立枯青枯净防治水稻立枯病研究

采用播后覆土前按没剂量对床土喷施及大田分处理插秧测产的方法,对４３％立枯青枯净可湿性粉剂对水稻立枯病防治效果及水稻田间生长和产量的影响进行了试验。     

Bee pollen and propolis as dietary supplements for rabbit: Effect on reproductive performance of does and on immunological response of does and their offspring

To evaluate the effect of bee pollen (BP) and/or propolis (Pro) supplementation on rabbit does, 64 nulliparous NZW rabbits does were distributed among eight groups (eight animals/group). One unsupplemented group was the control; the other seven groups were supplemented, respectively, with zinc bacitracin (ZnB) at 100 mg, BP at 150 and 300 mg, Pro at 150 and 300 mg, BP+Pro at 150 and 300 mg of each three times/week, day after day continuously along eight parities. The BP300, Pro300 and BP+Pro150 groups had higher body weight of litter at birth and number of kids born alive. The BP supplementation at 150 mg increased plasma total protein and albumin than the control group. The BP or Pro at 150 mg decreased plasma T₃ than the other groups except for BP+Pro150. The ZnB group had significantly greater T₃/T₄ ratio compared to BP, Pro and BP+Pro at 150 mg. The BP+Pro150 group had less ALT than the control; BP300 and Pro 300 mg resulted in lower plasma AST than the groups Pro150 with or without BP and the control group. The plasma alkaline phosphatase of BP at 150 or 300 mg and BP+Pro150 was significantly greater than that of the Pro150 group. The BP+Pro300 group had higher WBCs than the other groups. In contrast, the lymphocytes were greater in the Pro and BP+Pro300 groups than in BP, Pro and BP+Pro at 150 mg. The groups supplemented with BP and BP+Pro at 150 and 300 mg had significantly greater SRBCs of doe rabbits and their offspring compared to the control and the ZnB group. The BP at 300 mg increased the serum albumin and α₁‐globulin than the control group. The Pro300 group had greater serum α₂‐globulin and β‐globulin than the control group. The total globulin was significantly greater for the 300 mg propolis‐supplemented groups than the control.     

猪乙型脑炎病毒SCYA201201株感染小鼠后突破血脑屏障能力研究

将猪乙型脑炎病毒SCYA201201株(F122代次,弱毒株)脑内接种小鼠,评估该病毒株对小鼠的致病性。通过腹腔接种小鼠,分别在接种后6、12、18、24 h观察小鼠脑部病理变化,同时利用荧光定量PCR方法检测其血液、脑组织E基因拷贝数,探究该毒株突破小鼠血脑屏障的能力,从而评估SCYA201201株(F122代次)作为弱毒活疫苗的潜力。结果显示,SCYA201201株(F122代次)高度弱化,对乳鼠的脑内半数致死量(LD₅₀)仅为4×10⁵ PFU·40 μL^-1。该毒株腹腔接种24 h内,小鼠脑部未出现病理变化,且荧光定量PCR检测为阴性,表明该毒株不能突破小鼠的血脑屏障,具有很高的安全性。     

滴度及注射方式对2型腺相关病毒载体表达效果的影响

由于腺相关病毒载体(adeno-associated viral vector,AAV)本身的侵染不具有神经元特异性,其在神经系统相关研究中会存在侵染范围不符合试验要求的情况,因此本试验拟研究不同滴度和注射方式对病毒侵染范围的影响.结果显示,在注射较高滴度的AAV2-CMV-EGFP(1.3×101 mg/L)3周后,...     

不同补饲方案对妊娠绒山羊冬春体况及胎儿发育的影响

结合放牧,给妊娠70天的绒山羊补饲精料和粗料,可使其在冬末早春处于增重状态。随着补饲水平的提高,母羊增重、羔羊初生重及初生羔羊皮肤的总体毛囊密度、次级毛囊密度和次级毛囊数与初级毛囊数的比值(S/P)均有不同程度的提高,但初级毛囊密度并不受影响。母体较胎儿对改善营养更敏感,胎儿快速增重与次级毛囊生长同期进行。羔羊出生时绝大多数初级毛囊已进入活动状态,而次级毛囊尚未开始活动。初生羔羊较成年山羊具有较低的S/P值和较高的总体毛囊密度。     

Short‐term methionine supplementation during the early post‐partum period in primiparous rabbits improves prolificacy associated with an increase in serum concentrations of IGF‐I

The aim of this study was to evaluate the effects of methionine supplementation on energy metabolism and reproductive performance during the early post‐partum period in primiparous does. Forty nulliparous New Zealand White does were used. Females were randomized in two groups at calving: the control group (n = 20) was fed with the basal diet, and the methionine group (n = 20) was fed the basal diet plus 1 g/animal/day of methionine from the day of calving to 4 days post‐partum. Results showed that methionine supplementation increased (p = 0.032) the concentration of insulin‐like growth factor‐1 with respect to control group 4 days post‐partum. It similarly increased the prolificacy (p = 0.03), the number of kits born alive per litter (p = 0.06) and the body gain weight of the litter during supplementation (p = 0.035). These results were observed despite the does in the methionine group having a deeper negative energy balance than the does in the control group. Finally, methionine supplementation did not affect receptivity (p = 0.23), fertility (p = 0.49), the number of kits born dead per litter (p = 0.86) insulin and metabolites as glucose, non‐esterified fatty acids and triglycerides. In conclusion, our results show that methionine supplementation during the first 4 days of the post‐partum period in rabbits increases total litter size and the corporal weight of kits and is associated with an increase in blood concentration of IGF‐1.     

饲粮中添加调味剂对断奶仔猪增重效果的影响

试验期Ⅰ组、Ⅱ组和对照组30d 采食量分别为27.1kg、17.4kg 和20.10kg;日增重分别为381g、192g 和240g;料重比分别为2.37、3.03和2.79.结果表明:调味剂对断奶仔猪有明显的诱食作用,而小茴香有抑制采食作用.为此正确选择调味品种,合理掌握用量,对断奶仔猪减少断奶应激损失,增加采食,提高日增重,降低饲料消耗有积极作用。     

温度与玉米绥玉21干物质积累及籽粒发育关系的研究

玉米绥玉21单株干物质和子粒干物质积累皆成极显著"S"型函数模型,温度对干物质影响的曲线与植株干物质积累曲线显著重合,利用温度曲线模型对植株干物质积累情况作出判断。     

Nutrient digestibility of rabbit does in different stages of reproductive cycle under tropical conditions

Effect of stages of reproductive cycle on body weight, feed intake and apparent nutrient digestibility of rabbits was investigated. Pregnant/lactating (PL) does increased their feed intake above pregnant lactating does. Dry matter (DM) digestibility was higher in pregnant does than in lactating, PL or open does. Digestibility of crude fibre, crude protein (CP) and nitrogen-free extractives (NFE) were significantly higher for open and pregnant does than lactating and PL does. Ether extract (EE) digestibility was similar for pregnant, lactating and PL does. Digestible CP requirement of does increased with physiological state from open to PL states. Open and pregnant does were meeting their protein requirement while lactating and PL does were not meeting their requirement. Feed intake was higher for first week pregnant, fourth week pregnant, first week lactating, first week pregnant/fourth week lactating and second week pregnant/fourth week lactating does than open does. DM digestibility was higher for first and fourth week pregnant does than the other physiological stages. EE digestibility was similar for all physiological stages. CP digestibility was higher in fourth week pregnant does than the other physiological stages. Fourth week pregnant does had higher NFE digestibility than first and fourth week lactating and the various stages of concurrent pregnant and lactating does. Open does, first and fourth week pregnant does were meeting their protein requirement while does in the first and fourth week of lactating and stages of concurrent PL were not meeting their requirement.