夏季鸡舍纵向通风系统的应用与研究

本文介绍了在我国各地不同类型鸡舍内纵向通风系统的应用情况;分析了湿垫蒸发降温对我国各地气候的适应性。实际应用结果表明:纵向通风结合湿垫降温系统可将我国各地的不同类型鸡舍的夏季气温基本控制在28～30℃以下,舍内气流速度可达1.0～2.0m/s,气流分布均匀,可为鸡群提供100％的新鲜空气;一般,夏季蛋鸡和种鸡的产蛋率可提高5％以上,饲养密度可提高10％～20％,制止了高温应激死鸡;且较传统的横向通风节约电能和运行费用达40％以上。     

鸡舍纵向通风

该文论述鸡舍纵向通风的机理、实践效果及实现鸡舍纵向通风的技术关键。     

鸡舍纵向通风系统设计与应用中的几个问题

针对当前我国在原密闭式鸡舍的横向通风与开放式或半开放式鸡舍的自然通风方式改造成纵向通风过程中存在的一些问题,着重分析讨论了鸡舍纵向通风系统的通风换气量与舍内风速取值,进气口面积与位置的确定,风机的选型及其不同季节的运行管理等问题。为今后我国不同类型鸡舍的纵向通风系统的设计与应用提供参考。     

Comparison of biological and chemical methods to predict nitrogen mineralization in animal wastes

Summary Biological and chemical methods to predict the level of plant-available N in animal manure were investigated under laboratory and growth-chamber conditions. Two biological methods (maize cultivation in pots and incubation of soil-waste mixtures) and four chemical methods (N extraction by autoclaving, 0.5 N KMnO₄, pepsin, and 6 N HCl) were compared for their accuracy in determining the availability of N in 10 samples of animal manure applied to soil. The autoclaving, permanganate, and pepsin methods were able to predict N availability in this group of wastes. Total N mineralized in a soil amended with different samples of animal manure ranged from 0 to 311 mg N kg^-1 soil. Expressed as a percentage of organic N added to the soil, mineralized N range from 0 to 39%. The poultry manure samples gave higher mineralization rates than the other types of manure tested. In general, mineralized N became immobilized during the incubation process, except for the second poultry manure sample, which showed an initially rapid then a a slow release of mineral N, and pig manure sample 2, which showed a slow initial rate, followed by a rapid increase, and then a slow rate of N release. The first-order exponential model used was able to describe the pattern of N mineralization in pig manure sample 2, poultry manure sample 2 but not the other samples.     

我国畜禽养殖业污染防治对策

简述了我国畜禽养殖业环境污染主要危害及其防治存在的主要问题 ,并提出污染防治对策 ,即借鉴发达国家畜禽养殖业环境管理经验 ,以减量化、无害化及实用廉价为原则 ,合理规划 ,综合防治 ,建立畜禽养殖业污染物处理最佳模式。     

A survey of the production and use of animal manures in England and Wales

Abstract. A survey of manure management practice was undertaken in 1996, by postal questionnaire submitted to a stratified sample of egg and broiler producers in England and Wales. Out of a target of 500 laying hen and 500 broiler (chickens produced for meat) production units in the survey sample, 356 (36%) returned questionnaires. The survey provided information on amount and type of manure production, manure storage and land application strategies (timing, techniques and awareness of nutrient content). Within the survey, no attempt was made to differentiate between organic and conventional production systems. About 45% of manure production was estimated to come from layer holdings, 55% from broiler litter. It was estimated that 70% of the national manure production is litter‐based and about 30% are droppings collected without litter. Sawdust/shavings are the most popular bedding material, with an average final depth of 100 mm for broilers and 140 mm on litter‐based layer units. Commonly, storage is available within housing for at least the length of the cropping cycle (6 weeks in broiler production, or 12 months in deep pit laying houses), around 60% of poultry manure is stored for a period following removal from the house, most commonly for 3‐6 months. Overall, autumn was the peak period for manure spreading, with over 40% of laying hen manure and 50% of broiler manure applied at that time. On grassland, spreading was reasonably evenly distributed throughout the year but autumn application was favoured for arable crops, especially before the establishment of cereals and root crops, overall, almost 50% of layer and broiler manure was applied in the autumn. In the survey, up to 10% of manures were claimed to be incorporated within a day of application and about 60% within a week of application, presumably because of concern about odour nuisance. Around 25% of poultry manure was applied by contractors. A high proportion of farmers (c. 40% with layers, c. 60% with broilers) exported manures from their holdings, the proportion removed amounting to almost 90% on these farms. Although evidence elsewhere indicates that farmers make little allowance for manures in planning crop fertilizer inputs, the survey responses suggested that farmers do make an effort to allow for manures but that their confidence in the advice available to them is lacking, or they may have other technical reasons for not taking advantage of the manurial value. Information provided by the survey is of significant importance to policy makers (e.g. for the construction of environmental emissions inventories), researchers, consultants and farmers.     

Soil compaction and poultry litter effects on factors affecting nitrogen availability in a claypan soil

Soil compaction may affect N mineralization and the subsequent fate of N in agroecosystems. Laboratory incubation and field experiments were conducted to determine the effects of surface soil compaction on soil N mineralization in a claypan soil amended with poultry litter (i.e., Turkey excrement mixed with pine shavings as bedding). In a laboratory study, soil from the surface horizon of a Mexico silt loam soil was compacted to four bulk density levels (1.2, 1.4, 1.6 and 1.8 Mg m⁻³) with and without poultry litter and incubated at 25 °C for 42 days. A field trial planted to corn (Zea mays L.) was also conducted in 2002 on a Mexico silt loam claypan soil in North Central Missouri. Soil was amended with litter (0 and 19 Mg ha⁻¹) and left uncompacted or uniformly compacted. Soil compaction decreased soil inorganic N by a maximum of 1.8 times in the laboratory study; this effect was also observed at all depths of the field trial. Compacted soil with a litter amendment accumulated NH₄⁺-N up to 7.2 times higher than the noncompacted, litter-amended soil until Day 28 of the laboratory incubation and in the beginning of the growing season of the field study. Ammonium accumulation may have been due to decreased soil aeration under compacted conditions. Application of litter increased soil N mineralization throughout the growing season. In the laboratory study, soil inorganic N in unamended soil was negatively correlated with soil bulk density and the proportion of soil micropores, but was positively related with soil total porosity and the proportion of soil macropores. These results indicate that soil compaction, litter application and climate are interrelated in their influences on soil N mineralization in agroecosystems.     

National Animal Identification System: Fancier Perspective

With respect to the National Animal Identification System (NAIS), poultry science professors are key players in resolving the concerns of fanciers in every state, because they have been and will be involved in developing the plans to implement the NAIS in their state. Highly restrictive, financially prohibitive regulations that ignore the needs of standard-bred exhibition poultry will cripple and then destroy an important part of our nation's poultry industry. This applies not only to NAIS but also to other regulations that affect the testing and movement of poultry. For example, poultry from other states entered in any fair or club poultry show in Texas must have been tested for avian influenza within 30 d of the entry date. This has eliminated entries from outside Texas, because there are very few veterinarians in Texas and other states that are qualified to test and retest the birds and provide the necessary health papers. We cannot host an American Poultry Association (APA) district meet in our 5-state district number 7 much less be considered for an APA national show. We recommend that any flock participating in the National Poultry Improvement Plan program should be considered adequately monitored and should be allowed into any state that is not under quarantine. Even if the recommendation stated above is adopted, it will not help producers in a state such as Texas, which does not allow fanciers to become part of the National Poultry Improvement Plan. Texas fanciers go to Louisiana, Arkansas, Oklahoma, and New Mexico for exhibitions, but exhibitors from those states have been effectively eliminated from Texas shows. Anything that poultry science specialists can do to help prevent or change regulations detrimental to exhibition poultry is greatly needed and appreciated. The leadership of the APA and the American Bantam Association agrees with the NAIS and are actively involved in defining a plan that accomplishes program goals but does not cripple or end their contribution to the poultry industry. Furthermore, we urge our members to comply with the laws and regulations affecting poultry. There is no reason that commercial poultry and standard-bred exhibition poultry cannot exist side by side if both groups, in conjunction with the proper authorities, work together for their mutual benefit. These organizations are committed to that goal!     

光照在养鸡生产中的作用

光照在养鸡生产中有着十分重要的作用 ,就光照对性成熟的影响 ,光照在蛋鸡、肉鸡生产中的作用 ,光照强度、光色、光照对免疫的影响进行论述     

Sero prevalences to three diseases in village chickens in Benin

Seroprevalences to three infectious agents were studied in rural poultry farms in three different ecological regions in Benin. Of 260 sera, 65% were seropositive for Newcastle disease virus, 10% for Salmonella pullorum and 62% for Mycoplasma gallisepticum.