鹅营养需要量研究进展

近年来鹅营养研究取得了较大的进展。本文综述了鹅的能量、蛋白质、氨基酸、饲粮纤维、钙和磷需要量研究进展,并列举了国外的鹅饲养标准,以期促进在鹅生产中的应用,推动养鹅业发展。     

鸵鸟营养需要量的研究进展

鸵鸟是一种养殖经济价值极高的动物,产业化发展前景较好。本文就鸵鸟的消化特点及其对能量、蛋白质、氨基酸、矿物元素以及维生素等营养成分的需要量予以综述。     

山羊营养需要量的研究进展

世界上的山羊数量虽然很多,但有关山羊的营养需要量的研究迄今为止很少,至于山羊营养研究的文献资料就更少了。应用于山羊营养需要量的大部分数据来源于牛和绵羊的营养参数。本文着重就山羊的消化代谢特点、能量、蛋白质、维生素及矿物质营养需要量的研究进展及现状作了阐述。     

鸭微量元素营养需要量研究进展

微量元素营养在肉鸭生长发育和骨骼矿化及蛋鸭繁殖性能等方面发挥着重要作用。微量元素作为机体多种催化酶的辅助因子有利于提高鸭的抗氧能力和抗免疫力。随着鸭育种水平提高和饲养模式升级,鸭微量元素适宜需要量亟待重新评估和更新。文章阐述了鸭微量元素(铜、铁、锰、锌、硒)的营养生物学功能、需要量水平研究进展,推荐采用特异性生物学敏感指标评估微量元素需求量,确保满足最佳生长性能的同时有利于其骨骼发育和免疫性能提高。     

猪钙营养需要量研究进展

钙是猪体内重要的矿物元素之一,在维持机体正常生理机能中起到非常重要的作用。确定猪对钙的需要量,避免钙缺乏导致的一系列的疾病对动物具有很重要的意义。文章介绍了钙的营养代谢、猪钙需要量的研究方法、研究现状,以及影响钙需要量的因素等。     

鸡锰营养需要量研究进展

锰(Ｍｎ)广泛存在于生物界中,在动物组织中含量很少,但却是必需微量元素。Ｋｅｍｍｅｒｅｒ等(1931)首次发现,Ｍｎ为大鼠和小鼠维持正常生长和繁殖性能所必需。Ｗｉｌｇｕｓ等(1937)首次发现,Ｍｎ能有效地防止雏鸡发生滑腱症。在几种必需微量元素中,Ｍｎ对鸡等家禽具有特殊的营养重要性。本文重点对鸡Ｍｎ营养需要量的研究方法、研究现状和影响因素等作一概述。1　鸡Ｍｎ营养需要量的研究方法鸡Ｍｎ营养需要量的研究方法,从形式上看有多种,如饲养试验、平衡试验、屠宰试验等,而从本质上讲可分为两类:即剂量反应法与析因法。11　剂量反应法　…     

奶水牛营养需要量研究进展

奶水牛耐粗饲、耐湿热、抗疾病、适应性强,是最具开发潜力和开发价值的家畜之一。本文综述了奶水牛营养需要量的研究方法和营养需要量,以及能量水平与繁殖性能的关系的研究进展,为奶水牛的营养研究、制定饲养标准和科学饲养提供一定的参考依据。     

畜禽营养需要量测定方法的研究进展

近年来,国内关于营养需要量研究方法的报道有很多,适宜的畜禽营养需要量研究方法对制定合适的畜禽饲养标准十分重要。本文就目前国内对畜禽营养物质的需要量研究方法进行综述以及整合,为以后制定饲养标准提供合理的理论依据。     

肉用山羊营养需要量的研究进展

世界上的山羊数量虽然很多，但有关山羊的营养需要量的研究迄今为止很少，至于肉用山羊营养研究的文献资料就更少了。应用于山羊营养需要量的大部分数据来源于牛和绵羊的营养参数。本文着重就山羊的消化代谢特点、能量、蛋白质、维生素及矿物质营养需要量的研究进展及现状作了阐述。     

牙鲆营养需要的研究

<正>牙鲆(Paralichthys olivaceus)是鲽形目中的一种底栖肉食性鱼类,以其肉质细嫩、味道鲜美、营养丰富而深受人们的喜爱,市场需求旺盛,经济价值较高。但由于高效优质的人工配合饲料尚未真正开发出来,投喂鲜活饵料,造成水质污染,病害日趋严重,从而影响了牙鲆养殖业的规模发展和经济效益的提高。为了改变这一现状,本文对牙鲆的营养需要进行了研究,现将研究结果报道如下,为配制牙鲆配合饲料提供参考。     

水貂的营养需要和饲养管理

水貂为一种小型的毛皮动物，属于哺乳纲、食肉目、鼬科、鼬属。其皮毛珍贵，以细密、平齐、富有弹性、耐磨轻柔而素有裘皮之王的美称，是世界裘皮市场的主要产品。近年来，我国水貂养殖日益兴盛，根据养殖协会统计，截止到2006年底，我国水貂存栏量达到1000万只。但我国水貂养殖还存在着毛皮质量差、毛皮等级差等问题。营养水平和饲养管理是解决这些问题的关键因素。     

Pharmacokinetics of amoxicillin trihydrate in cultured olive flounder (Paralichthys olivaceus)

The study was aimed at investigating the pharmacokinetics of amoxicillin trihydrate (AMOX) in olive flounder (Paralichthys olivaceus) following oral, intramuscular, and intravenous administration, using high‐performance liquid chromatography following. The maximum plasma concentration (C_max), following oral administration of 40 and 80 mg/kg body weight (b.w.), AMOX was 1.14 (T_max, 1.7 h) and 0.76 μg/mL (T_max, 1.6 h), respectively. Intramuscular administration of 30 and 60 mg/kg of AMOX resulted in C_max values of 4 and 4.3 μg/mL, respectively, with the corresponding T_max values of 29 and 38 h. Intravenous administration of 6 mg/kg AMOX resulted in a C_max of 9 μg/mL 2 h after administration. Following oral administration of 40 and 80 mg/kg AMOX, area under the curve (AUC) values were 52.257 and 41.219 μg/mL·h, respectively. Intramuscular 30 and 60 mg/kg doses resulted in AUC values of 370.274 and 453.655 μg/mL·h, respectively, while the AUC following intravenous administration was 86.274 μg/mL·h. AMOX bioavailability was calculated to be 9% and 3.6% following oral administration of 40 and 80 mg/kg, respectively, and the corresponding values following intramuscular administration were 86% and 53%. In conclusion, this study demonstrated high bioavailability of AMOX following oral administration in olive flounder.     

Pharmacokinetics of difloxacin in olive flounder Paralichthys olivaceus at two water temperatures

In this study, the pharmacokinetics profiles of difloxacin in the olive flounder (Paralichthys olivaceus) were investigated following intravenous and oral administration (10 mg/kg BW) at 14 and 22 °C water temperatures. Plasma and tissue samples (muscle, liver, and kidney) were analyzed using an HPLC method. The results showed that the plasma concentration–time data for difloxacin were described commendably by two‐compartment open model at the two water temperatures. The absorption half‐life (t_1/2ka) of difloxacin after oral administration were 2.08 and 1.10 h at 14 and 22 °C, respectively; whereas the elimination half‐life (t_1/2β) was 4.41 and 2.38 h, respectively. The muscle concentration of 1.35 ± 0.19 μg/g was observed at 9 h at 14 °C, and 2.11 ± 0.33 μg/g at 6 h at 22 °C, respectively. For liver, the peak concentration of difloxacin 2.43 ± 0.30 μg/g occurred at 6 h at 14 °C, which was lower than the 3.34 ± 0.24 μg/g peak that occurred at 4 h at 22 °C. The calculated bioavailability of difloxacin was 68.07% at 22 °C, which was higher than the 53.43% calculated for 14 °C. After intravenous administration, the t_1/2β were 4.79 and 2.81 h at 14 and 22 °C, respectively. The results indicate that the peak concentrations in muscle and liver at 14 °C are approximately half of those achieved at 22 °C. However, the C_max in kidney at 14 and 22 °C were similar. The V_d values were 1.20 and 1.75 L/kg at 14 and 22 °C, respectively. These data indicated that both temperature and drug administration had significant effects on the elimination of difloxacin, and lower temperature or oral administration resulted in lower elimination.     

牙鲆致病性迟钝爱德华菌毒力基因的检测及序列分析

为探讨牙鲆致病性迟钝爱德华菌毒力基因携带与分布,以毒力基因为分子靶标研究其致病机理及建立快速检测方法,根据 GenBank 上的基因序列,设计2对引物扩增致病性迟钝爱德华菌毒力基因 fimA和小肠结肠炎耶尔森菌毒力基因 irp2,结果在7个供试牙鲆病例的130株致病性迟钝爱德华菌中,irp2毒力基因的阳性率为46．15％（60／130）,fimA 毒力基因的阳性率为100％,且均与已发表的参考菌株相应序列高度同源,同源性分别为97．32％和97．59％。可见耶尔森菌强毒力岛（HPI）在牙鲆致病性迟钝爱德华菌中广泛分布,但不同病例分离菌株间存在差异;fimA 毒力基因存在于所有的被检致病性迟钝爱德华菌中,可以作为快速检测致病性迟钝爱德华菌的标志物。     

The efficacy of amoxicillin sodium against streptococcosis in cultured olive flounder Paralichthys olivaceus and its pharmacokinetics

The efficacy of amoxicillin sodium for controlling field and experimental Streptococcus iniae and S. parauberis infections in olive flounder (Paralichthys olivaceus) was evaluated after a single intramuscular administration. Furthermore, the minimal inhibitory concentrations (MIC) against 21 Streptococcus strains were determined. In addition, the pharmacokinetics and residue depletion in olive flounder were investigated. Single intramuscular doses of amoxicillin sodium at 20, 40, 80, and 160 mg/kg b.w. fish significantly reduced cumulative mortality rates to 18.8–31.3% (P < 0.05) for S. iniae and to 5.0–15.0% (P < 0.01) for S. parauberis, whereas the S. iniae‐ and S. parauberis‐infected positive control groups showed cumulative mortality rates of 68.8% and 60.0%, respectively. In a S. parauberis outbreak, amoxicillin sodium reduced the cumulative mortality rate to 7.5% and 4.8% at 20 and 40 mg/kg b.w. fish, respectively, whereas that of the untreated control group was 35.2%. Peak plasma concentrations (C_max) following a single intramuscular dose of 40 and 80 mg/kg b.w. fish were 62.64 (T_max, 1.59 h) and 87.61 (T_max, 3.02 h) μg/mL, respectively, with large AUC_0?t/MIC and C_max/MIC ratios, and sufficient T > MIC (time for maintaining plasma drug concentration greater than MICs) for S. iniae and S. parauberis. The estimated withdrawal period of amoxicillin sodium from muscle of olive flounder was about 8 days at 40 mg/kg b.w. fish (at 22 ± 1 °C). These results demonstrated a single intramuscular administration of amoxicillin sodium to be effective against streptococcosis in olive flounder.     

罗氏沼虾营养需求研究进展

罗氏沼虾原产于印度洋、太平洋区域的热带和亚热带国家 ,因其具有食性广、生长快、个体大、生长周期短、肉质鲜美、营养丰富等特点而深受国内外消费者的喜爱 ,在我国水产养殖业中迅速发展 ,1 998年仅广东养殖面积就达 1 1 0 0 0多hm2 ,产量达到 3495 9t。虽然 1 999年以后南美白对虾的成功养殖对罗氏沼虾冲击很大 ,但 2 0 0 2年南美白对虾养殖过程中发生严重病害 ,市场价格一跌再跌使得罗氏沼虾的养殖又有所回升。1　蛋白质和氨基酸由于罗氏沼虾体内不能合成蛋白质 ,因此饲料中必须添加蛋白质。Balazs和Ross( 1 976)认为 ,以豆粕和鱼粉为主…     

A Viral Disease in Larvae and Juveniles of the Japanese Flounder Paralichthys olivaceus

Abstract

From 1985 to 1987, outbreaks of a disease resulting in mass mortality occurred in larvae and juveniles of the Japanese flounder Paralichthys olivaceus cultured at prefectural and private hatcheries in Hiroshima Prefecture, Japan. The disease occurred in 10-30-d-old fish that were reared at about 18–20°C, and mortality usually reached 80–90% in a few weeks. The affected fish had opaque fins and a hyperplastic epidermis on the fins and skin. Electron microscopy revealed hexagonal virus particles in the nucleus (100–140 nm in diameter without an envelope) and cytoplasm (190–230 nm with an envelope) of the affected epidermal cells. Although isolation of the causative agent by the use of five fish-cell cultures was not successful, the disease was transmitted to healthy larval flounder by exposing them to a 0.45-μm filtrate of diseased fish homogenate. The agent's morphological features and its sensitivity to ether, to a pH of 3, and to a 30min exposure to 50°C indicate it is a herpesvirus.