日粮硫、镁水平对肉鸡血液酸碱平衡和胫骨软骨发育不良的影响

在玉米 豆粕日粮中,添加３ 个水平的Ｍｇ０ 和（ＮＨ４）２ＳＯ４ ,使日粮中的硫、镁水平分别达到０ ．４０ ％ 、０ ．６５ ％ 、０ ．９０ ％ 和０ ．１７ ％ 、０ ．３７ ％ 、０ ．５７ ％ ,组成９ 个处理日粮,饲喂４０５ 只艾维茵肉用公雏,研究日粮电解质平衡对２１ 日龄肉鸡生长性能、胫骨软骨发育不良（ＴＤ） 发生、血液酸碱平衡的影响。在一定范围内日粮高硫具有诱食作用。日粮高镁同时降低了采食量、日增重和饲料效率（Ｐ＜ ０ ．０５） 。日粮高硫明显降低了ＴＤ 发生率和生长板厚度（Ｐ＜ ０ ．０５） ,高镁则起到相反的作用。日粮电解质平衡与肉鸡ＴＤ 发生率呈线性负相关（Ｒ＝ － ０ ．８２５） 。虽然日粮镁、硫水平对血液ｐＨ 影响不显著,但日粮高硫降低了碱超和碱贮（Ｐ＜ ０ ．０５） ,酸化了血液;日粮高镁则增加了碱超（Ｐ＜ ０ ．０５） ,起到了碱化作用。试验结果表明,由日粮硫、镁水平调节的电解质平衡可能通过改变血液酸碱平衡,成为影响肉鸡胫骨软骨发育的重要因素。     

日粮中氯、镁、非植酸磷水平和豆饼对肉仔鸡胫骨软骨症的影响

本试验为2~4因子试验,研究日粮中氯、镁、非植酸磷水平和不同豆饼对肉用仔公鸡生长性能、胫骨和血清中钙、磷、镁、钠、钾和血清氯离于含量以及胫骨软骨症的影响。结果表明,高氯和/或高磷的摄取导致仔鸡胫骨软骨症的高发病率,而这种高氯和/或高磷日粮诱发胫骨软骨症的作用可通过提高日粮中的镁水平来缓解,但伴随着仔鸡生长速度的降低。胫骨软骨症的高发病率与仔鸡胫骨钠,血清氯(Cl~-)含量成显著正相关(r=0.77,p<0.01;r=0.51,P<0.05)与仔鸡血清钾(K~+)含量成显著负相关(r=-0.50,P<0.05)。日粮中不同豆饼对仔鸡胫骨和血清中矿物元素含量的影响依赖于日粮中氯、镁、非植酸磷的水平,而豆饼本身对胫骨软骨症的发病率没有显著影响(P>0.05)。     

有机稀土饲料添加剂饲喂生长肉猪试验

研究稀土饲料添加剂对高寒地区生长肉猪的效果，选用４０～５０日龄苏×本杂二代仔猪４０头，按照对等相似原则划分为４组，每组１０头，试验Ｉ组，２组和３组日粮中分别添加０．０１％，０．０１５％，０．０２％稀土饲料添加剂ＲＣＴ－３，对照组不添加剂稀土。经过１８０天饲料试验结果，试验１组，２组和３组的平均日增重分别比对照缚提高１３．２５％（Ｐ〈０．０１），１０．２％（Ｐ〈）．０５）和３．０４％（Ｐ〉０．０５）     

园叶决明饲养石岐杂鸡

试验选用３００只石岐杂鸡分成３组，试验Ⅰ，Ⅱ组，对照组，２个试验加入不同比例的园叶决明草粉代替日粮中部分稻谷饲养肉鸡。试验结果表明：在肉鸡日粮加中入园叶决明草粉的数量为，小鸡阶段２％～４％，中鸡阶段５％～７％，其增重速度，饲料报酬，肉料比，两个试验组与对照组差异均不显著，而饲料成本，每增重１ｋｇ试验Ⅰ，Ⅱ组分别比对照组降低０．０３元和０．２０元，而且饲养一只肉鸡开支节省稻谷０．２３～０．３３ｋｇ。     

石岐黄肉鸡前期日粮适宜的能量和蛋白质水平的研究

本试验旨在研究优质石岐黄肉鸡前期日粮适宜的能量（ＭＥ）和蛋白质（ＣＰ）水平。试验共设４（ＭＥ）×５（ＣＰ）共２０个处理,各５个重复,每重复１６只母雏。ＭＥ（ＭＪ／ｋｇ）水平分别为１１．３,１１．９,１２．６,１３．２,ＣＰ（％）分别为１６．０,１７．５,１９．０,２０．５,２２．０。结果表明,以增重为衡量指标,石岐黄肉鸡生长前期日粮适宜的ＭＥ和ＣＰ水平分别为１２．６ＭＪ／ｋｇ和１９．０％;以能量存留率、氮存留率和饲料转化率为衡量指标,则适宜水平分别为１３．２ＭＪ／ｋｇ和２０．５％。     

蛋鸡开产前后适宜钙水平的研究

选育发育正常的１３ 周龄罗曼商品蛋鸡６００ 只， 随机分为３ 组， 每组２００ 只， 每组４ 个重复。７ 天预试期，其间调整各组鸡使组间体重差异不显著；正式期９８ 天。３ 组鸡日粮组成及营养水平和饲养条件相同，干粉料每天饲喂两次，自由采食及饮水。各组日粮钙水平随产蛋率的增加而增加。试Ⅰ组１４ ～１８ 周龄为２ ．０ ％ ，１８ 周龄～５ ％ 产蛋率为２ ．０ ％ ，５ ％ ～５０ ％ 产蛋率为３ ．４ ％ ，＞ ５０ ％ 产蛋率为３ ．４ ％ ； 试Ⅱ组四个阶段日粮钙水平分别为：０ ．９ ％ 、２ ．０ ％ 、３ ．４ ％ 及３ ．４ ％ ；对照组分别为０ ．９ ％ 、２ ．０ ％ 、２ ．０ ％ 及３ ．４ ％ 。试验期间每日观察鸡的精神状态、采食及粪便情况；每日按组别测定采食量、产蛋率等；每７ 天测一次蛋壳厚度及蛋重。结果表明：①试验期间两试验组鸡健康状况良好，对照组有２ 只鸡瘫痪。②产蛋率达５ ％ 的日龄三组间接近； 达５０ ％ 产蛋率的日龄对照组稍迟于两试验组； 达９０ ％ 产蛋率的日龄试Ⅰ组早于试Ⅱ组２ 天，早于对照组４ 天。③试验期间三组平均产蛋率分别为： ５２ ．４ ％ 、５６ ．３ ％ 及５４ ．７ ％ 、试Ⅰ组与试Ⅱ组差异显著，与对照组差异极显著，试Ⅱ组与对照组差异显著     

双乙酸钠饲喂AA肉仔鸡的效果

用双乙酸钠添加在日粮中饲喂ＡＡ肉仔鸡，结果表明，前期添加量０．１％，后期添加量０．２％～０．３％，肉仔鸡出栏体重比对照组提高７％左右，料重比降低０．４，相近出笼体重由５６天减少为４９天，并有效地防治大杆菌和病原微生物所致的疾患，试期内每只试鸡比对照组增收２．４０元。     

饮水高氯诱发肉鸡胫骨软骨发育不良的试验研究

２４０羽健康ＡＡ肉鸡随机均分为对照组，试验１组，试验２组。从８日龄志分别饮用含Ｃｌ０．０％、０．０９％、０．１８％的饮水以观察肉鸡胫骨软骨发育情况，同时对其进行了Ｘ射线、骨密度、血清学和形态学的研究。结果表明：（１）饮水高氯可增加胫骨软骨发育不良的发病率。（２）３周后病鸡胫骨近端的Ｘ射线可透区与软骨增生区的形态一致，其承重侧的骨皮质增厚。（３）试验组鸡的胫骨骨密度较对照组稍高，但差异不显著。骨密度     

不同锰、锌源对肉仔鸡生产性能的影响

选用ＡＡ商品代肉用雏鸡３６０羽，随机分为三组，即Ⅰ、Ⅱ、Ⅲ组，每组１２０羽，各组均以玉米－豆粕为基础日粮并在预混料中外加不同锰、锌源（氨基酸螯合物和硫酸盐形式），并且各处理氨基酸水平相同，Ⅰ组的日粮预混料中外加０．３％的氨基酸螯合锰、锌；Ⅱ组外加氨基酸螯合锰、锌０．１５％和锰８０ｍｇ（ＭｎＳＯ＿４·Ｈ＿２Ｏ）、锌４０ｍｇ（ＺｎＳＯ＿４·７Ｈ＿２Ｏ）；Ⅲ组外加锰１６０ｍｇ（ＭｎＳＯ＿４·Ｈ＿２Ｏ）、锌８０ｍｇ（ＺｎＳＯ＿４·７Ｈ＿２Ｏ）。试验期４９天，全期分０～３周龄、４～６周龄、７周龄三阶段。结果表明，用氨基酸螯合锰、锌替代预混料中的无机硫酸盐形式，可使饲料成本降低，日增重提高６．６％．饲料消耗降低５．７％，肉仔鸡腿病发生率降低。     

饲粮中添加棉油和赖氨酸对断奶仔猪生长性能影响的探讨

在ＣＰ１８％水平下，在不添加油脂和添加３％棉油的日粮中各自分别添加０．１５％和０．５％赖ＡＡ，形式４种日粮，进行饲养试验，探讨对断奶仔猪生长性能的影响，３０ｄ饲养试验表明，不添加棉油日粮日增重明显高于棉油日粮，组间差异极显著；添加０．１５％和０．３０％赖ＡＡ日粮，组内差异不显著。试验期间各组腹泻次数不多，说明此阶段ＣＰ１８％水平下，以不添加加棉油且赖ＡＡ为１．１５％更适宜     

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.     

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.     

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.     

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