Choosing the best lambs for replacements
Published 03/08/2010 | 05:00
After a long, cold and slow-growing spring, summer has brought good grass growth, with plenty of heat and dry days for silage and haymaking.
Our farm consists of 85ha in three separate divisions, with the furthest division 16km away. We are stocked with 600 mid-season ewes and replacements. All our lambs are sold to a local wholesale butcher at 20kg+ deadweight. We also have 30 autumn calving cows with all their progeny brought to beef.
Our farm is being used as a central progeny test farm for the testing of pedigree rams by the ICBF to help genetic evaluation of rams from information at lambing and on their lambs.
To do this, we sponge and AI all ewes in two groups, so we end up with two crops of lambs of a similar age. This year we used 15 rams from five different breeds -- Vendeen, Charollais, Texel, Suffolk and Belclare.
Ewes are all electronically tagged so, after birth, all lambs are tagged, weighed and correlated to their mothers' tags. There is no paperwork as all data is processed through a handheld recorder and information is sent directly to the ICBF office by email.
After birth, we weigh the lambs once at 40 days and again at weaning time, as well as scanning them for back fat.
From this information, we have picked our ewe lambs to keep as replacements for next year. For the past few years, we have not put any ewe lambs to the ram, but this year we plan to try those that reach 45-50kg in weight by late October.