新型塑料大棚规模化养猪舍环境状况的研究

对大棚舍、有窗舍和开放舍三种类型猪舍冬、夏季五项环境指标的测定与分析,研究新型塑料大棚规模化养猪舍环境状况与特点。结果表明,新型塑料大棚规模化养猪舍内冬季空气温度为11.3℃,相对湿度为72．3％,气流速度为0．19 m／s,二氧化碳浓度1000 ppm;夏季,空气温度26．5℃,相对湿度为80．2％,气流速度为0．72 m／s,二氧化碳浓度为640 ppm。大棚舍内环境冬、夏季均优于有窗舍,夏季与开放舍差异不明显。     

杭州规模化猪场两种通风模式下育肥舍内环境因子的比较分析

【目的】研究两种通风模式下杭州地区规模化猪场舍内环境参数及其分布规律,筛选出适合本地区推广的通风模式。【方法】选取杭州地区具有代表性的横向通风和纵向通风两种通风模式下育肥舍为研究对象,开展了早、中、晚3个不同时间点,进风口、舍中央和排风口3个不同位置的热环境参数、有害气体浓度的监测,持续监测1周。分析不同时间点和舍内不同位置对热环境参数(温度、相对湿度、风速)以及有害气体(氨气(NH₃)和硫化氢(H₂S))浓度的影响,并对两种模式下的热环境参数及有害气体浓度进行比较分析;采用空气沉淀法收集舍内环境中的细菌,并对细菌进行培养及统计分析,比较两种模式下育肥舍中细菌数量差异。【结果】两种通风模式下育肥舍相对湿度均低于国家标准,位置和各时间点对相对湿度影响不大,其中纵向通风舍内的相对湿度显著高于横向通风模式(P<0.05)。两种通风模式舍内平均温度没有显著性差异(P>0.05),舍内中午温度显著高于早、晚(P<0.05),位置对纵向通风舍内温度影响较大。纵向通风舍内平均风速为(1.09±0.42)m/s,符合国家标准且极显著高于横向...     

舍饲散栏卷帘奶牛舍温热环境年动态研究

为了研究舍饲散栏卷帘奶牛舍温热环境年动态变化,试验采用现场检测的方法,对奶牛舍连续12个月的气温、相对湿度和风速进行检测,分析各参数及其综合指数的年变化规律。结果表明:夏季(6—8月份)舍内气温最高,每天约有12 h气温高于25℃,温湿指数每天有8.5~15.5 h超过72,奶牛遭受轻度热应激;冬季(12—2月份)舍内气温最低,但相对湿度最高(可达64.5%~81.2%)。各季节舍内的平均气温分别为8.6~15.0℃(春季)、23.1~25.3℃(夏季)、6.9~16.5℃(秋季)和-2.9~0.6℃(冬季),春、夏、秋、冬季平均风速分别为0.10~0.13,0.46~0.80,0.05~0.14和0~0.01 m/s。说明卷帘奶牛舍夏季应加强防暑降温,冬季加强通风换气。     

有缓冲间湿帘-风机系统对兔舍环境调控效果研究

为实现一套系统满足全年环境调控需求,试验选取两栋安装有"有缓冲间湿帘-风机系统"的兔舍,冬季其中一栋舍一台风机安装变频器,另一栋舍全为定速风机。结果表明,冬季定速风机常速间歇通风的兔舍导向板进风口的风速为1.8 m/s,进入舍内风速降至0.1m/s,每日首次开启风机10 min CO_2浓度降低67.2%,间歇通风每次温度平均降低0.8℃;使用变频风机低速持续通风的兔舍,导向板进风口风速0.2m/s,进入舍内风速降到了0.05m/s,开启风机CO_2浓度降低59.5%,温度降低0.3℃;两舍缓冲间预热能够分别提升气流温度2℃、1.4℃。夏季在舍外温度32.4~38.2℃时,舍内温度能维持在26℃左右,温度降幅为9.0℃,舍内温湿指数(THI)为25.9;外墙湿帘的降温效率为87.2%,内墙湿帘的降温效率为0。夏季缓冲间和进风口气流导向能够显著降低入舍风速(外墙湿帘过帘风速0.8m/s,导向板进风口风速1.9m/s,进入舍内风速0.3m/s),且舍内气流分布均匀。综合环境指标说明,有缓冲间的湿帘-风机纵向通风系统克服了冬夏季进风端风速大、温度低的弊端,但舍内隔墙上的湿帘无降温潜力,建议去掉第一缓冲间及内墙湿帘。     

奶牛舍内外环境夏季气载微生物的检测

旨在比较夏季不同建筑类型奶牛舍内外气载细菌和真菌数量的变化。选择3种建筑类型的奶牛舍,采用定点采样和平板计数法对舍内、运动场、净道以及场外上风向和下风向处的气载微生物进行同期检测。结果表明:不同建筑类型和不同时间段牛舍内微生物数量均表现出显著性差异(P0.05),气载细菌和真菌总数范围分别为1.7×103~6.9×103和175~483 cfu/m3,通风好的牛舍细菌和真菌总数均较低,且一天中中午的细菌和真菌总数最高。此外,舍内细菌数量显著高于净道和运动场(P0.05),但舍内真菌总数与净道之间未表现出显著性差异(P0.05),仅显著高于运动场;多数牛场外下风向5~50 m处的细菌和真菌总数显著高于上风向处(P0.05)。本研究结果可为奶牛舍环境改善和疾病预防提供参考。     

冬季规模化猪场哺乳母猪舍内有害气体、颗粒物和微生物气溶胶的分布特点

旨在探究冬季猪舍内有害气体、颗粒物和微生物气溶胶的分布规律,为猪场制定有效的环境调控措施提供基础数据和科学依据。本试验在江苏省盐城市某封闭式哺乳母猪舍进行,舍内设立5个监测点(前、中、后、南、北),高度设为距离地面1.0 m处,每30 min自动记录舍内温度和相对湿度,分别于每天6:00、10:00、14:00和18:00测定舍内风速、气体(NH₃,H₂S和CO₂)、不同粒径颗粒物(PM₁₀、PM_2.5、PM₁和PM_0.3)和微生物气溶胶(细菌、真菌和大肠杆菌气溶胶)浓度,每天监测4次,连续监测7 d。结果表明,哺乳母猪舍内平均温度和相对湿度分别为23.2℃和71.8%。舍内平均风速为0.36 m/s,显著低于舍外(1.79 m/s)。舍内NH₃、H₂S和CO₂平均浓度为5.50、0.27和2 214 mg/m³,舍内后部的NH₃     

南方夏季水帘降温系统对发酵床猪舍与传统猪舍空气质量的影响

本文旨在探讨南方夏季高温高湿环境下发酵床猪舍采用水帘降温系统的可行性。试验在发酵床猪舍和传统猪舍同时进行,夏季高温高湿环境下,启用水帘降温系统,试验期63d,监测两栋猪舍内3个区域（A区靠近水帘端、B区猪舍中央、C区靠近风机端）的温湿度分布特点、舍内空气微生物数量和氨气浓度。结果表明,采取水帘降温系统后,发酵床舍温度降低1．79℃～4．23℃,两栋猪舍3个区域温度分布特点相同,即靠近水帘端最低,发酵床猪舍中央比水帘端高0．58℃～1．04℃,风机端比水帘端高1．51℃。2．49℃。发酵床舍内细菌总数和大肠杆菌数均显著高于传统舍（P〈0．05）。发酵床舍与传统舍的舍内氨气浓度分别为（6．56±0．32）mg／m3,（8．55±0．82）mg／m3,差异显著（P〈0．05）。南方夏季发酵床猪舍采取水帘降温后,可以有效降低舍内温度和氨气浓度,但细菌总数和大肠杆菌数均显著高于传统舍,尤其是靠近风机端。     

江淮地区漏缝地板-机械清粪系统羊舍环境检测及评价

为了评价漏缝地板-机械清粪(刮粪板)系统对羊舍小环境的改善效果,首先对羊舍进行改造,将羊舍内部的土坯平地(对照组)改造为高床,并铺设塑料漏缝地板、配备机械刮粪板(试验组)。分别在2013年7月(夏季)和2014年1月(冬季)连续两周对两类羊舍中的温度、相对湿度、氨气(NH3)、甲烷(CH4)、二氧化碳(CO2)浓度进行检测,并对漏缝地板清粪效果、刮粪板运行噪音及运行时山羊的行为变化进行评价。(1)夏、冬两季羊舍外界、对照组、试验组的温度分别为31.3℃、30.7℃、30.0℃和6.4℃、8.7℃、7.2℃。夏季外界与羊舍内温度差异不显著(P0.05),对照组和试验组舍内温度差异不显著(P0.05)。冬季对照组和试验组舍内温度显著高于羊舍外温度(P0.05),对照组和试验组差异不显著(P0.05);(2)夏、冬两季羊舍外界、对照组、试验组舍内相对湿度分别为85.0%、90.1%、88.6%和59.0%、80.4%、74.7%。夏季对照组湿度显著高于舍外(P0.05),试验组湿度与舍外基本一致,显著低于对照组(P0.05);冬季,对照组和试验组舍内湿度均显著高于舍外(P0.05),但试验组舍内湿度显著低于对照组(P0.05);(3)对照组、试验组舍内夏季风速分别为0.17m/s和0.11m/s,冬季风速分别为0.09m/s和0.05m/s。(4)夏季对照组和试验组舍内NH3、CH4和CO2的浓度分别为2.78、183.9、850.8mg/m3和1.58、110.2、640.1mg/m3;冬季对照组和试验组舍内NH3、CH4、CO2、浓度分别为5.76、289.8、2 673 mg/m3和3.54、227.5、1 758 mg/m3,夏、冬两季试验组舍内三种气体浓度均显著低于对照组(P0.05)。本研究表明,漏缝地板-机械清粪系统在山羊集约化养殖中可显著降低羊舍内有害气体浓度,改善养殖小环境。     

宁夏银川地区哺乳期犊牛舍环境因子监测

为研究犊牛舍环境的季节性变化,选取宁夏银川地区有代表性建筑类型的犊牛舍,对四季舍内的环境温度、相对湿度、风速以及二氧化碳、氨气的浓度进行测定。结果显示,犊牛舍内温度范围为-25.6～42.3℃,舍内平均湿度为7.1%～90.3%,舍内风速范围为0～6.77 m/s,氨气浓度范围为0～1.9 mg/m3,二氧化碳浓度范围为182～942 mg/m3;12个月中犊牛出现中度热应激累计34 d,轻度热应激累计55 d;7月20日犊牛舍24 h均处于热应激状态,其中9 h处于中度热应激状态,15 h处于轻度热应激状态;12个月中犊牛舍二氧化碳超标天数为18 d;冬季平均温度为-12℃,犊牛处于不利于生长的冷应激状态。研究表明,宁夏银川地区哺乳期犊牛夏季热应激强度大,冬季冷应激较为普遍,舍内风速过大,二氧化碳浓度超标。建议牛场考虑夏季增加防暑减温措施,冬季增加保暖措施,加强舍内通风换气,以减少有害气体产生,合理调配日粮配方,提高犊牛生产性能。     

内蒙古中部地区2种不同羊舍小气候分析

目前,养羊业的养殖方式逐步由草原放牧转变为规模化、集约化饲养,饲养方式的改变导致羊舍环境质量成为影响羊只健康的一项重要因素。选取集约化舍饲养羊场为研究对象,分别于2015年4月（春季）、8月（夏季）、11月（秋季）和2016年1月（冬季）对2种有窗式自然通风羊舍进行气候环境指标检测并进行比较分析。结果表明,双坡式羊舍年平均温度为9.2℃,钟楼式羊舍年平均温度为9.9℃;双坡式羊舍年平均相对湿度为45.9%,钟楼式羊舍年平均相对湿度为39.2%;双坡式羊舍年平均风速为0.3m/s,钟楼式羊舍年平均风速为0.1 m/s;双坡式羊舍年平均照度为251lx,钟楼式羊舍年平均照度为436 lx;双坡式羊舍年平均噪音强度为52.4 dB,钟楼式羊舍年平均噪音强度为54.8dB。综上表明,双坡式羊舍的年平均相对湿度和年平均风速高于钟楼式羊舍,而钟楼式羊舍的年平均温度、年平均照度和年平均噪音强度均高于双坡式羊舍。     

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