维生素C对应激蛋鸡血液生化指标的影响

研究热应激和免疫接种应激下,添加不同剂量维生素C（VC）对蛋鸡肌酸磷酸激酶和血糖的影响。日粮中VC添加浓度为0、200、400和1200mg／kg,环境温度为32℃,接种疫苗为新城疫疫苗（NDV）或水（NNDV）,试验期28d。试验结果表明,添加VC可降低热应激和免疫应激蛋鸡的肌酸磷酸激酶活性和血糖浓度。VC抗应激效果与其添加量密切相关,400mg／kgVC抗应激效果最好。建议在应激蛋鸡日粮中添加适量VC。     

日粮添加苜蓿皂苷对蛋鸡生产性能、鸡蛋胆固醇及常规蛋品质的影响

选用288只400日龄海兰褐商品蛋鸡,随机分为4组,每组72只鸡,各组设4个重复,每个重复18只鸡,采用单因素方差研究苜蓿皂苷对蛋鸡生产性能及鸡蛋胆固醇及常规蛋品质的影响.在玉米-豆粕型日粮基础上添加0、30、60、90mg/kg的苜蓿皂苷来饲喂蛋鸡,试验期60d.结果表明:日粮中添加苜蓿皂苷,时产蛋率、平均蛋重、耗料量和料蛋比没有显著影响(P＞0.05).综合试验30d和60d结果,日粮中添加苜蓿皂苷60mg/kg,降低蛋黄胆固醇浓度及全蛋胆固醇含量效果最好(P＜0.01);日粮中添加苜蓿皂苷60mg/kg、90mg/kg,提高蛋壳厚度效果最好(P＜0.05);哈氏单位以60 mg/kg组最高(P＜0.05).综合分析得出,日粮中添加60mg/kg的苜蓿皂苷效果最佳.     

热应激环境下磷脂VC对蛋鸡生产性能的影响

选37周龄罗曼蛋鸡288只,在热应激(平均舍温29.5℃,最高舍温35.2℃)环境下,研究了日粮中添加不同剂量磷脂VC对蛋鸡生产性能的影响。结果表明,与对照组相比,添加300mg/kg的磷脂VC组的采食量提高了6%(P<0.01)@产蛋数和产蛋率分别提高3.6%和3.2%(P<0.05),破蛋率、死亡率和失重率降低。100mg/kg的磷脂VC组可改善蛋鸡生产性能的各项指标但效果不显著。表明日粮中添加300mg/kg磷脂VC能明显提高热应激蛋鸡的采食量和产蛋率,改善蛋鸡的生产性能。     

日粮中不同锌添加水平对蛋鸡生产性能及蛋中锌含量的影响

为探讨不同锌添加水平的日粮对蛋鸡生产性能及蛋锌含量的影响,将氧化锌分别以1200mg/kg、1400mg/kg、1600mg/kg、1800mg/kg、2000mg/kg五种锌含量水平添加到蛋鸡基础日粮中,饲喂166日龄的海兰灰产蛋鸡28d,观察蛋鸡生产性能及第18天和第28天蛋锌含量的变化。结果表明:随日粮中锌添加水平的增加,采食量随着日粮锌添加水平的升高表现越明显;产蛋率随着日粮中锌添加水平的增高显著下降(P0.05);饲喂锌含量水平添加为2000mg/kg的鸡蛋锌含量显著高于其他处理组(P0.05),其余处理组鸡蛋锌含量差异不显著(P0.05)。     

枯草芽孢杆菌对产蛋后期蛋鸡生产性能和蛋壳品质的影响

本试验旨在研究饲粮中添加枯草芽孢杆菌对产蛋后期蛋鸡生产性能和蛋壳品质的影响。选取420只产蛋率和体重相近的健康52周龄海兰褐蛋鸡,随机分为4个组,每组7个重复,每个重复15只鸡。对照组饲喂玉米-豆粕型基础饲粮,试验组分别在基础饲粮中添加200、400和800 mg/kg枯草芽孢杆菌。预试期1周,正试期12周。结果表明,与对照组相比:1)饲粮中添加200、400和800 mg/kg枯草芽孢杆菌对产蛋率和平均蛋重无显著影响(P0.05),但显著降低了平均日采食量(P0.05);饲粮中添加400和800 mg/kg枯草芽孢杆菌显著降低了料蛋比(P0.05)。2)饲粮中添加200、400和800 mg/kg枯草芽孢杆菌显著增加了蛋壳厚度(P0.05),显著降低了破软蛋率(P0.05);饲粮中添加800 mg/kg枯草芽孢杆菌显著提高了蛋壳强度和壳重比例(P0.05)。3)饲粮中添加800 mg/kg枯草芽孢杆菌改善了蛋壳的超微结构,显著增加了蛋壳中钙含量(P0.05)。由此可见,饲粮中添加枯草芽孢杆菌可以改善产蛋后期蛋鸡生产性能,提高蛋壳品质,降低破软蛋率。本试验条件下,饲粮中添加800 mg/kg枯草芽孢杆菌为宜。     

抗菌肽粗提物对蛋鸡产蛋性能、蛋品质、血清生化指标和肠道菌群的影响

本试验旨在研究日粮不同水平抗菌肽粗提物对蛋鸡产蛋性能、蛋品质、血清生化指标和肠道菌群的影响。将480只210日龄海赛克斯褐壳蛋鸡,随机分成4组,每组4个重复,对照组饲喂基础日粮,试验组分别饲喂在基础日粮中添加200、400、600 mg/kg抗菌肽粗提物的试验日粮。结果表明:与对照组相比,日粮添加200 mg/kg抗菌肽粗提物能显著提高蛋鸡的蛋黄相对重(P<0.05),对回肠内大肠杆菌有显著抑制作用(P<0.05),而对其他指标并无显著性影响(P>0.05);日粮添加400 mg/kg抗菌肽粗提物能显著提高蛋鸡的产蛋率和蛋黄相对重(P<0.05),降低白蛋白和血糖含量(P<0.05),显著降低回肠大肠杆菌的数量(P<0.05);日粮添加600 mg/kg抗菌肽粗提物能够显著提高血清SOD活性(P<0.05),而对其他指标无显著性影响(P>0.05)。综上所述,蛋鸡日粮中添加400 mg/kg抗菌肽粗提物效果最佳。     

添加V_C对热应激蛋鸡免疫性能的影响

将96羽蛋鸡随即分为8组,每组4个重复,全部饲养于控温室中(温度为32℃),研究热应激下日粮中VC不同添加浓度对新城疫接种蛋鸡抗体滴度(HT)和T淋巴细胞ANAE阳性率等免疫性能的影响。试验采用2×4析因试验设计,其中VC的添加浓度为0、200、400、1 200 mg/kg 4个水平,免疫接种分为接种新城疫疫苗与不接种2个处理。试验持续35 d。结果:对于接种新城疫疫苗蛋鸡,400 mg/kg VC组HT与T淋巴细胞ANAE阳性率极显著高于其他组(P<0.01),其他3组间HT、T淋巴细胞ANAE阳性率无显著差异;对于未接种蛋鸡,400 mg/kg VC组HT与T淋巴细胞ANAE阳性率显著高于不添加VC组(P<0.05),与200 mg/kg VC组、1 200 mg/kg VC组间差异不显著。热应激下,添加VC可提高蛋鸡的免疫性能。     

日粮中不同碘添加水平对蛋鸡生产性能及蛋碘含量的影响

为探讨不同碘添加水平的日粮对蛋鸡生产性能及蛋碘含量的影响,将碘酸钙分别以0.35mg/kg、10mg/kg,20mg/kg、30mg/kg、40mg/kg和50mg/kg六种碘含量水平添加到蛋鸡基础日粮中,饲喂166日龄的海兰灰产蛋鸡4周,观察蛋鸡生产性能及第18d和第28d蛋碘含量的变化。结果表明:随日粮中碘添加水平的增加蛋鸡采食量呈现下降趋势,但产蛋率、鸡蛋重、鸡体重无显著影响(p0.05)。在试验的第18d和第28d,随着日粮中碘添加量的增加碘在鸡蛋中的沉积显著增加(p0.05),同一试验日内呈现幂指数关系。     

饲粮中添加甜菜碱对热应激蛋鸡生产性能、蛋品质及血清生化指标的影响

本试验旨在研究饲粮中添加甜菜碱对热应激蛋鸡生产性能、蛋品质及血清生化指标的影响。选用健康的22周龄商品代罗曼褐蛋鸡600只,随机分成5组,每组8个重复,每个重复15只鸡。Ⅰ组为正对照组,饲喂基础饲粮,正常温热环境,温湿指数(THI)介于64.9~68.9;Ⅱ组为负对照组,饲喂基础饲粮,热应激环境,THI72;Ⅲ~Ⅴ组分别在基础饲粮中添加200、400和600 mg/kg甜菜碱,均为热应激环境,THI72。试验期为14周。结果表明,各组间平均日采食量、料蛋比和破蛋率差异不显著(P0.05)。与Ⅰ组相比,Ⅱ组显著降低了入舍母鸡产蛋率、入舍母鸡产蛋重及血清总蛋白(TP)含量、碱性磷酸酶(AKP)活性(P0.05),显著提高了血清中谷草转氨酶(GOT)、肌酸激酶(CK)和谷丙转氨酶(GPT)活性(P0.05)。与Ⅱ组相比,Ⅳ组入舍母鸡产蛋率、入舍母鸡产蛋量和血清TP含量均显著提高(P0.05),Ⅴ组入舍母鸡产蛋量及血清TP、白蛋白(ALB)含量也显著提高(P0.05),而Ⅳ组和Ⅴ组的血清CK、GPT活性却显著降低(P0.05),且Ⅴ组的血清甘油三酯(TG)含量也显著降低(P0.05)。综上所述,热应激可使产蛋鸡的新陈代谢和生理机能发生变化,导致生产性能下降,而饲粮中添加甜菜碱可以提高入舍母鸡产蛋率和入舍母鸡产蛋重,并改善热应激对蛋鸡的损伤,饲粮中甜菜碱的适宜添加量为400 mg/kg。     

黄芪多糖对蛋鸡生产性能、蛋品质及经济效益的影响

为了研究添加不同水平的黄芪多糖(100 mg/kg、200 mg/kg、300 mg/kg)对蛋鸡生产性能和蛋品质的影响，选200羽海兰褐壳蛋鸡，随机分为4组，分别饲喂基础日粮和添加不同水平的黄芪多糖的日粮，并进行生长性能指标和蛋品质性能指标的测定。结果显示，黄芪多糖的三种添加水平对蛋鸡日产蛋量有明显提高，添加量越多，蛋壳厚度越厚以及蛋黄色泽越深，鸡蛋品质提升越多，从而经济效益越高。因此日常蛋鸡饲养中建议日粮中添加300mg/kg黄芪多糖，以获得理想经济效益。     

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