宁夏滩羊公羊育成期能量需要量和代谢规律的研究

利用"中型开放回流式呼吸测热装置",采用梯度饲养、消化代谢试验,结合生长代谢呼吸测热和绝食代谢呼吸测热试验,对育成期宁夏滩羊公羊的能量需要量和代谢规律进行了系统的研究.结果表明:①在(20±1)℃下滩羊公羊育成期绝食产热为203.49 kJ/(W0.75·d);同样温度环境条件下生长代谢畜体产热为369.53 kJ/(W0.75·d);能量平衡的结果表明,滩羊公羊在育成前期沉积蛋白质的能力高于后期,沉积体脂肪的能力后期高于前期.②通过绝食产热测得滩羊公羊育成期维持净能244.29 kJ/(W0.75·d),维持代谢能305.3 kJ/(W0.75·d),km=0.8.③热增耗HI=125.27 kJ/(W0.75·d).④滩羊公羊育成前期代谢能需要量MER=305.33 kJ/(W0.75·d)·d+618.4×△W0.136(△W,kg).     

饲喂水平对杂交肉羊(公)营养物质代谢及能量需要量的影响

本试验旨在利用开放式呼吸测热装置研究肉羊(公)营养物质代谢及能量需要参数。采用完全随机试验设计,将15只出生日期相近、体况良好、体重相近的杜泊×小尾寒羊F1代公羔随机分成3组(每组5只羊),分别按自由采食(AL)、限饲70%(IR70)和限饲40%(IR40)3个饲喂水平投喂饲粮。分别在体重达到22和35 kg时进行试验,每期试验包括消化代谢试验(预试期3 d,正试期5 d)和呼吸代谢试验(适应呼吸代谢室24 h,连续测定5 d)。结果表明:1)随饲喂水平降低,肉羊的平均日增重极显著降低(P0.01),IR40组末重极显著低于AL组(P0.01)。2)随饲喂水平降低,肉羊干物质和氮采食量极显著降低(P0.01),但是这2者的表观消化率没有显著变化(P0.05)。3)随饲喂水平降低,肉羊甲烷产生量、甲烷能及产热量均降低,IR40组均极显著低于AL组(P0.01)。4)肉羊绝食60 h,呼吸熵为0.71,第1期和第2期甲烷产生量分别为0.86和1.18 L/d,绝食产热量分别为0.211和0.260 MJ/kg W0.75,维持净能分别为0.252和0.312 MJ/kg W0.75。综合得出,随饲喂水平降低,肉羊的生产性能、营养物质采食量、平均日增重、甲烷产生量、甲烷能及产热量均降低,但营养物质表观消化率没有显著变化。绝食状态下,甲烷产生量为0.86~1.18 L/d,绝食产热量为0.211~0.260 MJ/kg W0.75,维持净能为0.252~0.312 MJ/kg W0.75。     

肉羊维持净能需要量的不同测定方法研究

研究旨在通过回归法和绝食法测定小尾寒羊×杜泊羊杂交肉用羊(杜×寒肉羊)在生长期(20 kg)和育肥期(40 kg)时的维持净能需要量,比较测定方法间的异同。第1阶段选取24只体重(20±3)kg的杜×寒肉羊,第2阶段选取24只体重(40±5)kg杜×寒肉羊,公母各半,2个阶段分别分为4组,每组6个重复。前3组为回归法测定维持能量需要量,分别按照自由采食量的100%、80%、60%进行限饲,第4组为维持需要组。试验羊限饲7 d后各组随机选取2只羊,称重后转入特制代谢笼中适应1 d后进行4 d消化代谢试验后转入呼吸代谢舱进行4 d的呼吸测热试验,每次试验期为16 d,每阶段重复3次试验。结果表明:生长期杜×寒羔羊维持净能需要量为224.08 kJ/kg BW^0.75(回归法)、232.84 kJ/kg BW^0.75(绝食法);育肥期杜×寒肉羊维持净能需要量为271.33 kJ/kg BW^0.75(回归法)、279.20 kJ/kg BW^0.75(绝食法)。绝食法测定维持净能需要量略高于回归法,2种方法无...     

24月龄生长母水牛绝食代谢的研究

用传统开路式牛用呼吸面具对24月龄母水牛绝食产热(Fasting heat production,FHP)进行研究。结果表明:①24月龄母水牛FHP为306.013kJ/kgW0.75·d;每天排出内源尿氮(EUN)为39.66g;单位代谢体重每天排出EUN为0.48g;蛋白分解产热占总产热量为17.13%;EUN与FHP比值为1.60mg/kJ。②24月龄母水牛维持净能需要:NEm=397.817kJ/W0.75·d。     

12月龄生长母水牛绝食代谢的研究

用传统开路式牛用呼吸面具对12月龄母水牛绝食产热(FHP)进行研究。结果表明:①12月龄母水牛FHP为334.03KJ/KgW0.75·d;每天排出内源尿氮(EUN)为31.06g;代谢体重每天排出EUN为0.53g;蛋白分解产热占总产热量为17.99%;EUN与FHP比值为1.60mg/KJ。②12月龄母水牛维持净能需要:NEm=400.84KJ/W0.75d。     

贵州香猪内源氮与内源氨基酸代谢规律研究

选择3.5～4.0月龄、遗传来源相似、体重(12±2) kg的贵州从江香猪、剑白香猪去势公猪各6头,采用无氮饲粮(NFD)法和NFD+5%酶解酪蛋白(EHC)法进行代谢试验,测定贵州香猪内源氮与内源氨基酸的代谢规律,探索贵州香猪的维持蛋白质和氨基酸需要量.研究显示,贵州香猪内源氮排泄量为0.212 g/d W0.75,内源氨基酸排泄量为1.463 g/d W0.75.结果表明,贵州香猪可消化粗蛋白质维持需要量(DCPm)为1.91 g/d W0.75,可消化氨基酸维持需要量为2.10 g/d W0.75,以Lys为100建立贵州香猪维持需要可消化氨基酸模型为:Lys 100、Thr 54、Val 188、Met 40、Ile 79、Leu 126、Phe 101、His 25、Arg 58、Trp 17.     

14～15月龄母水牛能量需要量初探

选用12头体况良好、14～15月龄、体重(262±3.5)kg的健康母水牛,按随机区组的试验设计分为3组进行饲养试验、消化代谢试验和气体代谢试验,以获得14～15月龄母水牛能量需要量。3组试验日粮均由精料和粗料(象草和发酵菠萝皮)组成。3组日粮粗蛋白水平一致(11.10%),能量水平不同,产奶净能分别为6.28(第1组),6.14(第2组)和6.00 MJ/kg(第3组)。饲养试验包括15 d的预试期和30 d的正试期,在正试期的第24和28天分别进行为期7 d的消化代谢试验和3 d的气体代谢试验,饲养试验结束后,试牛断料不断水,从绝食的第4天起进行为期2 d的绝食代谢试验。结果表明:14～15月龄母水牛正常采食状态下水牛畜体产热(HP)为0.638 MJ/(W0.75.d),绝食状态下水牛畜体产热(FHP)为0.321 MJ/(W0.75.d),热增耗(HI)为0.317 MJ/(W0.75.d),能量消化率为66.49%,能量代谢率为54.23/%。14～15月龄母水牛用于维持的净能需要量为0.401 MJ/(W0.75.d),每增重1 kg所需要的净能为12.22 MJ。14～15月龄母水牛总净能需要量可以按以下公式计算:NE(MJ/d)=(0.401+0.184△W)W0.75;NE(MJ/d)=0.401 W0.75+12.22△W,式中△W为日增重(kg/d)。     

乳肉兼用水牛不同生长阶段绝食代谢的研究

用传统开路式牛用呼吸面具对12,18和24月龄乳肉兼用水牛绝食产热(FHP)进行研究。结果表明:12,18和24月龄乳肉兼用水牛FHP分别为334.03,328.55和306.01KJ/(kgW0.75·d);每天每头排出内源尿氮(EUN)分别为31.06,35.62和39.66g;单位代谢体重每天排出EUN分别为0.53,0.50和0.48g;蛋白分解产热占总产热量分别为17.99%,17.35%和17.98%;EUN与FHP比值分别为1.60,1.54和1.60mg/KJ。乳肉兼用生长水牛维持净能需要量:NEm=402.152KJ/(kgW0.75·d)。绝食代谢与体重指数关系为:FHP[KJ/(kgW0.75·d)]=877.864W0.57,(n=15,r=0.7075)。乳肉兼用生长水牛代谢体重为W0.57kg。     

环境温度对哈白生长猪代谢产热量的影响

本试验利用开放式呼吸测热装置在2个环境温度(13℃、23℃)及定量采食(2×35 g/kg0.75*d)条件下对哈白猪(21±1 kg)的代谢产热量进行测定.试验结果表明环境温度对产热量有显著影响,13℃、23℃的产热量分别为35.7 kJ/kg0.75*h和26.3 kJ/kg0.75*h.     

杜湖杂交F1代母羊妊娠期能量和蛋白质维持需要量

本研究旨在确定杜泊羊×湖羊(杜湖)杂交F1代母羊妊娠期能量和蛋白质维持需要量,为该杂交组合肉羊饲粮配制提供较为合理的能量和蛋白质需要标准。分为饲养试验、消化代谢试验和呼吸测热试验。选取15只月龄(9月龄)、体重[(43.34±1.37)kg]相近的母羊,经同期发情、自由交配后随机分为自由采食组、70%自由采食量、50%自由采食量组,每组5只母羊。在妊娠期40、100、130 d分别采用全收粪法收集粪尿,同时进行呼吸测热试验,计算得到母羊在不同妊娠时期氮、能量的表观代谢参数,依据消化代谢试验和呼吸测热试验结果分别利用沉积氮和食入氮、产热量的对数和代谢能采食量建立异速回归方程,最终得到该杂交组合在妊娠期40、100、130 d时维持净氮、维持净能、维持代谢能需要量。结果表明:1)氮表观消化率在妊娠40、100、130 d时分别为56.16%~62.24%、60.43%~65.47%、58.79%~62.01%。2)总能表观消化率在妊娠40、100、130 d时分别为51.18%~64.25%、60.86%~66.17%、63.20%~67.36%。3)在母羊妊娠40、100、130 d时维持净氮分别为287.9、301.3、430.7 mg/(kg W0.75·d);维持净能分别为194.01、244.59、256.08 k J/(kg W0.75·d);维持代谢能分别为283.18、412.26、468.56 k J/(kg W0.75·d)。本研究最终得到了杜湖杂交F1代母羊妊娠期能量、蛋白质需要量指标,包括维持净能、维持代谢能、维持净氮。     

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