光照在肉鸭生产中的应用研究

用1日龄樱桃谷肉鸭900只，要用二因素三水平的完全随机设计研究光照制度对肉鸭生产性能和脂肪沉积的影响。结果表明，光照制度和公母的分群方式分别对肉鸭的日增重有显著影响（P＜0．05）和极显著影响（P＜0．01）；对肉鸭的死亡率和饲料转化率均无显著影响（P＞0．05）；对肉鸭的腹脂率和脂率均有极显著的影响（P＜0．01）。以间隙光照制制和公母分群饲养的效果最好。     

光照在肉鸭生产中的应用研究

试验选用 1日龄樱桃谷肉鸭 90 0只 ,随机分 9个组 ,每组 2个重复 ,每个重复 5 0只肉仔鸭。试验组采用二因素、每个因素三个水平的完全随机设计 ,以研究光照制度对肉鸭生产性能和脂肪沉积的影响。结果表明 :光照制度和公母的分群方式分别对肉鸭的日增重有显著影响 (P <0 .0 5 )和极显著影响 (P <0 .0 1) ;对肉鸭的死亡率和饲料转化率均无显著影响 (P >0 .0 5 ) ;对肉鸭的腹脂率和皮脂率均有极显著的影响 (P <0 .0 1)。以间歇光照制和公母分群饲养的效果最好     

光照制度对肉鸭生产性能和脂肪沉积的影响

本试验选用１日龄樱桃谷肉鸭９００只，随机人灵９个组，每组２个重复，每个重复５０只肉仔鸭。试验组采用二因素、每个因素三个水平的完全随机设计，以研究光照制度对肉鸭生产性能和脂肪沉积的影响。结果表明：（１）日增重：光照制度和公母的分解方式对日增重分别有显著影响（Ｐ〈０．０５）和极显著影响（Ｐ〈０．０１），间歇光照组显著优于渐增光照组（Ｐ〈０．０５），连续光照组与间歇光照组，渐增光照组差异不显著（Ｐ〉０．０５），连续光照组与歇光照组、渐增光照组差异不显著（Ｐ〉０．０５）；公鸭组的日增重极显著高于母鸭组和公母混群组（Ｐ〈０．０１），母鸭组与公母混群组差异显著（Ｐ〈０．０５）。（２）死亡率，光照制度及公母的分群方式对肉鸭的死亡率均无显著影响（Ｐ〉０．０５）。（３）饲料转化率；光照制度及公母的分群方式对肉鸭的饲料转化率均无显     

光照制度和性别方式对肉鸭性能的影响

试验选用 1日龄樱桃谷肉鸭 90 0只 ,随机分为 9个组 ,每组 2个重复 ,每个重复 5 0只肉仔鸭。试验组采用二因素、每个因素三个水平的完全随机设计 ,以研究光照制度和性别方式对肉鸭生产性能和脂肪沉积的影响。结果表明 ,光照制度和性别方式分别对肉鸭的日增重有显著影响 (P <0 0 5 )和极显著影响 (P <0 0 1) ;对肉鸭的死亡率和饲料转化率均无显著影响 (P >0 0 5 ) ;对肉鸭的腹脂率分别有极显著影响 (P <0 0 1)和有显著影响 (P <0 0 5 ) ;对肉鸭的皮脂率均有极显著的影响 (P <0 0 1)。以间隙光照制度和公母分群饲养的效果最好。     

光照在肉鸭生产中的应用研究

用1日龄樱桃谷肉鸭900只,采用二因素三水平的完全随机设计研究光照制度对肉鸭生产性能和脂肪沉积的影响.结果表明,光照制度和公母的分群方式分别对肉鸭的日增重有显著影响(P＜0.05)和极显著影响(P＜0.01);对肉鸭的死亡率和饲料转化率均无显著影响(P＞0.05);对肉鸭的腹脂率和皮脂率均有极显著的影响(P＜0.01).以间隙光照制和公母分群饲养的效果最好.     

间歇光照对肉鸭生产性能和经济效益的影响

本试验选用1日龄樱桃谷肉鸭20只，随机分为2个组，每组2个重复，每个重复50只肉仔鸭，试验采用单因素试验设计，以探讨间歇光照制度对肉鸭生产性能和经济效益的影响。结果表明：间歇光照制度对肉鸭的增重，死亡率和饲料转化率均无显影响（P＞0．05）。对采食量有显影响（P＜0．05）；对经济效益有显影响（P＜0．05）。     

间歇光照对肉仔鸡生产性能和氮存留的影响

选用４００只７日龄艾维茵雏鸡（公母各半），随机分为２组（公母分饲，垫料平养），按２～４周龄，５～６周龄，７周龄３个生长阶段，分别比较间歇光照制度和连续光照制度对肉仔鸡生产性能、腹脂和先利用效率的影响。试验重复一次，结果表明，间歇光照（ＩＬ）能显著降低２８日龄前肉仔鸡体增重和来食量，但随后出现补偿生长，到４２日龄时，公鸡的生长速度能得到完全补偿，获得与连续光照（ＣＬ）相似的体重，而母鸡体重仍低于相应的ＣＬ组。母鸡受到的前期生长抑制要到４９日龄时才能得到完全补偿。ＩＬ虽然降低了全期采食量，但却改进了饲料报酬。ＩＬ极显著地降低了２８日龄腹胀率，显著降低了４２日龄和４９日龄腹胀率。氮平衡试验表明，ＩＬ可提高干物质消化率和氮利用效率。     

双乙酸钠对肉鸭生产性能的影响

选用一日龄健康樱桃谷肉鸭新生雏90只，随机分为3组，每组设3个重复，每个重复10只肉鸭，试验采用单因素完全随机试验设计。A组饲喂基础日粮，B、C组在基础日粮的基础上分别添加0．2％、0.4％的双乙酸钠。结果表明：日粮中添加双乙酸钠对提高肉鸭日增重、胸肌率、腿肌率有显著影响（P〈0．05）；对肉鸭的饲料转化率有极显著影响（P〈0．01）；对肉鸭的成活率、屠宰率和皮脂率无显著影响（P〉0．05）。B组日增重比A组提高了8．65％（P〈0．05），比C组提高了5_45％（P〉0．05）；B组料重比较A组降低了11．52％（P〈0．01），较C组降低了3．29％（P〉0．05）：B组的成活率与A组、C组间差异均不显著（P〉0．05）；B组每只肉鸭分别比A、C组多盈利1．04、1．06元。     

有机铬制剂对肉鸭生产性能和屠宰性能的影响

本试验选用1日龄樱桃谷肉鸭500只,随机分为5个组(4个试验组 1个对照组),每组4个重复,每个重复25只肉仔鸭。试验采用单因素完全随机设计。A组为对照组,喂以基础日粮;B组、C组、D组和E组为试验组,分别在基础日粮中添加0.1、0.2、0.3和0.4mg/kg吡啶羧酸铬(以铬计),试验期42天,以探讨日粮中添加有机铬对肉鸭生产性能和屠宰性能的影响。结果表明:试验组肉鸭的腹脂率和胸肌率极显著低于对照组(P<0.01),而生产性能和屠宰率与对照组之间差异不显著(P>0.05)。     

肉鸭日粮中补铬的效果研究

试验选用 1日龄樱桃谷肉鸭 500只,随机分为 5个组（ 4个试验组＋ 1个对照组）,每组 4个重复,每个重复 25只肉仔鸭。试验采用单因素完全随机设计。 A组为对照组,喂以基础日粮; B组、 C组、 D组和 E组为试验组,分别在基础日粮中添加 0.1mg/kg、 0.2mg/kg、 0.3mg/kg和 0.4mg/kg吡啶羧酸铬（以铬计）,试验期 42d,以探讨日粮中添加有机铬对肉鸭生产性能和屠宰指标的影响。结果表明：试验组肉鸭的腹脂率和胸肌率极显著低于对照组（ P0.05)。     

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.     

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.     

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     

Avian brood parasitism — a growing research area in behavioral ecology (part Ⅱ)

正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -