冷季补饲精料对牦牛繁殖性能和生长性能的影响

试验旨在探究冷季补饲精料对怀孕牦牛繁殖性能、生长期牦牛生长性能的影响。试验一选用6岁左右、健康无病的经产怀孕麦洼牦牛10头,随机分为2组(5头/组),即对照组(全放牧)和精料组(放牧+精料补饲料400g/d)。试验二选用2岁左右、健康无病的生长期麦洼牦牛21头,随机分为3组(7头/组),即对照组(全放牧)、玉米组(放牧+补饲玉米500 g/d)和玉米菜粕组(放牧+补饲玉米菜粕500 g/d,各50%)。结果表明:试验一,精料组犊牦牛初生重比对照组极显著提高47.48%(P<0.01);试验二,对照组生长牦牛体重下降9.25 kg,补饲玉米组和玉米菜粕组生长期牦牛分别增重12.38 kg和2.33 kg,均极显著高于对照组(P<0.01),而且玉米组生长牦牛增重极显著高于玉米菜粕组(P<0.01)。结果提示,冷季给予怀孕牦牛补饲精料可提高犊牦牛初生重;冷季生长牦牛补充精料有助于提高生长性能,同时补饲能量饲料(玉米)的效果高于蛋白饲料(菜粕)。     

冷季补饲精料对牦牛繁殖性能和生长性能的影响探讨

目的:研究探讨冷季补饲精料对牦牛繁殖性能和生长性能的影响。方法:A试验选用8头分娩期相近、7岁左右的牦牛,平均随机分为精饲组和对照组。精饲组采用放牧与精料补饲400 g/d方式,对照组采用常规全放牧。B试验选用18头健康无病、2岁左右的牦牛,随机分成玉米组、玉米菜粕组和对照组。对照组采用全放牧,玉米组采用放牧和补饲玉米500 g/d,玉米菜粕组采用放牧和补饲500 g/d玉米与菜粕(各50%)。结果:A试验精饲组初生牛犊的初生重比对照组的初生重比率增加47.48%(P0.01),具有明显优势;B试验对照组牦牛减重9.25 kg;玉米组和玉米菜粕组各自增重12.38 kg、2.33 kg。相较于对照组,玉米组与玉米菜粕组有明显的增重优势(P0.01),而且玉米组的增重还明显高于玉米菜粕组(P0.01)。结论:相较于常规全放牧的方式喂养牦牛,冷季对牦牛进行补饲精料,提高了牦牛的生长、繁殖性能,还可以使怀孕牦牛生产的犊牦牛初生重增加。而在精料中能量饲料(玉米)比高蛋白饲料(菜粕)喂养效果更佳。     

补饲,放牧,微贮秸秆对6月龄藏羊羯羔增重效果的观察

应用精料补饲、放牧、微贮秸秆三种饲喂方法 ,对 6月龄藏羊羯羔 6 0天的增重放牧进行了比较。结果 :放牧组平均增重 10 .2 kg,日增重 170 g;精料补饲组增重9.5 kg,日增重 15 8g;微贮秸秆组增重 6 .3kg,日增重 10 5 g。经方差分析 ,放牧组与精料补饲组差异不显著 ,放牧组和精料组与微贮组差异极显著。精料补饲组屠宰率比放牧组和微贮组分别高 3.37和 3.5 9个百分点     

精料补饲水平对暖季放牧牦牛生长性能、血清生化指标及养殖收益的影响

本研究旨在探讨精料补饲水平对暖季放牧牦牛生长性能、血清生化指标及养殖收益的影响,以期为青藏高原暖季放牧牦牛补饲提供理论依据。选取体重相近[(123.96±7.43) kg]、体况良好的公牦牛48头,随机分为4组(每组12头)。以放牧为对照组,3个补饲组分别补饲0.5、1.5和2.5 kg·d^-1精料。预试期10 d,正试期60 d。结果表明:1)补饲精料对暖季放牧牦牛平均日增重(average daily gain, ADG)有显著影响(P <0.05),其中2.5 kg·d^-1补饲组平均日增重最高,比对照组增加了286.42%。2)与对照组相比,1.5和2.5 kg·d^-1补饲组显著提高了血清葡萄糖(glucose,GLU)、总蛋白(total protein, TP)、和谷草转氨酶(aspartate aminotransferase, AST)的含量(P <0.05),而2.5 kg·d^-1补饲组血清尿素氮(urea nitrogen, UN)的含量显著降低(P <0.05)...     

夏季补饲对放牧条件下泌乳牦牛生产性能及血液生理、生化、抗氧化指标的影响

本试验旨在研究夏季补饲对放牧条件下泌乳牦牛生产性能及血液生理、生化、抗氧化指标的影响。试验采用2×2双因子设计,选用24头体重[(218.0±19.5) kg]相近的健康带犊泌乳牦牛,随机分为4个组(每组6头),即自然放牧组(NG组)、氨基酸补饲组[SA组,补饲15 g/(d·头)过瘤胃赖氨酸+5 g/(d·头)过瘤胃蛋氨酸]、精料补饲组[SC组,补饲1.2 kg/(d·头)精料]和氨基酸+精料补饲组[SAC组,补饲15 g/(d·头)过瘤胃赖氨酸+5 g/(d·头)过瘤胃蛋氨酸+1.2 kg/(d·头)精料]。预试期9 d,正试期23 d。结果表明:1)补饲氨基酸、精料及两者交互作用对泌乳牦牛的总产奶量和平均日产奶量无显著影响(P0.10)。与NG组相比,补饲精料显著提高了泌乳牦牛的平均日增重(P0.05),而补饲氨基酸对泌乳牦牛的平均日增重无显著影响(P0.10)。与NG组相比,补饲氨基酸具有提高犊牛的平均日增重的趋势(P=0.098),补饲精料及氨基酸和精料交互作用显著提高了犊牛的平均日增重(P 0.05)。2)与NG组相比,补饲氨基酸具有增加泌乳牦牛血液平均红细胞蛋白量(P=0.089)和降低平均血小板体积(P=0.084)的趋势。补饲氨基酸、精料及两者交互作用对泌乳牦牛其余血液生理指标无显著影响(P0.10)。3)补饲氨基酸、精料及两者交互作用对泌乳牦牛血清生化和抗氧化指标无显著影响(P0.10)。由此可见,夏季补饲精料+氨基酸能够同时促进放牧条件下泌乳母牦牛和犊牛的平均日增重。     

冷季补饲对欧拉型藏羊生产性能的影响

试验旨在研究冷季精料补饲量对欧拉型藏羊生长性能的影响。选择9月龄欧拉型藏羊羯羊40只,随机分为4组,每组10只,Ⅰ组(放牧)、Ⅱ组(放牧+0.1 kg混合精料)、Ⅲ组(放牧+0.2 kg混合精料)、Ⅳ组(放牧+0.3 kg混合精料),试验期210 d(2017年10月中旬—2018年5月中旬)。每30天测定试验羊体重、体尺及其所在草场牧草营养成分。结果表明:(1)牧草干物质、中性洗涤纤维含量均随枯草期的延长呈上升趋势,代谢能、粗蛋白、粗脂肪含量随着枯草季节的延长逐月下降。(2)所有试验动物平均日增重10—12月份增加,1—4月份增重放缓(其中I组动物平均日增重为负值),4—5月份动物平均日增重缓慢回升;整个试验期平均日增重为Ⅳ组Ⅲ组Ⅱ组Ⅰ组(P0.05)。(3)至试验结束各处理组试验动物体尺(除胸围外)变化均为Ⅳ组Ⅲ组Ⅱ组Ⅰ组。(4)经济效益分析表明,随着精料补饲量的加大,枯草期羊的平均日增重、精饲料成本和利润均在增大。整个试验期,IV组每只羊利润较I组高出约1倍(77.10元);III组每只羊的利润较I组增加45.90元。结论:随枯草季节的延长,牧草营养成分明显降低,4月份牧草营养成分降至一年中最低水平;冷季补饲精饲料,可显著增加欧拉型藏羊过冬度春的能力,增加经济效益;在该试验条件下,冷季精料补饲量越高,羊的日增重越高,经济效益越好。     

补饲复合营养预混剂对灌丛放牧山羊育肥的效果观察研究

选用 6 0只罗甸本地黑山羊 ,随机分成 3组 ,在放牧条件下 ,第 1组补饲复合营养预混剂 ,第 2组补饲精饲料 ,第 3组为对照 ,进行为期 6 0d的对比试验。试验结果表明 :在 6 0d的试验期间内 ,预混剂组羊总增重 10 5.6kg ,精料组羊总增重 6 0 .0kg ,对照组羊总增重 56 .0kg。试验期间 ,预混剂组头均日增重 88g ,比精料组增重的 58.33g ,提高了 2 4 .98% (P <0 .0 5) ,比对照组增重的 4 6 .6 7g提高了88.55% (P <0 .0 5)。预混剂组比精料组和对照组平均每只山羊每日净增纯利 0 .16元和 0 .18元。表明在灌丛中放牧的山羊使用复合营养预混剂对体重的增加有明显的效果。     

冬春季节补饲精料对BMY牛育肥性能的影响

[目的]冬春枯草季节,为研究在不同饲养水平下对6-9月龄BMY公牛增重性能的影响。[方法]以6-9月龄BMY公牛为育肥对象,5种育肥方式分别为：对照组全放牧不设补饲;试验1组采用放牧＋补饲1.0 kg精料;试验2组采用全舍饲（粗饲料自由采食,补饲1.0 kg/d精料）;试验3组采用全舍饲（粗饲料自由采食,补饲2.0 kg/d精料）;试验4组采用全舍饲（粗饲料自由采食,补饲3.0 kg/d精料）。[结果]表明：6-9月龄BMY公牛在冬季全放牧条件下育肥,体重不会增加反而会减少,平均日增重（ADG）为-178 g;在冬季放牧＋补饲1.0 kg精料的情况下,ADG为395 g;在舍饲＋1.0 kg精料、舍饲＋2.0 kg精料和舍饲＋3.0 kg精料的情况下,ADG分别达600 g7、28 g和1,023 g,补饲效果差异极显著（P〈0.01）,表明BMY牛在舍饲条件下生长更快,可获得更高的ADG。随着补饲日粮营养水平的提高,随着BMY牛日粮干物质采食量增加,说明补饲精料有利于粗饲料的摄入,从而增加ADG。[结论]冬春枯草季节补饲精料,无论放牧还是舍饲,6-9月龄BMY公牛均有较好的ADG,以舍饲加补饲精料的增重效果最为明显,可获得理想的经济收益。     

补饲非蛋白氮补充料对放牧牛群生产性能的影响

本试验旨在研究补饲非蛋白氮（NPN）补充料对放牧牛群生产性能的影响。试验在春末夏初放牧前,选择30头9~10月龄、体重150~170 kg的中国西门塔尔太行类群小公牛,分为对照组、试验1组和试验2组,进行放牧加补饲试验。试验1组日补饲玉米粉1.0 kg;试验2组在试验1组的基础上增补NPN补充料0.25 kg。进行了为期100 d的放牧补饲效果试验。结果表明,对照组、试验1组、试验2组日增重分别为0.622、0.839和1.051 kg。试验1组比对照组日增重提高217 g;试验2组比对照组和试验1组日增重分别提高429和212 g。3组间增重差异显著。因此,北方山坡草地放牧牛群补饲少量精料效果明显,同时,补喂少量NPN补充料经济效益更为显著。     

冷季补饲精料对放牧牦牛生长性能、养分消化率和血清生化指标的影响

为研究冷季补饲精料对放牧牦牛生长性能、表观消化率和血清生化指标的影响,试验选取健康麦洼牦牛132头,按年龄和体重相近的原则随机分为2组,即对照组和补饲组,每组66头牦牛,补饲组归牧后补饲精料(1 kg/d·头),对照组只放牧。试验期为60 d。结果表明:(1)与对照组相比,补饲组牦牛的总增重和平均日增重显著提高(P 0.05),掉膘降低41.42%,补饲组成年牦牛、犊牦牛的总增重和平均日增重显著高于对照组(P 0.05),成年牦牛掉膘降低55.14%,犊牦牛掉膘降低57.31%;(2)补饲组牦牛粗蛋白质、中性洗涤纤维、酸性洗涤纤维的表观消化率显著高于对照组(P 0.05),分别提高7.56%、9.86%、8.45%,补饲组成年牦牛、犊牦牛酸性洗涤纤维的表观消化率显著高于对照组(P 0.05),犊牦牛提高10.52%,成年牦牛提高10.69%;(3)补饲组与对照组放牧牦牛血清中谷丙转氨酶、谷草转氨酶活性和总蛋白、尿素、葡萄糖、胆固醇、甘油三酯及肌酸激酶含量无显著差异(P 0.05),补饲组成年牦牛血清中总蛋白含量显著高于对照组(P 0.05),提高24.41%。由此可见,冷季补饲精料有助于提高放牧牦牛生长性能和对营养物质的消化率,有利于牦牛冷季保镖,且对犊牦牛的效果优于青年牦牛。     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.     

Prevalence of gastric lesions in racing Alaskan sled dogs

Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.     

Chemotaxis of macrophage in inflammation

Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.     

Serum biochemical values and mineral element contents of tissues in yaks

Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein