Hostname: page-component-848d4c4894-ttngx Total loading time: 0 Render date: 2024-05-24T05:00:22.728Z Has data issue: false hasContentIssue false

The influence of abomasal supplements of zein and some amino acids on wool growth rate and plasma amino acids

Published online by Cambridge University Press:  27 March 2009

P. J. Reis
Affiliation:
C.S.I.R.O., Division of Animal Physiology, Ian Clunies Ross Animal Research Laboratory, P.O. Box 239, Blacktown, N.S.W. 2148, Australia
D. A. Tunks
Affiliation:
C.S.I.R.O., Division of Animal Physiology, Ian Clunies Ross Animal Research Laboratory, P.O. Box 239, Blacktown, N.S.W. 2148, Australia

Summary

Merino sheep were given abomasal infusions of (i) zein (80 g/day), (ii) zein (80 g/day) supplemented with L-lysine (6 g/day), L-tryptophan (1 g/day) or lysine and tryptophan together, or (iii) L-leucine (20 g/day). Effects on wool growth (length growth rate, fibre diameter, fibre volume growth rate and mass of wool grown) and on plasma amino acids were measured.

Zein increased length growth rate and decreased fibre diameter; on average the volume growth rate and mass of wool grown were not significantly altered. The addition of tryptophan to the infusion of zein did not significantly alter wool growth, whereas the addition of lysine significantly increased all aspects of wool growth. The responses to these treatments were rapid and were adequately assessed during 12-day infusion periods. The infusion of leucine did not cause any appreciable changes in wool growth.

Leucine supplementation increased the concentration of leucine in blood plasma about six-fold. Zein decreased the concentration of lysine and ornithine in plasma and increased the concentration of several essential amino acids; leucine was increased about seven-fold. The addition of tryptophan to zein had no effects on plasma amino acids, whereas lysine decreased the concentration of several amino acids in plasma and markedly increased lysine.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1976

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

Bergen, W. G., Henneman, H. A. & Magee, W. T. (1973). Effect of dietary protein level and protein source on plasma and tissue free amino acids in growing sheep. Journal of Nutrition 103, 575–85.CrossRefGoogle ScholarPubMed
Block, R. J. & Bolling, D. (1951). The amino acid composition of proteins and foods. 2nd edn.Spring-field, Illinois: C. C. Thomas.Google Scholar
Block, R. J. & Mitchell, H. H. (1946). The correlation of the amino acid composition of proteins with their nutritive value. Nutrition Abstracts and Reviews 16, 249–78.Google Scholar
Brookes, I. M., Owens, F. N., Brown, R. E. & Garrigus, U. S. (1973). Amino acid oxidation and plasma amino acid levels in sheep with abomasal infusions of graded amounts of lysine. Journal of Animal Science 36, 965–70.CrossRefGoogle ScholarPubMed
Colebrook, W. F. & Reis, P. J. (1969). Relative value for wool growth and nitrogen retention of several proteins administered as abomasal supplements to sheep. Australian Journal of Biological Sciences 22, 1507–16.Google Scholar
Dove, H. & Robards, G. E. (1974). Effect of abomasal infusions of methionine, casein, and starch plus methionine on the wool production of Merino wethers fed on lucerne or wheaten chaff. Australian Journal of Agricultural Research 25, 945–56.Google Scholar
Downes, A. M., Clarke, W. H. & Dagg, T. C. (1967). Use of radioisotopes in the measurement of wool growth. Atomic Energy in Australia 10, 27.Google Scholar
Downes, A. M., Reis, P. J., Sharry, L. F. & Tunks, D. A. (1970). Metabolic fate of parenterally administered sulphur-containing amino acids in Sheep and effects on growth and composition of wool. Australian Journal of Biological Sciences 23, 1077–88.Google Scholar
Downes, A. M. & Sharry, L. F. (1971). Measurement of wool growth and its response to nutritional changes. Australian Journal of Biological Sciences 24, 117–30.CrossRefGoogle ScholarPubMed
Efron, M. L. (1966). Quantitative estimation of ammo acids in physiological fluids using a Technicon amino acid analyzer. In Automation in Analytical Chemistry (Technicon Symposia, 1965), pp. 637–42. New York: Mediad Inc.Google Scholar
Fenderson, C. L. & Bergen, W. G. (1972). Effect of ration composition and protein level on plasma free tryptophan and ruminal microbial tryptophan content in sheep. Journal of Animal Science 35, 896900.CrossRefGoogle ScholarPubMed
Hogan, J. P., Weston, R. H. & Lindsay, J. R. (1968). Influence of protein digestion on plasma amino acid levels in sheep. Australian Journal of Biological Sciences 21, 1263–75.CrossRefGoogle ScholarPubMed
Hume, I. D., Jacobson, D. R. & Mitchell, G. E. Jr (1972). Quantitative studies on amino acid absorption in sheep. Journal of Nutrition 102, 495505.Google Scholar
Reis, P. J. (1967). The growth and composition of wool. IV. The differential response of growth and of sulphur content of wool to the level of sulphur-containing amino acids given per abomasum. Australian Journal of Biological Sciences 20, 809–25.CrossRefGoogle Scholar
Reis, P. J. (1969). The growth and composition of wool. V. Stimulation of wool growth by the abomasal administration of varying amounts of casein. Australian Journal of Biological Sciences 22, 745–59.Google Scholar
Reis, P. J. (1970). The influence of abomasal supplements of some amino acids and sulphur-containing compounds on wool growth rate. Australian Journal of Biological Sciences 23, 441–6.CrossRefGoogle Scholar
Reis, P. J. & Colebrook, W. F. (1972). The utilization of abomasal supplements of proteins and amino acids by sheep with special reference to wool growth. Australian Journal of Biological Sciences 25, 1057–71.CrossRefGoogle ScholarPubMed
Reis, P. J. & Downes, A. M. (1971). The rate of response of wool growth to abomasal supplements of casein. Journal of Agricultural Science 76, 173–6.Google Scholar
Reis, P. J., Tunks, D. A. & Downes, A. M. (1973). The influence of abomasal and intravenous supplements of sulphur-containing amino acids on wool growth rate. Australian Journal of Biological Sciences 26, 249–58.Google Scholar
Scott, R. A., Streeter, C. L., Little, C. O. & Mitchell, G. E. Jr (1969). Oral and abomasal administration of lysine to wethers. Journal of Animal Science 28, 138.Google Scholar
Spector, W. S. (Ed.) (1956). Handbook of biological data, p. 90. Philadelphia: W. B. Saunders Co.Google Scholar
Wakeling, A. E., Lewis, D. & Annison, E. F. (1970). The amino acid requirements of ruminants. Proceedings of the Nutrition Society 29, 60A61A.Google Scholar