Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-10-28T08:38:56.531Z Has data issue: false hasContentIssue false
  • English
  • Français

Selection for improved food conversion ratio on ad libitum group feeding in pigs

Published online by Cambridge University Press:  02 September 2010

A. J. Webb  and
J. W. B. King
A. J. Webb
Affiliation:
ARC Animal Breeding Research Organisation, West Mains Road, Edinburgh EH9 3JQ
J. W. B. King
Affiliation:
ARC Animal Breeding Research Organisation, West Mains Road, Edinburgh EH9 3JQ
Get access

Abstract

An experiment was conducted to show the effectiveness of selection for improved food conversion ratio on ad libitum group feeding. Selection (32 ♀♀ and 8 ♂♂) and unselected control (32 ♀♀ and 16 ♂♂ lines were maintained for seven generations at the rate of one per year. Progeny were fed ad libitum from 27 to 82 kg live weight: boars singly or in pairs, and gilts in litter groups. Selection was on pen average food conversion ratio (food/live-weight gain), recalculated as each pig reached 82 kg.

In spite of selection differentials averaging 0·61 s.d. per generation, there was no response (selection minus control) in food conversion at Generation 6 (−0·03, s.e. 0·08). However, there were correlated increases in daily live-weight gain (56, s.e. 18 g), daily food intake (145, s.e. 59 g) and ultrasonic backfat (2·4, s.e. 0·4 mm). In Generation 7, 146 full-sib pairs (male castrate and gilt) were tested on ad libitum or scale (0·77 g/g ad libitum daily food intake) feeding. Line by feeding regime interactions were absent for all traits except killing-out proportion and belly thickness.

The increased fatness of the selection line on ad libitum feeding was retained on the scale (2·2 v. 2·4, s.e. 10 mm), suggesting a primary difference in partition of nutrients rather than intake. The selection procedure adopted was not successful in improving food conversion, but no clear conclusions could be drawn from the experiment. Uncertainty remains as to the value of group food consumption measurements in selection programmes.

Type
Research Article
Information
Animal Production , Volume 37 , Issue 3 , December 1983 , pp. 375 - 385
Copyright
Copyright © British Society of Animal Science 1983

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

REFERENCES

Berger, P. J. and Harvey, W. R. 1975. Realized genetic parameters from index selection in mice. J. Amm. Sci. 40: 38–47.Google ScholarPubMed
Bernard, C. and Fahmy, M. H. 1970. Effect of selection on feed utilization and carcass score in swine. Can. J. Anim. Sci. 50: 575–584.CrossRefGoogle Scholar
Cuthbertson, A. 1968. PIDA dissection techniques. Proc. Svmp. Melh. Carcass Evaluation, Eur. Ass. Anim. Prod.. Dublin.Google Scholar
Dickerson, G. E. and Grimes, J. C. 1947. Effectiveness of selection for efficiency of gain in Duroc swine. J. Amm. Sci. 6: 265–287.Google ScholarPubMed
Ellis, M., Smith, W. C. and Laird, R. 1979. Correlated responses in feed intake to selection for economy of production and carcass lean content in Large White pigs. Anim. Prod. 28: 424 (Abstr.).Google Scholar
Fowler, V. R., Bichard, M. and Pease, A. 1976. Objectives in pig breeding. Anim. Prod. 23: 365–387.Google Scholar
Fredeen, H. T. 1972. Factors influencing genetic gain. In Pig Production (ed. Cole, D. J. A.), pp. 3–19. Butterworth. London.Google Scholar
Fredeen, H. T. 1980. Pig breeding: current programs vs. future production requirements. Can. J. Anim. Sci. 60: 241–251.CrossRefGoogle Scholar
Harvey, W. R. 1977. Users guide for LSML76. Mixed model least-squares and maximum likelihood computer program. The Ohio State Univ.. Columbus. (Mimeograph).Google Scholar
Hill, W. G. 1972. Estimation of realized heritabilities from selection experiments. II. Selection in one direction. Biometrics 28: 767–780.CrossRefGoogle Scholar
Hill, W. G. 1980. Design of quantitative genetic selection experiments. In Selection Experiments in Laboratory and Domestic Animals (ed. Robertson, A.). pp. 1–13. Commonwealth Agricultural Bureaux. Slough.Google Scholar
Jungst, S. B., Christian, L. L. and Kuhlers, D. L. 1981. Response to selection for feed efficiency in individually fed Yorkshire boars. J. Anim. Sci. 53: 323–331.CrossRefGoogle Scholar
McPhee, C. P. 1981. Selection for efficient lean growth in a pig herd. Aust. J. agric. Res. 32: 681–690.CrossRefGoogle Scholar
Pedersen, O. K. 1979. Testing of breeding animals for meat production and meat quality in Denmark. In Muscle Function and Porcine Meat Quality (ed. Wegger, I.., Hyldgaard-Jensen, J.. Moustgaard, J. and Andersen, J. E.). Proc. NJF Svmp., Denmark. Ada Agric. scand., Suppl. 21, pp. 122–135.Google Scholar
Sather, A. P. and Fredeen, H. T. 1978. Effect of selection for lean growth rate upon feed utilization by the market hog. Can. J. Anim. Sci. 58: 285–289.CrossRefGoogle Scholar
Smith, C. and Ross, G. J. S. 1965. Genetic parameters of British Landrace bacon pigs. Anim. Prod. 7: 291–301.Google Scholar
Vangen, O. 1980. Studies on a two trait selection experiment in pigs. III. Correlated responses in daily feed intake, feed conversion and carcass traits. Ada Agric. scand. 30: 125–141.CrossRefGoogle Scholar
Webb, A. J. 1975. A note on the repeatability of ultrasonic backfat measurements in pigs. Anim. Prod. 20: 433–436.CrossRefGoogle Scholar
Webb, A. J. and King, J. W. B. 1976. Development of a synthetic pig sire line by selection with immigration. 1. Results of selection and heritability estimates. Anim. Prod. 22: 231–244.Google Scholar
Wyllie, D., Morton, J. R. and Owen, J. B. 1979. Genetic aspects of voluntary food intake in the pig and their association with gain and food conversion efficiency. Anim. Prod. 28: 381–390.Google Scholar