壳聚糖对黄羽肉鸡脂肪沉积的影响

选择健康49日龄黄羽肉用鸡（母）64只，随机分成4组。A为对照组饲喂基础日粮；B、C和D为试验组，分别在基础日粮中添加0．1％、0．3％和0．5％壳聚糖。饲养21d，研究日粮中添加壳聚糖对黄羽肉鸡脂肪沉积的影响。试验结果表明，在49日龄肉鸡日粮中添加0．1％、0．3％和0．5％壳聚糖能显著降低56、63和70日龄肉鸡的血清胆固醇（P〉0．05）和甘油三酯（P〉0．05）含量，降低70日龄肉鸡的腹脂率（P〉0．05），显著降低70日龄肉鸡的皮下脂肪，日粮中添加0．1％壳聚糖能达到较理想的降脂和降胆固醇的效果。     

降低蛋黄中胆固醇含量的研究

采用壳聚糖作载体，1，6-己撑二异氰酸酯作交联剂，通过共价键固载β-环糊精。在吸附时间为120min，蛋黄被稀释25倍时，蛋黄中胆固醇脱除达90．8％。β-环糊精／壳聚糖具有较好的重复使用性能，在重复使用5次后，胆固醇脱除率由90．8％下降至81．3％，仅降低了10．5％。测定结果表明，降低胆固醇含量后，鸡蛋的营养价值和性质没有发生明显的变化。     

生长猪血液生化指标与生产性能及肉质的关系

通过测定体重约50kg和90kg时雅南猪及其杂交后代长雅、约雅、汉雅、长杜雅（各20头）的血液生化指标，结果发现：随着年龄（体重）的增长，血清酶AKP和LDH活性变化较小（P＞0．05），血清总蛋白质和总胆固醇含量增加（P＜0．05），血液激素T3、T4含量降低（P＜0.01）。相关分析结果：90kg体重屠宰时AKP活性与日增重、饲料效率、瘦肉率和脂肪率的相关系数分另IJ为0．211、—0．286、0．231和—0．306（P＜0.01）；LDH活性与瘦肉率的相关系数为0．233（P＜005）；90kg作重时血清总胆固醇含量与瘦肉丰的相关和通径系数分别为—0．232和—0．131（P＜0．05）；90kg体重时血液生化性状与肉质性状间典型相关系数为0．536（P＜0．05），50kg体重血液生化性状与生产性能及肉质的相关相对较小。     

肉食动物肠道中芽孢杆菌的分离和降胆固醇能力的测定

为筛选、鉴定出降胆固醇芽孢杆菌,试验从健康狮、虎、狼等肉食动物粪便中分离得到3株菌,分别命名为L1、L2和L3。经形态学、染色特性和16S r DNA序列测定,鉴定出L1和L3为枯草芽孢杆菌,L2为蜡样芽胞杆菌。3株菌均具有良好的芽孢形成能力,芽孢形成率分别为82%、93%、91%。应用硫磷铁比色法对3株菌的体外降胆固醇能力进行测定,结果显示L1降胆固醇能力较弱,而L2、L3具有较强的胆固醇降解能力,其中L2在48 h内胆固醇降解率可达50%以上,这为相关降胆固醇药品和保健品的开发奠定了良好的基础。     

含莫纳可林K红曲降低鸡蛋胆固醇效果的研究

48只68周龄的海兰褐蛋鸡分成三组，按0.5％和10％比例分别添加含0．4％莫纳可林K红曲于各组日粮内，饲喂22d，观测其对鸡蛋胆固醇变化的影响。结果表明，投药后5—6d，10％添加组和5％添加组蛋黄胆固醇开始下降；15—22d的胆固醇含量与1～5d相比，10％添加组和5％添加组分别下降了9．02％和5．10％，而对照组升高了5．22％。     

β-葡聚糖对河蟹免疫功能的影响

用分别含0％(对照)、0．1％、0．5％、1％、2％β-葡聚糖的5种饲料饲养平均重量5．5 g左右的河蟹8周, 研究β-葡聚糖对河蟹的免疫功能的影响。每箱放养25只河蟹,每组3个重复。结果表明,试验各组河蟹的增重率、存活率差异均不显著。河蟹摄食试验饲料1周后,0．1％组和0．5％组的酚氧化酶(PO)活性显著升高(P<0．05),但β- 葡聚糖含量提高至1％以上时PO活性有下降的趋势;超氧化物歧化酶(SOD)活性表现为0．5％组显著高于其他各组(P<0．05),1％组较高但与对照组差异不显著;总抗氧化力(T-AOC)以1％和2％组显著高于其他各组。河蟹摄食试验饲料8周后,PO、SOD和T-AOC均表现为0．1％组最高,0．5％组其次,PO和SOD各组差异不显著,而T- AOC表现为0．1％组显著高于对照组(P<0．05)。     

甘氨酰谷氨酰胺对鸡生长、内源激素及相关基因表达的影响

9日龄优质粤黄鸡360只，随机分为4组，每组90只，通过饮水添加不同剂量的甘氨酰谷氨酰胺（Glycyl—Glu—tamine，Gly—Gln，剂量分别为0％、0．01％、0．05％和0．1％），观察Gly—Gln对粤黄鸡生长性能、内源激素和肝脏GHRmRNA、肌肉IGF—IR mRNA的影响。结果显示：一定剂量的Gly—Gln显著提高了试验组鸡的平均体重、胸肌率和腿肌率，显著降低了腹脂率；添加Gly—Gln的各试验组鸡血清中IGF-1、TSH、T3、T4水平均明显升高，而血清胰岛素水平降低；添加Gly—Gln的各试验组鸡肝脏GHRmRNA表达量略高于对照组，但差异不显著，而肌肉IGF—IRmRNA表达量低于对照组，其中0．01％和0．1％Gly—Gin组差异显著。以上结果提示，Gly—Gin可通过提高鸡血液IGF一1、TSH、T3、T4水平，降低血液胰岛素浓度而发挥其促生长和改善胴体品质的作用。     

肉食动物肠道中芽孢杆菌的分离和降胆固醇能力的测定

为筛选、鉴定出降胆固醇芽孢杆菌,试验从健康狮、虎、狼等肉食动物粪便中分离得到3株菌,分别命名为L1、L2和L3。经形态学、染色特性和16S r DNA序列测定,鉴定出L1和L3为枯草芽孢杆菌,L2为蜡样芽胞杆菌。3株菌均具有良好的芽孢形成能力,芽孢形成率分别为82%、93%、91%。应用硫磷铁比色法对3株菌的体外降胆固醇能力进行测定,结果显示L1降胆固醇能力较弱,而L2、L3具有较强的胆固醇降解能力,其中L2在48 h内胆固醇降解率可达50%以上,这为相关降胆固醇药品和保健品的开发奠定了良好的基础。     

苜蓿皂苷对山羊瘤胃体外培养液纤维降解酶活及纤维降解率的影响

本试验研究了不同水平的苜蓿皂苷对生长山羊瘤胃培养液中纤维降解酶活及纤维降解率的影响。在山羊瘤胃培养液中分别添加0％、1％、2％、3％的苜蓿皂苷，进行体外培养。结果表明：添加量为1％时未对纤维素酶和木聚糖酶活性造成不利影响．但超过1％时则降低其活性．添加苜蓿皂苷未对内切葡聚糖酶活性和纤维二糖苷酶活性产生影响。1％-3％的苜蓿皂苷极显著地提高DM降解率，分别增加了14．0％、28．2％和25．8％。说明添加苜蓿皂苷未对瘤胃降解纤维素及半纤维素的能力产生不利影响．     

动物脂脱除胆固醇及粉末化技术

该项目运用吸附法脱除动物脂肪(主要为猪脂)中的胆固醇,并运用乳化、包埋和喷雾干燥等技术将动物油脂制成便于运输、贮存、称量使用的粉末状油脂。另外,可根据不同需要,将粉末油脂含量提高到90％以上,以满足特殊行业的生产需要。其主要指标为:胆固醇脱除率>90,粉末油脂含油率>70％,水分含量<1％。     

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