Season and reproductive status rather than genetics factors influence change in ewe weight and fat over time. 1. Analysis of crossbred ewes
S. F. Walkom A B E , F. D. Brien A B C , M. L. Hebart B , N. M. Fogarty A D , S. Hatcher A D and W. S. Pitchford BA Cooperative Research Centre for Sheep Industry Innovation, Armidale, NSW 2351, Australia.
B School of Animal and Veterinary Sciences, University of Adelaide, Roseworthy Campus, SA 5371, Australia.
C South Australian Research and Development Institute, Roseworthy, SA 5371, Australia.
D New South Wales Department of Primary Industries, Orange Agricultural Institute Forest Road, Orange, NSW 2800, Australia.
E Corresponding author. Email: samuel.walkom@adelaide.edu.au
Animal Production Science 54(6) 802-813 https://doi.org/10.1071/AN13247
Submitted: 14 June 2013 Accepted: 27 February 2014 Published: 11 April 2014
Abstract
The Australian sheep industry has historically made rapid advances in the quality and quantity of meat and wool through genetic improvement, but unfortunately, maternal performance, i.e. number of lambs weaned, is well below desired levels. The aim of the present paper is to investigate the potential to select for increased weight and fat across the production cycle to improve maternal performance. The analysis explores the potential to improve the weight and fat score of breeding ewes during ‘tough’ periods (i.e. when nutrient requirements are not met by the pasture), preparing the breeding ewe for the upcoming mating without an increase in overall ewe size. The 2846 ewes within the maternal central progeny test were weighed and scored for fatness 12 times across three production cycles. Low to moderate heritability estimates for weight (0.04–0.23) and fat (0.02–0.06) changes across the production cycle provide little hope for selection against weight loss during tough periods. The analysis showed very strong genetic correlations between time-points across multiple production cycles for both weight (0.99–0.93) and fat score (0.88–0.98). The very strong correlations between measurements suggest that weight and fat score are genetically the same trait throughout the ewe’s adult life. With 74% and 77% of the genetic variation in weight and fat, respectively, constant across the production cycle, there is little opportunity to select against the natural fluctuations in weight and fat reserves. In conclusion, selection for increased fat can be made at any time and it will result in more fat during tough times.
References
Arango JA, Cundiff LV, Van Vleck LD (2002) Genetic parameters for weight, weight adjusted for body condition score, height, and body condition score in beef cows. Journal of Animal Science 80, 3112–3122.Cameron ND, Curran MK (1995) Genotype with feeding regime interaction in pigs divergently selected for components of efficient lean growth rate. Animal Science 61, 123–132.
| Genotype with feeding regime interaction in pigs divergently selected for components of efficient lean growth rate.Crossref | GoogleScholarGoogle Scholar |
Carrick MJ, van der Werf JHJ (2007) Sire by environment interaction in sheep may re-rank sires for some traits. In ‘Proceedings of the 17th biannual conference of the Association for the Advancement of Animal Breeding and Genetics, Armidale, NSW. pp. 248–251. (Association for the Advancement of Animal Breeding Genetics). Available at http://www.aaabg.org/livestocklibrary/2007/carrick248.pdf. [Verified 27 February 2014]
Chilliard Y, Ferlay A, Faulconnier Y, Bonnet M, Rouel J, Bocquier F (2000) Adipose tissue metabolism and its role in adaptations to undernutrition in ruminants. The Proceedings of the Nutrition Society 59, 127–134.
| Adipose tissue metabolism and its role in adaptations to undernutrition in ruminants.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3cXktF2gsrY%3D&md5=c7f5fea3b611436c8dac19314d4d47e6CAS | 10828182PubMed |
Coop IE (1962) Liveweight-productivity relationships in sheep. New Zealand Journal of Agricultural Research 5, 249–264.
| Liveweight-productivity relationships in sheep.Crossref | GoogleScholarGoogle Scholar |
Curnow M, Oldham CM, Behrendt R, Gordon DJ, Hyder MW, Rose IJ, Whale JW, Young JM, Thompson AN (2011) Successful adoption of new guidelines for the nutritional management of ewes is dependent on the development of appropriate tools and information. Animal Production Science 51, 851–856.
| Successful adoption of new guidelines for the nutritional management of ewes is dependent on the development of appropriate tools and information.Crossref | GoogleScholarGoogle Scholar |
Fogarty NM (1995) Genetic parameters for live weight, fat and muscle measurements, wool production and reproduction in sheep: a review. Animal Breeding Abstracts 63, 101–143.
Fogarty NM, Ingham VM, Gilmour AR, Cummins LJ, Gaunt GM, Stafford J, Edwards JEH, Banks RG (2005a) Genetic evaluation of crossbred lamb production. 1. Breed and fixed effects for birth and weaning weight of first-cross lambs, gestation length, and reproduction of base ewes. Australian Journal of Agricultural Research 56, 443–453.
| Genetic evaluation of crossbred lamb production. 1. Breed and fixed effects for birth and weaning weight of first-cross lambs, gestation length, and reproduction of base ewes.Crossref | GoogleScholarGoogle Scholar |
Fogarty NM, Ingham VM, McLoad L, Morgan J, Gaunt GM (2005b) Dynamic dams for lamb production: more $$$s from crossbred ewes with the right genetics. Technical Bulletin No. 50. NSW Department of Primary Industries, Orange, NSW. Available at http://www.dpi.nsw.gov.au/agriculture/livestock/sheep/breed-select/meat/dams. [Verified 20 March 2014]
Freer M, Moore AD, Donnelly JR (1997) GRAZPLAN: decision support systems for Australian grazing enterprises – II. The animal biology model for feed intake, production and reproduction and the GrazFeed DSS. Agricultural Systems 54, 77–126.
| GRAZPLAN: decision support systems for Australian grazing enterprises – II. The animal biology model for feed intake, production and reproduction and the GrazFeed DSS.Crossref | GoogleScholarGoogle Scholar |
Gilmour AR, Gogel BJ, Cullis BR, Thompson R (2009) ‘ASReml user guide release 3.0.’ (VSN International: Hemel Hempstead, UK)
Gunn RG, Doney JM, Russel AJF (1969) Fertility in Scottish Blackface ewes as influenced by nutrition and body condition at mating. The Journal of Agricultural Science 73, 289–294.
| Fertility in Scottish Blackface ewes as influenced by nutrition and body condition at mating.Crossref | GoogleScholarGoogle Scholar |
Gunn RG, Doney JM, Russel AJF (1972) Embryo mortality in Scottish Blackface ewes as influenced by body condition at mating and by post-mating nutrition. The Journal of Agricultural Science 79, 19–25.
| Embryo mortality in Scottish Blackface ewes as influenced by body condition at mating and by post-mating nutrition.Crossref | GoogleScholarGoogle Scholar |
Hermesch S, Jones R, Bunter K, Gilbert H (2010) Consequences of selection for lean growth and prolificacy on sow attributes. In ‘Proceedings of the 9th world congress on genetics applied to livestock production’. 1–6 August, Leipzig, Germany. (ID292) (CD-ROM).
Kearl LC (1982) ‘Nutrient requirements of ruminants in developing countries.’ (International Feedstuffs Institute: Logan, UT)
Kenyon PR, Morel PCH, Morris ST (2004) The effect of individual liveweight and condition scores of ewes at mating on reproductive and scanning performance. New Zealand Veterinary Journal 52, 230–235.
| The effect of individual liveweight and condition scores of ewes at mating on reproductive and scanning performance.Crossref | GoogleScholarGoogle Scholar | 1:STN:280:DC%2BD2M7js1ahtA%3D%3D&md5=71dc15d5da16303309a4e8fec6fc989bCAS | 15768117PubMed |
Knap PW (2008) Robustness. In ‘Resource allocation theory applied to farm animal production’. (Ed. WM Rauw) pp. 288–301. (CABI Publishing: Wallingford, UK)
Lambe NR, Simm G, Young MJ, Conington J, Brotherstone S (2004) Seasonal changes in tissue weights in Scottish Blackface ewes over multiple production cycles. Animal Science 79, 373–385.
Lee GJ, Atkins KD, Sladek MA (2009) Heterogeneity of lifetime reproductive performance, its components and associations with wool production and liveweight of Merino ewes. Animal Production Science 49, 624–629.
| Heterogeneity of lifetime reproductive performance, its components and associations with wool production and liveweight of Merino ewes.Crossref | GoogleScholarGoogle Scholar |
Moxham RW, Brownlie LE (1976) Sheep carcase grading and classification in Australia. Wool Technology and Sheep Breeding 23, 17–25.
Napel JT, Calus MPL, Mulder HA, Veerkamp RF (2009) Genetic concepts to improve robustness of dairy cattle. In ‘Breeding for robustness in cattle’. (Eds M Klopčič, R Reents, J Philipsson, A Kuipers) (Wageningen Academic Publishers: Wageningen, The Netherlands)
Nicholls N, Drosdowsky W, Lavery B (1997) Australian rainfall variability and change. Weather 52, 66–72.
| Australian rainfall variability and change.Crossref | GoogleScholarGoogle Scholar |
Osman AH, Bradford GE (1965) Effects of environment on phenotypic and genetic variation in sheep. Journal of Animal Science 24, 766–774.
Osorio-Avalos J, Montaldo HH, Valencia-Posadas M, Castillo-Jua’rez H, Ulloa-Arvizu R (2012) Breed and breed × environment interaction effects for growth traits and survival rate from birth to weaning in crossbred lambs. Journal of Animal Science 90, 4239–4247.
| Breed and breed × environment interaction effects for growth traits and survival rate from birth to weaning in crossbred lambs.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXns1Smtw%3D%3D&md5=50eb5e9c7ff538fb3e1ae4649e7f1442CAS | 22952357PubMed |
Rauw WM, Thain DS, Teglas MB, Wuliji T, Sandstrom MA, Gomez-Raya L (2010) Adaptability of pregnant Merino ewes to the cold desert climate in Nevada. Journal of Animal Science 88, 860–870.
| Adaptability of pregnant Merino ewes to the cold desert climate in Nevada.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXktVOquro%3D&md5=23edaab65333b685c862aeff6de621bdCAS | 19933439PubMed |
Rose G, Kause A, Mulder HA, van der Werf JHJ, Thompson AN, Ferguson MB, van Arendonk JAM (2013) Merino ewes can be bred for body weight change to be more tolerant to uncertain feed supply. Journal of Animal Science 91, 2555–2565.
| Merino ewes can be bred for body weight change to be more tolerant to uncertain feed supply.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXpvFCrs7o%3D&md5=8acb7ca13e92a35ecdd4ea076136ac53CAS | 23508033PubMed |
Safari E, Fogarty NM, Gilmour AR (2005) A review of genetic parameter estimates for wool, growth, meat and reproduction traits in sheep. Livestock Production Science 92, 271–289.
| A review of genetic parameter estimates for wool, growth, meat and reproduction traits in sheep.Crossref | GoogleScholarGoogle Scholar |
Shackell GH, Cullen NG, Greer GJ (2011) Genetic parameters associated with adult ewe liveweight and body condition. In ‘Proceedings of the Association for the Advancement of Animal Breeding and Genetics conference, Perth’. pp. 103–106. (Association for the Advancement of Animal Breeding and Genetics)
Snowder GD, Fogarty NM (2009) Composite trait selection to improve reproduction and ewe productivity: a review. Animal Production Science 49, 9–16.
| Composite trait selection to improve reproduction and ewe productivity: a review.Crossref | GoogleScholarGoogle Scholar |
Trompf JP, Gordon DJ, Behrendt R, Curnow M, Kildey LC, Thompson AN (2011) Participation in Lifetime Ewe Management results in changes in stocking rate, ewe management and reproductive performance on commercial farms. Animal Production Science 51, 866–872.
| Participation in Lifetime Ewe Management results in changes in stocking rate, ewe management and reproductive performance on commercial farms.Crossref | GoogleScholarGoogle Scholar |
Vernon RG, Clegg RA, Flint DJ (1981) Metabolism of sheep adipose-tissue during pregnancy and lactation - adaptation and regulation. Biochemical Journal 200, 307–314.
Young JM, Thompson AN, Curnow M, Oldham CM (2011) Whole-farm profit and the optimum maternal liveweight profile of Merino ewe flocks lambing in winter and spring are influenced by the effects of ewe nutrition on the progeny’s survival and lifetime wool production. Animal Production Science 51, 821–833.
| Whole-farm profit and the optimum maternal liveweight profile of Merino ewe flocks lambing in winter and spring are influenced by the effects of ewe nutrition on the progeny’s survival and lifetime wool production.Crossref | GoogleScholarGoogle Scholar |