3Duffield T F,Kelton D F,et al. Use of test day milk fat and milk protein to detect subclinical ketosis in dairy cattle in Ontario. Can Vet J,1997,38(11) :713-718.
4Escobsa. Effect of varying dietary ratio of sodium and chloride on the response of lactating dairy cows in hot weathcr[J]. J Dairy Sci, 1982,65 : 552- 565.
5Hwang S Y, M J Lee, et al. Monitoring nutritional status of dairy cow in Taiwan using milk protein and milk urea nitrogen[J]. Asian-Aus J Anim Sei,2000,13(12) :1667-1673.
6Johnson H D. Bioclimatology and the adaptation of livestock [M]. NewYork: World Animal Science Elsevier Science Publ Co, 1987.
7Mallonee P G, D K beede,et al. Production and physiological responses of dairy cows to varying dietary potassium during heat stress[J]. J Dairy Sci,1985,68:1479-1487.
8Olbrich S E,Martz F A, et al. Serum biochemical and hematological parameters of heat and cold-tolerant cattle inconstant ambient temperatures of 10. 0 and 32. 2 ℃ [J]. J Dairy Sci, 1971,54:793.
9Sanchez W K, Meguire M A, et al. Macromineral nutrition by heat stress interactions in dairy cattle:review and original research[J]. J Dairy Sci, 1994,77 : 2051- 2079.
10West J W. Effects of heat-street on production in dairy cattle[J]. J Dairy Sci,2003,86:2131-2144.
