The effects of anthelmintic treatments against gastrointestinal nematodes on the performance of breeding ewes and lambs on pasture in semi-arid Kenya

The effects of anthelmintics treatments in controlling gastrointestinal nematodes in breeding ewes in a semi-arid area of Kenya were determined. The study carried out during two breeding seasons, between June 2000 and December 2001 where albendazole was administered to groups of ewes, 2 weeks before mating, 3 weeks to lambing and mid lactation indicated significantly lower nematode egg counts in treated than untreated groups of ewes. In the first breeding season, reduced rainfall resulted in pasture scarcity and weight loss in both groups of ewes through out the gestation period, but losses were higher for the untreated group. In the second season, both groups of ewes showed a steady increase in weight gain during the gestation period and post-partum, but weight gains were higher in the treated group. In lambs, weight gains at 6 weeks were higher for treated ewes than control groups, in both breeding seasons. The results of this trial indicate that anthelmintic treatments in breeding ewes in the study area are beneficial in reducing gastrointestinal nematode infections and improving performance of the ewes and their lambs. In addition to the treatments, breeding ewes should be given feed supplementation particularly during periods of pasture scarcity.     

不同氮肥施用量对青贮玉米喂羊效果的影响

玉米品种白马牙经追施不同量的氮肥（0、150、300kg尿素／hm^2），收割后制成青贮玉米的CP含量就会不同，用该青贮玉米饲喂育成羊，观测增重情况．结果显示，施尿素300kg／hm^2组的增重显著（P〈0．05），平均日增重是136．9g，高于未施尿素的对照组，提高幅度达26．10％．     

26种木莲属植物的园林观赏价值评价*

采用层次分析和加权评分相结合的评价系统,以木莲属植物的园林景观应用为目的,根据观赏价值、资源潜力、生物学特性三大类13个指标,对26种木莲属植物的园林观赏价值进行评价。筛选出适宜华南地区园林应用的种类,有亮叶木莲、马关木莲、木莲、大叶木莲、海南木莲、毛桃木莲、乳源木莲、大果木莲等,评价结果与实际情况较为一致。此评价可以为育种目标的确定和育种亲本的选配提供依据,还可以很好地了解木莲属各个种的优缺点,为建立木莲属园林植物核心种质资源库提供数据支持,也便于人们根据各自的目标进行选择。     

不同辐照剂量处理对龙眼果实贮藏期和果实品质的影响

[目的]为研究"辐照+低温冷藏"处理对龙眼鲜果贮藏期及其对果实品质变化的影响,以期达到延长龙眼果实贮藏期并调节市场的目的。[方法]试验采用0、0.1、0.2、0.3、0.4、0.5、0.6 kGy共7个不同辐照剂量处理龙眼鲜果并将其置于3～4℃低温冷藏,研究辐照处理后低温冷藏对龙眼贮藏期和品质变化的影响。[结果]不同辐照剂量处理龙眼鲜果后,贮藏期可达41 d,并能有效地降低龙眼果实贮藏期间的失重率并提高好果率。其中,以0.4 kGy剂量辐照处理效果最好。与对照相比,失重率降低了49.10%,好果率提高了19.93%。[结论]0.4 kGy低剂量辐照处理结合低温贮藏可作为龙眼果实贮藏保鲜的一种推荐方法。     

功效系数法在汶川地震灾情综合评价中的应用

在MATLAB软件上利用功效系数法对汶川地震36个严重受灾县市依据灾情指标进行了综合分析。首先由变异系数和权重系数确定了影响灾情严重程度的主要灾情指标。然后依据总功效系数值对36个县市按照灾情严重程度进行了排序。最后依据总功效系数值的均值化数值对36个县市进行了分类。结果表明,评价结果更合理更符合实际情况。     

Effects of novel vaccines on weight loss in diet-induced-obese (DIO) mice

The purpose of the study was to test the therapeutic effects of novel vaccines for reducing weight gain and increasing weight loss in diet induced obesity (DIO) model. Male C57BL/6 J mice, fed a 60% Kcal fat diet for 8 weeks prior to the start of the study, were vaccinated via the intraperitoneal route with two formulations (JH17 & JH18) of chimeric-somatostatin vaccines at 1 and 22 days of the study. Control mice were injected with PBS. All mice continued to be feed the 60% Kcal fat diet for the 6 week study. Body weights were measured two times a week and food intake was measured weekly. At week 6, mice were euthanized and a terminal bleed was made and antibody levels to somatostatin and levels of insulin-like growth factor 1 (IGF-1) were determined. Vaccination with both vaccine formulations induced a statistically significant body weight change over the study period, as compared with PBS controls. Percentage of baseline body weight was also significantly affected by vaccination during the study period. Vaccinates finished the study at 104% and 107% of baseline weight, JH17 & JH18 respectively, while untreated controls reached 115% of baseline weight. Food intake per mouse was similar in all mouse groups during the entire study. Control mice did not demonstrate any antibody titers to somatostatin, while all vaccinated mice had measurable antibody responses (> 1:500,000 titer). IGF-1 levels were not statistically significant among the groups, but were elevated in the JH18 vaccinates (mean 440.4 ng/mL) when compared with PBS controls (mean 365.6 ng/mL). Vaccination with either JH17 or JH18 chimeric –somatostatin vaccines produced a statistically significant weight loss as compared with PBS controls (P < 0.0001), even though the DIO mice with continually fed a 60% Kcal fat diet. The weight loss/lower weight gain observations were even more significant, as all mice consumed similar amounts of food for the entire study. The presence of high levels of anti-somatostatin antibodies at 6 weeks was correlative with the weight observations and confirmed the success of vaccination.     

杂种荷斯坦成年母牛体重与体尺指标的相关回归分析

分析杂一代荷斯坦成年母牛体尺指标与体重的相关性,并进一步进行估测体重的回归分析,指导黄牛改良的生产实际及选育工作。以门源县麻莲乡2008年测量的495头杂种荷斯坦牛相关数据为基础,分析体重与体高、体长、胸围、管围的相关系数,构建估测杂种荷斯坦成年母牛体重的回归模型。结果表明：体重与体高、体长、胸围、管围的相关系数R分别为0．712、0．785,0．889,0．514;得到了估测体重的最优回归模型,Y=-648．399＋3．317X3＋2．062x2＋1．211x1（P〈0．01）（R2=0．877）。杂种荷斯坦成年母牛体重与体高、体长、胸围、管围存在明显的线性关系。     

小叶杨种子贮藏试验研究

杨树种子粒小、种皮薄、含水量高,在一般条件下贮藏两个月即丧失发芽能力,生产上均采用随采随播的方法。由于杨树结实有周期性,为了增加苗木当年生长量,提高苗木质量需进行春播,于是,杨树种子贮藏技术的研究不仅在生产上有着重要意义,而且对延长小粒种子寿命的探索亦具有一定价值。我们从1980年开始对杨树种子进行了不同采种期、不同贮藏方法等多项试验研究,其目的在于确定小叶杨种子的最佳采种期、最优贮藏条件,探索采种期及贮藏方法的不同对种子品质的影响,并欲从中了解它们的相关性。     

综合加权评分法的研究

在用综合加权评分法分析多指标试验结果时,由于各指标的变化趋势不同、数量级不同而造成加权评分值没有可比性,为解决这个问题,本文给出了一种有效的、规范化的解决方法。