Review/Oorsig Volume 22, Issue 01 - Page 17

Volume 22 • Issue 01 • 2018 will greatly slow down resistance and then individuals needing treatment can be identified and culled. Use sound calculations to evaluate flocks. Lambing and weaning percentages must be done on ewes mated during that breeding season. Also discard any lambs not reared by ewes. In more than once a year breeding systems, ewes are often moved to the next group if she does not conceive and then lambing and weaning gets calculated on ewes pregnant and not ewes mated. For more complex selections the most efficient animals must be selected rather than the biggest producers for example using weaning efficiency rather than absolute weaning weight of lambs will ensure optimal production. Selection must also be dynamic and re-evaluation must be done annually. For a comprehensive flock evaluation, the following information is recorded: ewes mated, lambs born alive and dead per week. Lamb mortalities on weekly basis with main causes. Lambs weaned, lamb weight at weaning, ewe weight at weaning. Ewe treatments per year. General management program – dosing, dipping, footbaths and other disease control. Vaccinations. Supplements. Nutrition. Breeding management. Rams. New technology: SNP chips are currently being developed which will make selecti on for complex traits possible at an early age. However, they are not cost effective for commercial farming currently. References Precision Livestock Farming - Data and technology in farm animals; issue.com, hashogechool. AHDB Beef and Lamb – United Kingdom Meat and Livestock Australia Sheepcrc.org.au: transforming wool, meat and the sheep that produce them Sustainable sheep production and consumer preference trends: Compatibilities, contradictions, and unresolved dilemmas F. Montossi a, ⁎, M. Font-i- Furnols b , M. del Campo a , R. San Julián a , G. Brito a , C. Sañudo, Meat Science 92 (2013) Breeding ewe lambs successfully to improve lifetime performance. Kenyon, PR et al. Small ruminant research 118(2014) p2-15 Foetal programming in sheep- effects on production. Kenyon, PR and Blair, HT. Small ruminant research 118(2014) p16-30 Breeding strategies to make sheep farms resilient to uncertainty Ian James Rose Thesis committee Promotor Prof. Dr J.A.M. van Arendonk Professor of Animal Breeding and Genomics Wageningen University Co-promotor Dr H.A. Mulder Assistant professor, Animal Breeding and Genomics Centre Wageningen Universit THE VETERINARY LABORATORY DIAGNOSTIC TEAM AT YOUR SERVICE Dr Maryke Henten - BVSc, M.Med.Vet (Bacteriology) 2 Dr Rick Last - BVSc, M.Med.Vet (Pathology) 1 Dr Samantha Tompkins - BVSc, M.Med.Vet (Pathology) 2 Dr James Hill - BVSc, M.Med.Vet (Clin Pathology) 1 Dr Sandy May - BVSc, M.Med.Vet (Clin Pathology) 3 Dr Johan Vorster - BVSc, M.Med.Vet (Pathology) 1 Vetdiagnostix KZN 1 LABORATORY 257 Boshoff Street Pietermaritzburg Vetdiagnostix Gauteng 2 LABORATORY 96 Poplar Road Blue Hills, Midrand Vetdiagnostix Cape Town 3 LABORATORY 01 Kontiki Way Glen Ive, Bellville Tel: (033) 342 5014/5 (033) 342 6144 082 558 4016 074 137 9132 (Main Lab) 074 162 0559 (Main Lab) 071 563 6947 (Duty Cell) Tel: (021) 910 2243 (021) 910 1413 078 436 2560 (Duty Cell) vetdiagnostix@futurenet.co.za histocyto@vetdx.co.za vdxcape@vetdx.co.za 17