composition. Amer. Soc. Anim. Sci. West. 
Sect. Proc. 18: 285. 
Somers, M. 
1961. Factors influencing the secretion of nitrogen 
in sheep saliva: I. The distribution of nitro- 
gen in the mixed and parotid saliva of 
sheep. Aust. J. Exp. Biol. and Med. 39: 111. 
Stewart, D. R. M. 
1967. Analysis of plant epidermis in faeces: A tech- 
nique for studying the food preferences of 
grazing herbivore. J. Appl. Ecol. 4: 83. 
Strasia, C. A. 
1968. A study of the grazing habits and diet selec- 
tion of free grazed or herded sheep on al- 
pine summer range. M.S. thesis, Univ. Wyo., 
Laramie, Wyo. 
Taylor, J. C., and Deriaz, R. E. 
1963. The use of rumen fistulated steers in the di- 
rect determination of nutritive value of ing- 
ested herbage in grazing experiments. J. 
Brit. Grassland Soc. 18: 29. 
Tilley, J. M., and Terry, R. A. 
1963. A two-stage technique for the in vitro diges- 
tion of forage crops. J. Brit. Grassland Soe. 
18: 104. 
Torell, D. T. 
1954. An esophageal fistula for animal nutrition 
studies. J. Anim. Sci. 18: 878. 
132 
Van Dyne, G. M. 
1962. Micro-methods for nutritive evaluation of 
range forage. J. Range Manage. 15: 303. 
and Heady, H. F. 
1965. Botanical composition of sheep and cattle diets 
on mature annual range. Hilgardia 36: 465. 
and Heady, H. F. 
1965. Dietary composition of cattle and sheep graz- 
ing in common on dry annual range. J 
Range Manage. 18: 78. 
and Torell, D. T. 
1964. Development and use of the esophageal fis- 
tula: A review. J. Range Manage. 17: 7. 
Van Soest, P. J. 
1962. The estimation of forage protein digestibility 
and determination of the effects of heat- 
drying upon forages by means of the nitro- 
gen content of acid-detergent fiber. Paper 3. 
Presented at Annu. Meeting Amer. Dairy 
Sci Ass. 16 pp. 
Weir, W. C., and Torell, D. T. 
1959. Selective grazing by sheep as shown by a com- 
parison of the chemical composition of the 
range and pasture forage obtained by 
hand-clipping and that collected by esopha- 
geal fistulated sheep. J. Anim. Sci. 18: 641. 
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