6Asai Y,Mizuno Y, Yamamoto O, et al . Requirement of copper andzine for Foals in connection with the incidence of epiphysitis [J] . An2 im Sciand Teeh ,1993,64 (12) :1193 - 1500.
7Hirabayashi M ,Matsui Tand Yano H. fermentation of soybean flourwith Aspergillus usamii improves availability of Zn and iron in rats. J .Nutru Sci Vitaminol ,1998,44 (6) :877 - 886.
8Kineaid RL ,Chew BP ,Cronrath JD. zin oxide and amino acids assources of dietary zinc for calves : effects on uptake and immunity. J Dairy Sci ,1997, 80 (7) :1381 - 1388.
9V yas D and Chandra R K. Thym ic facto r act ivity lym2phocyte st imulat ion response and ant ibody p roducingcells in copper deficiency [J]. Nutr. Res. 1985, 3:343-349