吉他霉素在肉鸡饲养中的应用

将平均出生体重41g±1.94g的肉雏鸡按饲养试验随机分成2组,每组设2个重复,一组做对照组,日粮中不添加吉他霉素;另一组为试验组,日粮中添加吉他霉素100mg/kg。分2个阶段(0～3周龄、4～6周龄)进行肉鸡日粮中添加吉他霉素对提高肉鸡增重和提高饲料效率的试验研究,并观察吉他霉素对预防肉鸡呼吸道和消化道疾病及提高肉鸡成活率的作用效应。试验结果表明,在0～3周龄肉鸡日粮中每千克添加100mg吉他霉素,试验组比对照组多增重89.1g,可提高阶段增重14.6%(P<0.05),增重效果显著;在肉鸡4～6周龄内试验组比对照组多增重135.7g,可提高阶段增重9.9%(P<0.05),增重效果显著;全期试验组比对照组多增重224.8g,可提高增重11.40%(P<0.05),增重效果显著。在饲料消耗方面,在肉鸡0～3周龄期间,试验组比对照组多采食18.1g,提高采食量2%(P>0.05),饲料消耗差异不显著;在4～6周龄期间,试验组比对照组多采食46.2g,提高采食量1.5%(P>0.05),饲料消耗差异不显著;全期试验组比对照组平均每只多采食64.3g,提高采食量1.6%,饲料消耗差异不显著。在饲料报酬方面,吉他霉素可提高肉鸡0～3周龄饲料转化率12.1%;提高肉鸡4～6周龄饲料转化率8.4%;全期提高饲料转化率9.7%。这说明吉他霉素有明显的促进肉鸡生长,提高饲料转化率的作用;同时,吉他霉素在一定程度上可有效预防呼吸道和肠道疾病,提高鸡只的成活率。     

地肤草粉喂猪效果及其对血相的影响

10头 56kg左右的长白×本地杂交猪 ,随机平分为 2组 ,即对照组与试验组。对照组喂玉米 豆粕 鱼粉型基础日粮 ;试验组用地肤草粉代替 1 0 %的基础日粮。结果表明 ,平均日增重对照组与试验组分别为 664 4g和 648 9g ;料重比分别为 3 2 5和 3 37,差异均不显著 (P >0 0 5) ,但试验组每千克增重饲料成本下降 4 36%。血相检测结果表明 ,试验组供试猪血相指标变化在正常生理值范围内。猪日粮中使用 1 0 %的地肤草粉是可行的     

低能量日粮中添加非淀粉多糖酶对仔猪生长性能的影响

以杜×长×大杂交仔猪120头为研究对象,随机分成对照组Ⅰ(饲喂基础日粮)、对照组Ⅱ(基础日粮中减少292kJ/kg消化能)和试验组(基础日粮中减少292kJ/kg消化能,添加500g/t罗酶宝)3个处理组,研究低能量的玉米-豆粕型日粮中添加非淀粉多糖酶(木聚糖酶和β-葡聚糖酶)对仔猪生长性能和消化性能的影响。结果表明:与对照组Ⅱ相比,试验组仔猪的日增重提高6.53%(P<0.05),饲料转化率提高7.25%(P<0.05),粗蛋白质的表观消化率提高5.76%(P<0.05);与对照组Ⅰ相比,试验组仔猪在日增重、饲料转化率、营养物质表观消化率方面有一定的提高,但差异不显著(P>0.05),说明在日粮中添加500g/t罗酶宝与增加292kJ/kg消化能的效果相当。     

复合酶制剂对生长肥育猪的饲喂效果

选用体重27kg的杜长大三元杂交生长肥育猪42头,随机分成对照组和试验组,每组3个重复组,对照组饲喂基础日粮,试验组饲喂基础日粮+0.01%复合酶制剂,试验期32d。试验结果表明:复合酶制剂可将猪平均日增重提高0.057kg(P<0.05);平均日采食量降低0.072kg,饲料增重比降低13.31%;每千克增重饲料成本降低0.605元,经济效益提高了12.62%。     

那拉霉素对生长猪的饲养效果试验

在相同营养水平下,对照组不添加任何药物添加剂,试验组添加10%那拉霉素20mg/kg的基础日粮,对照组与试验组分别饲喂21头杜·长·大三元杂交猪,试验组和对照组平均始重分别为25.3kg、25.4kg,平均末重分别为61.2kg和57.49kg,试验组和对照组平均日增重分别为726.3g、641.8g,料重比分别为2.771和2.983。试验表明生长猪日粮中添加那拉霉素比对照组日增重和饲料利用率显著提高。     

复合酶制剂对生长肥育猪的饲喂效果

选用体重27 kg的杜长大三元杂交生长肥育猪42头,随机分成对照组和试验组,每组3个重复组,对照组饲喂基础日粮,试验组饲喂基础日粮+0.01%复合酶制剂,试验期32 d.试验结果表明复合酶制剂可将猪平均日增重提高0.057 kg(P<0.05);平均日采食量降低0.072 kg,饲料增重比降低13.31%;每千克增重饲料成本降低0.605元,经济效益提高了12.62%.     

鲁梅克斯K-1杂交酸模替代大豆后对生长育肥猪的饲喂效果试验

选用平均体重25kg左右的生长育肥猪(长白×杜洛克×互助猪)30头,按性别搭配随机分为对照组和试验组,对照组只喂基础日粮,试验组喂以用19％鲁梅克斯K-1杂交酸模干品完全替代19％大豆后配以其它组分不变的对照组日粮,通过饲喂试验,结果表明,试验组日增重比对照组降低1.79％,个体增重差异不显著(P>0.05),试验组比对照组每kg增重饲料成本降低26.35％,每kg增重饲料成本差异显著(P<0.05)。     

不同精粗比饲料对宁夏滩羊育肥效果试验

本试验对集约化养殖过程中滩羊的不同精粗比饲料对滩羊育肥效果的影响进行研究,试验结果显示:平均日增重试验组B(162.86g)显著高于试验组A(141.14g)(P0.05),试验组B日增重极显著高于对照组(113.86g)(P0.01),饲料转化率试验组B最低为6.02∶1;胴体重试验组B(18.53kg)显著高于试验组A(17.02kg)和对照组(15.03kg)(P0.05),试验组B比对照组高3.50kg,试验组B的屠宰率为51.8%;试验组B的经济效益比试验组A提高96.97元/头。结果表明,精粗比为3∶7的饲料育肥集约化对宁夏滩羊经济效益提高显著,值得大力推广。     

猪肠道微生物对育肥猪增重的影响

为了掌握猪肠道微生物对育肥猪增重效果的影响,为提高育肥猪增重提供有效的方法,为猪肠道微生物在育肥猪饲料添加剂中的推广应用提供参考依据。将60头育肥猪随机分成2组(对照组和试验组),对照组饲喂基础日粮,试验组在基础日粮中添加0.1%的肠道微生物。试验结果显示:与对照组相比,试验组的平均末体重提高了4.41 kg(P<0.05),平均日增重提高了70g(P<0.05),料重比降低了0.08(P<0.05),表明猪肠道微生物可显著提高育肥猪的增重。     

禽全能中草药添加剂对芦花雏鸡生长性能及经济效益的影响

本试验选取1日龄健康、体重相近的芦花雏鸡600只(公母各半),随机分成2组,每组4个重复,每个重复75只。对照组饲喂基础日粮,试验组饲喂在基础日粮上添加3 g/kg浓度的中草药日粮。试验结果表明:在22～28 d,肉鸡增重效果最佳,试验组平均日增重比对照组提高了28.5%,差异极显著(p 0.01)。在1～42 d试验组与对照组相比体重提高了10.40%,差异极显著(p 0.01);平均日增重升高10.96%,差异不显著(p0.05);平均日耗料量显著降低9.42%,差异显著(p 0.05),料重比降低13.86%,成活率升高0.34%,差异不显著(p0.05)。经济效益试验组比对照组平均每只鸡增收1.248元/只。     

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