冷季补饲对藏羊消化道消化酶活性及表观消化率的影响

本试验旨在研究冷季补饲尿素-糖蜜型舔砖或精料2种营养补充方式对藏羊生长性能、消化道消化酶活性及表观消化率的影响。选择1.5岁藏系绵羊母羊18只,随机分为3组,每组6只羊。其中对照(CON)组自由采食燕麦干草,尿素-糖蜜型舔砖补饲(BS)组在CON组基础上自由舔食尿素-糖蜜型舔砖,精料补饲(CS)组在CON组基础上补饲精料200 g/(只·d)。60 d饲养试验结束后,进行4 d消化试验,最后进行屠宰试验。结果表明:1)消化能和粗蛋白质平均日采食量CS组和BS组分别比CON组多29.68%、40.00%和11.37%、20.00%(P0.05);2)CS组和BS组平均日增重(ADG)分别是CON组的3.22和1.98倍(P0.05);3)与CON组相比,补饲显著提高了血清葡萄糖(GLU)、总胆固醇(CHO)、甘油三酯(TG)、总蛋白(TP)、球蛋白(GLB)和白蛋白(ALB)浓度(P0.05);4)与CON组相比,补饲显著提高了干物质(DM)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)表观消化率(P0.05),且CS组高于BS组(P0.05);5)与CON组相比,补饲精料和尿素-糖蜜型舔砖均显著提高了瘤胃液中木聚糖酶、蛋白水解酶和氨基肽酶活性(P0.05),且CS组显著高于BS组(P0.05),补饲精料还显著提高了小肠各段黏膜中α淀粉酶、胰蛋白酶活性(P0.05)。结果提示,在冷季通过补饲尿素-糖蜜型舔砖或精料,均可显著增加藏羊对能量、蛋白质及微量元素的采食量,显著增加消化道消化酶活性,从而提高营养物质表观消化率和藏羊的生长性能;在本试验条件下,冷季对能量和蛋白质的补充摄入水平越高,藏羊的日增重越高。     

冷季补饲对藏羊小肠形态发育及营养物质转运载体基因表达量的影响

本试验旨在研究冷季补饲精料或尿素-糖蜜型舔砖对藏羊小肠组织形态发育及营养物质转运载体基因表达量的影响。选择1.5岁、体重((29.4±1.79)kg)相近的健康藏系绵羊母羊18头,随机分为对照组(CON组)、尿素-糖蜜型舔砖补饲组(BS组)和精料补饲组(CS组)。CON组自由采食燕麦干草,BS组在CON组基础上自由舔食尿素-糖蜜型舔砖,CS组在CON组基础上补饲精料200g·只-1·d-1。进行60d的饲养试验后,对全部试验藏羊进行屠宰,采集小肠各段组织,通过制作组织切片及荧光定量PCR,测定小肠组织形态发育和营养物质转运载体基因表达量。结果表明:(1)补饲精料或舔砖均显著提高了藏羊消化能和粗蛋白质摄入量(P0.05),且CS组显著高于BS组(P0.05);(2)补饲精料或舔砖均显著提高了藏羊十二指肠、空肠及回肠绒毛宽度(P0.05),且CS组均显著大于BS组(P0.05),补饲精料还显著提高了十二指肠和回肠绒毛高度(P0.05),显著降低了空肠和回肠隐窝深度(P0.05);(3)胰岛素样生长因子结合蛋白5(Insulin-like growth factor binding protein,IGFBP5)mRNA表达量在十二指肠和空肠黏膜中CS和BS组均显著高于CON组(P0.05),且CS组显著高于BS组(P0.05),在回肠黏膜中CS组显著高于BS和CON组(P0.05);(4)十二指肠黏膜中L型氨基酸转运载体1(L-type amino acid transporter 1,LAT1)、阳离子氨基酸转运载体1(Cationic amino acid transporters 1,CAT1)、小肽转运载体1(Peptides transporter 1,pepT1)、钠依赖型葡萄糖转运载体1(Na+-dependent glucose co-transporter 1,SGLT1)及促葡萄糖转运载体2(Facilitative glucose transporter 2,GLUT2)mRNA表达量CS组显著高于BS和CON组(P0.05),空肠黏膜中CAT1、pepT1mRNA表达量和回肠黏膜中CAT1、LAT1、SGLT1及GLUT2mRNA表达量,BS组显著高于CS和CON组(P0.05)。以上结果表明,冷季补饲精料或尿素-糖蜜型舔砖均增加了藏羊对能量和蛋白质等营养物质的摄入量,促进了小肠组织形态发育,补饲精料提高了十二指肠黏膜中氨基酸、小肽及葡萄糖转运载体基因mRNA的表达量,而补饲尿素-糖蜜型舔砖提高了其在空肠和回肠黏膜中的表达量。     

冷季放牧绵羊补饲尿素-糖蜜营养舔砖的效果

对冷季放牧绵羊补饲尿素-糖蜜营养舔砖效果进行了分析。选用蒙古系绵羊后备母羊60只,随机分为3 组,在全放牧条件下,试验1 组每天只均补饲整粒玉米Zea mays 100 g和尿素-糖蜜营养舔砖200 g,试验2组每天只均补饲整粒玉米300 g,3组（纯放牧组）不补饲。结果表明,试验1组比纯放牧组和试验2组日增体质量分别提高205.65 g(P <0.01)和58.87 g(P<0.01),头均收入分别比纯放牧组和试验2组增加41.99元和21.14元。     

补饲尿素糖蜜舔砖对冬季育肥羊增重的影响

在冬季农村传统养殖条件下，对5～6月龄育肥青海半细毛羊进行补饲尿素糖蜜舔砖试验，平均每只舔食量为151g／d，经30d短期育肥，日增重为245g，比仅喂秸秆育肥时（134．0g）提高82．8％（P〈0．05），每只平均盈利增加25．03元，经济效益提高54．57％。     

采用PCR-DGGE技术对放牧羊补饲糖蜜尿素舔砖后细菌种群结构的分析

为了研究补饲糖蜜尿素舔砖对放牧羊瘤胃中细菌种群结构随时间变化的规律,试验采用基于16S DNA的PCR变性梯度凝胶电泳(DGGE)技术,在放牧羊舔食舔砖的不同时间点取样,进行瘤胃液的DGGE分析。结果表明:舔食糖蜜尿素舔砖后放牧羊瘤胃细菌主要以拟杆菌门、硬壁菌门为主。在舔食15 d后瘤胃细菌多样性显著增加,舔食30 d后瘤胃细菌多样性达到最高。糖蜜-尿素对瘤胃微生物种群具有明显的筛选作用,舔食前以Capnocytophaga canimorsus为优势菌群,舔食一段时间后各菌群或出现或消失,呈动态变化和定植过程;30 d后瘤胃种群结构基本保持稳定,Prevotella ruminicola Bryant处于优势地位。说明舔食舔砖前后细菌种群结构存在明显差异,舔砖可明显增加瘤胃微生物多样性。     

不同尿素水平的糖蜜舔砖对黑山羊增重的影响

选用生长发育良好、健康无病的湘东黑山羊21只,随机分成3组,其中A组为对照组,饲喂基础日粮;B组和C组是试验组,分别在饲喂基础日粮的基础上,补饲尿素含量为7%和10%的尿素糖蜜舔砖,做尿素糖蜜舔砖对山羊增重效果的试验。结果表明,在为期1个月的试验中,补饲舔砖对山羊增重效果显著(P<0.05),试验B、C组分别每只羊比A组平均多增重1.2和2.1kg,净收益高8.34和17.13元。此外,补饲尿素糖蜜舔砖的羊只较对照组被毛光泽、食欲旺盛、精神好和异嗜现象明显减少。     

补饲尿素糖蜜型饲料舔砖对杂交公牛生长效果的影响

选择西黄杂(西门塔尔×本地黄牛)公牛30头,分成2组,试验组补饲50d尿素糖蜜型饲料舔砖,对照组不作任何处理,其他饲养管理条件完全相同。结果试验组平均日增重480g,对照组296g。试验组比对照日增重提高62.2%,差异极显著(P<0.01)。试验表明尿素糖蜜型饲料舔砖对促进杂交公牛的生长发育,提高其经济效益具有显著的作用。     

补饲糖蜜尿素舔砖对水牛增重性能的影响

在冬春季节 ,饲养状况差的情况下 ,利用 14头育成水牛进行了为期 6 0天的补饲糖蜜尿素舔砖对比饲养试验。结果表明 :补饲舔砖的水牛平均日增重为 30 8± 5 6g ,比对照组 113± 6 3g的日增重提高 195g,差异显著 (P <0 .0 1) ;试验组干物质采食量比对照组提高 13 6 % ;试验期间补饲舔砖的试验组平均每头水牛比对照组增加毛利收入 2 1 6元 ,日头均增加毛利收入 0 36元。说明补饲糖蜜尿素舔砖能明显提高水牛的增重性能 ,经济效益显著     

补饲营养舔砖对肉牛生长性能的影响

试验旨在研究补饲营养舔砖对肉牛生长性能和经济效益的影响。试验采用单因子完全试验设计,将20月龄左右,体重(427±24)kg的90头科尔沁黄牛分成3组,每组30头。试验1组,预饲期补饲糖蜜舔砖,正式试验期补饲碱微舔砖;试验2组,预饲期和正式期均补饲碱微舔砖;对照组不补饲任何舔砖,其他饲养模式与2个试验组相同。试验共持续194 d,其中预饲期为14 d,正式试验期为180 d;每隔30 d称空腹体重和采集饲料样,出栏时计算出经济效益。结果表明:试验1组的平均干物质采食量比对照组提高了5%,并差异显著(P0.05);试验2组的平均干物质采食量比对照组提高了4%,但差异不显著(P0.05);2个试验组间平均干物质采食量差异不显著(P0.05)。试验1组与试验2组的平均日增重比对照组分别提高了11.20%和8%,但试验组之间没有显著差异(P0.05)。试验1组比对照组每头每天多盈利1.20元,试验2组比对照组每头每天多盈利0.55元。因此肉牛育肥过程中合理补饲营养舔砖能够促进其生长,并提高经济效益。     

山羊尿素舔砖不同添加水平的效果试验

本试验选取21头10月龄、体重26kg左右的湘东黑山羊,随机分成3组,其中A组为对照组,饲喂基础日粮,B组和C组为试验组,分别在饲喂基础日粮的基础上,补饲尿素含量为7%和10%的尿素糖蜜舔砖,以研究尿素糖蜜舔砖对山羊增重效果的影响。结果表明:补饲尿素糖蜜舔砖后,湘东黑山羊营养状况大大改善,增重速度得到不同程度的提高。补饲舔砖的B、C试验组日增重分别为0.12kg和0.15kg,比对照组分别高50%和87.5%,试验C组比试验B组高2 5%,经方差分析差异及显著(P<0.01)。试验B、C组中每只羊比对照组分别多收入8.34元和17.13元。从而也得出10%尿素添加比7%尿素添加的舔砖补饲山羊的效果要好。     

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