Genetic and nutritional regulation of lamb growth and muscle characteristics
R. S. Hegarty A D , R. D. Warner B and D. W. Pethick CA Beef Industry Centre of Excellence, NSW Department of Primary Industries, Armidale, NSW 2351, Australia.
B Department of Primary Industries, 600 Sneydes Road, Werribee, Vic. 3030, Australia.
C School of Veterinary and Biomedical Science, Murdoch University, Murdoch, WA 6150, Australia.
D Corresponding author. Email: roger.hegarty@dpi.nsw.gov.au
Australian Journal of Agricultural Research 57(6) 721-730 https://doi.org/10.1071/AR06105
Submitted: 4 April 2006 Accepted: 17 May 2006 Published: 20 June 2006
Abstract
Combined actions of nutrition and genetic regulation of the growth rate of lambs as well as the physical, biochemical, and eating quality characteristics of their skeletal muscle were assessed in a major field experiment. Data arising were collated and integrated to consolidate findings made at the farm, animal, tissue, cellular, and gene expression levels. At the farm level, increased nutrient availability significantly increased the growth rate of crossbred lambs and increased the growth advantage resulting from the use of sires with high estimated breeding values (EBV) for growth. In contrast, the extra depth of the M. longissimus thoracis et lumborum (EMD) arising from sires with a higher EBV for this trait was constant irrespective of nutrition. Ewe liveweight and body condition were critical in determining the pre-weaning nutrition and growth of lambs, with the LOW plane of nutrition causing stunting of forelimb bones and changes to the allometric growth coefficients for carcass lean and fat. The EBV of the sire for muscling (PEMD) influenced several non-muscling traits, and interactions with nutrition suggested that on HIGH nutrition, absorbed nutrients were partitioned away from wool and fat accretion and towards protein accretion in lambs having superior muscling genetics. Expression levels of known myogenic factors in muscle, together with a suite of peptides and proteins whose identity and levels were determined by proteomic screening, contributed to improved understanding of the mechanisms underpinning nutritional and genetic regulation of skeletal muscle development. The study revealed the need for caution in the use of indirect markers of growth or composition, with their usefulness being constrained if the localisation of the response to selection is specific to parts of the carcass where the selection had initially been concentrated. As well, the possibility that much of the variation explained by potential physiological markers can be accounted for by non-invasive measures of growth and fatness currently used by Australian farmers must be considered.
Additional keywords: genetic potential, gene expression, undernutrition, lamb, proteomics.
Acknowledgments
The research reported in this manuscript was supported by Meat and Livestock Australia and by the Sheep Industry Cooperative Research Centre. Semen used was donated by the source studs and this contribution is acknowledged with thanks. Particular thanks go to technical staff at the NSW Beef Industry Centre for assisting in the conduct of the field experiment and analysis and to the other scientists and laboratories who have completed analysis of samples from this experiment and whose results are reported in this volume. Dr David Hopkins is thanked for his enthusiasm and persistence in assisting authors to submit material for this volume, and Roger Hegarty thanks his co-authors and Dr Rob Banks for their committed managerial support for this collaborative research initiative.
Adams NR, Cronjé PB
(2003) A review of the biology linking fibre diameter with fleece weight, liveweight, and reproduction in Merino sheep. Australian Journal of Agricultural Research 54, 1–10.
| Crossref | GoogleScholarGoogle Scholar |
Allingham PG,
Gardner GE,
Taylor M,
Hegarty RS, Harper GS
(2006) Effects of sire genotype and plane of nutrition on fascicular structure of M. longissimus thoracis et lumborum and its effect on eating quality. Australian Journal of Agricultural Research 57, 641–650.
Andrews RP, Ørskov ER
(1970) The nutrition of the early weaned lamb. 2. The effect of dietary protein concentration, feeding level and sex on body composition at two live weights. Journal of Agricultural Science, Cambridge 75, 19–26.
Arthur PF,
Archer JA,
Johnston DJ,
Herd RM,
Richardson EC, Parnell PF
(2001) Genetic and phenotypic variance and covariance components for feed intake, feed efficiency, and other postweaning traits in Angus cattle. Journal of Animal Science 79, 2805–2811.
| PubMed |
Cake MA,
Gardner GE,
Hegarty RS,
Boyce MD, Pethick DW
(2006) Effect of nutritional restriction and sire genotype on forelimb bone growth and carcass composition in crossbred lambs. Australian Journal of Agricultural Research 57, 605–616.
Fogarty NM,
Safari E,
Taylor PJ, Murray W
(2003) Genetic parameters for meat quality and carcass traits and their correlation with wool traits in Australian Merino sheep. Australian Journal of Agricultural Research 54, 715–722.
| Crossref | GoogleScholarGoogle Scholar |
Gardner GE,
Pethick DW,
Greenwood PL, Hegarty RS
(2006) The effect of genotype and plane of nutrition on the rate of pH decline in lamb carcasses and the expression of metabolic enzymatic markers. Australian Journal of Agricultural Research 57, 661–670.
Gardner GE,
Jacobs RH, Pethick DW
(2001) The effect of magnesium oxide supplementation on muscle glycogen metabolism before and after exercise and at slaughter in sheep. Australian Journal of Agricultural Research 52, 723–729.
| Crossref | GoogleScholarGoogle Scholar |
Goodson KJ,
Miller RK, Savell JW
(2001) Carcass traits, muscle characteristics, and palatability attributes of lambs expressing the callipyge phenotype. Meat Science 58, 381–387.
| Crossref | GoogleScholarGoogle Scholar |
Greenwood PL,
Gardner GE, Hegarty RS
(2006a) Lamb myofibre characteristics are influenced by sire estimated breeding values and pastoral nutritional system. Australian Journal of Agricultural Research 57, 627–639.
| Crossref |
Greenwood PL,
Gardner GE, Hegarty RS
(2006b) Indices of cellular development in muscles of lambs are influenced by sire estimated breeding values and pastoral nutritional system. Australian Journal of Agricultural Research 57, 651–659.
| Crossref |
Hall DG,
Gilmour AR,
Fogarty NM, Holst PJ
(2002) Growth and carcass composition of second cross lambs. 2. Relationship between estimated breeding values of sires and their progeny performance under fast and slow growth regimes. Australian Journal of Agricultural Research 53, 1341–1348.
| Crossref | GoogleScholarGoogle Scholar |
Hegarty RS,
Hopkins DL,
Farrell TC,
Banks R, Harden S
(2006b) Effects of available nutrition and sire breeding values for growth and muscling on the development of crossbred lambs. 2: Composition and commercial yield. Australian Journal of Agricultural Research 57, 617–626.
Hegarty RS,
McFarlane JR,
Banks R, Harden S
(2006c) Association of plasma metabolites and hormones with the growth and composition of lambs as affected by nutrition and sire genetics. Australian Journal of Agricultural Research 57, 683–690.
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. Journal of Agricultural Science, Cambridge 132, 361–375.
| Crossref | GoogleScholarGoogle Scholar |
Hegarty RS,
Shands C,
Marchant R,
Hopkins DL,
Ball AJ, Harden S
(2006a) Effects of available nutrition and sire breeding values for growth and muscling on the development of crossbred lambs. 1: Growth and carcass characteristics Australian Journal of Agricultural Research 57, 593–603.
Hopkins DL, Fogarty NM
(1998) Diverse lamb genotypes. 2. Meat pH, colour and tenderness. Meat Science 49, 477–488.
| Crossref | GoogleScholarGoogle Scholar |
Hopkins DL,
Hegarty RS, Farrell TC
(2005) Relationship between sire EBV’s and the meat and eating quality of meat from their progeny grown on two planes of nutrition. Australian Journal of Experimental Agriculture 45, 525–533.
| Crossref | GoogleScholarGoogle Scholar |
Kimball SR,
O’Malley JP,
Anthony JC,
Crozier SJ, Jefferson LS
(2004) Assessment of biomarkers of protein anabolism in skeletal muscle during the life span of the rat: sarcopenia despite elevated protein synthesis. American Journal of Physiology, Endocrinology and Metabolism 287, E772–E780.
| Crossref | GoogleScholarGoogle Scholar |
Ledward DA, Shorthose WR
(1971) A note on the haem pigment concentration of lamb as influenced by age and sex. Animal Production 13, 193–195.
Lewis RM,
Emmans GC, Simm G
(2006) Describing effects of genetic selection, nutrition, and their interplay in prime lambs using growth and efficiency functions. Australian Journal of Agricultural Research 57, 707–719.
McDonagh MB,
Ferguson KL,
Bacic A,
Gardner GE, Hegarty RS
(2006) Variation in protein abundance profiles in the M. semitendinosus of lambs bred from sires selected on the basis of growth and muscling potential. Australian Journal of Agricultural Research 57, 671–682.
Nattrass GS,
Quigley SP,
Gardner GE,
Bawden CS,
McLaughlan CJ,
Hegarty RS, Greenwood PL
(2006) Genotypic and nutritional regulation of gene expression in two sheep hindlimb muscles with distinct myofibre and metabolic characteristics. Australian Journal of Agricultural Research 57, 691–698.
Pálsson H, Vergés JB
(1952) Effects of the plane of nutrition on growth and the development of carcass quality in lambs. Part 1. The effects of high and low planes of nutrition at different ages. Journal of Agricultural Science, Cambridge 42, 2–92.
Pethick DW,
Banks RG,
Hales J, Ross IR
(2006) Australian prime lamb – a vision for 2020. International Journal of Sheep and Wool Science 54, 66–73.
Suzuki A
(1973) Histochemical observations of individual skeletal muscle fibers in starved sheep. Japanese Journal of Zootechnical Science 44, 50–58.
Walkley JRW,
Ponzoni RW, Dolling CHS
(1987) Phenotypic and genetic parameters for lamb and hogget traits in a flock of South Australian Merino sheep. Australian Journal of Experimental Agriculture 27, 205–210.
| Crossref | GoogleScholarGoogle Scholar |
Wood JD, Macfie HJ
(1980) The significance of breed in the prediction of lamb carcass composition from fat thickness measurements. Animal Production 31, 315–319.
