规模化猪场控制环境污染的综合措施

规模化猪场必须注重控制环境污染,本文从养殖模式、饲料及添加剂应用、饲养管理、废弃物处理应用、兽药残留监测五个方面做了综合论述,旨在为生产实践中规模化猪场有效控环境污染提供参考。     

规模化猪场粪污处理技术探讨

目前我国养猪模式正在由各家各户的散养模式向规模化、集约化模式转变.但规模化生猪养殖会产生大量的粪尿和废弃物,这些粪污随意排放会给养殖场周围环境造成严重影响,其已经成为制约规模化养猪产业健康发展的主要因素.在日益强调保护生态环境的今天,猪场粪污处理已成我国养猪业发展的"瓶颈",妥善提高猪场粪污的综合治理,解决环境污染问题,已是现在生态环境保护的重要课题.     

浅谈规模化猪场生物安全综合防控体系的构建要点

随着我国养猪业规模化和集约化程度的不断提高,猪场疫病及环境污染问题日趋呈现严重化和复杂化态势.规模化猪场构建科学规范的生物安全综合防控体系是有效解决猪场疫病发生、环境污染及经济效益下滑的重要举措.本文从养猪场的场址选择、规划布局、引种检疫、消毒工作、免疫程序、废弃物无害化处理等方面入手,阐述了规模化猪场生物安全综合防控...     

大中型猪场固体废弃物资源化利用关键技术

随着养猪业的迅速发展,大中型猪场废弃物的排放是当今畜牧业环境污染的最突出问题,给生态环境造成极大破坏。因此,对猪场固体废弃物的资源化利用是规模化生产与发展急需解决的问题。笔者针对龙山猪场固体废弃物的收集、发酵和加工等关键技术进行研究,旨在为当地大中型猪场废弃物的处理提供参考。     

规模化猪场粪污处理利用模式解析

随着经济社会的发展,我国的养猪场的数量和规模不断扩大,我国生猪出栏量约占全球生猪出栏量的50%,2018全国生猪出栏69 382万头,产量大,粪污等废弃物排放也相应增大,因此,对规模化猪场粪污的有效处理与利用也成为养猪户迫切需要解决的难题。文章综述了规模化猪场粪污的来源及其处理利用模式。     

现代化规模养猪场除臭技术简述

我国是一个生猪养殖大国,其养殖数量位居世界首位。随着养猪规模化、集团化高度发展,虽然当前养殖废弃物等污物得到较为有效处理及循环利用,但在养殖过程中产生的氨、硫化氢等危害动物和人类的臭气,仍未得到较为有效处理。本文主要围绕现代规模化生猪养殖,就开展猪场除臭的意义、必要性、臭气的主要成分和来源以及从养殖源头减排、过程控制和末端处理臭气技术进行简要叙述,为今后规模化猪场开展养殖除臭提供理论参考和技术借鉴。     

规模化猪场粪污处理模式探讨

生猪养殖给我国日常生活带来大量的高品质肉制品,但是规模化生猪养殖会产生大量的粪尿和废弃物,这些粪污随意排放会给养殖场周围环境造成严重影响,其已经成为制约规模化养猪产业健康发展的主要因素。粪便和污水是放错位置的珍贵生产材料,其中富含多种营养物质,在农业生产方面发挥着十分重要的作用。笔者主要结合实际情况,就规模化猪场粪污处理模式进行了分析,希望通过本次研究对更好的提升猪场粪污处理效率有一定帮助。     

生态循环中小规模猪场设计

<正>随着经济发展和人民生活水平的提高,全国各地的生猪饲养得到了迅猛的发展,规模化、标准化、产业化程度逐年提高,特别是近年来在国家生猪扶持政策的鼓励下,各地中小规模化猪场逐渐增多,但这些猪场普遍存在经济效益差或亏损的情况,其因素很多。其中一点是猪场设计不科学,致使生产过程中产生大量有机废弃物且不能有效处理,猪     

规模猪场生态循环模式的研究与建设实践

我国是世界第一养猪大国,随着规模化程度的提高,猪场废弃物所产生的环保问题日益加剧,规模化猪场迫切需要通过有效的治理途径,解决猪场废弃物的环境污染问题。生态循环种养模式是解决规模猪场环境污染的必由之路。本文在分析了生态循环模式的意义、当前国内外研究现状、存在的共性问题等基础上,介绍了生态循环模式的建设实践。     

规模化猪场“猪-沼-渔-作物”处理模式的研究与应用

规模化养猪场有机废弃物的“减量化、无害化、资源化”处理与利用,是促进养殖业健康发展,倡导循环经济的重要举措。本文研究了规模猪场有机废弃物“猪-沼-渔-作物”处理模式的效果,探讨评价了该技术模式的经济生态效益。     

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