钙素对夜间低温胁迫下番茄光合产物生产与积累的影响

以番茄品种辽园多丽为试材,利用人工气候室模拟设施生产中的夜间低温环境,研究钙素对6℃夜间低温下番茄叶片光合产物生产和积累抑制的缓解效应。结果表明,与正常温度生长的植株相比,6℃夜间低温显著降低了番茄叶片的光合作用及各器官的干物质积累和果实产量与品质;用钙素灌根处理均比低温生长对照植株提高了番茄叶片的光合作用、根系活力及果实产量和品质;但是用抑制剂EGTA和LaCl3灌根则进一步促进了夜间低温的抑制效应。说明钙素灌根处理能显著缓解夜间低温对番茄植株的光合物质生产和积累的抑制。     

星点试验设计优化甲维盐微囊悬浮剂制备工艺

以包封率为指标采用星点试验设计-效应面优化法对甲维盐微囊制备处方工艺进行优化.将微囊制备时的pH、温度、搅速作为考察因素,通过对微囊包封率测定结果进行二项式拟合绘制三维图像,从直观图中选取最佳试验设计点.二项式线性拟合Radj=0.927可用于对试验结果的预测,微囊制备pH为3.58,温度30.06℃,搅速选取700 r/min,包封率可达96.71％.结果表明:星点试验设计可对甲维盐微囊制备工艺进行优化,且优化效果良好.     

禽副粘病毒型鹅源分离株YG_(97)和鸡源分离株Y_(98)在体外培养细胞中的形态发生

用禽副粘病毒型鹅源分离株YG97和鸡源分离株Y98的鸡胚尿囊液毒感染原代CEF,制作超薄切片,运用透射电镜观察,结果显示,2株病毒引起CEF细胞器肿胀等轻微的超微结构改变,但不引起细胞的皱缩和裂解。结果表明鹅源YG97分离株和鸡源Y98分离株与NDV强毒株F48E8在致细胞病变特性上的差异。透射电镜观察结果还表明鹅源分离株YG97、鸡源分离株Y98在培养细胞上的形态发生与鸡新城疫病毒F48E8强毒株相似,是由细胞核复制的“纤丝样”结构出核孔在细胞浆内发育而成的。     

蒙古扁桃种子萌发的生理生化特性

研究了蒙古扁桃种子萌发过程中生理生化变化特性。实验结果表明，在干旱胁迫下蒙古扁桃种子活力明显下降，脂肪酶活性受抑制，脂肪降解成游离脂肪酸，游离脂肪酸转化为糖和糖的进一步代谢均受到不同程度的抑制，认为在干旱胁迫下种子活力下降是引起蒙古扁桃濒危的可能原因之一。     

硫在反刍动物营养中的作用及其需要量的研究

作者综述了硫在反刍动物营养中所起的重要作用,并对生产中硫的需要量进行了分析研究。     

禽类干扰素及其基因工程研究进展

干扰素是由干扰素诱生剂诱导生物细胞所产生的一类高活性多功能的糖蛋白。干扰素自被发现以来,由于其广谱抗病毒、抗肿瘤活性及其强大的免疫调节作用而受到研究者们的重视,在其基因结构、作用机理以及体外重组表达等方面都取得了巨大突破。作者综述了干扰素的基因结构、基因工程及重组干扰素的应用研究进展。     

利用扫描仪获取种子图像的研究

提出了利用扫描仪获取种子图像的研究方法。研究表明，用扫描仪获取的种子图像精度高、变形小、质量好，不易受外界环境和人为因素的影响，图像处理简单，能够较容易实现种子外部特征数据的自动采集，具有广泛的应用前景。     

Effect of Dietary Monensin on Production Performance and Nutrient Digestion of Lactating Dairy Cows

Twelve lactating Holstein dairy cows were selected via a replicated 4 × 4 latin square design to determine the effect of feeding different levels of monensin on the production performance and nutrient digestion of lactating dairy cows.The test was divided into 4 period and each period was 28 d (7 d for preliminary feeding and 21 d for formal feeding).The cows in control group were fed with the basal diet (TMR,group A),and the diets of the three experimental groups were added with different levels of monensin (300 mg/d,group B;400 mg/d,group C;500 mg/d,group D) on the basis of the TMR diet,respectively.The results showed that the diets containing monensin increased the milk yield and lactose percentage,and reduced milk fat percentage.Compared with control group,the milk yield of group C and D were significantly increased by 4.08% and 4.57% (P < 0.05) respectively,the lactose of group D was significantly increased by 1.99% (P < 0.05),and milk fat of group D was significantly reduced by 7.45% (P < 0.05).However,adding monensin had no effect on 4% fat corrected milk (FCM),solids-non-fat (SNF) and milk protein (P > 0.05).In addition,adding monensin also significantly increased body weight gain (BWG),digestibility of crude protein (CP),neutral detergent fiber (NDF) and acid detergent fiber (ADF) in diet.The BWG of group D was significantly increased by 34.62% (P < 0.05),and the digestibility of CP in three experimental groups were respectively increased by 3.73%,4.35%,5.35% (P < 0.01),and the digestibility of NDF and ADF in group D was respectively increased by 7.24% (P < 0.05)and 9.08% (P < 0.05) compared to the control group.Moreover,the dry matter intake (DMI) and the digestibility of ether extract (EE),calcium (Ca) and phosphorus (P) were not significantly changed by monension (P > 0.05).The results suggested that supplementing 400 to 500 mg/d monensin with diet per cow was optimal for production performance,nutrient digestion and economic benefit of lactating dairy cows.     

甲基托布津对醉马草种带内生真菌的灭菌活性

以中国西北天然草原的常见有毒植物——醉马草(Achnatherum inebrians)为研究材料,进行了内吸式杀菌剂——70%甲基托布津(thiophanate methyl)对醉马草种传内生真菌灭菌活性及种子萌发和幼苗生长影响的研究。结果表明,100倍甲基托布津可100%杀灭醉马草种传内生真菌,但该处理会显著降低(P0.05)醉马草幼苗的发芽指数,而对其它测量指标不造成显著影响(P0.05);其次为200倍药剂浸泡处理6 h,内生真菌杀灭率仅为61.2%,该处理种子发芽和幼苗生长与100倍药剂处理相比差异显著(P0.05)。因此,若不考虑对种子发芽指数造成的影响,甲基托布津稀释100倍、浸种2 h为剔除醉马草种传内生真菌的最佳方法。     

重组鸡α-干扰素对鸡新城疫感染的治疗及疫苗免疫的影响

对试验鸡进行新城疫人工感染的干扰素治疗试验,试验SPF鸡分成5组,1～3组分别于攻毒前24h、攻毒的同时和攻毒后24h注射重组鸡α-干扰素,4、5组作为病毒对照和空白对照。同时,还进行了重组鸡α-干扰素对新城疫弱毒苗和灭活苗免疫效果的影响试验,结果显示,试验2、3组的平均死亡时间明显延长,免疫试验免疫后14d注射重组鸡α-干扰素可以降低新城疫抗体的滴度。