe Management Post-Weaning
All ewes underwent their annual fitness check for breeding after weaning, including checks on udders, teeth, body condition score, and feet, with culls identified. Ewes with issues recorded during the year, such as prolapse, were also selected for culling using the handheld device.
The cull ewes, including some thin ones, were sold shortly after weaning, and the remaining ewes returned to the hill until the breeding season. This allows the low ground to rest, building up grass cover for breeding. The plan is to turn out the rams in mid-November. Ewes will have their body condition scores recorded before being divided into mating groups in the days leading up to introducing the rams.
This article was first published in the Irish Independent