当前肉鸭饲养存在的问题及对策

中国是水禽养殖大国。近年来,由于饲养肉鸭成本比快大肉鸡低,经济效益每只1．5～2元,市场消费量越来越大,使中国肉鸭业得到了快速发展,涌现出一大批肉鸭一条龙企业。但由于制种、防疫工程、饲养设施、疾病和饲养管理技术等方面还存在着诸多问题,直接影响了中国肉鸭业的健康发展。该文较为系统地分析了当前存在的问题,介绍了肉种鸭健康养殖的一些饲养管理技术,为中国今后肉鸭业的健康发展提供了参考。     

四川地震灾区生产应急与恢复技术方案——肉鸭健康饲料与管理技术方案

1．功能与用途。加强肉鸭饲养管理，注重卫生防疫，提高灾后肉鸭养殖生产质量安全水平。2．技术要点（1）饲养管理。实行“全进全出”的饲养制度。雏鸭应来自具有《件禽生产许可证》的父母代种鸭场或专业孵化厂，并经产地防疫部门检疫。雏鸭第一次饮水应该在出壳后24小时，水温在30％左右为宜。饮水3—4小时后即可喂食。肉鸭喂料一般采用自由采食和定期喂食。     

家禽健康养殖营养调控技术研究进展

近年来家禽业在规模化、商业化上得到了很大发展，越来越多的人开始关注行业的安全和可持续发展，健康养殖问题已成为人们关注研究的焦点。健康养殖应该包括饲养条件、选种、疾病控制、饲料营养、饲养管理、产品质量、动物福利、生态系统，以及工作管理等。该文通过国内外相关文献的调查分析，着重阐述了当前阻碍家禽健康养殖可持续发展的主要营养性问题（如动物食品质量安全、饲料安全、环境污染、生态环境恶化、动物源性耐药菌增多等。）及家禽业健康养殖营养调控技术（如禽产品品质的营养调控技术、生态环境的营养调控、饲料配方、添加剂及饲养方式等），指出畜牧业必须主动生产适应人们现代健康安全膳食所需要的畜产品，这是畜牧业可持续发展的关键所在。     

家禽健康养殖营养调控技术研究进展

近年来家禽业在规模化、商业化上得到了很大发展,越来越多的人开始关注行业的安全和可持续发展,健康养殖问题已成为人们关注研究的焦点。健康养殖应该包括饲养条件、选种、疾病控制、饲料营养、饲养管理、产品质量、动物福利、生态系统,以及工作管理等。该义通过国内外相关文献的调查分析,着重阐述了当前阻碍家禽健康养殖可持续发展的主要营养性问题(如动物食品质量安全、饲料安全、环境污染、生态环境恶化、动物源性耐药菌增多等。)及家禽业健康养殖营养调控技术(如禽产品品质的营养调控技术、生态环境的营养调控、饲料配方、添加剂及饲养方式等),指出畜牧业必须主动生产适应人们现代健康安全膳食所需要的畜产品,这是畜牧业可持续发展的关键所在。     

我国奶牛养殖小区生产工艺与工程配套技术体系研究

近年来，中国奶业持续快速发展，作为我国奶牛饲养主体的农村散户小规模饲养已占奶牛总饲养量的80%左右。由于养殖规模小，设备简陋，饲养条件差，疾病难以防控，很多地方试图通过建设奶牛养殖小区来加以解决。但目前我国奶牛养殖小区还没有一套可供实际推广应用的生产工艺模式，小区没有科学的规划布局，工艺技术路线和工程防疫技术不到位，设施设备的配置不合理，饲养方式不统一，管理松散，缺乏计划性和全年生产的均衡一致性，无法从根本上克服这些矛盾。为此，作者在广泛调研的基础上，结合中国国情，提出了一套适合于奶牛养殖小区的舍饲散养生产工艺模式，并就该工艺模式的特点、生产工艺技术路线、工艺技术参数确定、配套设施与设备、小区布局以及工程防疫等关键技术进行了探讨，旨在为推进奶牛养殖小区的规模化、标准化的进程，提升我国奶业生产水平提供参考。     

农村散养鸡疫病防治技术浅析

农村散养鸡的饲养周期长、食物来源丰富、运动量大,具有肉质紧实、味道鲜美的特点,深受城市消费者的青睐,市场前景广阔。但由于散养户的饲养管理水平较低、缺乏疫病防治知识,导致散养鸡疫病发生频繁、死亡率高,严重挫伤了农户养殖积极性。分析农村散养鸡疫病发生原因,介绍了"养殖场地选择、选购健康鸡苗、重视免疫接种、科学饲养管理、病死鸡无害化处理"等散养鸡疫病防治技术要点。     

浅谈梅花鹿的养殖技术及疾病防治

近年来,梅花鹿的养殖规模在贵州省的遵义市、安顺市、黔西南、黔南州等地呈逐年扩大的态势。为降低养殖风险,推动梅花鹿养殖持续健康发展,对梅花鹿养殖技术及养殖过程中的一些常见疾病进行了分析,并提出了相应的饲养管理办法与疾病防治措施,以供广大养殖企业参考。     

猪的舍饲散养清洁生产工艺及其关键技术

积极开展工业化健康养殖模式的研究与产业化示范，对推动养猪业的现代化，实现养猪业的跨越式发展具有极其重要的意义。该文分析了中国养猪业现状及其存在的主要问题，提出了一套融猪的生理、生态、行为、习性于一体的舍饲散养清洁生产工艺模式，并就其技术特点、关键技术内容及其配套设施设备进行了全面介绍。该工艺模式是在充分考虑动物福利的基础上，通过将养猪工艺与节能节水型干清粪方式和动物福利的有机结合，来改善猪的饲养环境条件、增进猪只健康水平、节约水资源、节省人工，使现代养猪生产更赋予自然化、人性化。为提高中国畜禽养殖业工业化发展水平，建立安全、优质、高效、节耗、环境友好型畜禽养殖业技术体系，增强中国畜产品的国际市场竞争能力提供了技术支撑。     

蛋鸡笼养福利问题以及蛋鸡养殖模式

通过关注蛋鸡笼养发展、笼养引起的蛋鸡福利与健康问题，进一步比较了几种蛋鸡养殖模式下蛋鸡福利、生产成本、死亡率以及生产性能的情况，结果表明：不同养殖模式下蛋鸡的福利状况各有优缺点；采用欧盟所推荐的大笼饲养和自由散养蛋鸡时，蛋鸡生产成本分别会增加13％和21％；相比地面平养和自由散养，笼养蛋鸡模式下的蛋鸡死亡率相对较低，生产性能一般较高。从而提出今后我国蛋鸡养殖模式仍将会以笼养为主的观点，并在此基础上提出了一些改善笼养蛋鸡福利可以采取的措施，如笼养方式的选择、合理的鸡笼设计与安装、笼养密度的调整、饲养管理的改进以及环境条件的改善等。     

奶牛养殖小区规划设计研究与探讨

奶源基地建设是我国奶业发展的基础，奶牛养殖小区是目前我国奶牛养殖的可行模式。该文依据目前我国奶牛养殖约有72.7％为农户养殖的现状，立足奶牛养殖小区及其配套设施建设存在的问题，对奶牛养殖小区进行合理规划布局，并提出了奶牛养殖小区建设相应的技术参数，目的在于为奶牛养殖小区建设单位提供参考，改变我国庭院式奶牛饲养方式，提高奶牛饲养管理水平，改善奶源质量。在平面布局上，应该有管理生活区、奶牛生产区、辅助生产区和粪污处理区等4个功能区域。管理生活区和辅助生产区应建在小区的地势较高，上风向处；而粪污处理区设在地势低、下风向处；奶牛生产区设在小区中间。     

“绿色革命”以来大气CO2浓度升高对C3作物营养品质的影响

自20世纪60年代"绿色革命"以来,育种技术和农耕技术的发展促进了农作物产量的大幅提升,然而作物的营养品质出现下降趋势。在相似的遗传背景下,大气CO_2浓度升高会使单位体积农作物产品的营养元素含量下降,因此"绿色革命"至今,农作物产品的营养元素下降可能受大气CO_2浓度升高影响。通过植物生长箱模拟"绿色革命"初期和目前的大气CO_2浓度水平(310μmol/mol和400μmol/mol),针对主要C_3作物水稻、小麦和大豆,研究"绿色革命"以来大气CO_2浓度升高对其籽粒的C、N、Fe、Zn元素含量的影响,结果表明:CO_2浓度升高对3种作物籽粒的C元素含量几乎没有影响,变化幅度在±1.5%之间;籽粒的N、Fe、Zn元素含量普遍呈现下降趋势,但均未达到显著水平。     

Potential of wild species for genetic enhancement of some semi-arid food crops

Discovery and incorporation of genes from wild species provide means to sustain crop improvement, particularly when levels of resistance in the cultigens are low and virulent strains of pests and pathogens overcome the host plant resistance. The extent of utilization and the potential of the wild genepool for genetic enhancement were reviewed in five important food crops viz. sorghum, pearl millet, chickpea, pigeonpea and groundnut grown in the semi-arid tropics. Introgression from compatible wild germplasm in the primary gene pool resulted in transfer of new cytoplasmic male sterility systems in pearl millet and pigeonpea, development of high protein, cleistogamous flower and dwarf pigeonpea lines and foliar disease resistant groundnut cultivars. Utilization of wild species in secondary and tertiary gene pools has been generally limited due to sterility, restricted recombination or cross incompatibility. Nevertheless, these species are extremely important as they contain high levels of resistance to several important biotic and abiotic stresses. Several of them, like those belonging to the Parasorghum section and the rhizomatous Arachis species are sources of multiple resistances and hold great promise to sustain crop productivity.     

Faculty positions:Center for Agricultural Resources Research,Chinese Academy of Sciences

正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications     

Soil-profile distribution of primary and secondary plant-available nutrients under conventional and no tillage

Nutrient distributions under no tillage (NT) compared with conventional disk-and-bed tillage (CT) management in the warm, humid region of the southeastern USA need to be assessed so that future placement, quantity, and type of fertilizers can be altered, if necessary, to efficiently match crop demands. We determined soil-profile distributions of pH, N, P, S, K, Ca, Mg, Na, Zn, Fe, Mn, and Cu to a depth of 0.9 m at the end of 8.5 years of continuous CT and NT management on a Weswood silty clay loam (fine, mixed, thermic Fluventic Ustochrept) in southcentral Texas. Most dramatic changes occurred within the 0–0.05 m depth, where soil under NT had lower pH, Fe, and Cu than under CT, but greater P, K, Zn, and Mn. Greater P and K under NT than under CT also occurred below the till-zone (0.15–0.3 m). At a depth of 0–0.3 m, soil under NT contained greater amounts of extractable P, K, Zn, Fe, Mn, and Cu than under CT. Nitrogen fertilization had little effect on nutrient distributions, except resulting in greater extractable K at 0–0.05 m and greater nitrate at 0–0.15 m. Few changes in soil-profile distributions were observed for extractable S, Ca, Mg, and Na. Long-term continuous use of NT on this fine-textured, high-fertility (except for N) soil had no apparent adverse effects on nutrient distributions relative to CT, but enhanced conservation and availability of P, K, Zn, Fe, Mn, and Cu near the soil surface where crop roots proliferate.     

Assessing the effectiveness of conservation measures: Resolving the “wicked” problem of the Steller sea lion

“Wicked” problems are those that are complex and that change when solutions are applied. Many conflicts in conservation fall into this category. The study approached the problem of how to constrain the apparent wickedness of a problem in the conservation management of a species by using simple empirical indicators to carry out iterative assessment of the risk to a population and to document how this risk evolves in relation to the addition of new data and the implementation of management actions. Effects of high levels of uncertainty within data and also concerning population structure were examined through stochastic simulation and by exploration of scenarios. Historical trends in the example used, the Steller sea lion, showed rapid declines in abundance in some regions during the 1980s. The current total population is 130,000-150,000 Steller sea lions through Alaska and British Columbia and this number has been stable since about 1990 in spite of regional differences in population dynamics. Regional differences in the sequence of changes in the number of pups and non-pups, suggested that an internal re-distribution of juveniles could have happened between 1980 and 1990. Current productivity also appears close to the long-term mean. Stochastic population projection using various scenarios showed that, based upon this history, the risk of extinction for the population has declined and is below reasonable thresholds for considering the population to be endangered. The trends in risk suggest that management actions taken since 1990 have probably been effective. Consequently, the conservation management objectives for the Steller sea lion are probably being met. The approach provides a mechanism, based upon experience and scenario analysis, for exploring future policy options and may help to constrain the debate amongst stakeholders about the cost-benefit trade-offs associated with different options.     

Collection and preliminary evaluation of native turfgrass accessions in Italy

Despite a raising interest on turfs in Italy, all theavailable varieties of this kind in the Country are of foreign origin, and areoften poorly adapted to the prevailing climatic conditions. This prompted tobegin a collection activity of indigenous turfgrass species, with the ultimategoal of identifying promising materials for future breeding based on localgenetic resources. The collection was carried out in three areas of Italy, viz.the northern Po Plain, the coastal region of Liguria, and the island of Sardiniathat are characterised, respectively, by subcontinental, warm temperate, andtypical Mediterranean climate. Altogether, 141 sites were visited, yielding 226accessions belonging to eight species of potential interest for turfs:Poa pratensis, Poa trivialis,Festuca rubra, Festuca arundinacea,Lolium perenne, Agrostis stolonifera,Agrostis tenuis, and Cynodon dactylon,this last being a warm-season grass. Poa pratensis andCynodon dactylon were mostly collected in northern Italyand Sardinia, respectively, whereas Festuca arundinacea andLolium perenne were rather ubiquitous. The collection sitesranged from 0 to 1040 m asl, but sites over 750 m wereonly visited in the inner part of Sardinia. All the accessions, collected aswhole plants, were transplanted at Lodi, northern Italy, where they are beingevaluated. Their preliminary evaluation for traits of importance for turf use,such as sward colour and overall quality, highlighted the great variation andthe occurrence of interesting accessions in all species. Other characters wererecorded, bearing specific importance in individual species, and in all casespromising accessions were identified. The germplasm of Festucarubra, Festuca arundinacea, and Loliumperenne proved highly infected by endophytic (symbiotic) fungi of thegenus Neotyphodium.     

Enhanced establishment and growth of giant cardon cactus in an eroded field in the Sonoran Desert using native legume trees as nurse plants aided by plant growth-promoting microorganisms and compost

To evaluate the feasibility of long-term desert reforestation technology of mixed vegetation, cardon cactus (Pachycereus pringlei) seedlings from indoor and outdoor nurseries were planted in the field adjacent to one seedling of potential legume nurse trees: mesquite amargo (Prosopis articulata), yellow palo verde (Parkinsonia microphylla), and blue palo verde (Parkinsonia florida). Some of the planting holes were also supplemented with common dairy compost. Additionally, the combinations of legume tree–cactus were inoculated with either a consortium of desert arbuscular mycorrhizal (AM) fungi, plant growth promoting bacteria (PGPB; the diazotroph Azospirillum brasilense Cd, and the phosphate solubilizer Paenibacillus sp.), or a mixture of all. The field experiments were evaluated periodically during 30 months for survival and growth. Cardons reared in an outdoor screen house survived better in the field than those reared in a controlled growth chamber and hardened later outdoors. Association with any legume nurse tree increased survival and enhanced growth of untreated cardons. For cardons growing alone, application of either compost, AM fungi, and all the treatments combined increased survival. For these plants, no treatment affected plant growth during the first 3 months after transplanting. Later, all treatments, except for AM fungi, enhanced plant growth. However, only 2 years after transplanting the enhanced growth effect of AM fungi was also significant. In the presence of the legume nurse trees, transient positive effects on cardon growth were recorded. General evaluation after 30 months of cultivation showed that the treatments positively affected cardon growth when growing alone or in combination only with mesquite amargo but not with the other two legume trees. This study proposes that young legume trees have the capacity to enhance survival and growth of cardon cactus, depending on the legume cactus combination. Additional treatments such as compost or PGPB can either amplify the effect or else attenuate it.     

Karyotypic and genome size variation in Cajanus cajan (L.) Millsp. (pigeonpea) and some wild relatives

Detailed karyotypes and 4C DNA amounts have been studied in five cultivars of Cajanus cajan and 20 species belonging to Cajanus, Rhynchosia, Dunbaria, Flemingia and Paracalyx. C. cajan shows intraspecific variability and its karyotype is most similar to that of C. cajanifolius (sect. Cajanus) in the morphology and number of satellite chromosomes and the lack of any correlation between chromosome size within the complement and asymmetry. Karyotypes of C. lineatus and C. sericeus belonging to sect. Atylia are similar with respect to maximum r-index and the ratio of longest and shortest chromosomes in their respective complements. C. acutifolius (sect. Frutocosa) is distinct in having a very low ratio (1.44) between the longest and the shortest chromosomes, while in C. albicans, C. goensis, C. scarabaeoides (sect. Cantharospermum) there is no chromosome pair with r-index >2.0. C. mollis and C. volubilis (sect. Volubilis) show similarity with regard to ratio between the longest and the shortest chromosomes and a distinct chromosome pair with an arm ratio of 2.7 and C. platycarpus is distinct (sect. Rhynchosoides) in having the smallest ratio (1.36) between the longest and the shortest chromosomes. 4C DNA amounts in Cajanus and Rhynchosia vary between 3.28 pg to 11.69 pg and 4.92 pg to 11.13 pg respectively, while in Dunbaria, Flemingia and Paracalyx these vary between 4.70 and 7:06 pg. In the genus Cajanus karyotypic features and 4C DNA amounts agree with the sectional classification and bring out a close relationship between C. cajan and C. cajanifolius. This is supported by studies based on seed protein patterns, isozyme analysis, trypsin and chymotrypsin inhibitor patterns, RFLP and RAPD data and crossability relationships. A clear relation between DNA amount and abnormalities effecting the extent of pairing and recombination in interspecific hybrids shows the importance of this study in developing future breeding programme involving C. cajan and its wild relatives that are of potential value.     

Effect of some fungicide seed treatments on the survival of Bradyrhizobium japonicum and on the nodulation and yield of soybean [Glycine max. (L) Merr.]

Several commercial fungicide seed treatments were evaluated for their possible effect on the survival of Bradyrhizobium japonicum on seeds and on the nodulation and yield of soybeans in a greenhouse and a field experiment. quinolate Pro (carbendazim and oxine copper), Vitavax 200FF (carboxin and thiram), and Monceren (pencycuron) had a small effect or no effect on the survival of B. japonicum and on the nodulation and yield of soybeans. They can thus be considered compatible with soybean seed inoculation. Germipro UFB (carbendazim and iprodione), Apron 35J (metalaxyl), and Tachigaren (hymexazol) decreased B. japonicum survival and the nodulation and yield of soybeans and thus cannot be considered compatible with soybean seed inoculation.     

Leaf position and genotype differences for mineral element concentrations in sorghum grown on tropical acid soil 1

Mineral element deficiencies and toxicities are common problems associated with sorghum [Sorghum bicolor (L.) Moench] production on acid soils. To better understand some of the mineral element problems and the analysis of plant tissue of sorghum plants grown on acid soils, four sorghum genotypes were grown on an acid Oxisol at Carimagua, Colombia limed with dolomite at 2 and 6 Mg ha^‐1.

Samples for mineral element analyses were obtained from leaves at different positions on the four genotypes. Concentrations of P and Mg were highest in the flag leaf (Leaf No. 1) and decreased as the position on the plant declined from the top of the plant for plants grown at 2 Mg lime ha^‐1. Similar decreases in P, Mg, K, and Zn concentrations occurred in plants grown with 6 Mg lime ha^‐1. Concentrations of Ca, S, Si, Mn, Fe, Cu, and Al increased as leaf position declined from the flag leaf for plants grown at 2 and 6 Mg lime ha^‐1. The higher lime supply enhanced Ca and reduced Mn and Fe concentrations in leaves. Differences in mineral element concentrations for the four genotypes used were fairly extensive. The elements to show the greatest range among genotypes were Al and Si and the elements to show the least range among genotypes were P, K, and S. Care should be used in collecting leaf samples for plant analysis and genotypic differences for accumulation of mineral elements should be considered in interpretation of results.