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The effect of rate of gain during the growing and finishing periods on the feed efficiency and carcass composition of the pig: I. Rate of gain during the growing period from 18 to 57 kg live weight

Published online by Cambridge University Press:  27 March 2009

N. Walker
Affiliation:
Agricultural Research Institute of Northern Ireland, Hillsborough and Queen's University, Belfast
D. W. Holme
Affiliation:
Agricultural Research Institute of Northern Ireland, Hillsborough and Queen's University, Belfast
T. J. Forbes
Affiliation:
Agricultural Research Institute of Northern Ireland, Hillsborough and Queen's University, Belfast

Summary

Two experiments were carried out in which pigs were grown at controlled high, moderate or low growth rates from 18 kg to slaughter at 57 kg live weight. Linear measurements and density determinations were carried out on the carcasses. In the second experiment the right-hand side of each carcass was divided into four joints and each joint was physically dissected into three components, bone, subcutaneous fat plus skin and ‘lean’ meat. The boneless tissue of each joint was analysed for moisture, ether extractable fat and nitrogen.

It was found that an increase in the rate of live-weight gain tended to improve the efficiency with which feed was converted into live weight.

The percentage of fat in the side was significantly increased by more rapid growth rates.

The conformation of the side was altered by treatment, the proportion by weight of the middle region increased with increasing rate of live-weight gain and was accompanied by corresponding reductions in the proportions of the gammon and shoulder regions. These changes were largely due to an effect on the distribution of fat throughout the side, but there were also minor changes in the distributions of bone and fat-free lean.

The high rate of gain was associated with a greater proportion of belly in the side. This was due to an increase in the proportion of lean meat in this region, presumably a functional effect caused by an increased intestinal volume.

There was no treatment effect on the chemical composition of the fat-free boneless meat which was found to differ significantly between joints.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1968

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References

REFERENCES

Baur, L. S. & Filer, L. J. Jr (1959). Influence of body composition of weanling pigs on survival under stress. J. Nutr. 69, 128–34.CrossRefGoogle ScholarPubMed
Becker, D. E. (1963). Reported in Journal, 02 1963, Trouw and Co., Spinozastraat 1, Amsterdam—C.Google Scholar
Buck, S. F. (1963 a). A comparison of pigs slaughtered at three different weights. I. Carcass quality and performance. J. agric. Sci., Camb. 60, 1926.CrossRefGoogle Scholar
Buck, S. F. (1963 b). A comparison of pigs slaughtered at three different weights. II. Association between dissection results, various measurements and visual assessements. J. agric. Sci., Camb. 60, 27–9.CrossRefGoogle Scholar
Clausen, H. (1953). The improvement of pigs. The George Scott Robertson Memorial Lecture for 1953, Belfast, Marjory Boyd, M.A.Google Scholar
Coey, W. E. (1954). The relationship between growth rate and carcass conformation in pigs. Agric. Progr. 29, 60–5.Google Scholar
Coey, W. E. (1957). Factors affecting the carcass conformation of bacon pigs. Ph.D. Thesis, The Queen's University of Belfast.Google Scholar
Cray, A. S. (1955). Recent experiences of pig production. J. Frs' Club, Lond. 3, 3343.Google Scholar
Elsley, F. W. H. (1963). Studies on growth and development in the young pig. I. The carcass composition at 56 days of age of pigs reared along different growth curves. J. agric. Sci., Camb. 61, 233–42.CrossRefGoogle Scholar
Elsley, F. W. H., McDonald, I. & Fowler, V. R. (1964). The effect of plane of nutrition on the carcasses of pigs and lambs when variations in fat content are excluded. Anim. Prod. 6, 141–54.Google Scholar
Hammond, J. (1932). Pigs for pork and pigs for bacon, general considerations. Jl R. agric. Soc. Engl. 93, 131–45.Google Scholar
Hill, F. & O'Carroll, F. M. (1962). The chemical composition of pig carcasses at pork, bacon and manufacturing weights. Irish J. agric. Res. 1, 115–30.Google Scholar
Lawrie, R. A. (1961). Studies on the muscles of meat animals. I. Differences in composition of beef longissimus dorsi muscles determined by age and anatomical location. J. agric. Sci., Camb. 56, 249–59.CrossRefGoogle Scholar
Lawrie, R. A., Pomeroy, R. W. & Cuthbertson, A. (1963). Studies on the muscles of meat animals. III. Comparative composition of various muscles in pigs of three weight groups. J. agric. Sci., Camb. 60. 195209.CrossRefGoogle Scholar
Loane, D. J. (1966). A study of various factors affecting carcass quality in the pig. Ph.D. Thesis, The Queen's University of Belfast.Google Scholar
Lucas, I. A. M., McDonald, I. & Calder, A. F. C. (1960). Some further observations upon the effects of varying the plane of feeding for pigs between weaning and bacon weight. J. agric. Sci., Camb. 54, 8199.CrossRefGoogle Scholar
McMeekan, C. P. (1940 a). Growth and development in the pig, with special reference to carcass quality characters. I. J. agric. Sci., Camb. 30, 276343.CrossRefGoogle Scholar
McMeekan, C. P. (1940 b). Growth and development in the pig with special reference to carcass quality characters. II. The influence of the plane of nutrition on growth and development. J. agric. Sci., Camb. 30, 387436.CrossRefGoogle Scholar
McMeekan, C. P. (1940 c). Growth and development in the pig with special reference to carcass quality characters. III. Effect of the plane of nutrition on the form and composition of the bacon pig. J. agric. Sci., Camb. 30, 511–69.CrossRefGoogle Scholar
Neilsen, H. E. (1964). Growth rate of piglets as related to their later performance. Annis Zootech. 13, Special no. 1, 169–75.Google Scholar
Oslage, H. J. (1962). Body composition and accretion of matter by growing fattening pigs and the influence of nutrition. 2. Body composition and accretion by growing fattening pigs in conditions of normal nutrition. Z. Tierphysiol Tierernäh. Futtermittelk. 17, 357–82.CrossRefGoogle Scholar
Palsson, H. (1955). Conformation and body composition. In Progress in the Physiology of Farm Animals, vol. II. London: Butterworths.Google Scholar
Snedecor, G. W. (1956). Statistical Methods. Ames: Iowa State College Press.Google Scholar
Speer, V. C. (1964). Restricted feeding of hogs. Proc. 1964 Maryland Nutrition Conference, p. 37. University of Maryland.Google Scholar
Steel, R. G. D. & Torrie, J. H. (1960). Principles and Procedures of Statistics. New York: McGraw-Hill.Google Scholar