2Miller W J. Using mineral requirement standards in cattle feeding programs and feed formulations [ C ]. Georgia Nutrition Conference for the Feed Industry, Athens: University of Georgia, 1983a: 69-74.
3Miller W J. Phosphorus mutrition, biochemistry, metabolism ad re- quirements in ruminants [ C ]. Paper presented at the meeting of the National Feed Ingredients Association, Chicago, Illinois, 1983 b : 5- 7.
4Kincaid R L, Hillers J K, Cronrath J D. Calcium and Phosphorus supplementation of rations for lactating cows [ J ]. J Dairy Sci, 1981, 64: 754-758.
5Kirchgessner M, Weser U. Complexstability and copper absorption, 4. On the dynamics copper absorption. Z [ J]. Tierphysiol Tierere- nahr Futtermittelkd, 1965, 20: 44-49.
6Huber J T and Price N O. Influence of high dietary calcium and phosphorus and Ca: P ratio on liver copper and iron stores in lacta- ting cows [J]. J Dairy Sei, 1971,54: 429-432.
7O' Dell B L, Newberne P M, Savage J E. Significance of ietary zinc or the growing chicken [J]. J Nutr, 1958, 65: 303-312.
8Pond W G and Oltjen R R. Response of large and medium frame beef steers to protein and zinc supplementation of a corn silagecorn finishing diet [J]. Nutr Rep Int, 1988, 38: 737-743.
9Pond W G and Wallace M H. Effects of gestation-lactation diet calci- um and zinc levels and of parental vitamin A, D and E during gesta- tion on ewe body weight and lamb weight and survival [J]. J Mnim Sci, 1986, 63: 1019-1025.