Hostname: page-component-78c5997874-4rdpn Total loading time: 0 Render date: 2024-11-19T16:21:51.672Z Has data issue: false hasContentIssue false

Hexoestrol implantation of steers fattened at pasture I. Effects on growth and herbage intake

Published online by Cambridge University Press:  02 September 2010

F. E. Alder
Affiliation:
The Grassland Research Institute, Hurley, Berkshire
J. C. Tayler
Affiliation:
The Grassland Research Institute, Hurley, Berkshire
J. E. Rudman
Affiliation:
The Grassland Research Institute, Hurley, Berkshire
Get access

Extract

The possibility of using hormones to increase the productivity of meat animals has been considered for a number of years (Hammond, 1957 and Scarisbrick, 1960). Lamming (1957) has pointed out that most of the work with hormones and beef cattle has been done in the U.S.A. under feedlot conditions. In this country Aitken and Crichton (1956), Dodsworth (1957) and Lamming (1957 and 1958) all obtained increases in rates of gain with implantation. Lamming found that responses in steers varied from 0 to 15% increase in gain per day in spring, about 20% in summer, 40% in autumn, i n each case on pasture and up to 60% under winter feeding conditions. He also used several levels of implantation, from which it appeared that the optimum level was about 45 mg. hexoestrol. Smith (1958) described trials conducted at eight farms in the North of Scotland in which 189 steers fattened solely on grass were implanted with hexoestrol. Implantation resulted in an extra daily live-weight gain of about 0·5 lb. Increases in dose levels above 60 mg. produced no significant response in terms of live-weight gain. Eighteen experiments at Experimental Husbandry Farms and the Norfolk Agricultural Station, described by Jones (1961), also showed that live-weight gain was increased by implanting; that the correct dose to give maximum response appeared to be 45 to 60 mg. hexoestrol; and that the implant should be made from 100 to 130 days before slaughter. Second implantations were made in several of these experiments and it appeared doubtful if this practice was desirable. In New Zealand, Lucas (1958) and Everitt (1959) also found that hexoestrol implantation increased weight gains of grazing steers.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1964

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

Aitken, J. N. & Crichton, J. A., 1956. The effect of hexoestrol implantation on growth and certain characteristics of fattening steers. Brit. J. Nutr., 10: 220.CrossRefGoogle ScholarPubMed
Alder, F. E., 1958a. The overwintering of young cattle. Proc. Brit. Soc Anim. Prod., 1958: p. 53.Google Scholar
Alder, F. E., 1958b. Winter grazing study. Exp. Prog. Grassl. Res. Inst. Hurley, 10: 31.Google Scholar
Dodsworth, T. L., 1957. The use of hexoestrol in beef production. Agric. Rev. (Lond.), 2(II): 23.Google Scholar
Everitt, G. C., 1959. Further studies with hexoestrol for beef production. Proc. Ruakura Fmrs' Conf., p. 25.Google Scholar
Grassland Research Institute, 1961. Techniques in use at the Grassland Research Institute. Bull. Commonw. Bur. Past. Fid Crops., no. 45.Google Scholar
Hammond, J., 1957. Hormones in meat production. Outlook on Agric., 1: 230.CrossRefGoogle Scholar
Harkess, R. D., 1963. Studies in herbage digestibility. J. Brit. Grassl. Soc., 18: 62.CrossRefGoogle Scholar
Jones, P. J., 1961. Implantation of cattle for beef with hexoestrol. Exp. Husb., 6: 62.Google Scholar
Lamming, G. E., 1957. The use of hormones in meat production. Agric. Progr., 32: 1.Google Scholar
Lamming, G. E., 1958. Recent developments in the use of growth stimulants in farm animals. J. Roy. Agric. Soc., 119: 41.Google Scholar
Lucas, I. A. M., 1958. Hormone implants in beef production. Proc. Ruakura Fmrs' Conf., p. 110.Google Scholar
Minson, D. J., Tayler, J. C., Alder, F. E., Raymond, W. F., Rudman, J. E., Line, C. & Head, M. J., 1960. A method for identifying the faeces produced by individual cattle or groups of cattle grazing together. J. Brit. Grassl. Soc., 15: 86.CrossRefGoogle Scholar
National Research Council, U.S.A., Comm. Anim. Nutrition, 1950. Recommended nutrient allowances for domestic animals, No. 4, Washington, D.C.: Nat. Res. Council.Google Scholar
Preston, T. R., Rochanasaroj, V. & Gee, Isoline, 1958. The effect of hexoestrol on nitrogen retention of lambs and on ration digestibility. Proc. Brit. Soc. Anim. Prod., 1958, p. 13.Google Scholar
Roy, J. H. B., 1959. Calves (Dairy and Beef) in Proceedings of a conference on the scientific principles of feeding farm animals. Farmer & Stockbreeder Publications, London.Google Scholar
Scarisbrick, R., 1960. The problems arising from the use of feedingstuffs additives J. Fmrs' Cl. Lond. (1).Google Scholar
Smith, R. G. C., 1958. Hexoestrol—grazing cattle. Agric. Rev. (Lond.), 3 (9): 29.Google Scholar
Tilley, J. M. A., Deriaz, R. C. & Terry, R. A., 1960. The in vitro measurement of herbage digestibility and assessment of nutritive value. Proc. 8th int. Grassl. Congr. (.Reading), p. 333.Google Scholar
Wallace, L. R., 1956. The intake and utilisation of pasture by grazing dairy cattle. Proc. 1th int. Grassl. Congr. (New Zealand), p. 134.Google Scholar