Update August-September 2017
Philip Creighton, Animal and Grassland Research and Innovation Centre, Teagasc Athenry, Co Galway.
On a stocking rate basis, 25% of lambs have been drafted from the 11 ewes/ha groups with 15% from the 13 ewes/ha groups up to mid-August. There is approximately 5% more lambs drafted from the grass clover treatments compared to the grass only pasture treatments. Average liveweight for lambs drafted to date (August 16th) was 43.8 kg with average carcase weight 18.8 kg. This represents an average kill out percentage of 43%. Kill out over the last month has been disappointing with kill out percentages as low as 41% recorded. Lamb growth rates for the past month have been in the region of 165g/day (grass only) to 175g/day (grass + white clover) although this has been variable with growth as low as 120g/day recorded in early August. This corresponded with the period of very poor weather conditions and we also observed a very rapid rise in parasite burden in lambs with egg counts rising to as high as 2000 eggs per gram from 100-200 two weeks previously in early August. Grass growth rates have been strong averaging 50-70 kg DM/ha/day. To date 113kg N/ha of the 145kg N/ha total allowance for the grass only and grass + white clover high nitrogen treatments has been spread and 78kg N/ha of the 90kg N/ha allowance for the grass + white clover low nitrogen treatments has been spread. Final applications of between 12 to 32 kg N/ha (depending on treatment) will be applied in late August/early September. Maintenance dressings of K are also being applied based on soil test results. Up to mid-August total grass grown (grazing and silage) on the grass only treatments was 9.1 tons DM/ha with 9.2 tons DM/ha grown in the grass + white clover treatments. The grass + white clover high nitrogen treatments grew 9.3 tons DM/ha and the grass + white clover low nitrogen treatments grew 9.1 tons DM/ha.