Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-05T13:24:41.749Z Has data issue: false hasContentIssue false

Effects of age and state of incisor dentition on faecal output of dry matter and on faecal and urinary output of nitrogen and minerals, of sheep grazing hill pastures

Published online by Cambridge University Press:  27 March 2009

A. C. Field
Affiliation:
Moredun Research Institute, Edinburgh, EH 17 7JH
A. R. Sykes
Affiliation:
Moredun Research Institute, Edinburgh, EH 17 7JH
R. G. Gunn
Affiliation:
Hill Farming Research Organisation, Bush Estate, Midlothian, EH26 OPH

Summary

Excretion of D.M., N, Ca, P and Mg in faeces, and N, P and Mg in urine were measured at intervals over 12 months in breeding Scottish Blackface sheep grazing hill pastures. These values were used with data on reproductive performance and body compositional changes, to calculate the energy, nitrogen and mineral balances. The sheep were: 11 6½-year-old with sound mouths (SM), 16 6½-year-old with broken mouths (BM), 16 5½-year-old with all permanent incisors clipped to gum level (CM) and 16 2½-year-old (Y). An energy supplement was given at the end of gestation and during early lactation. All faeces were collected and creatinine was used as an internal marker to estimate urine volume.

Faecal D.M. output ranged from 443 to 662 g/day, with highest values in November and lowest in May. Average values for the BM sheep were lower than those for the other groups but when output was expressed as a power function of body weight, the values for the Y sheep were 15% higher than those for the other groups. Faecal excretions of Ca and P in January and February were very low and the values for P were half the expected endogenous faecal loss.

Urinary output ofN ranged from 6·0 g/day in February to 22·2 g/day in August and the corresponding urinary urea N: total N ratios were 0·24 and 0·69. Urinary Mg output was highest in late summer and early winter but urinary P showed no consistent trends.

The estimated daily intakes of DOM (g) were 936 in November 1969, 599 in January, 414 in February, 1075 in May, 1150 in August and 946 in November 1970.

The loss of energy from the body between mating (November) and mid-lactation (June) ranged from 9·5 to 16·8% of the total calculated ME requirements in the Y and BM sheep, respectively. Maintenance requirements averaged 204 kJ/kg body weight/day and the value for the Y sheep was 12% higher than the mean for the older sheep.

Nitrogen and mineral balances were calculated for February, May, August and November. The sheep were protein-deficient in winter, not from a shortage of crude protein in the diet but because of its low digestibility (34%). Intakes of Ca and P in winter were low and a real possibility of a P deficiency exists. Estimates of the concentrations of N and of minerals in the herbage consumed by the sheep were made and compared with those obtained for cut herbage from the same pastures. It would appear that the sheep selected herbage of a higher protein content than that of the cut herbage. Herbage selection was greatest in November.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1974

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

Agricultural Research Council (1965). The Nutrient Requirements of Farm Livestock. No. 2. Ruminants. London: Agricultural Research Council.Google Scholar
Ashton, W. M. & Yousef, I. M. (1966). A study of the composition of Clun Forest ewe's milk. II. Mineral constituents. Journal of Agricultural Science, cambridge 67, 7780.CrossRefGoogle Scholar
Blaxter, K. L. (1962). The Energy Metabolism of Ruminants. London: Hutchinson.Google Scholar
Blaxter, K. L. & Rook, J. A. F. (1953). The heat of combustion of the tissues of cattle in relation to their chemical composition. British Journal of Nutrition 7, 8391.CrossRefGoogle ScholarPubMed
Braithwaite, G. D. & Riazuddin, Sh. (1971). The effect of age and level of dietary calcium intake on calcium metabolism in sheep. British Journal of Nutrition 26, 215–25.CrossRefGoogle ScholarPubMed
Coop, I. E. & Abrahamson, M. (1973). Effect of teeth condition on intako of grazing sheep. New Zealand Journal of Experimental Agriculture 1, 5864.CrossRefGoogle Scholar
Coop, I. E. & Hill, M. K. (1962). The energy requirements of sheep for maintenance and gain. II. Grazing sheep. Journal of Agricultural Science, Cambridge 58, 187–99.CrossRefGoogle Scholar
Doney, J. M. & Smith, W. F. (1961). The fleece of Scottish Blackface sheep. I. Seasonal changes in wool production and fleece structure. Journal of Agricultural Science, Cambridge 56, 365–74.CrossRefGoogle Scholar
Eadie, J. (1967). The nutrition of grazing hill sheep; utilization of hill pasture. 4th Report, Hill Farming Research Organisation, pp. 3845.Google Scholar
Field, A. C. (1967). Studies on magnesium in ruminant nutrition. 7. Excretion of magnesium, calcium, potassium and faecal dry matter by grazing sheep. British Journal of Nutrition 21, 631–42.CrossRefGoogle ScholarPubMed
Field, A. C. & Suttle, N. F. (1969). Some observations on endogenous loss of calcium in the sheep. Journal of Agricultural Science, Cambridge 73, 507–9.CrossRefGoogle Scholar
Field, A. C, Suttle, N. F. & Gunn, R. G. (1968). Seasonal changes in the composition and mineral content of the body of hill ewes. Journal of AgriculturalScience, Cambridge 71, 303–10.CrossRefGoogle Scholar
Fiske, C. A. & Subbarow, Y. (1925). The colorometric determination of phosphorus. Journal of Biological Chemistry 66, 375400.CrossRefGoogle Scholar
Graham, N. McC. (1968). Effects of undernutrition in late pregnancy on the nitrogen and energy metabolism of ewes. Australian Journal of Agricultural Research 19, 555–65.Google Scholar
Gunn, R. G. (1969). The effects of calcium and phosphorus supplementation on the performance of Scottish Blackface hill ewes, with particular reference to the premature loss of permanent incisor teeth. Journal of Agricultural Science, Cambridge 72, 371–78.CrossRefGoogle Scholar
Langlands, J. P. (1966). Creatinine as an index substance for estimating the urinary excretion of nitrogen and potassium by grazing sheep. Australian Journal of Agricultural Research 17, 757–63.CrossRefGoogle Scholar
Langlands, J. P., Corbett, J. L., MacDonald, I. & Reid, G. W. (1963). Estimates of the energy required for maintenance by adult sheep. 2. Grazing sheep. Animal Production 5, 1116.Google Scholar
Mathieson, J. (1970). The automated estimation of chromic oxide. Proceedings of the Nutrition Society 29, 30A.Google Scholar
National Research Council (1957). Nutrient Requirements of Domestic Animals No. V. Nutrient Requirements of Sheep. Publication of the National Research Council, Washington.Google Scholar
Robinson, J. J. & Forbes, T. J. (1966). A study of the protein requirements of the mature breeding ewe. Maintenance requirement of the non-pregnant ewe. British Journal of Nutrition 20, 263–72.CrossRefGoogle ScholarPubMed
Robinson, J. J. & Forbes, T. J. (1967). A study of the protein requirements of the mature breeding ewe. 2. Protein utilization in the pregnant ewe. British Journal of Nutrition 21, 879–91.CrossRefGoogle ScholarPubMed
Robinson, J. J., Scott, D. & Fraser, C. (1973). Observations on the effect of protein intake and stage of gestation on the proportion of urinary nitrogen excreted as urea in sheep. Journal of Agricultural Science, Cambridge 80, 363–68.CrossRefGoogle Scholar
Simmonds, D. M. (1954). The amino acid composition of Keratins. 1. The amino acid analysis of Merino 64's quality virgin wool. Australian Journal of Biological Science 7, 98110.CrossRefGoogle Scholar
Sykes, A. R. & Field, A. C. (1972 a). Effect of dietary deficiencies of energy, protein and calcium on the pregnant ewe. I. Body composition and mineral content of the ewes. Journal of Agricultural Science, Cambridge 78, 109–17.CrossRefGoogle Scholar
Sykes, A. R. & Field, A. C. (1972 b). Effect of dietary deficiencies of energy, protein and calcium on the pregnant ewe. III. Some observations on the use of biochemical parameters in controlling energy undernutrition during pregnancy and on the efficiency of utilization of energy and protein for foetal growth. Journal of Agricultural Science, Cambridge 78, 127–33.CrossRefGoogle Scholar
Sykes, A. R. & Field, A. C. (1974). Seasonal changes in plasma concentrations of proteins, urea, glucose, calcium and phosphorus in sheep grazing a hill pasture and their relationship to change in body composition. Journal of Agricultural Science, Cambridge 83, 161–69.CrossRefGoogle Scholar
Sykes, A. R., Field, A. C. & Gunn, R. G. (1974 a). Effects of age and state of inoisor dentition on the body composition and lamb production of sheep grazing hill pastures. Journal of Agricultural Science, Cambridge 83, 135–43.CrossRefGoogle Scholar
Sykes, A. R., Field, A. C. & Gunn, R. G. (1974 b). Effects of age and state of incisor dentition on the chemical composition of the skeleton of sheep grazing hill pastures. Journal of Agricultural Science, Cambridge 83, 145–50.CrossRefGoogle Scholar
Sykes, A. R., Nisbet, D. I. & Field, A. C. (1973). Effects of dietary deficiencies of energy, protein and calcium on the pregnant ewe. V. Chemical analysis and histological examination of some individual bones. Journal of Agricultural Science, Cambridge 81, 433–4O.CrossRefGoogle Scholar
Young, V. R., Lofgreen, G. D. & Luick, J. R. (1966). The effects of phosphorus depletion and of calcium and phosphorus intake, on the endogenous excretion of these elements by sheep. British Journal of Nutrition 20, 795805.CrossRefGoogle ScholarPubMed