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61.
分别用虾蛄蛋白浆替代饲料中2%和4%的鱼粉,并以乌贼膏为对照,研究其对河蟹摄食和生长的影响。结果表明,饲料中添加虾蛄蛋白浆对河蟹的诱食作用与乌贼膏相当,但摄食量显著高于乌贼膏组。此外,虾蛄蛋白浆还具有明显的促进河蟹脱壳生长的作用,其作用机制可能与其中氨基酸、小肽、胆固醇等含量丰富有关。  相似文献   
62.
人工饲养条件下扬子鳄两种越冬方式的比较   总被引:1,自引:0,他引:1  
华北地区引进扬子鳄后 ,在室内安全越冬问题急需妥善解决 ,1996~ 1999年 ,采用人工控温使扬子鳄冬眠和不冬眠两种方式越冬。结果表明 ,在华北地区 ,在无法模拟自然条件使扬子鳄冬眠越冬的环境改变时 ,在人工控温下不冬眠是扬子鳄越冬的首选方式  相似文献   
63.
Wei  Jintao  Guo  Wanzheng  Yang  Xuehai  Chen  Fang  Fan  Qiwen  Wang  Hongwu  Zhang  Naifeng  Diao  Qiyu 《Tropical animal health and production》2019,51(7):1935-1941

This study was conducted to evaluate the use of ramie as forage on growth performance, serum biochemical indices, and meat quality of Boer goats. For this, 60 Boer lambs were divided into four groups fed the TMR with 0%, 10%, 20%, and 40% (control, and groups I, II, III, respectively) ramie. The experiment lasted for 90 days with a pretest for 15 days. Venous blood and longissimus dorsi (LD) muscle samples were collected after 24 h fasted at the end of the experiment. The results showed that ramie seems no significant changes in average daily gain (ADG) and other parameters for growth performance, only 40% ramie in TMR significantly reduced average daily feed intake (ADFI) (P < 0.05). Compared to the control, group II (20%) showed significant increases in total protein (TP) and globulin (GLB) levels, and decreases in albumin/globulin level (P < 0.05) in serum. Meanwhile, serum total cholesterol (TC) (P < 0.05) and free thyroxine (FT4) level were significantly reduced with up to 20% or more ramie in TMR. Moreover, the total amino acid and flavor amino acid levels in LD muscle were not affected by ramie. However, significant increases (P < 0.05) were observed in linoleic acid, polyunsaturated fatty acid, and polyunsaturated fatty acid/saturated fatty acid levels in group II. Overall, these results indicated that up to 20% ramie in TMR have no impairment in growth performance, health and meat quality, whereas high level ramie might have a negative effect on feed intake.

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64.
The objective of this study was to investigate the effect of storage temperatures and time on discoloration and oxidation of prepared chicken breast with paprika oleoresin. Freshly prepared chicken breast containing paprika oleoresin was stored at ?2, ?10, ?18°C, and an oscillating temperature between ?10 and ?18°C (?10/?18°C). A significant decrease in redness was detected at ?2, ?10, and ?10/?18°C. The lowest TBARS values and carbonyl contents were observed in the samples stored at ?18°C for 5 weeks. Also, the values of sulfhydryl groups gradually decreased with the increase in storage temperatures and duration. The results suggest a positive correlation between the loss of redness and oxidation in all samples. The findings indicated that the discoloration and oxidation of prepared chicken breast added with paprika oleoresin were inhibited significantly when stored at ?18°C.  相似文献   
65.
Background: There is growing interest in carbohydrate and protein nutrition to enhance the efficiency of animal production. Reduced-crude protein diets depress environmental pollution and feeding cost, but the challenge to their adoption is maintaining digestive function and growth performance of birds. The present study was conducted to evaluate the influence of different dietary starch sources and protein levels on intestinal functionality and mucosal amino acid catabolism.Methods: Six dietary treatments, based on maize and soybean meal, were offered to 360 AA+male chicks from 6 to 35 d post-hatch as a 3 × 2 factorial array. Either waxy rice or amylose was added to a conventional maize-soy diet to provide three sources of starch with different digestion rates and relatively high and low dietary protein levels. Growth performance, parameters of intestinal functionality and concentrations of free amino acid in the portal circulation were determined.Results: In the grower phase, starch source influenced(P 0.02) weight gain as diets containing amylose supported significantly higher weight gains than waxy rice. Significant increase of ileal ATP concentrations and Na+/K+-ATPase activity were found in amylose treatment. Also, amylose decreased BrdU positive cell numbers and down-regulated m RNA expression for CASP-3. GOT activity in the ileum was higher(P 0.01) in birds offered low protein diets and there was a trend(P = 0.057) for waxy rice as a starch source to increase ileal GOT activities. There was a significant influence on the concentration of seventeen amino acids in the portal circulation with tryptophan the one exception. Waxy rice as a starch source generated 13.6% and 22.4% numerically higher concentrations of non-essential amino acids than maize and amylose, respectively.Conclusions: Amino acid catabolism in the gut mucosa is subject to nutritional regulation. Given that amino acids can be spared from catabolism in the gut mucosa by supplementation of amylose, it follows their post-enteral availability would be improved and intestinal energy would be derived more efficiently from glucose.  相似文献   
66.
67.
郑果  王春明  洪流  王生荣 《草原与草坪》2011,31(6):65-68,74
针对大麦条纹病,选用7种杀菌剂对大麦品种甘啤4号种子处理后进行了室内毒力测定和室内发芽测定,同时进行了大田试验。结果表明,10%二硫氰基甲烷乳油,37/6敌萎丹悬浮种衣剂和0.5%二硫氰基甲烷种衣剂具有较好的抑菌效果,其EC。。有效抑菌浓度为2.563、7.345和19.721μg/mL;10%二硫氰基甲烷乳油、8%克...  相似文献   
68.
施用豆科绿肥对砖红壤有效磷含量的影响   总被引:3,自引:0,他引:3  
线琳  刘国道  郇恒福  高玲 《草业科学》2011,28(10):1781-1786
土壤缺磷是热带和亚热带地区作物生产的主要限制因子之一。本研究分析了14份热带、亚热带豆科绿肥施入土壤后对砖红壤有效磷含量影响的时间动态变化。结果表明,施用绿肥后不同时段能不同程度地提高土壤有效磷的含量,且施用绿肥后的土壤有效磷含量显著高于不施用绿肥土壤,其中木蓝(Magnolia lotungensis)对砖红壤有效磷含量增量变幅高达339%。此外,施用不同的绿肥对土壤有效磷含量的影响不同,但对土壤有效磷含量影响的基本规律一致。施用绿肥时砖红壤有效磷含量提高较大的最佳埋田时间为1个月。  相似文献   
69.
Liu, S., Guo, D., Guo, Y., Zhou, W. Preparation and pharmacokinetics of ceftiofur sodium liposomes in cows. J. vet. Pharmacol. Therap. 34 , 35–41. The objective of this study was to prepare ceftiofur sodium liposomes and assess their physical properties, stability, antibacterial effects, and pharmacokinetics. These liposomes appeared as a milky, light yellow suspension with encapsulation efficiency at 57.2 ± 1.17%, and there were no significant changes in all estimated indexes at 4 °C for 90 days. The minimum inhibitory concentrations of liposomes were all 1/4th that of ceftiofur sodium against Streptococcus suis, Staphylococcus aureus, Escherichia coli, and Salmonella enteritidis. Six healthy, adult cows in two treatment groups were dosed intravenously with ceftiofur sodium liposomes and ceftiofur sodium, serial blood samples collected, and plasma concentrations determined by high performance liquid chromatography. Intravenous plasma concentration profiles of liposomes best fit a two‐compartment model and the elimination half‐life was 2.11 times that of ceftiofur sodium. Thus, this liposome preparation provided therapeutically effective plasma concentrations for a longer duration than with the drug alone, making it more effective and convenient for use in treating bovine mastitis that requires long duration maintenance of therapeutic plasma concentrations.  相似文献   
70.
安徽金寨县引进三眠蚕诱导技术生产超细纤度生丝 ,并就开发生产超细纤度生丝提出建议意见  相似文献   
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