Hostname: page-component-586b7cd67f-2plfb Total loading time: 0 Render date: 2024-11-20T10:39:02.590Z Has data issue: false hasContentIssue false
  • English
  • Français

Effects of breed and family on rate of copper accretion in the liver of purebred Charollais, Suffolk and Texel lambs

Published online by Cambridge University Press:  18 August 2016

N. F. Suttle ,
R. M. Lewis  and
J. N. W. Small
N. F. Suttle*
Affiliation:
Moredun Research Institute, Pentland Science Park, Penicuik EH26 0PZ, UK
R. M. Lewis
Affiliation:
Animal Biology Division, Scottish Agricultural College, West Mains Road, Edinburgh EH9 3JG, UK
J. N. W. Small
Affiliation:
Moredun Research Institute, Pentland Science Park, Penicuik EH26 0PZ, UK
*
E-mail:[email protected]
Get access

Abstract

The feeding of housed lambs on conserved forages and pelleted rations is accompanied by a high risk of chronic copper (Cu) poisoning (CCP) which might be reduced by selecting sires for low liver Cu status. Livers were therefore retrieved from Suffolk, Texel and Charollais lambs, slaughtered during the course of a performance trial, to ascertain sire and possibly breed effects on the rate of Cu accretion in the liver. In total, 160 livers were obtained, 100 from Suffolk, 40 from Texel and 20 from Charollais lambs, the progeny of 14, eight and eight sires, respectively. Lambs came from three separately managed flocks but were brought together at 8 weeks of age, weaned onto a common complete diet containing 6·1 mg Cu per kg dry matter (DM) and offered ad libitum. One-fifth of each breed group was slaughtered at 14, 18 or 22 weeks and the remaining 40% at 26 weeks of age. Mean (s.e. ) liver Cu concentrations at those ages were 3220 (450), 4639 (464), 6426 (468), and 6513 (370) µmol/kg DM for Suffolk, and 5843 (811), 6579 (857), 8017 (811) and 10406 (589) µmol/kg DM for Texel, respectively. The pattern of liver Cu accretion differed, the Suffolk starting at a low value yet reaching a plateau at about 22 weeks of age (significant quadratic regression coefficient), the Texel, continually increasing from a high initial value at an average rate of 53·7 (s.e.10·6) µmol/kg DM per day. There was a significant effect of sire on liver Cu in the Suffolk (P 0·05) with a heritability of 0·85 (s.e. 0·44); in the Suffolk and Texel combined, the heritability was 0·60 (s.e. 0·33). The data available on the Charollais were too limited to test for sire effects but at 26 weeks of age, where most information was available, the mean liver Cu concentration was 7285 (s.e.826) µmol/kg DM. At a given age, food intake, liver weight and live weight were each lowest in the Texel but when expressed as a proportion of live weight (LW), both food intake (43 g/kg LW) and liver weight (5·15 g DM per kg LW) were similar among breeds (P 0·05). Thus, differences in liver Cu accretion are unlikely to reflect differences in Cu intake per unit liver weight. There was a tendency for liver size per kg LW to decrease as liver Cu rose in the Texel but not in the Suffolk. Continued hepatic Cu accretion in the Texel may reflect a breed-specific inability to cope with Cu overload. Increases in liver Cu to marginally toxic levels in some Suffolk, some Charollais and most Texel lambs, and to a level commonly associated with toxicity in one Texel lamb, on a ration of moderate Cu concentration highlights the difficulty of controlling risk of CCP by manipulating dietary composition. The current EC limit for Cu in ovine diets, 17 mg Cu per kg DM, is clearly too high for the breeds and dietary conditions used in this study. However a safe limit would be hard to achieve and hence the need to exploit sire variation in propensity to accumulate liver Cu to reduce disease risk.

Keywords

breed differencescoppersheeptoxicity
Type
Research Article
Information
Animal Science , Volume 75 , Issue 2 , October 2002 , pp. 295 - 302
Copyright
Copyright © British Society of Animal Science 2002

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Berg, R.van der, Levels, F. H. R. and Schee, W.van der. 1983. Breed differences in sheep with respect to the accumulation of copper in the liver. The Veterinary Quarterly 5: 26–31.CrossRefGoogle Scholar
Genstat 5 Committee. 1998. Genstat 5 release 4•1 (PC/ Windows NT). Lawes Agricultural Trust, Rothamsted Experimental Station, Harpenden, UK.Google Scholar
Judson, G. J., Walkley, J. R. W., James, P. J., Kleeman, D. O. and Ponzoni, R. W. 1994. Genetic variation in trace element status of Merino sheep. Proceedings of the Australian Society of Animal Production 20: 438.Google Scholar
King, T. P. and Bremner, I. 1979. Autophagy and apoptosis in liver during the pre-haemolytic phase of chronic copper poisoning in sheep. Journal of Comparative Pathology 89: 515–530.Google Scholar
Littledike, E. T. and Young, L. D. 1993. Effect of sire and dam breed on copper status of fat lambs. Journal of Animal Science 71: 774–778.Google Scholar
Luke, F. and Marquering, B. 1972. Studies on the mineral content of the sheep liver. Zuchtungskunde 44: 56–60.Google Scholar
Thomas, P. C., Robertson, S., Chamberlain, D. G., Livingstone, R. M., Garthwaite, P. H., Dewey, P. J. S., Smart, R. and Whyte, C. 1988. Predicting the metabolizable energy (ME) content of compound feeds for ruminants. In Recent advances in animal nutrition (ed. W. Haresign and D. Cole, J. A.), pp. 127–146. Butterworths, London.Google Scholar
Thompson, R. H. and Blanchflower, W. J. 1971. Wet-ashing apparatus to prepare biological materials for atomic absorption spectrophotometry Laboratory Practice 20: 859–861.Google ScholarPubMed
Underwood, E. J. and Suttle, N. F. 1999. Copper. In The mineral nutrition of livestock, third edition. CAB International, Wallingford, UK.Google Scholar
Visscher, A. H., Garssen, G. J. and Zaalmink, W. 1980. Relationship between concentrates fed and the copper concentration in liver dry matter in five sheep genotypes. Proceedings of the 31st meeting of the European Association for Animal Production, Munich, paper NS 4•4.Google Scholar
Wiener, G. 1966. Genetic and other factors in the occurrence of swayback in sheep. Journal of Comparative Pathology 76: 435–447.Google Scholar
Wiener, G. 1987. The genetics of copper metabolism in animals and man. In Copper in animals and man (ed. McC. Howell, J. and Gawthorne, J. M.), pp. 45–62. CRC Press Inc., Boca Raton, Florida.Google Scholar
Wiener, G. and Macleod, N. S. W. 1970. Breed, bodyweight and age as factors in the mortality rate of sheep following copper injection. Veterinary Record 86: 740–743.CrossRefGoogle ScholarPubMed
Wiener, G., Suttle, N. F., Field, A. C., Herbert, J. G. and Woolliams, J. A. 1978. Breed differences in copper metabolism. Journal of Agricultural Science, Cambridge 91: 433–441.Google Scholar
Woolliams, C., Suttle, N. F., Woolliams, J. A., Jones, D. G. and Wiener, G. 1986. Studies on lambs from lines genetically selected for low and high copper status. 1. Differences in mortality. Animal Production 43: 293–301.Google Scholar
Woolliams, J. A., Suttle, N. F., Wiener, G., Field, A. C. and Woolliams, C. 1982. The effect of breed of sire on the accumulation of copper in lambs, with particular reference to copper toxicity. Animal Production 35: 299–307.Google Scholar
Woolliams, J. A., Suttle, N. F., Wiener, G., Field, A. C. and Woolliams, C. 1983. The long-term accumulation and depletion of copper in the liver of different breeds of sheep fed diets of differing copper content. Journal of Agricultural Science, Cambridge 100: 441–449.Google Scholar
Woolliams, J. A., Wiener, G., Woolliams, C. and Suttle, N. F. 1985. Retention of copper in the liver of sheep genetically selected for high and low concentrations of copper in plasma. Animal Production 41: 219–226.Google Scholar
Woolliams, J. A., Woolliams, C., Suttle, N. F., Jones, D. G. and Wiener, G. 1986. Studies on lambs from lines genetically selected for low and high copper status. 2. Incidence of hypocuprosis on improved hill pasture. Animal Production 43: 303–317.Google Scholar
Young, M. J., Lewis, R. M., McLean, K. A., Robson, N. A. A., Fraser, J., FitzSimons, J., Donbavand, J. and Simm, G. 1999. Prediction of carcass composition in meat breeds of sheep using computer tomography. Proceedings of the British Society of Animal Science, 1999, p. 43.Google Scholar