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The influence of live weight, live-weight change and diet on protein synthesis in the skin and skeletal muscle in young Merino sheep

Published online by Cambridge University Press:  09 March 2007

S. M. Liu*
Affiliation:
CSIRO Division of Animal Production and Cooperative Research Centre for Premium Quality Wool, Private Bag PO, Wembley, WA 6014, Australia
G. Mata
Affiliation:
CSIRO Division of Animal Production and Cooperative Research Centre for Premium Quality Wool, Private Bag PO, Wembley, WA 6014, Australia
H. O'Donoghue
Affiliation:
CSIRO Division of Animal Production and Cooperative Research Centre for Premium Quality Wool, Private Bag PO, Wembley, WA 6014, Australia
D. G. Masters
Affiliation:
CSIRO Division of Animal Production and Cooperative Research Centre for Premium Quality Wool, Private Bag PO, Wembley, WA 6014, Australia
*
*Corresponding author:Dr Shimin Liu, fax +618 9387 8991, email sliu@ccmar.csiro.au
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Abstract

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Wool growth is derived directly from protein synthesis in the skin of sheep, and is affected by the nutritional status of the animals. The present experiment examined both protein synthesis in the skin and muscle and wool growth in Merino lambs differing in live weight, intake and dietary protein source. The experiment was a 23 factorial design: twenty-four 5-month-old lambs initially weighing 33 kg (heavy) or 25 kg (light) were fed on a hay-based diet with either lupin seed or rapeseed meal as the major protein sources to maintain live weight (M) for 56 d, or were fed at 0.6M for 28 d (period 1) followed by 28 d at 1.6M (period 2). Fractional protein synthesis rates (FSR, % per d) in the skin and the m. longissimus dorsi on days 4 and 24 of period 1 and day 4 of period 2 were measured by means of a flooding dose of l-[ring-d5]phenylalanine, and wool growth on a skin patch over period 1 was also measured. The FSR ranged from 13.2 to 20.2% per d in the skin, higher than reported for other breeds, and 1.53–3.07% per d in the muscle. Sheep on the low intake (0.6M) had significant reductions in FSR, protein content (g), protein synthesis (g/d) in the skin, and wool growth (g/d). The heavy lambs had similar FSR to the light lambs, but had a higher skin protein content and total protein synthesis per unit of skin area (100 cm2) and, therefore, grew more wool. The rapeseed-meal diet increased FSR and wool growth only in the light lambs over the short term. The protein deposited in wool over period 1 was 0.185 of the total protein synthesis in the skin, regardless of live weight, intake or diet, a result similar to other breeds. With the changes in dietary intake, protein synthesis in the skin and muscle responded differentially, with nutrient partitioning at sub-maintenance in favour of wool growth but at supra-maintenance, following a nutrient restriction, in favour of weight gain in young growing sheep.

Type
Animal Nutrition
Copyright
Copyright © The Nutrition Society 1998

References

Agricultural and Food Research Council Technical Committee on Responses to Nutrients (1993) Energy and Protein Requirements of Ruminants. Wallingford: CAB INTERNATIONAL.Google Scholar
Black, JL, Robards, GE & Thomas, R (1973) Effects of protein and energy intakes on the wool growth of Merino wethers. Australian Journal of Agricultural Research 24, 399412.CrossRefGoogle Scholar
Calder, AG, Anderson, SE, Grant, I, McNurlan, MA & Garlick, PJ (1992) The determination of low d5-phenylalanine enrichment (0.002–0.09 atom percent excess), after conversion to phenyl-ethylamine, in relation to protein turnover studies by gas chromatography/electron ionization mass spectrometry. Rapid Communications in Mass Spectrometry 6, 421424.CrossRefGoogle Scholar
Calder, AG & Smith, A (1988) Stable isotope ratio analysis of leucine and ketoisocaproic acid in blood plasma by gas chromatography/mass spectrometry. Use of tertiary butyl- dimethylsilyl derivatives. Rapid Communications in Mass Spectrometry 2, 1416.CrossRefGoogle Scholar
Faichney, GJ & White, GA (1983) Methods for the Analysis of Feeds Eaten by Ruminants. Blacktown: CSIRO Division of Animal Production.Google Scholar
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, 77126.CrossRefGoogle Scholar
Harris, PM, Dellow, DW & Sinclair, BR (1989) Preliminary ‘in vivo’ measurements of protein and energy metabolism in the skin of sheep. Australian Journal of Agricultural Research 40, 879888.CrossRefGoogle Scholar
Harris, PM, Lee, J, Sinclair, BR & Treloar, BP (1994 a) The effect of whole body cysteine supplementation on cysteine utilization by the skin of a well-fed sheep. Proceedings of the New Zealand Society of Animal Production 54, 139142.Google Scholar
Harris, PM, Lee, J, Sinclair, BR, Treloar, BP & Gurnsey, MP (1994 b) Effect of food intake on energy and protein metabolism in the skin of Romney sheep. British Journal of Nutrition 71, 647660.CrossRefGoogle ScholarPubMed
Harris, PM & Lobley, GE (1991) Amino acid and energy metabolism in the peripheral tissues of ruminants. In Physiological Aspects of Digestion and Metabolism in Ruminants: Proceedings of the VII International Symposium on Ruminant Physiology, pp. 201230 [Tsuda, T, Sasaki, Y and Kawashima, R, editors]. San Diego: Academic Press.CrossRefGoogle Scholar
Hill, R (1991) Rapeseed meal in the diets of ruminants. Nutrition Abstracts and Reviews B 61, 139154.Google Scholar
Langlands, JP & Wheeler, JL (1968) The dyebanding and tattooed patch procedures for estimating wool production and obtaining samples for the measurement of fibre diameter. Australian Journal of Experimental Agriculture and Animal Husbandry 8, 265269.CrossRefGoogle Scholar
Liu, SM, Lobley, GE, MacLeod, NA, Kyle, DJ, Chen, XB & Ørskov, ER (1995) Effects of long-term protein excess or deficiency on whole-body protein turnover in sheep nourished by intragastric infusion of nutrients. British Journal of Nutrition 75, 829839.CrossRefGoogle Scholar
Lobley, GE, Harris, PM, Skene, PA, Brown, D, Milne, E, Calder, AG, Anderson, SE, Garlick, PJ, Nevison, I & Connell, A (1992) Responses in tissue synthesis to sub- and supra-maintenance intake in young growing sheep: comparison of large-dose and continuous-infusion techniques. British Journal of Nutrition 68, 373388.CrossRefGoogle ScholarPubMed
MacRae, JC, Walker, A, Brown, D & Lobley, GE (1993) Accretion of total protein and individual amino acid by organs and tissues of growing lambs and the ability of nitrogen balance techniques to quantitate protein retention. Animal Production 57, 237245.Google Scholar
Masters, DG, Mata, G, Liu, SM & Peterson, AD (1998) The influence of live weight, live-weight change and diet on wool growth, staple strength and fibre diameter in young sheep. Australian Journal of Agricultural Research 49, 269277.CrossRefGoogle Scholar
Nash, JE, Rocha, HJG, Buchan, V, Calder, GA, Milne, E, Quirke, JF & Lobley, GE (1994) The effect of acute and chronic administration of the β-agonist, cimaterol, on protein synthesis in ovine skin and muscle. British Journal of Nutrition 71, 501514.CrossRefGoogle ScholarPubMed
Peter, DW, Doyle, PT & Curtis, KMS (1993) Supplements for weaners. In Management for Wool Quality in Mediterranean Environments, pp. 132141 [Doyle, PT, Fortune, JA and Adams, NR, editors]. Perth: Department of Agriculture.Google Scholar
Reis, PJ, Tunks, DA & Munro, SG (1990) Effects of the infusion of amino acids into the abomasum of sheep, with emphasis on the relative value of methionine, cysteine and homocysteine for wool growth. Journal of Agricultural Science, Cambridge 114, 5968.CrossRefGoogle Scholar
Reis, PJ, Tunks, DA & Munro, SG (1992) Effects of abomasal protein and energy supply on wool growth in Merino sheep. Australian Journal of Agricultural Reserch 43, 13531366.CrossRefGoogle Scholar
Slater, C, Preston, T, McMillan, DC, Falconer, JS & Fearon, KCH (1995) GC/MS analysis of [2H5]phenylalanine at very low enrichment: measurement of protein synthesis in health and disease. Journal of Mass Spectrometry 30, 13251332.CrossRefGoogle Scholar
Stewart, AM, Moir, RJ & Schinckel, PG (1961) Seasonal fluctuations in wool growth in south Western Australia. Australian Journal of Experimental Agriculture and Animal Husbandry 1, 8591.CrossRefGoogle Scholar
Rocha, HJG, Nash, JA, Connell, A & Lobley, GE (1993) Protein synthesis in ovine muscle and skin: sequential measurements with three different amino acids based on the large-dose procedures. Comparative Biochemistry and Physiology 105B, 301307.Google Scholar
Wilkinson, L, Hill, M, Welna, JP & Birkenbeuel, GK (1992) Systat for Windows: Statistics, version 5 edition. Evanston: Systat Inc.Google Scholar