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61.
62.
The present study was undertaken to isolate the active compounds responsible for the anthelmintic activity of methanol extract of Semen pharbitidis against Dactylogyrus intermedius in goldfish (Carassius auratus). The active methanol extract was fractionated on silica gel column chromatography in a bioassay-guided fractionation, eventually yielding two bioactive compounds: palmitic acid and pharnilatin A by comparing spectral data (NMR and ESI-MS) with literature values. According to in vivo anthelmintic assays, they were found to be 50% effective at the concentrations (EC(50)) of 5.3 and 1.4 mg L(-1), respectively. The promising palmitic acid and pharnilatin A from S. pharbitidis were also subjected to acute toxicity tests for the evaluation of their safety to the host (goldfish). After 48h exposure, the mortalities of goldfish were recorded, and the established LC(50) values were 2.45- and 5.29-fold higher than the corresponding EC(50), demonstrating that pharnilatins A may have better application potential than palmitic acid. The present results provide evidence that pharnilatins A might be potential source of new anti-parasitic drug for the control of Dactylogyrus. 相似文献
63.
From 2007 to 2009, the prevalence of intestinal parasites was investigated in intensive and extensive pig farms in Chongqing, China. A total of 2971 samples from both sexes and five age categories (breeding boars, breeding sows, fatteners, growers and weaners) were evaluated by standard methods for the presence of helminth ova and protozoan oocysts, cysts and/or trophozoites. Of the 2971 pigs sampled, 362(12.18%) were infected with Ascaris suum, 301(10.13%) with Trichuris suis, 301(10.13%) with Oesophagostomum spp., 491(16.53%) with Eimeria spp., 149(5.02%) with Isopora suis, 677(22.79%) with Balantidium coli and 196(6.60%) with Cryptosporidium spp. Growers had the highest infection rate while breeding boars had the lowest among the five age categories. B. coli was the most common protozoan in all pig age groups. Pigs infected with multiple parasites were common. Risk factors such as management methods, seasons, ages, etc. can influence the infection rate to a certain degree. This investigation provides relevant data about risk factors for pig farmers, thus allowing them to make more appropriate antiparasitic treatments according to farm conditions and local climate in Chongqing. 相似文献
64.
采用四因素三水平正交试验,对藏羊血制备食用蛋白的工艺进行了分析。经分析食用蛋白粉水解最佳条件为:酶解用酶量4.5g,酶解温度为46℃,酶解时间为7.5h,酶解的pH值为10.5,活性炭作用于水解液时由室温升至80℃所需最佳时间为6~8min。 相似文献
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Jianjun Zang Jingshu Chen Ji Tian Aina Wang Hong Liu Shengdi Hu Xiangrong Che Yongxi Ma Junjun Wang Chunlin Wang Guanghua Du Xi Ma 《畜牧与生物技术杂志(英文版)》2014,5(1):39
The objective of this study was to evaluate the effects of supplemental magnesium (Mg) on the performance of gilts and parity 3 sows and their piglets. Fifty-six gilts (Trial 1) and 56 sows (Trial 2) were assigned to one of 4 treatments according to their mating weight, respectively. The treatments comprised corn-soybean meal based gestation and lactation diets (0.21% magnesium) supplemented with 0, 0.015, 0.03, or 0.045% Mg from mating until weaning. The results showed that magnesium supplementation significantly (P < 0.05) reduced the weaning to estrus interval in both gilts and sows. There were significant effects (P < 0.05) of supplemental magnesium on the total number of piglets born, born alive and weaned in sows. In late gestation and lactation, the digestibility of crude fiber (quadratic effects, P < 0.05), and crude protein (P < 0.05), were significantly influenced by magnesium in gilts and sows, respectively. There were differences among the 4 groups in terms of the apparent digestibility of dry matter and crude fiber in sows (P < 0.05) during both early and late gestation. The apparent digestibility of gross energy was increased for sows in late gestation (P < 0.05), and lactation (quadratic effects, P < 0.05). At farrowing and weaning, serum prolactin levels and alkaline phosphate activities linearly increased in sows as the Mg supplementation increased (P < 0.05). Serum Mg of sows at farrowing and serum urea nitrogen of sows at weaning was significantly influenced by Mg supplementation (P < 0.05). The Mg concentration in sow colostrum and the serum of their piglets were increased by supplemental magnesium (P < 0.05). In addition, growth hormone levels were linearly elevated (P < 0.05) in the serum of piglets suckling sows. Our data demonstrated that supplemental magnesium has the potential to improve the reproduction performance of sows, and the suitable supplemental dose ranged from 0.015% to 0.03%. 相似文献
67.
2005年10月以来,猪价掉头直下。截至2006年5月下旬,猪价已惨不忍睹,不少地区三元活猪价跌破6元/kg,土猪活猪价甚至跌破4元/kg。猪产业链上的诸多环节——养殖、饲料加工、原料,等等,均苦不堪言。 相似文献
68.
69.
本研究采用横断面研究方法,通过两个阶段的随机抽样检测,结合问卷调查,获得大连市羊群布鲁氏菌病血清流行率及感染风险因素,初步了解了当地养羊场户对布鲁氏菌病防控相关知识的掌握情况和行为实践特点。研究结果表明,大连市羊布鲁氏菌病场群血清流行率为8.89%(95%CI:6.14%~11.63%)。从饲养模式看,调查的6个种羊场均无布鲁氏菌病感染,而商品代饲养场和散养村羊群布鲁氏菌病血清流行率分别为13.33%(95%CI:5.64%~21.03%)和8.21%(95%CI:5.24%~11.17%),差异不显著(X~2=1.93,p=0.170.05)。从饲养品种看,不同品种羊群之间的布鲁氏菌病血清流行率差异也不显著(X~2=0.15,p=0.930.05)。单因素分析结果表明,"与其他养羊场户共用种公羊""产后胎衣丢弃和喂狗""流产物喂狗""与其他养羊场户共用交通工具""近一年羊贩子进羊圈""近一年在交易市场买卖羊"等行为是羊群感染布鲁氏菌病的风险因素,而"购入前检测布鲁氏疾病"是显著的保护性因素。进一步的logistic回归分析表明,"近一年在交易市场买卖羊"(OR=4.91,95%CI:1.57%~15.35%)"流产物处理不当"(OR=1.87,95%CI:1.06%~3.30%)是主要的羊群布鲁氏菌病感染风险因素。"知信行"调查结果表明,大连市养羊从业者对布鲁氏菌病的认知程度较好,说明兽医部门的宣传工作有成效。但从行为实践角度来看,仍有部分养羊场户存有侥幸心理,在日常养殖和生活中不采取降低布鲁氏菌病感染风险的措施。 相似文献
70.