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为节约成本、提高养羊经济效益,试验从中卫山羊羔羊的断奶月龄和母羊的营养水平两方面着手,研究羔羊早期断奶的可行性。结果显示:在母羊不同营养水平条件下,羔羊分别于3、4、5月龄断奶,对其生长发育的各项指标的影响都不大明显;虽然5月龄断奶羔羊体重、体尺指标略高于3、4月龄断奶的羔羊,但差异不显著。实际生产中,使用营养水平较低的日粮饲喂中卫山羊母羊以及中卫山羊羔羊3月龄断奶是可行的。 相似文献
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中卫山羊和内蒙阿拉善绒山羊母羊体重体尺间差异不显著（P＞0．05），中阿杂种母羊周岁时的体重明显高于亲本（P＜0．05），杂种优势率为12．26％，体尺间差异不显著（P＞0．05）；中阿杂种成年母羊的体高明显高于亲本（P＜0．01），杂种优势率为4．42％，胸围显著高于亲本（P＜0．05），杂种优势率为2．26％，体长、管围和体重明显低于亲本（P＜0．05）。内蒙阿拉善绒山羊母羊绒毛产量明显高于中卫山羊（P＜0．01）；杂种母羊绒产量界于双亲之间，周岁时显著低于内蒙阿拉善绒山羊（P＜0．05），与中卫山羊间差异不显著（P＞0．05），无杂种优势；成年时明显低于内蒙阿拉善绒山羊（P＜0．01），显著高于中卫山羊（P＜0．05），杂种优势率为1．5％。中卫山羊母羊粗毛产量明显高于内蒙阿拉善绒山羊母羊和阿杂种母羊（P＜0．01），内蒙阿拉善绒山羊母羊和中阿杂种母羊粗毛产量间差异不显著（P＞0．05），绒毛自然长度间无差异（P＞0．05），粗毛长度在周岁时无差异性，成年时中卫山羊明显高于内蒙阿拉善绒山羊母羊和中阿杂种母羊（P＜0．01）。 相似文献
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小尾寒羊泌乳期母羊能量需要量及代谢规律研究 总被引：4，自引：0，他引：4
选择有代表性的小尾寒羊泌乳母羊6只，分成哺育单羔和双羔两组，每组3只，分泌乳前期（1～30天），泌乳中期（31～60天）和泌乳后期（61～90天）3个阶段进行饲养试验、消化代谢试验、呼吸测热试验及屠宰试验等研究。两组试羊均按NRC（1978）推荐的绵羊泌乳期哺育双羔母羊能量需要量供给代谢能和其它养分。结果表明，在本研究条件下，小尾寒羊泌乳母羊（包括哺育单、双羔者）在整个泌乳期内的平均日干物质（DM）、有机物质（OM）、代谢能（ME）和泌乳量分别为1689g，1571g，19．893MJ和653g。DM、OM和总能（GE）表观消化率分别为70.71％，72．58％和70．34％，代谢率（MEI／DEI）为84．89％。甲烷能占GEI的9．18％。每日畜体产热量（HP）为625．5KJ／kgW0.75。研究还表明：小尾寒羊泌乳母羊的每日维持代谢能和净能需要量分别为582．6和460KJ／kgW0.75，每户1kg原乳需要10802KJ的代谢能。维持效率为0．790泌乳效率为0．479，HI占GEI的18．10％。分析结果证明，试羊的泌乳量、采食量、畜体产热量和能量转化效率在单、双羔之间均无显著差异（P＞0．05）。小尾寒羊泌乳母羊的代谢能总需要量（MER）可用下式估计：羊羔：MER＝576．9W0.75＋10810M；双羔：MER＝588．2W0.75＋10794M；平均：MER＝582．6W0.75＋1 相似文献
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中卫山羊与内蒙阿拉善绒山羊的杂交效果分析 总被引：1，自引：0，他引：1
中卫山羊和内蒙阿拉善绒山羊母羊体重体尺间差异不显著 (P >0 0 5 ) ,中阿杂种母羊周岁时的体重明显高于亲本 (P <0 0 5 ) ,杂种优势率为 12 2 6 % ,体尺间差异不显著 (P >0 0 5 ) ;中阿杂种成年母羊的体高明显高于亲本 (P <0 0 1) ,杂种优势率为 4 4 2 % ,胸围显著高于亲本 (P <0 0 5 ) ,杂种优势率为 2 2 6 % ,体长、管围和体重明显低于亲本 (P <0 0 5 )。内蒙阿拉善绒山羊母羊绒毛产量明显高于中卫山羊 (P <0 0 1) ;杂种母羊绒产量界于双亲之间 ,周岁时显著低于内蒙阿拉善绒山羊 (P <0 0 5 ) ,与中卫山羊间差异不显著 (P >0 0 5 ) ,无杂种优势 ;成年时明显低于内蒙阿拉善绒山羊 (P <0 0 1) ,显著高于中卫山羊 (P <0 0 5 ) ,杂种优势率为 1 5 %。中卫山羊母羊粗毛产量明显高于内蒙阿拉善绒山羊母羊和阿杂种母羊 (P <0 0 1) ,内蒙阿拉善绒山羊母羊和中阿杂种母羊粗毛产量间差异不显著 (P >0 0 5 ) ,绒毛自然长度间无差异 (P >0 0 5 ) ,粗毛长度在周岁时无差异性 ,成年时中卫山羊明显高于内蒙阿拉善绒山羊母羊和中阿杂种母羊 (P <0 0 1)。 相似文献
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热应激对猪肉品质的影响及其机制的研究进展 总被引：1，自引：0，他引：1
在养殖过程中,热应激会影响猪的生理机能,改变猪肉的生化特性,使猪肉品质下降。因此,研究热应激影响猪肉品质变化的规律,对于指导实际生产具有十分重要的意义。作者综述了热应激对猪肉品质的影响,并从机体代谢改变的角度分析了肉质变化的机制,为进一步研究热应激与肉品质的关系提供新的思路。 相似文献
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Malan DD Scheele CW Buyse J Kwakernaak C Siebrits FK van der Klis JD Decuypere E 《British poultry science》2003,44(2):309-315
1. Male chickens of 7 genetic lines, consisting of two pure sire and two pure dam populations, a commercial broiler cross and two slow-growing chicken lines (Label Rouge, LR and Mechelse Koekoek, MK) were reared from 1 to 37 d of age. The chickens received a two-phase dietary regime and were subjected to low ambient temperature. 2. The experimental aim was to investigate relationships between susceptibility to ascites and heat production. 3. Body weight gain (BWG), food intake and food conversion ratio (FCR) were determined. Ascites mortality, arterial pressure index (API=right ventricular/total ventricular weight ratio), haematocrit values, proportional lung weight (lung weight/body weight x 100), plasma thyroid hormones (thyroxine, T4 and triiodothyronine, T3) and arterial blood gas pressures (pCO2 and pO2) were determined. The heat production per kg metabolic body weight (H/W0.75) and total heat production (H) were calculated for the period 16 to 33 d using an energy balance study according to the comparative slaughter method. 4. The two breeder sire lines had high BWG and low FCR and high but different incidences of ascites compared with the slow-growing ascites resistant LR and MK lines with notable high FCR. The broiler cross and slower-growing breeder dam lines had a similar and relatively lower incidence of ascites mortality. 5. The fast-growing chickens had low H/W0.75 values compared with slow-growing lines. 6. These fast-growing breeder sires had lower plasma thyroid hormone, reduced proportional lung weights, low arterial pO2 and high arterial pCO2 pressures compared with the slower-growing lines. 7. In conclusion, ascites incidence was associated with lower heat production per metabolic body weight and therefore a lower oxygen requirement per metabolic weight. 相似文献
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小尾寒羊和大尾寒羊能量与蛋白质代谢规律研究 总被引：4，自引：0，他引：4
选用小尾寒羊和大尾寒羊200只．分妊娠期、泌乳期、哺乳期和生长期4个不同生理阶段．系统研究了蛋白质和能量代谢规律。研究过程采用了饲养对比试验8次．消化代谢试验16次．低氮日粮平衡试验4次，气体能量代谢试验6次．比较屠宰试验4次，并采用瘤胃瘘管技术、血液生理生化指标测定等技术。制定出小尾寒羊和大尾寒羊的能量维持需要、各级有效能转化效率、畜体总产热和绝食代谢产热等基础代谢参数89个．粗蛋白质和可消化粗蛋白质维持需要、不同生理状态和生产水平下的粗蛋白质、可消化粗蛋白质生产需要、以及内源尿氮和代谢粪氮等蛋白质代谢参数58个。 相似文献
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It was the objective of this study to quantify heat production across ages of Rambouillet and Finnsheep ewes and to evaluate the previous hypothesis that breed differences can be accounted for by scaling for proportion of mature body weight. Seventy-two Finnsheep and 55 Rambouillet ewes were sampled. Heat production was estimated based on individual animal gaseous exchange, which was determined from 55 through 71 h of the feed restriction. Heat production per unit BW decreased as sheep aged, and the breed-specific functions fit the data better than the pooled functions. The rate of decrease in heat production was greater in Finnsheep ewes until 37 wk of age. The rate of growth of Rambouillet ewes was greater than that of Finnsheep ewes over the first 52 wk of age, and Rambouillet ewes reached 95% of their mature BW at an earlier age (71 wk) than did Finnsheep ewes (113 wk). At any given age, Rambouillet ewes had achieved a greater proportion of their mature BW and had a lower heat production per unit BW than Finnsheep ewes. This study demonstrated the necessity of accounting for both age and breed when estimating metabolic rate in sheep. Furthermore, this study suggested that breed and age differences in metabolic rate could be accounted for by scaling for proportion of mature BW and that daily heat production per unit BW (kcal/kg) of Finnsheep, Rambouillet, Suffolk, and Texel ewes can be described by the function /(BW, matBW) = 59.5e(-0.797(Bw/matBw)), where BW = body weight and matBW = mature body weight. 相似文献
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1. From each of two populations of White Leghorn laying hens, 6 'efficient' and 6 'inefficient' hens were used in energy metabolism studies involving indirect calorimetry with activity measurement. 2. Hens classified as efficient or inefficient with respect to residual food consumption had comparable body weight and production. 3. Efficient and inefficient hens showed similar energy metabolisability, cloacal temperature, shank dimension and egg composition. 4. However, efficient hens produced less heat; activity-related heat production accounted for 29 to 54% of the difference in total heat production between efficient and inefficient hens. 5. Plumage quality also explained some of the difference in heat production, but to a lesser extent (14 to 19%). 6. Adjustment for heat increment of production changed the heat production difference slightly (-5 to 1%). 7. What was finally left unexplained (100 - 54 - 14 + 5 = 37% to 100 - 29 - 19 - 1 = 51%) was of the same magnitude as activity-related HP and is discussed in relation to basal metabolic rate. 相似文献
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The relationship between starvation heat production (SHP) in kJ/d and body weight (W) in kg for the domestic fowl was examined by compiling calorimetric data on 78 immature and 222 mature fowls. Linear regression analyses were performed after transformation of the data to a logarithmic scale (base = 10). The derived relationship (re-transformed) for mature birds was found to be: SHP = 406 W0.602 The weight exponent (b) was significantly (P less than 0.01) different to the value of 0.75 normally used for mature birds. 相似文献
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奶牛热应激综合征是指奶牛受到超过本身体温调节能力的高温刺激而产生的非特异性防御反应。奶牛发生热应激后会激活体内的下丘脑-垂体-肾上腺轴,改变机体的神经内分泌调节网络,引起奶牛体内皮质醇激素和多种激素水平变化,协同作用于机体以抵抗热应激对自身的影响;此外,热应激奶牛采食量和消化率普遍降低,营养物质摄入不足,机体处于能量负平衡状态。在这种状态下,奶牛会通过增加体内糖、脂肪和蛋白质的代谢来为机体提供能量从而缓解热应激。然而,严重热应激会导致奶牛代谢功能紊乱及免疫系统损伤,最终导致奶牛消化率、产奶量、繁殖率下降,而疾病易感风险性增加,从而影响奶牛生产的经济效益,给畜牧业带来巨大的经济损失。目前,关于奶牛热应激的研究较多,且多集中于产奶性能和繁殖性能等方面,而有关生理和免疫机能的研究报道较少。作者阐述了奶牛发生热应激时皮质醇激素的变化和调节、三大代谢过程的改变及免疫细胞和相关细胞因子的表达分泌等过程,旨在更加深入地了解热应激对奶牛生理状态及免疫功能的影响,从而为奶牛热应激综合征的防控、诊断和治疗提供理论依据。 相似文献
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An experiment was carried out to verify the relationship between the heat production associated with food intake and environmental temperature. Four laying hens were trained to eat two meals per day and were kept under artificial illumination with dark, dim and light periods. 2. Metabolic heat production was measured using two open-circuit respiratory chambers. Abdominal temperatures were measured, using thermocouples, at environmental temperatures of 12, 16, 20, 24, 28, 32 and 36 degrees C and at food intakes of 90, 60, 30 and 0 g/d. 3. The rate of heat production was dependent on both environmental temperature and food intake. Increasing environmental temperature resulted in a decrease in total metabolic rate at any food intake, indicating that heat production associated with food intake was not directly linked with thermoregulation at low environmental temperatures. 4. Abdominal temperature varied little with either food intake or environmental temperature below 28 degrees C. Above 28 degrees C, abdominal temperature increased with both environmental temperature and quantity of food, indicating that the heat production associated with food intake adds to the heat load at high environmental temperatures. 5. Both heat production and abdominal temperature declined with decreasing light intensity and increased before feeding time. These effects were considered to result from changes in physical activity. 相似文献
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试验旨在探讨低温环境对生长猪气体能量代谢的影响。选用12头(30±0.5)kg健康的杜×长×大三元杂交去势公猪,随机分为对照组(23℃)和试验组(13℃),每组6个重复,每个重复1头,预试期3d,试验期19d。在预试期,对照组和试验组猪舍温度由18℃以每小时1℃缓慢调至23℃和13℃。试验利用间接呼吸测热法与消化代谢试验相结合对生长猪进行气体能量测定。结果表明:试验组CO_2产生量和O_2消耗量分别较对照组极显著增加23.25%和26.23%(P0.01);试验组代谢体重CO_2产生量和代谢体重O_2消耗量较对照组分别极显著增加28.66%和31.67%(P0.01);试验组平均每天产热量和代谢产热量较对照组分别极显著增加25.52%和31.08%(P0.01)。综上所述,生长猪在低温环境的气体能量代谢显著增加,CO_2产生量和O_2消耗量均显著增加。 相似文献
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7 experiments with 6 chickens each (origin Tetra B) in the live weight range between greater than 100 and less than 300 g and up to 1800 g were carried out at environmental temperatures (ET) of 35, 30, 25 (2 experiments) 20 (2 experiments) and 15 degrees C. In the course of each experiment the chickens alternatively received feed mixtures containing 20 and 40% crude protein (3 animals/variant) for maintenance and weight gain (semi ad libitum). Energy metabolism was measured according to indirect calorimetry over a total of 645 metabolism periods. In the temperature range studied there was no compensation between thermoregulatory heat and heat from other metabolic processes. The partial utilization of metabolizable energy for energy retention in the body was independent of ET and remained in the limits between 71 and 73%. Energy utilization was dependent on the protein content of the feed. It decreased from 75 to 69% with the increase of the protein content from 20 to 40%. Energy requirement for protein retention varied between 1.67 and 1.89 kJ metabolizable energy/kJ and was independent of ET. Energy requirement (metabolizable energy) for the maintenance of the energy balance was independent of the protein content of the feed. It increased from 433 kJ/kg LW0.75.d at 35 degrees C to 693 kJ/kg LW0.75.d at 15 degrees C ET. The relationship between heat production and ET is parabolic. The thermoneutral temperature decreased from 35 to 25 degrees C in the course of development. In the live weight range of 300-500 g thermoregulatory heat production had its maximum with 19 kJ/kg LW0.75.d.K and decreased in the further development to 10-13 kJ/kg LW0.75.d.K. 相似文献