关键词: 不同类型栖息地, 狍, 冬季, 雪尿分析, 营养状况

Abstract: Snow-urine analysis has provided a new reliable avenue to assess ungulates nutritional status on northern ranges during winter. In this paper , snow-urine analysis was used to analyze 50 samples of roe deer ( Caproelus caproelus) urines and their urines deposited in snow to assess their nutritional status and its changes in Xiaodong Forest Region and Sanjiang Nature Reserve during winter seasons of 1999 and 2000. Results indicated that urines deposited in snow can be analyzed biochemically for urea nitrogen(UN) , creatinine (CT) , sodium (Na) , potassium (K) , calcium (Ca) and phosphorus (P) to reflect roe deer's nutritional status. Low ratio of urea nitrogen to creatinine (UN∶CT < 4) , potassium to creatinine (K∶CT) and sodium to creatinine (Na∶CT) indicated that roe deers in these two areas remained in an early phase of undernutrition , while roe deers in Sanjiang Nature Reserve during winter season of 2000 were in relatively good condition , which reflected the immediate dynamics relationships between dietary intake , fat depletion and protein catabolism. Under low crude protein and energy content of natural vegetation , and low digestibility of browse during early undernutrition phase, roe deer relied primarily on diet and lipid reserves to partially meet energy requirements , while endogenous protein nitrogen was spared and catabolism was minimal. To make compensation for changes in dietary nitrogen content to some extent , most of the urea nitrogen , K, Na , etc. were reabsorbed in the renal almost remained in a prolonged-reversible tubules and little was lost in the urine. Subadult and juvenile roe deers in these two areas phase of undernutrition characterized by UN∶CT> 4 the same as roe deers in Sanjiang Nature Reserve during winter season of 1999.

Key words: Different types of habitats, Roe deer ( Capreolus capreolus), Winter, Snow-urine analysis, Nutritional status