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991.
This experiment was conducted to study the effect of selenium and vitamin E supplement on semen quality, antioxidant enzyme activities and heat shock protein expression of goat in Hainan high temperature season.16 adult Hainan Black goat with good health and approximate weight were randomly divided into 4 groups, fed with basal diet(control group), basal diet+0.5 mg/kg Se(Se group), basal diet+100 mg/kg VE(VE group), and basal diet+0.5 mg/kg Se+100 mg/kg VE(Se+VE group), respectively.The experimental period was 93 d.Semen samples were collected in the last week of the experiment on two consecutive days.The semen quality, antioxidant enzyme activities and heat shock protein expression were analyzed.The results showed that compared with control group, the ejaculate volume was not significantly affected by Se or VE supplement(P>0.05).Sperm density and sperm motility were increased significantly by Se and VE supplement(P<0.05), and the abnormal rate was decreased extremely significantly(P<0.01).The goats fed with Se and VE also had higher activities of GSH-Px(P<0.01), SOD(P<0.05), CAT(P<0.05) and T-AOC(P<0.01), and lower MDA concentration in seminal plasma(P<0.05).The relative expression levels of HSP70 and HSP90 mRNA in supplement groups were decreased extremely significantly(P<0.01).However, there were some certain differences between the Se and VE supplement groups on semen quality and heat shock protein expression.In conclusion, the supplementation of Se and VE could help to improve goat semen quality by increasing the sperm density, sperm motility, the antioxidant enzyme activities, and decreasing the abnormal rate in hot season of Hainan.Finally, Se and VE supplement had good effects on relieving the environment heat stress.  相似文献   
992.
This experiment was designed to study the complex of Lactobacillus rhamnosus fermented herbal and Bacillus subtilis on White Feather broiler immunity performance and impact of Escherichia coli infection.360 one-day-old broiler chickens were randomly divided into 3 groups with 4 replicates in each group and 30 chickens per replicate.The pretrial period lasted for 7 d,and the experiment lasted for 35 d.The chickens in the group Ⅰ(positive control group) and group Ⅱ(negative control group)were all only fed a basal diet,group Ⅲ was test group,by additive 1% fermented herbal preparations,groups Ⅱ and Ⅲ were intraperitoneal injection of 1 mL E.coli at 35 d,broiler mortality,immune organ index,cecalmicroflora content,immunoglobulin levels,IL-2 and IL-6 content were tested.The results showed that injection of E.coli caused massive death of chickens,group Ⅱtook up to 75.00%,it was significantly higher than groups Ⅰ and Ⅲ (P < 0.05),the mortality in group Ⅲ was significantly lower than group Ⅱ(P < 0.05),was only 23.33%.Injection of E.coli maked spleen index and thymus index of group Ⅱincreased significantly (P < 0.05),the spleen index and thymus index of groups Ⅰ and Ⅲ were no significant difference (P > 0.05).E.coli counts was significantly decreased after injectionin group Ⅲ (P < 0.05),but the number of intestinal Lactobacilli of group Ⅲ was significantly increased (P < 0.05),and inhibited the propagation of E.coli,the counts of E.coli in groups Ⅰ and Ⅲ were no significant difference (P > 0.05).At 42 d,the sIgA of the intestinal fluid in group Ⅲ were higher than that of groups Ⅰ and Ⅱ with 11.99% and 36.56%,respectively(P < 0.05).The serum IgG concentrations of group Ⅲ was higher than that of groupsⅠand Ⅱwith 14.68% and 28.15%,respectively(P < 0.05).At 42 d,the IL-2 content of group Ⅱ was the lowest,it was significantly lower than group Ⅲ(P < 0.05),the IL-6 of group Ⅲ was significantly lower than group Ⅱ(P < 0.05).  相似文献   
993.
In order to understand the main bacterial pathogen species causing dairy cow mastitis in Liaoning, as well as the characteristics of drug sensitivity of the pathogenic E.coli,the milk samples from 75 dairy cows with clinical manifestations for mastitis in certain large-scale dairy farm in Liaoning were collected.The bacteria in milk were cultured and isolated with biochemical methods and in vitro drug sensitivity tests were processed with the isolated E.coli strains.The results showed that the main bacterial pathogen for dairy cow mastitis were E.coli(separation rate 58.7%),S.aureus(64.0%)and S.agalactiae(54.7%),and multiple infection including double and triple infection were identified.The drug sensitivity tests on the isolated E.coli indicated that the E.coli isolates were highly resistant to sulfonamides(resistance rate>85%)and chloramphenicol(resistance rate>30%),and they were relatively low resistant to ampicillin(9.5%),ciprofloxacin(9.5%),ceftiofur(7.1%)and ofloxacin(4.8%).The results was able to provide reliable theoretical basis for prevention and control of dairy cow mastitis in Liaoning area.  相似文献   
994.
Lactic acid bacteria (LAB) are suitable for rice straw silage fermentation, but have been studied rarely, and rice straw as raw material for ensiling is difficult because of its disadvantages, such as low nutrition for microbial activities and low abundances of natural populations of LAB. So we investigated the effect of application of LAB and chemical additives on the fermentation quality and microbial community of wilted rice straw silage. Treatment with chemical additives increased the concentrations of crude protein (CP), water soluble carbohydrate (WSC), acetic acid and lactic acid, reduced the concentrations of acid detergent fiber (ADF) and neutral detergent fiber (NDF), but did not effectively inhibit the growth of spoilage organisms. Inoculation with LABs did not improve the nutritional value of the silage because of poor growth of LABs in wilted rice straw. Inoculation with LAB and addition of chemical materials improved the quality of silage similar to the effects of addition of chemical materials alone. Growth of aerobic and facultatively anaerobic bacteria was inhibited by this mixed treatment and the LAB gradually dominated the microbial community. In summary, the fermentation quality of wilted rice straw silage had improved by addition of LAB and chemical materials.  相似文献   
995.
Nanotechnology applications in medicine have seen a tremendous growth in the past decade and are being employed to enhance the stability and bioavailability of lipophilic substances, such as florfenicol. This study aimed to examine the pharmacokinetic properties of the formulated oil‐in‐water florfenicol‐loaded nanoemulsion (FF‐NE). FF‐NE and florfenicol control (Nuflor®) were administered to the pigs at a dose of 20 mg/kg. Nanoemulsion formulation of florfenicol was highly influenced in vivo plasma profile. The in vivo absorption study in pigs indicated that Cmax (14.54 μg/mL) was significantly higher in FF‐NE, 3.42 times higher than the marketed formulation. In comparison with the control group, the relative bioavailability of formulated nanoemulsion was up to 134.5%. Assessment of bioequivalence using log‐transformed data showed that the 90% confidence intervals (90% CI) of Cmax and AUC0–∞ were 2.48–4.60 and 1.21–1.72, respectively.  相似文献   
996.
This study was undertaken to investigate the effects of ambient temperature, crude protein levels and their interaction on performance and serum biochemical parameters of broiler chickens. A total of 216 Arbor Acre broiler chickens (108 males and 108 females) were used in a 2 × 3 factorial arrangement and randomly reared at two temperatures (normal temperature: 23 °C; daily cyclic high temperature: 28–32 °C) and fed on three diets with different crude protein levels (153.3, 183.3 or 213.3 g/kg, with constant essential amino acids) from 28 to 42 days of age. Daily cyclic high ambient temperature decreased final body weight, average daily weight gain, average daily feed intake and serum total protein contents (p < 0.001, p < 0.001, p < 0.001, p = 0.008 respectively), but increased feed/gain, mortality, respiratory rate, rectal temperature, serum uric acid contents and serum creatine kinase activity (p = 0.008, p = 0.003, p < 0.0001, p < 0.0001, p < 0.0001, p = 0.003 respectively), irrespective of crude protein levels. At the ambient temperature, reducing crude protein levels resulted in an increase in feed/gain (p < 0.001), but a decrease in serum total protein and uric acid contents. Only serum creatine kinase activity in broiler chickens was interacted by daily cyclic high ambient temperature and dietary crude protein levels (p = 0.003). These results indicated that daily cyclic high ambient temperature had a great effect on performance and serum biochemical parameters in broiler chickens, whereas dietary crude protein levels affected them partially.  相似文献   
997.
以中间锦鸡儿和玉米、苏丹草、高丹草种子为试材,以蒸馏水为对照,采用培养皿滤纸法,研究了不同梯度(0.5、1.0、5.0、10.0、25.0mg·mL~(-1))中间锦鸡儿花水浸提液对3种受体作物种子萌发及幼苗生长的影响,以期对农林复合系统生产和构建提供理论依据和有益参考。结果表明:随着中间锦鸡儿花水浸提液质量浓度的增加,受体作物玉米、苏丹草、高丹草种子的平均发芽率和发芽指数均表现"低浓度促进,高浓度抑制"效应,但不同质量浓度水浸提液对3种农作物种子发芽的影响有差异性,在质量浓度为1.0mg·mL~(-1)时,3种农作物的种子相对发芽率间无显著差异(P0.05),除玉米外,另外2种受体作物种子的平均发芽率均表现为促进作用,且对高丹草的促进作用最大,RI=13.70%;在高浓度浸提液(C≥5.0mg·mL~(-1))处理下3种受体作物种子的发芽指数与对照均表现显著差异(P0.05)。玉米、苏丹草和高丹草的胚根、胚芽对中间锦鸡儿花水浸提液的化感效应均表现为"浓度效应";3种受体作物的苗高随着浸提液处理浓度的增大表现为"低促高抑",高浓度的浸提液对高丹草幼苗高度的抑制作用最强。花水浸提液对苏丹草和高丹草的幼苗干重化感效应表现为"低促高抑"效应,而对玉米幼苗干重表现为"高浓度抑制"效应。中间锦鸡儿花水浸提液对3种受体作物的化感作用综合效应大小依次为高丹草玉米苏丹草。  相似文献   
998.
以丹参为试材,采用土培盆栽法,于第1茬花开前进行高温胁迫处理,研究了高温胁迫对丹参生理指标、光合及叶绿素荧光特性的影响。结果表明:随着高温胁迫时间的延长,丹参叶片超氧化物歧化酶(SOD)活性呈上升趋势,而过氧化氢酶(CAT)活性呈下降趋势;丙二醛(MDA)、游离脯氨酸(Pro)含量均呈上升趋势,且与胁迫时间呈极显著多项式关系。净光合速率(Pn)、气孔导度(Gs)、胞间二氧化碳浓度(Ci)和蒸腾速率(Tr)均呈下降趋势,且各指标均与胁迫时间呈负相关。最大光化学量子产量(Fv/Fm)、PSⅡ潜在光化学活性(Fv/Fo)、有效光化学量子产量(Fv′/Fm′)、光化学淬灭系数(qP)和表观光合电子传递速率(ETR)均呈下降趋势,且各指标均与胁迫时间呈负相关,非光化学淬灭系数(NPQ)呈先上升后下降趋势。研究表明,高温(40℃)对丹参生理指标、光合及叶绿素荧光特性有较大的影响,且各功能指标共同作用,以减轻植株所受伤害。  相似文献   
999.
以2年生仁用杏为试材,采用盆栽方法,以正常供水(土壤含水量为田间最大持水量的75%)为对照,设置了轻度水分胁迫(55%)、中度水分胁迫(45%)和重度水分胁迫(30%)3个处理,开展了水分胁迫条件下仁用杏叶片光合色素、光合指标及叶绿素荧光参数等光合特性研究。结果表明:水分胁迫不同程度降低了类胡萝卜素含量、叶绿素a、b含量、净光合速率(Pn)、蒸腾速率(Tr)、水分利用效率(WUE)、最大荧光产量(Fm)、最大光化学效率(Fv/Fm)和PSⅡ潜在活性,且下降幅度随着胁迫时间延长而增大;轻度水分胁迫下降幅度很小,中度和重度水分胁迫下降幅度较大。  相似文献   
1000.
以新鲜小松菜为试材,采用小苏打复合液、乙酸锌复合液2种不同保绿途径对其冻藏前进行烫漂处理,并对小松菜钙、钠、锌元素含量进行测定,比较了2种不同前处理消解方法精确性,研究了不同处理方法对冻藏期小松菜相关品质指标的影响。结果表明:2种保绿途径均显著延缓了小松菜总叶绿素含量的损失(P0.05),不同程度增加了样品中钙、钠、锌离子含量,其中金属离子保绿途径的乙酸锌复合液处理样品的锌离子残留量超标,相比而言,碱保绿途径的小苏打复合液处理对冻藏期小松菜相关元素残留安全性及护绿效果较好,处理时应避免长时间、高温烫漂对产品硬脆度的破坏而抵消复合液中钙离子的保脆效应。  相似文献   
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