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Backfat studies in growing pigs 1. Influence of energy intake on growth and carcass measurements at varying live weights

Published online by Cambridge University Press:  02 September 2010

L. R. Giles
Affiliation:
Department of Agriculture, Agricultural Research Centre, Wollongbar, New South Wales 2480, Australia
R. D. Murison
Affiliation:
Department of Agriculture, Agricultural Research Centre, Wollongbar, New South Wales 2480, Australia
B. R. Wilson
Affiliation:
Department of Agriculture, Agricultural Research Centre, Wollongbar, New South Wales 2480, Australia
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Abstract

1. Measurements of digestible energy intake, live growth and carcass measurements were conducted with 96 individually housed pigs (48 male and 48 female) given the same diet at four feeding levels (ad libitum; Agricultural Research Council daily digestible energy intake (C); C–12·5%; and C–25% daily digestible energy intake. The pigs were slaughtered at one of six live weights (45, 60, 75, 90, 105, 120 kg).

2. Prediction equations of average daily live-weight gain and introscope P2 backfat thickness on the hot carcass (hot P2) were developed as functions of average daily digestible energy intake for males and females at varying live weights. The relationships found were 20·8 g live-weight gain per MJ digestible energy intake and 0·81 mm hot P2 backfat thickness per MJ digestible energy intake from 25 to 90 kg live weight.

3. Compared with feeding level C, C –25% produced no difference in feed conversion ratio, reduced shoulder maximum, mid-back and loin minimum backfat thickness by 6–8 mm (14–4%), 4–2 mm (168%) and 4–1 mm (17–5%) respectively (P<0·01) and increased eye-muscle area by 2908mm2 (10·9%).

4. Compared with females, males reached slaughter weight 9·4 days earlier, increased daily live-weight gain by 64g, increased feed conversion ratio by 0·3, had 1·6mm less hot P2 backfat thickness, had less backfat at all mid-line positions and showed no difference in eye-muscle area.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1981

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References

REFERENCES

Agricultural Research Council. 1967. The Nutrient Requirements of Farm Livestock. No. 3, Pigs. Agricultural Research Council, London.Google Scholar
Barber, R. S., Braude, R., Mitchell, K. G. and Pittman, R. J. 1972. Effect of level of feed intake on the performance and carcass composition of growing pigs. Anim. Prod. 14: 199208.Google Scholar
Buck, S. F., Harrington, G. and Johnson, R. F. 1962. The prediction of lean percentage of pigs of bacon weight from carcass measurements. Anim. Prod. 4: 2536.Google Scholar
Davies, J. L. and Lucas, I. A. M. 1972. Responses to variations in dietary energy intakes by growing pigs. 3. Effect of level of intake of diets of differing protein and fat content on the performance of growing pigs. Anim. Prod. 15: 127137.Google Scholar
Field, S. B. 1977. A pork test marketing committee, background, progress and problems. Proc. Symp. Promotion and Marketing of Pigmeats, pp. 7073. Bendigo, Victoria.Google Scholar
Harrington, G. 1972. Fat Measurement and Conformation in the Classification and Grading of British Pigs. Meat and Livestock Commission, Bletchley. (Mimeograph).Google Scholar
Holmes, C. W. 1971. Growth and backfat depth of pigs kept at a high temperature. Anim. Prod. 13: 521527.Google Scholar
Houghton, T. R., Butterworth, M. H., King, D. and Goodyear, R. 1964. The effects of different levels of food intake on fattening pigs in the humid tropics. J. agric. Sci., Camb. 63: 4350.CrossRefGoogle Scholar
Kempster, A. J. 1977. Variation and trends in the weight and fat thickness of commercial British pigs. Livest. Prod. Sci. 5: 215223.CrossRefGoogle Scholar
McMeekan, C. P. 1940. Growth and development in the pig, with special reference to carcass quality characters. I. J. agric. Sci, Camb. 30: 276343 (references 31: 24–27).CrossRefGoogle Scholar
Mount, L. E. 1968. The Climatic Physiology of the Pig, p. 232. Edward Arnold, London.Google Scholar
Pigmeat Promotion Advisory Committee. 1979. Superporker Cutting Instructions. Sydney South, New South Wales. (Mimeograph).Google Scholar