不同日粮组成对山羊胃肠和血液生化指标的影响及其相关性研究
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摘要
本试验采用装有永久性瘤胃瘘管、十二指肠近端T型瘘管和颈静脉血插管的四只徐淮白山羊(20±2kg)为试验动物，按4×4拉丁方试验设计方案，研究了饲喂由苜蓿干草、羊草及配合精料组成的结构性碳水化合物／粗蛋白(structural
carbohydrate／crude protein：SC／CP)分别为3.62(A)、2.95(B)、2.29(C)、1.65(D)的四种不同日粮对山羊胃肠和血液中部分生化指标的影响及相关性分析。结果表明：
1．瘤胃液pH值随日粮中SC／CP的降低而降低。A、B、C、D四组日粮的瘤胃液pH平均值分别为6.53、6.34、6.19、6.04，A组显著高于C组(P＜0.05)，极显著高于D组(P＜0.01)，与B组差异不显著(P＞0.05)。B组、C组和D组三组间差异不显著(P＞0.05)。从日内动态变化规律来看，瘤胃液pH值均在采食后1～3小时内下降后又开始上升。
2．瘤胃液氨氮浓度随日粮SC／CP比的降低而升高。氨氮浓度的平均值分别由A组的5.63 mg·dl~(-1)升至D组的12.23mg·dl~(-1)，其中A组极显著低于C组和D组(P＜0.01)，与B组差异不显著(P＞0.05)；C组和D组间差异不显著(P＞0.05)。瘤胃液氨氮浓度在采食1～2小时后达到最高，然后开始下降。
3．瘤胃乙酸浓度以B组最高为56.69mmol·L~(-1)，A组最低为52.67mmol·L~(-1)；乙丙比随SC／CP的降低而减小，但四组间差异不显著；瘤胃丙酸、丁酸和总VFA浓度均呈现随SC／CP降低而升高的趋势。瘤胃丙酸和总VFA浓度均以D组最高，显著高于A组(P＜0.05)；瘤胃丁酸浓度以A组最低，极显著低于C组和D组(P＜0.01)，显著低于B组(P＞0.05)。瘤胃VFA浓度在采食后2小时升高，而后缓慢下降，日内波动幅度均以D组最大，A组最小。
4．日粮只对瘤胃中部分游离氨基酸如天门冬氨酸和谷氨酸产生显著影响，天门冬氨酸和谷氨酸浓度随日粮SC／CP的降低而逐渐升高。瘤胃内总FAA以D组最高，极显著高于A组(P＜0.01)，显著高于B组(P＜0.05)，与C组差异不显著(P＞0.05)。
5．十二指肠中各挥发性脂肪酸均以A组最低。A组乙酸浓度极显著低于B组和C组(P＜0.01)，显著低于D组(P＜0.05)，其它三组间差异不显著；不同日粮对丙酸浓度影响差异不显著，但呈现出随日粮SC／CP降低而升高的趋势；丁酸和总VFA受到显著影响，均以C组达到最高。
6．血液pH值不受日粮的影响，在7.52～7.53范围内变动，采食后在6小时内
缓慢降低，然后再回升。
7.血浆尿素氮浓度平均值以B组最高为l2.64mgdl’’，极显著高于D组(P<0.01)，
而A组、B组和C组三组间差异不显著(P>.05)，在采食后2小时内升高而后降低，
日内波动幅度以D组最大，达到了4.36mgdi一，。
8.血浆乙酸、丙酸、丁酸及总VFA浓度都呈现出随日粮SC/CP的降低而升高
的趋势，D组均极显著高于A组和B组(P<0 .01)，都在采食后1~2小时内升高，
然后开始下降。
9.血糖浓度以B组最低，显著低于A组和D组(P<0.05)，但A组、C组和D
组三组间差异不显著(P>.05)。
10.血浆游离脂肪酸浓度随日粮SC/CP的降低而呈现出降低的趋势，A组极显
著高于c组和D组(P<0.01)，与B组差异不显著(P>.05)。B组极显著高于D组
(P<0.01)，显著高于C组(P<0.05)，C组和D组间差异不显著(P>.05)。各组于采食
后1一2小时内升高，后降低。
11.本试验条件下四种日粮对血浆各游离氨基酸浓度没有显著影响，对总游离
氨基酸也没有显著影响，以C组中最高，为5.1 lmgml一，，B组中最低为4.36mgml一，。
12.从相关性分析上看，C组和D组血浆尿素氮浓度和血浆游离脂肪酸浓度均
与瘤胃氨氮浓度呈显著正相关。D组血糖与瘤胃丁酸呈显著正相关，血浆NEFA
与瘤胃丙酸呈显著负相关。血浆中VFA与瘤胃中VFA呈现极显著相关。
Four young Xuhuai white goats fitted with permanent ruminal cannulae, proximal duodenal T-shaped cannulae and jugular fistulae were used to determine the effect of four different ratios of structural carbohydrate: crude protein(SC/CP) in diets on the gastrointestinal and some blood biochemical indices and correlation analysis. The experimental design was 4 4 Latin square, in which the four ratios of SC/CP treatments were: 3.62(A), 2.95(B), 2.29(C), 1.65(D). The results showed that:
1 .Rumen pH decreased with the decrease of SC/CP. The average of rumen pH in A, B, C and D was 6.53, 6.34, 6.19 and 6.04 respectively. Rumen pH in A group was much higher than that in C group (P<0.05) and D group (P<0.01). There had no significant difference between A and B group, and had no significant difference among B, C and D group either(P>0.05). From the changing rules of rumen pH in 24 hours, it decreased after feeding 1-3 hours, then increased until the next time's feeding.
2.Rumen ammonia-N(NH3-N) concentration increased with the decrease of SC/CP. NH3-N concentration increased from 5.63 to 12.23m.g-dl-1 with SC/CP changing from A to D group. NHa-N concentration in A group was lower than C and D significantly (PO.01). But result showed that there was no difference between A and B group, neither between C and D group(P>0.05). NH3-N concentration increased to the highest point after feeding l-2hours, then decreased until the next time's feeding.
3.The highest acetate concentration was observed in B group, the lowest in A group. With the decrease of SC/CP, the ratio of acetate: propionate decreased, but there was no significant difference among four diets (P>0.05). The rumen propionate, butyrate and total volatile fatty acid (TVFA) concentration increased with the decrease of SC/CP. The propionate and total VFA concentration in D group was higher than that in A group significantly(P<0.05). The butyrate concentration in A group was lowest, which was significantly lower than that in C , D group(P<0.01) and B group(P<0.05). The TVFA concentration increased after feeding 2 hours, then decreased gradually. The greatest changing range of VFA concentration in 24hours was observed in D group, and the slightest was in A group.
4.The diets had no significant effect on the concentration of free amino acid(FAA) except aspartic acid (Asp) and glutamic acid (Glu). Asp and Glu concentration were increased gradually with the decrease of SC/CP. The highest rumen total free amino acid (TFAA) was observed in D group, higher than that in A group(P<0.01) and B
group(P<0.05), and showed no significant difference with C group(P>.05).
5.Each kind of VFA in duodenum was lowest in A group. The acetate concentration of A group was much lower than B and C group(P<0.01) and D group(P<0.05), while no significant difference was found among B, C, and D group(P>0.05). Diets had no effect on propionate concentration, but had a increasing trend with the decrease of SC/CP. The butyrate and TVFA concentration were affected by the diets significantly, and the highest concentrations were all in C group.
6.Blood pH was not affected by the diets significantly, ranging from 7.52 to 7.53 in four diets. Blood pH gradually decreased after feeding 6 hours, then increased.
7.The highest plasma Urea-N concentration was observed in B group, which was much higher than that in D group(P<0.01). There was no significant difference among A, B and C group(P>0.05). The plasma Urea-N concentration increased after feeding 2 hours, then decreased. The changing range of the plasma Urea-N concentration in each group was different, but D group was greatest.
S.The plasma acetate, propionate, butyrate and TVFA appeared to be increasing with the decrease of SC/CP, D group showed a significant difference with A and B group(P<0.01), the concentration of VFA increased after feeding 1-2 hours, then decreased.
9.The lowest concentration of blood glucose was found in B group, which is significantly lower than A and D group(P<0.05). No significant difference had been found among A, C and D gro
carbohydrate／crude protein：SC／CP)分别为3.62(A)、2.95(B)、2.29(C)、1.65(D)的四种不同日粮对山羊胃肠和血液中部分生化指标的影响及相关性分析。结果表明：
1．瘤胃液pH值随日粮中SC／CP的降低而降低。A、B、C、D四组日粮的瘤胃液pH平均值分别为6.53、6.34、6.19、6.04，A组显著高于C组(P＜0.05)，极显著高于D组(P＜0.01)，与B组差异不显著(P＞0.05)。B组、C组和D组三组间差异不显著(P＞0.05)。从日内动态变化规律来看，瘤胃液pH值均在采食后1～3小时内下降后又开始上升。
2．瘤胃液氨氮浓度随日粮SC／CP比的降低而升高。氨氮浓度的平均值分别由A组的5.63 mg·dl~(-1)升至D组的12.23mg·dl~(-1)，其中A组极显著低于C组和D组(P＜0.01)，与B组差异不显著(P＞0.05)；C组和D组间差异不显著(P＞0.05)。瘤胃液氨氮浓度在采食1～2小时后达到最高，然后开始下降。
3．瘤胃乙酸浓度以B组最高为56.69mmol·L~(-1)，A组最低为52.67mmol·L~(-1)；乙丙比随SC／CP的降低而减小，但四组间差异不显著；瘤胃丙酸、丁酸和总VFA浓度均呈现随SC／CP降低而升高的趋势。瘤胃丙酸和总VFA浓度均以D组最高，显著高于A组(P＜0.05)；瘤胃丁酸浓度以A组最低，极显著低于C组和D组(P＜0.01)，显著低于B组(P＞0.05)。瘤胃VFA浓度在采食后2小时升高，而后缓慢下降，日内波动幅度均以D组最大，A组最小。
4．日粮只对瘤胃中部分游离氨基酸如天门冬氨酸和谷氨酸产生显著影响，天门冬氨酸和谷氨酸浓度随日粮SC／CP的降低而逐渐升高。瘤胃内总FAA以D组最高，极显著高于A组(P＜0.01)，显著高于B组(P＜0.05)，与C组差异不显著(P＞0.05)。
5．十二指肠中各挥发性脂肪酸均以A组最低。A组乙酸浓度极显著低于B组和C组(P＜0.01)，显著低于D组(P＜0.05)，其它三组间差异不显著；不同日粮对丙酸浓度影响差异不显著，但呈现出随日粮SC／CP降低而升高的趋势；丁酸和总VFA受到显著影响，均以C组达到最高。
6．血液pH值不受日粮的影响，在7.52～7.53范围内变动，采食后在6小时内
缓慢降低，然后再回升。
7.血浆尿素氮浓度平均值以B组最高为l2.64mgdl’’，极显著高于D组(P<0.01)，
而A组、B组和C组三组间差异不显著(P>.05)，在采食后2小时内升高而后降低，
日内波动幅度以D组最大，达到了4.36mgdi一，。
8.血浆乙酸、丙酸、丁酸及总VFA浓度都呈现出随日粮SC/CP的降低而升高
的趋势，D组均极显著高于A组和B组(P<0 .01)，都在采食后1~2小时内升高，
然后开始下降。
9.血糖浓度以B组最低，显著低于A组和D组(P<0.05)，但A组、C组和D
组三组间差异不显著(P>.05)。
10.血浆游离脂肪酸浓度随日粮SC/CP的降低而呈现出降低的趋势，A组极显
著高于c组和D组(P<0.01)，与B组差异不显著(P>.05)。B组极显著高于D组
(P<0.01)，显著高于C组(P<0.05)，C组和D组间差异不显著(P>.05)。各组于采食
后1一2小时内升高，后降低。
11.本试验条件下四种日粮对血浆各游离氨基酸浓度没有显著影响，对总游离
氨基酸也没有显著影响，以C组中最高，为5.1 lmgml一，，B组中最低为4.36mgml一，。
12.从相关性分析上看，C组和D组血浆尿素氮浓度和血浆游离脂肪酸浓度均
与瘤胃氨氮浓度呈显著正相关。D组血糖与瘤胃丁酸呈显著正相关，血浆NEFA
与瘤胃丙酸呈显著负相关。血浆中VFA与瘤胃中VFA呈现极显著相关。
Four young Xuhuai white goats fitted with permanent ruminal cannulae, proximal duodenal T-shaped cannulae and jugular fistulae were used to determine the effect of four different ratios of structural carbohydrate: crude protein(SC/CP) in diets on the gastrointestinal and some blood biochemical indices and correlation analysis. The experimental design was 4 4 Latin square, in which the four ratios of SC/CP treatments were: 3.62(A), 2.95(B), 2.29(C), 1.65(D). The results showed that:
1 .Rumen pH decreased with the decrease of SC/CP. The average of rumen pH in A, B, C and D was 6.53, 6.34, 6.19 and 6.04 respectively. Rumen pH in A group was much higher than that in C group (P<0.05) and D group (P<0.01). There had no significant difference between A and B group, and had no significant difference among B, C and D group either(P>0.05). From the changing rules of rumen pH in 24 hours, it decreased after feeding 1-3 hours, then increased until the next time's feeding.
2.Rumen ammonia-N(NH3-N) concentration increased with the decrease of SC/CP. NH3-N concentration increased from 5.63 to 12.23m.g-dl-1 with SC/CP changing from A to D group. NHa-N concentration in A group was lower than C and D significantly (PO.01). But result showed that there was no difference between A and B group, neither between C and D group(P>0.05). NH3-N concentration increased to the highest point after feeding l-2hours, then decreased until the next time's feeding.
3.The highest acetate concentration was observed in B group, the lowest in A group. With the decrease of SC/CP, the ratio of acetate: propionate decreased, but there was no significant difference among four diets (P>0.05). The rumen propionate, butyrate and total volatile fatty acid (TVFA) concentration increased with the decrease of SC/CP. The propionate and total VFA concentration in D group was higher than that in A group significantly(P<0.05). The butyrate concentration in A group was lowest, which was significantly lower than that in C , D group(P<0.01) and B group(P<0.05). The TVFA concentration increased after feeding 2 hours, then decreased gradually. The greatest changing range of VFA concentration in 24hours was observed in D group, and the slightest was in A group.
4.The diets had no significant effect on the concentration of free amino acid(FAA) except aspartic acid (Asp) and glutamic acid (Glu). Asp and Glu concentration were increased gradually with the decrease of SC/CP. The highest rumen total free amino acid (TFAA) was observed in D group, higher than that in A group(P<0.01) and B
group(P<0.05), and showed no significant difference with C group(P>.05).
5.Each kind of VFA in duodenum was lowest in A group. The acetate concentration of A group was much lower than B and C group(P<0.01) and D group(P<0.05), while no significant difference was found among B, C, and D group(P>0.05). Diets had no effect on propionate concentration, but had a increasing trend with the decrease of SC/CP. The butyrate and TVFA concentration were affected by the diets significantly, and the highest concentrations were all in C group.
6.Blood pH was not affected by the diets significantly, ranging from 7.52 to 7.53 in four diets. Blood pH gradually decreased after feeding 6 hours, then increased.
7.The highest plasma Urea-N concentration was observed in B group, which was much higher than that in D group(P<0.01). There was no significant difference among A, B and C group(P>0.05). The plasma Urea-N concentration increased after feeding 2 hours, then decreased. The changing range of the plasma Urea-N concentration in each group was different, but D group was greatest.
S.The plasma acetate, propionate, butyrate and TVFA appeared to be increasing with the decrease of SC/CP, D group showed a significant difference with A and B group(P<0.01), the concentration of VFA increased after feeding 1-2 hours, then decreased.
9.The lowest concentration of blood glucose was found in B group, which is significantly lower than A and D group(P<0.05). No significant difference had been found among A, C and D gro
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37. Merchen NR, Firkins JL. Berger LL. Effect of intake and forage level on ruminal turnover rates, bacterial protein synthesis and duodenal amino acid flows in sheep. J. Anim. Sci. 1986,62(1): 216-225.
38. Hart SP. Associative effects of sorghum silage and sorghum grain diets. J. Anim. Sci. 1987,64: 1779-1789.
39. Vanzant ES, Cochran RC, Jacques KA, Beharka AA. Influence of level of
supplementation and type of grain in supplements on intake, utilization of harvested, early-growing-season, bluestem-range forage by beef steers. J. Anim. Sci. 1990, 68(5): 1457-1468.
40．王星凌，朱承满，李世英等．运用Rusitee系统研究不同碳水化合物对麦秸消化率的影响机理．山东农业科学．2002，1：42-44．
41. DelGiudiee GD, Seal US. Classifying winter undemutrition in deer via serum and urinary urea nitrogen. Wildl Soci Bu11.1988,16(1): 27-32
42. Cook RC, Cook JG, Murray DL et al. Development of predictive models of nutritional condition for rocky mountain elk. J. Wildl Manage.2001.65(4): 973-987.
43. DelGiudice GD, Mech LD, Seal US. Winter undemutrition and serum and uninary urea nitrogen of white-tailed deer. J. Wildl Manage. 1994.58(2): 539-550.
44. Adam CL, Kyle CE, Young P, Atkinson T. Effect of nutritional growth restriction on timing of reproductive development and plasma concentrations of insulin-like growth factor-1 and growth hormone in male red deer(Cervus elaphus) reared in constant photoperiod. Anim. Sci. 1995,61(1): 155-160.
45. Bahnak BR, Holiand JC, Verme LJ. Seasonal and nutritional influences on growth hormone and thyroid activity in white-tailed deer. J Wildl Manage. 1981, 45(1): 140-147.
46. Brown RD, Hellgren EC, Abbgott M. Effects of dietary energy and protein restriction on nutritional indices of female white-tailed deer. J. Wildl Mange. 1995, 59(3): 595-609.
47. Angelo A, Saula DK, Edward K, Antonio T. Nonesterified fatty acids and endothelial dysfunction. International Congress Series 1253(2003): 139-145.
48. Lewis D. Blood -urea concentration in relation to protein utilization in the ruminant. J.Agri. Sci. 1957,48: 438-446.
49. Chikhou FH, Moloney AP, Allen P, Quirke JF. Long-term effects of cimaterol in Friesian steers: Ⅰ. Growth, feed efficiency, and selected carcass traits. J. Anim Sei, 1993, 71(4): 906-913.
50. Preston RL, Schnakenberg DD, Pfander WH. Protein utilization in ruminants. Ⅰ.Blood urea nitrogen as affected by protein intake. J. Nutr. 1965.86:281-288.
51. AI-Dehneh et al. Incorporation of recycled urea-N into ruminal bacteria flowing to the small intestine of dairy cows fed a high-grain or high-forage diet. Anim. Feed Sci. Technol. 1997,68: 327-338.
52. Swanson SW. Protein Requirements of Cattle. 1982, P 183-197
53. Langland JP. Assessing the nutrient status of herbivores. In: The nutrition of herbivores.(Edited by Hacker JB and Ternouth JH) Academic press. 1987,363-390.
54. Payne JM, Dew SM, Manston R et al. The use of a metabolic profile test in dairy herds. Vet. Rec. 1970,87: 150-158.
55．乔惠理主编．动物生理大实验．北京农业大学出版社，1994．
56. Beige A, Bakir B, Ozeelik A. A technique of duodenal cannulation in sheep. Small Ruminant. 2002,44:167-171.
57. Horigane A, Araki T. Technical note: development of a duodenal cannula for sheep. J. Anim. Sci. 1992, 70: 1216-1219.
58. Coley Ⅲ, muphy RN. Technical note: a device for obtaining time-integrated samples
of ruminal fluid. J. Anim. Sci. 1999,77: 2540-2544.
59. Ludden PA, Kerley MS. Amino acid and energy interrelationship in growing beef steers: Ⅰ. the effect of level of feed intake on ruminal characteristics and intestinal amino acid flows. J. Anim. Sci. 1997,75:2550-2560
60. Sticker LS, Thompson DL, Bunting LD, Fernandez JM. Dietary protein and energy restriction in Mares: Rapid changes in plasma metabolite and hormone concentrations during dietary alteration. J. Anim. Sci. 1996,74:1326-1335.
61．王继贵主编．临床生化检验(第二版)．湖南科学技术出版社．1996．
62．熊本海，卢德勋等．绵羊瘤胃VFA吸收效率及模型参数的研究．动物营养学报．1999，11(增刊)：248-255．
63. Remond D, Chaise JP, Delval E, Poncet C. Net flux of metabolites across the ruminal wall of sheep fed twice a day with orchardgrass hay. J. Anim. Sci. 1993, 71(9): 2529-2538.
64. Remesy C, Demigne C. Determination of volatile fatty acids in plasma after ethanolic extraction. Bioehem. J. 1974,141: 85-91.
65. Rubio LA. Determination of diaminopimelie acid in rat feces by highperformance liquid chromatography using the Pico Tag method. J. Chromatogr. B. 2003,784: 125-129.
66. Alhadhrami G, Huber JT. Effect of Alfalfa hay of varying fiber fed at 35 or 50% of diet on lactation and nutrient utilization by dairy cow. J. Dairy Sei. 1992,75: 3091-3099.
67. Verma DN, DassRS, Mehra UR. Volatile fatty acid production in crossbred cattle fed ammoniated wheat straw and molassess. J. Nucl. Agric. Biol. 1996, 25(4): 242-246.
68. National research Council. Nutrient requirements of beef cattle.7th.Revised Edition. Washington, D.C. National Academy Press. 1996,85-97.
69. Cotta MA, Hespell RB. Protein and amino acid metabolism of rumen bacteria. In: "Control of digestion and metabolism in ruminants". Prentice-Hall, Englewood, 1986, P122.
70．姜卫红，韩正康。在非蛋白氮(NPN)和甲醛处理的曰粮条件下几种与瘤胃代谢有关的酶活力的研究．南京农业大学学报．1986，2：76-85．
71. Satter LD, Slyter L. Effect of ammonia concentration on rumen microbial protein production in vitro. Br. J. Nutr. 1974, 32: 199-208.
72. Preston TR, Leng KA. Matching ruminant production system with available resources in the tropics and sub-tropics. Penambul Books. Armidale, 1987.
73. Hsu JT, Fahey GC, Berger LL, Mackie RI, Merchen NR. Manipulation of nitrogen digestion by sheep using defaunation and various nitrogen supplementation regimens. J. Anim. Sci. 1991,69(3): 1290-1299.
74. Flachowsky G, Koch H, Tiroke K, Matthey M. Influence of ratio between wheat straw and ground barley, ground corn or dried sugar beet pulp on in sacco dry matter degradation of ryegrass and wheat straw, rumen fermentation and apparent digestibility in sheep. Arch Tierenahr. 1993, 43(2): 157-167.
75. Blaxter KL. The energy metabolism of ruminants. Hutchinson, London, 1965
76. Φrskov ER, Grubb DA, Smith JS. Efficiency of utilization of volatile fatty acids for
maintenance and energy retention by sheeo. Br. J. Nutri. 1979,41:541-552
77．甄玉国，马宁．绵羊、山羊采食不同种类多纤维粗饲料的瘤胃发酵参数的比较研究．吉林农业大学学报．1998，20(3)：66-70．
78．卢德勋．乳牛八大营养工程技术．饲料广角．2001，9：1-6．
79. Bergman EN. Energy contributions of volatile fatty acid from the gastrointestinal tractin various species. Physiol. Rev. 1990, 70: 567-590.
81. Bugaut M. Occurrence absorption and metabolism of short chain fatty acid in the digestive tract of mammals. Comparative Biochemistry and Physiology, 1987, 86B: 439-472.
82. Byramt MP et al. Apparent incorporation of ammonia and amino carbon during growth of selected species of ruminal bacteria. J. Dairy Sci. 1963,46: 150-165.
83. Argyle JL, Baldwin RL. Effects of amino acids and peptides on rumen microbial growth yields. J. Dairy Sci.1989,72: 2017-2027.
84. Ovens FN, Seerist DS, Hill W J, Gill DR. Acidosis in cattle: a review. J. Anim. Sci. 1998,76(1): 275-286.
85. Egan AR, Kellaway RC. Evaluation of nitrogen metabolites as indices of nitrogen utilization in sheep given frozen and dry mature herbages. Br. J. Nutr. 1971, 26(3): 335-351.
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8．谭支良，卢德勋等．绵羊日粮不同碳水化合物比例对纤维物质在消化道不同部位流通量和消化率的影响．动物营养学报．1999，11(4)：29-38．
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35. Isaaeson HR, Hinds FC, Byrant MP, Owens FN. Efficiency of energy utilization by mixed rumen bacteria in continuous culture. J. Dairy Sci. 1975,58:1645-1659.
36. Istasse L, Φrskov ER. The effect of intermittent and infusion of propionate acid on plasma insulin. Can. J. Anim. Sei.1984, 64: 148-149.
37. Merchen NR, Firkins JL. Berger LL. Effect of intake and forage level on ruminal turnover rates, bacterial protein synthesis and duodenal amino acid flows in sheep. J. Anim. Sci. 1986,62(1): 216-225.
38. Hart SP. Associative effects of sorghum silage and sorghum grain diets. J. Anim. Sci. 1987,64: 1779-1789.
39. Vanzant ES, Cochran RC, Jacques KA, Beharka AA. Influence of level of
supplementation and type of grain in supplements on intake, utilization of harvested, early-growing-season, bluestem-range forage by beef steers. J. Anim. Sci. 1990, 68(5): 1457-1468.
40．王星凌，朱承满，李世英等．运用Rusitee系统研究不同碳水化合物对麦秸消化率的影响机理．山东农业科学．2002，1：42-44．
41. DelGiudiee GD, Seal US. Classifying winter undemutrition in deer via serum and urinary urea nitrogen. Wildl Soci Bu11.1988,16(1): 27-32
42. Cook RC, Cook JG, Murray DL et al. Development of predictive models of nutritional condition for rocky mountain elk. J. Wildl Manage.2001.65(4): 973-987.
43. DelGiudice GD, Mech LD, Seal US. Winter undemutrition and serum and uninary urea nitrogen of white-tailed deer. J. Wildl Manage. 1994.58(2): 539-550.
44. Adam CL, Kyle CE, Young P, Atkinson T. Effect of nutritional growth restriction on timing of reproductive development and plasma concentrations of insulin-like growth factor-1 and growth hormone in male red deer(Cervus elaphus) reared in constant photoperiod. Anim. Sci. 1995,61(1): 155-160.
45. Bahnak BR, Holiand JC, Verme LJ. Seasonal and nutritional influences on growth hormone and thyroid activity in white-tailed deer. J Wildl Manage. 1981, 45(1): 140-147.
46. Brown RD, Hellgren EC, Abbgott M. Effects of dietary energy and protein restriction on nutritional indices of female white-tailed deer. J. Wildl Mange. 1995, 59(3): 595-609.
47. Angelo A, Saula DK, Edward K, Antonio T. Nonesterified fatty acids and endothelial dysfunction. International Congress Series 1253(2003): 139-145.
48. Lewis D. Blood -urea concentration in relation to protein utilization in the ruminant. J.Agri. Sci. 1957,48: 438-446.
49. Chikhou FH, Moloney AP, Allen P, Quirke JF. Long-term effects of cimaterol in Friesian steers: Ⅰ. Growth, feed efficiency, and selected carcass traits. J. Anim Sei, 1993, 71(4): 906-913.
50. Preston RL, Schnakenberg DD, Pfander WH. Protein utilization in ruminants. Ⅰ.Blood urea nitrogen as affected by protein intake. J. Nutr. 1965.86:281-288.
51. AI-Dehneh et al. Incorporation of recycled urea-N into ruminal bacteria flowing to the small intestine of dairy cows fed a high-grain or high-forage diet. Anim. Feed Sci. Technol. 1997,68: 327-338.
52. Swanson SW. Protein Requirements of Cattle. 1982, P 183-197
53. Langland JP. Assessing the nutrient status of herbivores. In: The nutrition of herbivores.(Edited by Hacker JB and Ternouth JH) Academic press. 1987,363-390.
54. Payne JM, Dew SM, Manston R et al. The use of a metabolic profile test in dairy herds. Vet. Rec. 1970,87: 150-158.
55．乔惠理主编．动物生理大实验．北京农业大学出版社，1994．
56. Beige A, Bakir B, Ozeelik A. A technique of duodenal cannulation in sheep. Small Ruminant. 2002,44:167-171.
57. Horigane A, Araki T. Technical note: development of a duodenal cannula for sheep. J. Anim. Sci. 1992, 70: 1216-1219.
58. Coley Ⅲ, muphy RN. Technical note: a device for obtaining time-integrated samples
of ruminal fluid. J. Anim. Sci. 1999,77: 2540-2544.
59. Ludden PA, Kerley MS. Amino acid and energy interrelationship in growing beef steers: Ⅰ. the effect of level of feed intake on ruminal characteristics and intestinal amino acid flows. J. Anim. Sci. 1997,75:2550-2560
60. Sticker LS, Thompson DL, Bunting LD, Fernandez JM. Dietary protein and energy restriction in Mares: Rapid changes in plasma metabolite and hormone concentrations during dietary alteration. J. Anim. Sci. 1996,74:1326-1335.
61．王继贵主编．临床生化检验(第二版)．湖南科学技术出版社．1996．
62．熊本海，卢德勋等．绵羊瘤胃VFA吸收效率及模型参数的研究．动物营养学报．1999，11(增刊)：248-255．
63. Remond D, Chaise JP, Delval E, Poncet C. Net flux of metabolites across the ruminal wall of sheep fed twice a day with orchardgrass hay. J. Anim. Sci. 1993, 71(9): 2529-2538.
64. Remesy C, Demigne C. Determination of volatile fatty acids in plasma after ethanolic extraction. Bioehem. J. 1974,141: 85-91.
65. Rubio LA. Determination of diaminopimelie acid in rat feces by highperformance liquid chromatography using the Pico Tag method. J. Chromatogr. B. 2003,784: 125-129.
66. Alhadhrami G, Huber JT. Effect of Alfalfa hay of varying fiber fed at 35 or 50% of diet on lactation and nutrient utilization by dairy cow. J. Dairy Sei. 1992,75: 3091-3099.
67. Verma DN, DassRS, Mehra UR. Volatile fatty acid production in crossbred cattle fed ammoniated wheat straw and molassess. J. Nucl. Agric. Biol. 1996, 25(4): 242-246.
68. National research Council. Nutrient requirements of beef cattle.7th.Revised Edition. Washington, D.C. National Academy Press. 1996,85-97.
69. Cotta MA, Hespell RB. Protein and amino acid metabolism of rumen bacteria. In: "Control of digestion and metabolism in ruminants". Prentice-Hall, Englewood, 1986, P122.
70．姜卫红，韩正康。在非蛋白氮(NPN)和甲醛处理的曰粮条件下几种与瘤胃代谢有关的酶活力的研究．南京农业大学学报．1986，2：76-85．
71. Satter LD, Slyter L. Effect of ammonia concentration on rumen microbial protein production in vitro. Br. J. Nutr. 1974, 32: 199-208.
72. Preston TR, Leng KA. Matching ruminant production system with available resources in the tropics and sub-tropics. Penambul Books. Armidale, 1987.
73. Hsu JT, Fahey GC, Berger LL, Mackie RI, Merchen NR. Manipulation of nitrogen digestion by sheep using defaunation and various nitrogen supplementation regimens. J. Anim. Sci. 1991,69(3): 1290-1299.
74. Flachowsky G, Koch H, Tiroke K, Matthey M. Influence of ratio between wheat straw and ground barley, ground corn or dried sugar beet pulp on in sacco dry matter degradation of ryegrass and wheat straw, rumen fermentation and apparent digestibility in sheep. Arch Tierenahr. 1993, 43(2): 157-167.
75. Blaxter KL. The energy metabolism of ruminants. Hutchinson, London, 1965
76. Φrskov ER, Grubb DA, Smith JS. Efficiency of utilization of volatile fatty acids for
maintenance and energy retention by sheeo. Br. J. Nutri. 1979,41:541-552
77．甄玉国，马宁．绵羊、山羊采食不同种类多纤维粗饲料的瘤胃发酵参数的比较研究．吉林农业大学学报．1998，20(3)：66-70．
78．卢德勋．乳牛八大营养工程技术．饲料广角．2001，9：1-6．
79. Bergman EN. Energy contributions of volatile fatty acid from the gastrointestinal tractin various species. Physiol. Rev. 1990, 70: 567-590.
81. Bugaut M. Occurrence absorption and metabolism of short chain fatty acid in the digestive tract of mammals. Comparative Biochemistry and Physiology, 1987, 86B: 439-472.
82. Byramt MP et al. Apparent incorporation of ammonia and amino carbon during growth of selected species of ruminal bacteria. J. Dairy Sci. 1963,46: 150-165.
83. Argyle JL, Baldwin RL. Effects of amino acids and peptides on rumen microbial growth yields. J. Dairy Sci.1989,72: 2017-2027.
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