Teagasc BETTER Sheep Farms - Lamb performance from birth to 7 weeks old.
Type Media Article
Weighing Lambs at 7 weeks is crucial to assessing the ewe flock and it also gives a picture as to how the lambs are performing. Frank Campion tells us how lambs on the Teagasc BETTER Sheep Farms have fared and Shane Moore from Co. Roscommon gives an update from his farm.
Lamb performance during the first weeks of life is largely driven by ewe milk production with the lamb being highly efficient in early life at turning nutrients into live weight gain. Therefore, the 7 week weights on the Teagasc BETTER sheep farms are a crucial measurement as they provide an update on how the ewe flock is performing as well as a picture of how lambs are performing. This data has both long and short term benefits. The lamb weights allow the farmer to assess current performance and what actions might need to be taken as the season moves on. They can also be used for long term breeding decisions such as picking ewe lambs from ewes that have the fastest litter growth rates to 7 weeks i.e. potentially ewe with higher milk yields. Typically the lowland flocks in the programme target to have twin born and reared lambs growing >280g/day where no supplementation is offered to the ewes or lambs after lambing.
Table 1. Lamb performance of the lowland BETTER farm flocks from birth to 7 weeks
| Birth Weight (kg) | 7 Week Weight (kg) | Growth Rate (g/day) | ||||
|---|---|---|---|---|---|---|
| Birth Type | Mean | Range | Mean | Range | Mean | Range |
| 1 | 6.2 | 5.9 - 6.6 | 23.9 | 22.6 - 26.6 | 359 | 326 - 413 |
| 2 | 5.4 | 5.1 - 5.9 | 20.0 | 18.6 - 22.7 | 299 | 275 - 343 |
| 3+* | 4.6 | 4.3 - 5.0 | 19.5 | 18.6 - 20.8 | 301 | 286 - 332 |
*Born as multiples reared as twins
The birth weights, 7 weeks weights and growth rates from birth to 7 weeks for eight of the mid-season lambing BETTER farm flocks is summarised in Table 1. These flocks began lambing between the final week of February and the 17th of March and the data presented is for mature ewes only (i.e. yearling ewe data is removed). Performance across the flocks this year is good with all of the flocks performing very close to or greater than the target in terms of growth rates and weights at 7 weeks of age. This sort of performance should allow the flocks to maintain a high level of performance up until weaning time.
The comparatively benign weather conditions for April compared to previous years combined with good grass growth and utilisation since lambing has no doubt helped lamb performance. All the flocks dosed lambs for Nematodirus using a white drench in late April/early May. They have now begun taking faecal samples for FECPAK analysis. Dosing decisions for the remainder of the year will be based on the results of FECPAK analysis in order to ensure lambs are dosed at the correct time and anthelmintic resistance is being managed on the farms.
Dry matter grass yields per hectare up until mid-May are down approximately ½ tonne DM/Ha on average compared to 2019, but is similar to the grass grown per Ha up until the same time in 2018. This difference appears to be a reflection of weather conditions earlier in the year and the exceptional winter growth experienced in the winter of 2018/19 compared to last winter. However, most of the flocks have manged to make silage in May, predominantly by dropping out surplus paddocks from the rotation based. All of the flocks are using PBI to manage grass and the data this provides allows them to make decisions such as dropping paddocks with confidence. A key element in keeping lambs thriving up to and after weaning will be to maintain high quality grass for the lambs.