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RESEARCH ARTICLE

Higher weaning weight improves postweaning growth and survival in young Merino sheep

S. Hatcher A E , J. Eppleston B , R. P. Graham C , J. McDonald D , S. Schlunke D , B. Watt B and K. J. Thornberry A
+ Author Affiliations
- Author Affiliations

A NSW Department of Primary Industries, Orange Agricultural Institute, Forest Road, Orange, NSW 2800, Australia.

B Central Tablelands Rural Lands Protection Board, PO Box 20, Bathurst, NSW 2795, Australia.

C NSW Department of Primary Industries, PO Box 20, Yass, NSW 2582, Australia.

D Yass Rural Lands Protection Board, PO Box 10, Yass, NSW 2582, Australia.

E Corresponding author. Email: sue.hatcher@dpi.nsw.gov.au

Australian Journal of Experimental Agriculture 48(7) 966-973 https://doi.org/10.1071/EA07407
Submitted: 10 December 2007  Accepted: 13 March 2008   Published: 20 June 2008

Abstract

Two monitoring projects were conducted to investigate weaner mortality in commercial Merino flocks in the Yass and the Central Tablelands Rural Lands Protection Boards located in the Southern Tablelands agricultural region of New South Wales. The projects were conducted in Yass in 2005 and in the Central Tablelands in 2006. A random sample of weaners from four flocks in the Yass board and 11 flocks in the Central Tablelands board were regularly weighed, growth rates were calculated after weaning and survival was determined by the continuing presence of an individual weaner at subsequent weighing activities. Weaning weight was the most important factor in determining postweaning liveweight, growth rates and survival with the significant impact of weaning weight on liveweight persisting for up to 6 months after weaning. Despite the lightest weaners being capable of considerable compensatory growth given sufficient postweaning nutrition, the lightest 25% of weaners were more than twice as likely to die as heavier weaners. A focus on ewe nutrition and parasite control during late pregnancy and lactation will allow Merino producers to achieve higher weaning weights that will set their weaners up for strong postweaning growth with a decreased likelihood of mortality.


Acknowledgements

We wish to acknowledge the support and enthusiasm of the owner/managers of the commercial properties involved in the both the Yass and Central Tablelands RLPBs. Without their cooperation, enthusiasm and support this project would not have been possible. Other RLPB staff, NSW Department of Primary Industries support staff and University of Sydney Veterinary interns provided additional technical assistance as required during the scheduled monitoring activities on each property. The Central Tablelands monitoring project was sponsored by Pfizer’s Eryvac vaccine and received some financial support from Lifetime Wool project, a national project supported by Australian Wool Innovation Ltd, Department of Primary Industries Victoria, Department of Agriculture and Food Western Australia, NSW Department of Primary Industries, Tasmanian Department of Primary Industries and Water, South Australian Research and Development Institute, CSIRO, Austral Park: Coleraine, Billandri Poll Merino Stud, Kendenup and over 120 wool producers across southern Australia.


References


Allden WG (1968) Undernutrition of the Merino sheep and its sequelae. III. The effect on lifetime productivity of growth restrictions imposed at two stages of early post-natal life in a Mediterranean environment. Australian Journal of Agricultural Research 19, 981–996.
Crossref | GoogleScholarGoogle Scholar | open url image1

Allden WG (1970) The body composition and herbage utilization of grazing Merino and crossbred lambs during periods of growth and summer undernutrition. Australian Journal of Agricultural Research 21, 261–272.
Crossref | GoogleScholarGoogle Scholar | open url image1

Atkins KD , Richards JS , Semple SJ (2006) The application of genetic principles to precision production systems in sheep. In ‘8th world congress on genetics applied to livestock production’. (CD-ROM) Paper 05–01.

Bennetts HW (1958) Unthriftiness of weaner sheep in Western Australia. Australian Veterinary Journal 34, 398–401.
Crossref | GoogleScholarGoogle Scholar | open url image1

Campbell AJD , Vizard AL , Larsen JWA (2007) Quantified estimates of risk factors for post-weaning mortality of weaner Merino sheep in south-eastern Australia. In ‘Proceedings of the Society for Veterinary Epidemiology & Preventive Medicine’. pp. 75–83.

Cobon DH, O’Sullivan PD, Connelly PT (1990) The effect of management strategies on the productivity of weaner sheep in north-west Queensland. Animal Production in Australia 18, 466. open url image1

Doyle PT, Egan JK (1983) The utilization of nitrogen and sulfur by weaner and mature merino sheep. Australian Journal of Agricultural Research 34, 433–439.
Crossref | GoogleScholarGoogle Scholar | CAS | open url image1

Egan JK, Doyle PT (1982) The effect of stage of maturity in sheep upon intake and digestion of roughage diets. Australian Journal of Agricultural Research 33, 1099–1105.
Crossref | GoogleScholarGoogle Scholar | open url image1

Engel AE (1958) Unthriftiness of weaner sheep in south-western Victoria. Australian Veterinary Journal 34, 391–397.
Crossref | GoogleScholarGoogle Scholar | open url image1

Ferrell CL, Koong LJ, Nienaber JA (1986) Effect of previous nutrition on body composition and maintenance energy costs of growing lambs. The British Journal of Nutrition 56, 595–605.
Crossref | GoogleScholarGoogle Scholar | CAS | PubMed | open url image1

Foot JZ, McIntyre JS, Heazlewood PG (1983) Supplements for Merino weaner sheep grazing mature pastures in summer and autumn. Australian Journal of Experimental Agriculture and Animal Husbandry 23, 374–382.
Crossref | GoogleScholarGoogle Scholar | open url image1

Gilmour AR , Gogel BJ , Cullis BR , Welham SJRT (2002) ‘ASReml User Guide Release 1.0.’ (VSN International Ltd: Hemel Hempstead, UK)

Harris DJ, Nowara G (1995) The characteristics and causes of sheep losses in the Victorian Mallee. Australian Veterinary Journal 72, 331–340.
Crossref | GoogleScholarGoogle Scholar | CAS | PubMed | open url image1

Hatcher S , Graham P , Nielsen S , Gilmour AR (2007) Maiden Merino ewe conception rates. NSW Department of Primary Industries Primefact 308.

Hegarty RS, Neutze SA, Oddy VH (1999) Effects of protein and energy supply on the growth and carcass composition of lambs from differing nutritional histories. The Journal of Agricultural Science 132, 361–375.
Crossref | GoogleScholarGoogle Scholar | open url image1

Holst PJ, Hall DG, Stanley DF, Nolan JV (1997) Effects of sex and liveweight on feeding behaviour of crossbred weaner lambs receiving oaten grain supplement on lucerne pasture. Australian Journal of Experimental Agriculture 37, 611–615.
Crossref | GoogleScholarGoogle Scholar | open url image1

Hutchinson KJ, McRae BH (1969) Some factors associated with the behaviour and survival of newly shorn sheep. Australian Journal of Agricultural Research 20, 513–521.
Crossref | GoogleScholarGoogle Scholar | open url image1

Kellaway RC (1973) The effects of plane of nutrition, genotype and sex on growth, body composition and wool production in grazing sheep. The Journal of Agricultural Science 80, 17–27.
CAS |
open url image1

Knox MR, Besier RB, Carmichael IH, Steel JW (2006) Nutrition for parasite management. International Journal of Sheep and Wool Science 56, 14–21. open url image1

McLaughlin JW (1973) Management of weaner sheep in western Victoria. 2. The effects of supplements of oat grain or pasture hay or the periodic grazing of a green fodder crop upon current and subsequent production. Australian Journal of Experimental Agriculture and Animal Husbandry 13, 637–642.
Crossref | GoogleScholarGoogle Scholar | open url image1

McManus WR, Kennedy TG (1972) Supplementary feeding of grazing Merino ewe weaners. Australian Journal of Experimental Agriculture and Animal Husbandry 12, 584–588.
Crossref | GoogleScholarGoogle Scholar | open url image1

McManus WR, Reynolds JA, Roberts EM (1973) Whole wheat grain feeding of lambs. 2. Growth of Merino lambs early weaned onto wheat. Australian Journal of Agricultural Research 24, 413–423.
Crossref | GoogleScholarGoogle Scholar | CAS | open url image1

McManus WR, Arnold GW, Dudzinski ML, Gharaybeh HR (1974) Body composition of young sheep. 3. Effect of intake and pasture species on body composition and ruminal development of Merino lambs. Australian Journal of Experimental Agriculture and Animal Husbandry 14, 604–612.
Crossref | GoogleScholarGoogle Scholar | CAS | open url image1

Mulhearn CJ (1958) Unthriftiness of weaner sheep in South Australia. Australian Veterinary Journal 34, 383–390.
Crossref | GoogleScholarGoogle Scholar | open url image1

Mulholland JG , Black JL , Scarlett EC (1984) Application of nutritional principles to field problems. Australian Wool Corporation – Wool Research Trust Fund, Final Report No. Project K/1/1093.

Norris RT (1986) Survey of post-weaning management, growth and mortality of Merino weaners. Western Australian Department of Agriculture Technical Bulletin. p. 32. Western Australian Department of Agriculture, South Perth.

Norton BW, Hales JW, Stockwell TGH (1990) Reproduction, growth and survival of Merino ewes and lambs in south-western Queensland and their response to trace element supplementation. Australian Journal of Experimental Agriculture 30, 155–163.
Crossref | GoogleScholarGoogle Scholar | open url image1

Rose M (1972) Vital statistics for an experimental flock of Merino sheep in north-west Queensland. Proceedings of the Australian Society of Animal Production 9, 48–54. open url image1

Sackett D , Holmes P , Abbott K , Jephcott S , Barber M (2006) Assessing the economic cost of endemic disease on the profitability of Australian beef cattle and sheep producers. Meat & Livestock Australia, Final Report No. AWH.087, North Sydney.

Stephenson RGA, Pritchard DA, Pepper PM, Connelly PT (1985) The effect of different pasture management strategies in north-west Queensland on liveweight gain and wool growth rate of several groups of young sheep. Australian Rangelands Journal 7, 75–79.
Crossref | GoogleScholarGoogle Scholar | open url image1

Thornton RF, Hood RL, Jones PN, Re VM (1979) Compensatory growth in sheep. Australian Journal of Agricultural Research 30, 135–151.
Crossref | GoogleScholarGoogle Scholar | CAS | open url image1

White A Holst P (2006) Fat scoring sheep and lambs, NSW Department of Primary Industries Primefact 302.