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61.
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用分别添加0.5%、1%与10%满江红的配合饲料喂1日龄AA肉鸡,21日龄、42日龄的体重0.5%、1%添加组显著高于10%添加组和对照组(P〈0.05)。0.5%、1%添加组鸡只粪便的双歧杆菌和乳酸茵的总数较对照组增多60%,而大肠杆菌数量则下降67%。不同浓度的满江红溶液,添加于培养基中,进行体外增茵和抑茵试验,满江红对双歧杆菌体外增殖和大肠杆菌体外抑制均有良好的效果。以上结果表明,满江红可以作为家禽益生元。 相似文献
63.
抗鸡球虫药的筛选分为体内筛选和体外筛选。体外筛选具有简易、迅速、准确和经济的优点。本文在前人大量工作的基础上,总结了体外筛选的全过程,并分述了细胞培养筛选法和鸡胚培养筛选法。 相似文献
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北京油鸡胚胎成纤维细胞系建立与生物学特性研究 总被引:12,自引:3,他引:12
采取组织块直接培养法,对北京油鸡胚胎组织进行原代和继代培养,成功地建立了成纤维细胞系。并对培养细胞进行了形态学、细胞生长动力学观察,以及核型和乳酸脱氢酶、苹果酸脱氢酶的同工酶分析。结果表明,该细胞系的群体倍增时间(PDT)为24h;细胞染色体中二倍体占主体,为76%~88%;乳酸脱氢酶、苹果酸脱氢酶同工酶电泳图谱与本室其它细胞系有明显差别;细菌、真菌、病毒、支原体检测呈阴性。该细胞系的建立,使北京油鸡这一国家重要种质资源在细胞水平上保存下来,也为基因组文库和体细胞克隆等研究提供了理想的生物材料。 相似文献
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研究旨在明确常山口服液治疗鸡球虫病的疗效和最佳给药剂量。试验选取90只14日龄健康雏鸡,随机分为9组,每组10只,即常山口服液组(分别为2.5、5.0、15.0、25.0、35.0、50.0 m L/L水剂量)、妥曲珠利组(1 m L/L水)、感染对照组和健康对照组。除健康对照组外,每只鸡接种7×104个柔嫩艾美耳球虫广东分离株的孢子化卵囊,饮水给药7 d,观察其疗效。结果显示,常山口服液各剂量组其盲肠和十二指肠的肿胀现象较感染对照组明显减轻,血液性内容物明显减少,抗球虫指数(ACI)分别为87.7、136.2、141.8、136.2、109.7和108.0,均高于感染对照组;常山口服液按5.0、15.0及25.0 m L/L水剂量给药,抗球虫指数均高于对照药物妥曲珠利组(ACI=124.8)。结果表明,人工感染条件下,常山口服液较化学药物妥曲珠利具有更好的抗球虫疗效,且作为中药提取物,疗效对比试验效果较为理想。 相似文献
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Effect of a 1800 MHz electromagnetic field emitted during embryogenesis on chick development and hatchability 下载免费PDF全文
K. Pawlak Z. Nieckarz A. Sechman D. Wojtysiak B. Bojarski B. Tombarkiewicz 《Anatomia, histologia, embryologia》2018,47(3):222-230
The level of artificial electromagnetic field (EMF) has steadily increased with the development of human civilization. The developing chicken embryo has been considered a good model to study the effects of EMF on living organisms. The aim of the study was to determine the effect of a 1800 MHz electromagnetic field during embryogenesis on the frequency of chick embryo malformations, morphometric parameters of the heart and liver and concentration of corticosterone in blood plasma, lipid and glycogen content in the liver of newly hatched chicks. A 1800 MHz EMF was found to shorten the duration of embryogenesis (earlier pipping and hatching of chicks) while having no effect on the quantity and quality of chicks and on increasing the incidence of embryo malformations. Exposure of chick embryos to EMF caused decreases in relative heart weight and right ventricle wall thickness. The pipping and hatching of chicks can be accelerated by stressful impact of EMF, which is confirmed by a significant increase in plasma corticosterone concentrations and decrease in fat and glycogen in the liver of chicks exposed during embryogenesis on the electromagnetic field with a frequency of 1800 MHz. 相似文献
70.
Meta‐analysis of the energy and protein requirements of hair sheep raised in the tropical region of Brazil 下载免费PDF全文
A. P. Oliveira E. S. Pereira S. Biffani A. N. Medeiros A. M. A. Silva R. L. Oliveira M. I. Marcondes 《Journal of animal physiology and animal nutrition》2018,102(1):e52-e60
The objective of this study was to estimate, through mathematical models, energy and protein requirements for maintenance and gain of hair sheep raised in the tropical region of Brazil. To determine the equation parameters, a meta‐analysis of seven independent experiments of nutrient requirements was performed, comprising a total of 243 experimental units (animals), which were conducted under tropical conditions, using hair sheep in growing and finishing phases and endowed of the following quantitative data for each animal: body weight (BW ), empty body weight (EBW ), average daily gain (ADG ), empty body gain (EBG ), heat production (HP ), metabolizable energy intake (MEI ), retained energy (RE ), metabolizable protein intake (MPI ) and body protein content. The regression equations generated were as follows: for Net Energy for maintenance, (NE m): ; for Net Energy for gain, (NE g): ; for Metabolizable Protein for maintenance,(MP m): MPI (g/day) = 24.8470 (±7.3646) + 560.28 (±99.6582) × EBG (kg/day); for Net Protein for gain, (NP g): . The NE m requirement was 0.246 MJ EBW?0.75 day?1. The metabolizable energy for maintenance requirement was 0.391 MJ EBW?0.75 day?1. Considering an ADG of 100 g, the NE g requirement ranged from 0.496 to 1.701 MJ/day for animals with BW ranging from 10 to 40 kg respectively. The efficiencies of use of the metabolizable energy for maintenance and gain were 0.63 and 0.36 respectively. The MP m requirement was 3.097 g EBW?0.75 day?1. Considering an ADG of 100 g, the NP g requirement ranged from 12.4 to 10.5 g/day for animals with BW ranging from 10 to 40 kg respectively. The total metabolizable energy and protein requirements were lower than those reported by the NRC and AFRC systems. Thus, our results support the hypothesis that nutrient requirements of hair sheep raised in tropical regions differ from wool sheep raised in temperate regions. Therefore, the use of the equations designed in this study is recommended. 相似文献