新型"中型开放回流呼吸测热装置"研制报告

为满足畜禽能量物质代谢科研领域进一步深入发展要求,对国际上已被广泛应用的传统"开放回流"呼吸测热装置进行了工艺技术改进,于2005年自行设计并采用国产有关仪器仪表和自行加工等部件,研制组装一台技术工艺较为先进的中型开放回流呼吸测热装置。采用电动系统(各种传感器)与微机相结合的方法,使该装置基本达到全部自动控制水平。可以测得在实验期间全程(在线)或各不同阶段(单项)的气体交换及能量代谢等多项内容指标与结果。     

Farmer’s views and values to focus on cattle conservation policies: the case of eight European countries

Our aim was to identify elements useful in designing policies and programmes for conservation of farm animal genetic resources, taking as case study a group of European local cattle breeds. We first investigated the implications of differences among countries in the policies and programmes to be developed. Secondly, we analysed key elements common to countries, which may affect local breed viability. We used the herd size trend expected by the farmer in the near future as an indicator of breed viability. Fifteen breeds, for a total of 355 farms, were surveyed. To take into account the multiple factors influencing breeds’ demographic trends, the questionnaire included economical, technical and social aspects. Among the major differences across countries was the perception of the farmer on the value attributed to the local breed by society. Concerning the elements common to countries and their association to breed viability, the greater the collaboration among farmers and the stakeholders’ appreciation as perceived by the farmer, the greater the viability of the farm. An opposite trend was observed for the age of the farmer. Older farmers generally planned to soon cease farming or decrease herd size, whereas young farmers planned to increase the size of their herds. Implications of including these elements in conservation polices are discussed.     

雉鸡育成后期能量代谢参数及其需要量的研究

采用梯度饲养试验、代谢试验和比较屠宰试验 ,结合营养化验和统计分析 ,对 9～ 14周龄育成后期雉鸡的能量代谢参数及能量需要量进行了全面测定研究。结果表明 ,雉鸡育成后期维持代谢能需要量为每千克代谢体重每天 4 6 2 0 0kJ ;雉鸡育成后期生长代谢能的利用效率 (Kpf)为 4 2 18% ,每克增重需要代谢能2 2 86kJ;雉鸡育成后期随着采食量的增加 ,其体蛋白能沉积量、体脂肪能沉积量和体脂肪沉积能占总净能的比例均相应提高 ,但体蛋白沉积能占总净能的比例随着采食量的增加而逐渐降低     

不同能量物质对泌乳奶牛产奶性能的影响

本文探讨了不同能量补充物质对泌乳奶牛生产的影响。,以麸皮作对照,用全棉籽、膨化全脂大豆和脂肪酸钙作为能量补充物质,35d试验结果显示,奶牛产奶量分别提高了6．7％、14．4％和18．2％．．乳脂肪分别提高19．（／9％、11．82％和11．21％、经济效益分别比对照组提高4．20、5．36和8．72．＇L／（头·d）!试验表明,全棉籽、膨化全脂大豆和脂肪酸钙作为能量补充物质,可减轻夏季热应激,提高牛奶产量和牛奶品质,尤以脂肪酸钙效果最佳。     

日照时长对青海湖草地能量平衡的影响

基于青海湖东北部的西海镇环境梯度监测系统9月上中旬的观测数据,利用波文比法计算感热和潜热通量,得到2种极端日照时长和3种日照时长条件下的能量平衡,方差分析和多重比较（LSD法）证明,不同日照条件下能量平衡存在明显差异,表明用日照时长模拟太阳辐射能具有一定的可行性。日照条件对能量平衡的影响主要体现在峰值大小、峰值出现时间、地-气交换形式等方面,峰值随日照时长增加而增大,其他方面要分情况、分时段具体分析。     

“以畜控草”与新疆草畜平衡管理的探讨

长期以来,社会各界及业内都把"以草定畜"视为对天然草地放牧管理与生态保护和建设的终极目标,"以草定畜"似乎已被广泛认同,但是,在草原牧区实现"以草定畜"依然任重道远。在新疆天山北坡,同地带、同一类型的山地草甸草地,在夏季与冬季两种不同放牧利用制度下,植被成分差异显著,在冬季放牧利用制度下,山地草甸草地植被成分中,阔叶杂类草及小灌木明显增多,牧草再生性减弱;而在夏季放牧利用制度下,植被成分中小杂类草与禾本科牧草明显增多,牧草再生性增强;在降水量较丰富的中山带,禁牧封育2～3年后,植被成分中饲用价值低、家畜不宜采食的粗大杂类草明显增多。"以畜控草"应该成为更加积极的草地管理态度和方式。在目前天然草地放牧量难以较大幅度减控的情况下,通过"以畜控草",可以既保持草地植被健康状况又有利于草原畜牧业的发展,这对于实施牧民定居与冷季舍饲的新疆草原牧区,具有极为重要的现实意义。     

Sequence and process of species selection by cattle in relation to optimal foraging theory on an old land in the Natal Sour Sandveld

The sequence in which cattle grazed four grass species during a grazing period was monitored at four stages through the grazing season. Data collected revealed that: (i) species could be classed as being of preferred, avoided or intermediate acceptability, (ii) grazing of classes always proceeded in a set sequence; cattle first grazed preferred, then intermediate classes but largely resisted grazing avoided species, (iii) classes were grazed at different rates through the grazing period, (iv) utilization of intermediate and avoided classes was largely dependent on the extent of grazing of preferred species and exhibited a threshold relationship and (v) observed trends were in general agreement with those predicted on the basis of optimal foraging theory. The data suggests that non‐selective grazing systems may be based upon faulty grazing philosophy.     

草畜优化条件下草地生态载畜量测算方法新探

 结合前人对天然草地载畜量的研究,在草畜优化条件下,归纳总结出“生态载畜量”这一新的测算方法来适应生产发展的需要。在农牧民经济发展和保护草原生态环境之间找到一个草地载畜量平衡点。新的测算方法为草地畜牧业可持续发展提供了理论依据。     

多效唑对草坪草天堂419生长调节作用的初步研究

本试验用新型植物生长延缓剂多效唑配制成０ｐｐｍ,１００ｐｐｍ,２００ｐｐｍ,３００ｐｐｍ,４０ｐｐｍ５种不同浓度的溶液,叶面喷施草坪草天堂,４１９,每次间隔２周,系统观测喷施后草坪划的生长速度,叶片大小,叶色和分蘖状况,结果表明,施用多效唑后草坪不仅叶面积更窄小,绿色更深,分蘖更多而且共生长速度也变小了,但是多效唑溶液浓度超过３００ｐｐｍ时,草坪草生长停滞,叶先变紫红后枯萎死亡。     

全球变暖对高寒冻土区温室气体通量影响研究进展

泛北极地区和青藏高原是陆地生态系统重要的有机碳、氮库。在气候变暖驱动下,高纬度或高海拔冻土融化加速,冻土活动层冻融格局改变,土壤有机质分解增加,成为全球重要的温室气体排放源,其对气候变化的“正反馈”效应受到越来越多关注。本文重点综述了近年泛北极和青藏高原冻土区土壤CO₂,CH₄和N₂O三种主要温室气体通量对冻土退化及冻融作用的响应特征和影响机制,探讨了高寒地区生态系统净温室效应与气候变暖的相互关系,并简要提出了目前冻土区土壤碳排放和氮转化关键过程研究中需要加强的方面,旨在为继续深入开展气候变化背景下冻土碳氮循环研究提供参考。     

春制越年蚕种当年检疫家蚕微粒子病的试验初报

为了有利于蚕业生产上及时、有序地供应无毒蚕种,探究了春制越年一代杂交种在冬季浴消之前将滞育卵进行冷藏浸酸处理,对孵化蚁蚕进行家蚕微粒子病检疫的可行性。采用该方法从抽样107个批次越年蚕种样本(7 g/批)冷藏浸酸孵化的蚁蚕中检出7个带毒批次,并且与同批次的母蛾及常规成品卵家蚕微粒子病检疫结果一致。依据试验结果初步认为,应用此方法可以提前数月开展春制越年蚕种成品卵家蚕微粒子病检疫。     

A long term study of the health status and performance of sows on different feed allowances during late pregnancy. I. Clinical observations, with special reference to agalactia post partum

Thirty nine pairs of full sibs were investigated over 6 parities in a long term study on the effects of late pregnancy feed allowance on the occurrence of agalactia post partum and on the performance of sows and piglets. A careful examination of all sows with a rectal temperature exceeding 39.5 degrees C was performed by a veterinarian within the first 48 h after farrowing. Milk-samples were taken from sows with elevated rectal temperatures and showing clinical symptoms of agalactia. During the last 15 days of gestation the sows in the control group were fed 3.4 kg daily and the sows in the experimental group 1.0 kg daily of a commercial type of diet. In 26.6% of the farrowings in the control group the sows were agalactic whereas the corresponding figure in the experimental group was 14.4%. On clinical examination udder changes were observed in a majority of the diseased sows in both groups. However, the agalactic sows in the control group were generally more affected, with lower water and feed consumption than in the experimental group. No effects of age of the sow (parity number) or length of the gestation period on the incidence of agalactia were demonstrated. The rectal temperature of agalactic sows was significantly higher than in the healthy sows already 1 day before farrowing. The agalactic sows farrowed a larger number of stillborn piglets, which indicates an early establishment of the disease. The number of weaned piglets at 6 weeks did not differ between agalactic and healthy animals. The interval from weaning to first oestrus was not influenced by agalactia in the preceding lactation.