动物营养学报2019，Vol.31Issue(6)：2651-2658,8.DOI:10.3969/j.issn.1006⁃267x.2019.06.025
饲粮蛋白质水平对空怀期云南半细毛羊氮沉积和养分排放的影响
Effects of Dietary Protein Level on Nitrogen Deposition and Nutrient Emissions of Non?Pregnant Yunnan Semi?Fine Wool Ewes
摘要
Abstract
This experiment was conducted to study the effects of dietary protein level on nitrogen deposition and nutrient emissions of non?pregnant Yunnan semi?fine wool ewes, in order to provide a theoretical reference for non?pregnant Yunnan semi?fine wool ewes diet proportion and environmental load reduction. Fifty health non?pregnant Yunnan semi?fine wool ewes with similar body weight and at the age of 38 months were randomly divided into 5 groups with 10 ewes per group. Ewes in the 5 groups were fed diets with different proteins levels [7.60%( group 1), 9.49%(group 2), 11.29%(group 3), 11.56%(group 4) and 14.96%(group 5) , re?spectively] and the same other nutrient levels. All the tested sheep were reared for 19 days, including 14 days of pre?test and 5 days of formal trial. During the formal trial period, five sheep were selected from each group for digestion and metabolism test. The test sheep were raised in a single cage in a metabolic cage. The feces and urine were collected continuously for 5 days, and diet samples were collected. The results showed as follows:1) dietary protein level had no significant effects on dry matter intake and fecal dry matter emission of non?pregnant Yunnan semi?fine wool ewes ( P＞0.05). 2) With the increase of dietary protein level, nitrogen intake was increased significantly ( P＜0.05 or P＜0.01) ; nitrogen deposition rate in group 3 was significantly higher than that in group 1 ( P＜0.05) , but there was no significant difference among other groups ( P＞0.05). 3) With the increase of dietary protein level, fecal nitrogen emission was gradually increased, there was no signif?icant difference between group 2 and groups 1 and 3 ( P＞0.05) , but there was significant difference among other groups ( P＜0.01) ; fecal calcium emission in group 3 was the lowest (5.04 g/d) , which was significant?ly lower than that in group 5 ( P＜0.01) ; fecal phosphorus emission was gradually increased with the increase of dietary protein level, and it in group 5 was significantly higher than that in other groups ( P＜0.05 or P＜0.01). 4) With the increase of dietary protein level, urinary nitrogen emission was gradually increased, there was no significant difference between group 2 and groups 1 and 3 ( P＞0.05) , but there was significant differ?ence among other groups (P＜0.01) ; fecal calcium emission in group 3 was the lowest (1.18 g/d), and it was decreased by 0.53 and 0.78 g/d compared with groups 1 and 5, respectively; urinary phosphorus emission in group 1 was significantly lower than that in group 5 ( P＜0.05) , but there was no significant difference a?mong other groups ( P＞0.05). 5) Fecal and urinary nitrogen total emission in group 5 was significantly higher than that in other groups ( P＜0.01) , fecal and urinary calcium total emission that in group 3 was significantly lower than that in other groups ( P＜0.01) , and fecal and urinary phosphorus total emission in groups 1 and 2 was significantly lower than that in group 5 ( P＜0.01). 6) Fecal nitrogen rate was 42.06% to 72.44% and uri?nary nitrogen rate was 27.56% to 57.94%, the fecal nitrogen rate was gradually decreased and the urinary ni?trogen rate was gradually increased with the increase of dietary protein level. No significant differences were found in fecal and urinary calcium and phosphorus rates among groups ( P＞0.05). By comprehensive consider?ation, under the condition of this experiment, when dietary protein level is 11.29%, the nitrogen deposition of non?pregnant Yunnan semi?fine wool ewes is the best, and the calcium total emission from feces and urine is the lowest. Dietary protein level within a certain range ( 7.06% to 11.56%) has no significant effects on phos?phorus total emission from feces and urine. For non?pregnant Yunnan semi?fine wool ewes, the calcium and phosphorus emissions are mainly from feces, and the excess nitrogen was mainly discharged as urine nitrogen from urine.[ Chinese Journal of Animal Nutrition, 2019, 31(6) :2651?2658]关键词
饲粮蛋白质水平/空怀期/云南半细毛羊/氮沉积/养分排放Key words
dietary protein level/non⁃pregnant period/Yunnan semi⁃fine wool ewes/nitrogen deposition/nu⁃trient emissions分类
农业科技引用本文复制引用
李卫娟,薛白,李银江,王思宇,欧阳依娜,梁家充,洪琼花..饲粮蛋白质水平对空怀期云南半细毛羊氮沉积和养分排放的影响[J].动物营养学报,2019,31(6):2651-2658,8.基金项目
国家绒毛用羊产业技术体系(CARS39⁃08) （CARS39⁃08）
省科技创新人才计划(2018HC017) （2018HC017）
省科技人才和平台计划(2018IC108) （2018IC108）
