罗非鱼常见细菌性疾病及其防治措施

近些年,随着社会经济的快速发展,我国的养殖业发展规模越来越大,也获得许多人的青睐,其中罗非鱼在近几年的养殖规模迅速扩大,市场的需求量也显著增加,罗非鱼在市场中供不应求,因此也导致罗非鱼的价格暴涨。但因近些年水质环境发生很大变化,罗非鱼在养殖过程中出现了许多养殖病害,导致大量罗非鱼死亡,对鱼类养殖业者带来较大的经济损失。为了有效提高罗非鱼的养殖经济效益,下面针对罗非鱼养殖常见疾病的防治和治疗措施进行阐述。     

罗非鱼湖病毒感染研究进展

罗非鱼是全球第二大重要养殖鱼类,也是我国重要的养殖和出口产品。本文介绍了罗非鱼湖病毒的病原学、流行病学(地理分布、易感动物、传播方式、季节性、发病率和死亡率、组织病理特征)以及部分诊断技术进展,以期为我国有效防控该病提供借鉴。     

如何健康科学地饲养罗非鱼

要想真正实现健康养鱼,需要在许多养鱼环节上进行科学计算、严格执行,如罗非鱼目前在我国养殖比较广泛,是许多地方水产养殖的主要品种.     

罗非鱼的营养需求

随着水产养殖业的发展,罗非鱼已成为目前淡水养殖的主要品种之一。罗非鱼因其生长快、食性广、繁殖力强、病害少、肉质好,产量高等优点而广受欢迎。对罗非鱼营养需求基础的研究是有效提高养殖产量的前提。     

几种营养指标对奥尼鱼生长的影响

我国自1978年引进尼罗罗非鱼,1981年引进了奥利亚罗非鱼,利用奥利亚罗非鱼为父本和尼罗罗非鱼为母本进行杂交,获得了杂种优势明显的第一代─—称之为奥尼雄性罗非鱼,简称奥尼鱼。罗非鱼是尼罗罗非鱼、莫桑比克罗非鱼等罗非鱼族的总称,是热带性鱼类,原产于非洲。因其具有适应性强、食性广、病害少、繁殖易、生长快、产量高、肉质细嫩、味道鲜美等优点,已引起世界各国养殖工作者的重视,成为世界性主要养殖鱼类之一,在世界上其产量仅次于鲤鱼,居第二位。现将影响奥尼鱼生长的几种营养指标介绍如下：1．蛋白质蛋白质是生命生存的物质…     

罗非鱼营养生理研究进展

罗非鱼是我国重要淡水养殖鱼类。本文就近年来国内外学者关于罗非鱼的营养需求的研究结果进行综述．以期为罗非鱼营养研究及饲料配制提供科学参考。     

罗非鱼养殖效益不高的原因及应对技术

罗非鱼是近些年国内推出的名优水产品种,有着不错的养殖效益回报.为此,更多跟风养殖罗非鱼的人越来越多.但是,从反馈的养殖效益来看,普遍经济效益不高.文章以提升罗非鱼养殖效益为研究出发点,分析罗非鱼养殖效益不高的原因——水池不利罗非鱼养殖、鱼苗放养管理不善、投饵施肥不合理、防护安全管理不善等等.针对这些问题,笔者就提升罗非鱼养殖效益的技术措施,自挑选好养殖水池,做好消毒杀病虫害;掌控好放养时间,确保上市后有好行情;做好鱼苗选购工作,做好鱼苗放养管理;做好饵料投喂工作,注意池内水质配肥;优化池内养殖管理,调理水池水肥条件等方面做出概述,要点性知识以供参考和借鉴.     

吉富罗非鱼养殖技术

近年来，罗非鱼已成为世界性养殖鱼类之一。为进一步推广罗非鱼养殖，联合国ICLARM机构与菲律宾、挪威等国科研单位合作，通过从4个非洲原产地国（埃及、加纳、肯尼亚、塞内加尔）引进的尼罗罗非鱼品系与4个亚洲国家和地区（以色列、新加坡、泰国、中国台湾）养殖比较广泛的尼罗罗非鱼品系进行杂交并经综合逐代选育获得的优良品系——吉富罗非鱼。目前，该品系已选育到第13代，世界各国的养殖试验显示，吉富罗非鱼每向下选育一代，其生长速度加快6％～12％。该品种养殖的主要技术如下。     

罗非鱼蛋氨酸利用的研究进展

罗非鱼是我国南方最重要的水产养殖品种之一,而且近年来养殖规模迅速发展。但由于鱼粉价格昂贵而且鱼粉中含有较多的磷而不能被鱼类利用,因此,用植物蛋白质替代鱼粉成为最近动物营养与饲料研究的热点。蛋氨酸是罗非鱼饲料中所必需而植物蛋白质中含量不足的第一限制性氨基酸。所以,利用植物蛋白质源替代罗非鱼饲料中的动物蛋白质源,需要补充蛋氨酸以满足鱼类的生理需要。本文就罗非鱼对蛋氨酸等研究进展作一综述。     

罗非鱼的饲料营养与饲养

罗非鱼喜杂食,可饲喂各种各样的饲料原料。但由于罗非鱼的胃小而且发育不完全,故应不间断地投喂饲料,这一点与每次采食大量饲料而在8～12小时之内不再摄食饲料的鲑科鱼和鲇鱼有所不同。因此,整天多次投料,对罗非鱼会有好处。     

Comparisons of Angus, Charolais, Galloway, Hereford, Longhorn, Nellore, Piedmontese, Salers, and Shorthorn breeds for weight, weight adjusted for condition score, height, and condition score of cows

Breed differences for weight (CW), height (CH), and condition score (CS) were estimated from records (n = 12,188) of 2- to 6-yr-old cows (n = 744) from Cycle IV of the U.S. Meat Animal Research Center's Germplasm Evaluation (GPE) Program. Cows were produced from mating Angus and Hereford dams to Angus, Hereford, Charolais, Shorthorn, Galloway, Longhorn, Nellore, Piedmontese, and Salers sires. Samples of Angus and Hereford sires were 1) reference sires born from 1962 through 1970 and 2) 1980s sires born in 1980 through 1987. The mixed model included cow age, season of measurement and their interactions, year of birth, pregnancy-lactation code (PL), and breedgroup as fixed effects for CW and CS. Analyses of weight adjusted for condition score included CS as a linear covariate. The model for CH excluded PL. Random effects were additive genetic and permanent environmental effects associated with the cow. Differences among breed groups were significant (P < 0.05) for all traits and were maintained through maturity with few interchanges in ranking. The order of F1 cows for weight was as follows: Charolais (506 to 635 kg for different ages), Shorthorn and Salers, reciprocal Hereford-Angus (HA) with 1980s sires, Nellore, HA with reference sires, Galloway, Piedmontese, and Longhorn (412 to 525 kg for different ages). Order for height was as follows: Nellore (136 to 140 cm), Charolais, Shorthorn, Salers, HA with 1980s sires, Piedmontese, Longhorn, Galloway and HA with reference sires (126 to 128 cm). Hereford and Angus cows with reference sires were generally lighter than those with 1980s sires. In general, breed differences for height followed those for weight except that F1 Nellore cows were tallest, which may in part be due to Bos taurus-Bos indicus heterosis for size.     

Supplementation of broodmares with copper, zinc, iron, manganese, cobalt, iodine, and selenium

In experiment 1, 6 pregnant mares received a concentrate that contained a trace mineral premix that provided 14.3 mg Cu, 40 mg Zn, 28 mg Fe, 28 mg Mn, 0.08 mg Co, 0.16 mg I, and 0.16 mg Se/kg concentrate (group A). Seven mares received the same concentrate plus 502 mg Zn and 127 mg Cu once daily (group B). No differences (P > .05) in foal growth data, or Cu, Zn, and Fe concentrations of mare milk, mare serum, or foal serum were observed. In experiment 2, 6 pregnant mares received the same concentrate as group A (group C), and 8 mares received the same concentrate fortified with 4× the trace mineral premix (group D). Group C mares had higher serum Zn concentration at 1 day (P < 0.01) and 56 days (P < 0.04). Group C mares had higher milk Fe concentration at 28 days (P < .01), and group D mares had higher milk Cu concentration at 56 days (P < .01). Group C foals had higher serum Cu concentration at 14 days (P < .03). The results from this study provide no evidence to indicate that supplementing late gestating and lactating mares with higher dietary trace mineral levels than those recommended currently by NRC has any influence on foal growth and development, or on the Cu, Zn, and Fe concentrations of the mare milk, mare serum, or foal serum.     

Concentrations of strontium,barium, cadmium,copper, zinc,manganese, chromium,antimony, selenium,and lead in the liver and kidneys of dogs according to age,gender, and the occurrence of chronic kidney disease

This study was conducted to measure the concentrations of strontium (Sr), barium (Ba), cadmium (Cd), copper (Cu), zinc (Zn), manganese (Mn), chromium (Cr), antimony (Sb), selenium (Se), and lead (Pb) in canine liver, renal cortex, and renal medulla, and the association of these concentrations with age, gender, and occurrence of chronic kidney disease (CKD). Tissues from 50 dogs were analyzed using inductively coupled plasma mass spectrometry. Cu, Zn, and Mn levels were highest in the liver followed by the renal cortex and renal medulla. The highest Sr, Cd, and Se concentrations were measured in the renal cortex while lower levels were found in the renal medulla and liver. Female dogs had higher tissue concentrations of Sr (liver and renal medulla), Cd (liver), Zn (liver and renal cortex), Cr (liver, renal cortex, and renal medulla), and Pb (liver) than male animals. Except for Mn and Sb, age-dependent variations were observed for all element concentrations in the canine tissues. Hepatic Cd and Cr concentrations were higher in dogs with CKD. In conclusion, the present results provide new knowledge about the storage of specific elements in canine liver and kidneys, and can be considered important reference data for diagnostic methods and further investigations.     

电感耦合等离子-质谱法测定饲料中钠、镁、铬、锰、铁、铜、锌、砷、硒、镉和铅

应用电感耦合等离子-质谱技术(ICP-MS),建立饲料中钠、镁、铬、锰、铁、铜、锌、砷、硒、镉和铅等元素的测定方法。对饲料样品的前处理方法、仪器工作参数和11种元素标准曲线进行优化;并以加标回收、分析方法比对和重复测试说明方法的准确性和精密性。方法在0～1 000 ng/ml范围内线性良好,仪器检出限为0.557 7～5.072 ng/ml,具有良好的精密度,其回收率在88.1%～104.4%之间,相对标准偏差小于5.0%。同时与原子吸收和原子荧光方法进行比对,测定结果相近。所建立的方法简单、快速,可替代原子吸收和原子荧光方法测定饲料中的11种金属元素,为饲料的质量控制提供理想的元素分析方法。     

Granulocyte isolation from whole blood of goat, sheep, cattle, horse, dog, pig, and man

A simple two step procedure for the isolation of caprine, ovine, bovine, equine, canine, porcine and human peripheral blood granulocytes is described. After enrichment of granulocytes by centrifugation, contaminating erythrocytes are lysed hypotonically. Recovery, purity, and viability of the granulocyte suspensions are determined. FACScan analysis of the cell suspensions measuring cellular size by forward and sideward light scatter is compared with the corresponding analysis of whole blood leukocytes. Constituencies of the isolated cell suspensions and loss of granulocyte subpopulations through isolation procedure is discussed with regard to granulocyte function assays.     

Department of Clinical Veterinary Practices, School of Veterinary Medicine, University of Dublin, Trinity College, Ballsbridge, Dublin 4

Circular excised skin wounds in the thoracic and metatarsal regions of the dog were studied. A similar sequence of events took place in the two regions although differences did occur due to the different reactions of the tissues which surrounded the wounds. None of the wound cavities became filled with exudate during the early stages of healing. In the thoracic wounds the cavities were largely filled by the swelling and inward movement of adipose tissue. Epithelium first grew on the wound surface in the sector of the wound that was situated in the direction of hair flow. The average time to complete epithelization was similar in both sets of wounds. A zone of alopecia developed around the wounds.     

Effects of butorphanol, flunixin, levorphanol, morphine, and xylazine in ponies

The analgesic and behavioral effects of butorphanol (0.22 mg/kg), flunixin (2.2 mg/kg), levorphanol (0.033 mg/kg), morphine (0.66 mg/kg), and xylazine (2.2 mg/kg), given IM were observed in 8 ponies. These ponies were instrumented to measure response objectively to painful superficial and visceral stimuli. Effects on the cardiopulmonary system and rectal temperature also were evaluated in 6 of these ponies. Observations were conducted before drug injection (base-line values) and after injection at 30, 60, 120, 180, and 240 minutes. Xylazine provided the highest pain threshold for the first 60 minutes and a sedative effect for 105 minutes. The effects for superficial pain and visceral pain persisted 3 hours and 4 hours, respectively. Morphine produced good analgesia for superficial pain (30 minutes), whereas butorphanol provided good effect for visceral pain (4 hours). A slight degree of analgesia for visceral pain was obtained after morphine (1 hour) and levorphanol (4 hours); flunixin did not induce analgesia. Butorphanol, levorphanol, and morphine stimulated motor activity. Behavioral effects did not occur after flunixin was given. Xylazine decreased systolic, diastolic, and mean blood pressures. Marked increases in these pressures, heart rate, and respiratory rate were observed after morphine was given. Changes of central venous pressure, rectal temperature, and blood gas values remained within base-line limits after both drugs were given. Butorphanol increased heart rates for 1 hour; flunixin and levorphanol did not alter any of the above values.