饲用大豆肽的开发应用前景

大豆肽是以大豆为原料生产的产品 ,具有多种功能 ,近年来在食品工业中已得到广泛应用。将其应用于畜牧业生产中尚处于初期 ,但作为功能性饲料 ,大豆肽在畜牧业生产中具有广阔的开发与应用前景     

豆粕的新用途--鱼饲料

伦敦11月26日消息,英国科学家研究发现,他们可以改变鱼的食性,让肉食性鱼变成素食性。如果能成功并付诸实施,这项发现对豆粕和鱼粉市场都有深远的意义。这两个市场有紧密的联系,因为鱼粉和豆粕有相似的蛋白质含量及其它     

转基因草坪草的研究概况与展望

通过转基因技术在草坪草改良中应用的介绍,得出:采用现代基因工程来改良草坪草有巨大的商业潜力,草坪植物的组织培养和再生系统的建立为DNA的直接转移和农杆菌介导的转化提供了条件;遗传修饰的草坪草改善了其抗旱、抗高(低)温、抗病、抗除草剂和耐践踏的特性;携带异戊烯基转移酶基因的草坪草表现出分蘖力加强,严冬绿期延长;在期望利益的同时,应注意评估转基因草坪的生物安全性问题.     

血液替代品的发展前景

主要叙述了血红蛋白类及全氟碳化合物类血液替代品的种类、发展历史以及修饰的血红蛋白的安全性、有效性。随着生物技术的发展 ,各种改进的血液替代品层出不穷。在考虑血液替代品为人类服务的同时 ,对用于珍稀动物的血液代用品的研究也将是一个亮点     

鸡蛋品质的遗传多样性和选择前景

鸡蛋品质的专业选择将继续是蛋鸡育种策略中最重要的部分之一。遗传学和基因组学已确定了解决种蛋品质的新策略,包括使用高密度基因分型方法对只能在单一性别或生长（生产）后期进行的性状测定具有潜在益处的全基因组选择（Preisinger,2010;Albers,2010）。无论选择的方法是传统的还是现代的,如果能够更好地测定现有的性状,仍然正确的是测量方法的提高始终是必要的。同样的,如果评估品质的新方法具有明显的优势,就会被人们采纳。     

生态安全阈值研究述评与展望

随着全球变化的加剧,生态环境不断受到干扰和损害,生态安全问题日益突出。21世纪以来,生态系统风险或安全评估已成为全球变化和生态学研究的国际前沿和热点,其不同尺度不同类型生态安全阈值的判别和认知是生态系统风险或安全评估的关键和核心,更是全球变化胁迫下生态系统适应性管理的基础。本研究以生态系统不同胁迫要素为切入点,对生态安全阈值研究理论与实践发展进行了综述,大量文献显示通过提高生态安全阈值的判别和预估水平,不仅可揭示生态系统稳态转化与气候变化、碳氮循环、土地和草地利用、区域政策制度等胁迫因子的相互作用关系,而且对于退化生态系统修复及其生态环境保护与管理意义重大。当然,鉴于不同胁迫因子及其不同类型生态系统结构健康性及服务功能可持续性判别的复杂性,生态安全阈值厘定和预测能力极为有限,仍存在很大不确定性。     

植酸酶在饲料中的应用研究与展望

植酸酶(Phytase)作为饲料添加剂的一个品种,得到饲料工业和养殖业的普遍重视和广泛应用。畜禽饲料中的主要成分是植物性饲料,其中70％以上的磷元素以植酸盐的形式存在。一方面,由于单胃动物消化道内缺少植酸酶,以植酸形式存在的植酸磷很少能被利用;另一方面,饲     

Effects of long-term consumption of sewage solids on blood, milk and tissue elemental composition of breeding ewes

Fine-wool ewes received for 2 yr a complete pelleted basal diet (11% protein) or the basal diet fortified with 3.5% cottonseed meal (CSM; 12% protein) or gamma-irradiated (1 megarad) dried solids (SS; 12% protein) from primary (undigested) sewage (Las Cruces, New Mexico, municipal sewage). Five ewes fed each diet were sampled to determine Ag, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb and Zn in blood, milk and tissues. Tissues and blood were sampled at slaughter 40 d after weaning of lambs. Mean whole blood mineral concentrations were similar (P less than .05) among treatments 3 d postpartum; however, at 42 d after lambing (mean +/- SE) both basal- (54 +/- 2 micrograms/ml) and sewage-fed (54 +/- 2 micrograms/ml) ewes had elevated (P less than .05) blood Ca compared with ewes fed CSM (46 +/- 2 micrograms/ml). No biologically important differences were detected in the concentrations of elements in milk. Ewes fed SS had lower (P less than .05) blood Fe than animals in the other groups. Sewage-fed ewes also had higher (P less than .05) liver Fe (1,092 +/- 100 micrograms/g) than basal-fed ewes (626 +/- 100 micrograms/g); whereas Fe in CSM-fed ewes (873 +/- 100 micrograms/g) was similar to both. Basal-fed animals had 1.1- to 1.3 times more (P less than .05) liver Mg and two- to threefold higher liver Na than CSM or SS. Livers from SS-fed ewes had higher concentrations (P less than .05) of Cd (1.5- to 1.6-times) and Pb (1.4- to 1.9-times) than livers from CSM- or basal-fed ewes.(ABSTRACT TRUNCATED AT 250 WORDS)     

Anesthesia for fish

In fish, the most common purpose of anesthesia is to facilitate handling for physical examination and diagnostic sampling. Fish may also be transported to new locations more safely having been sedated. The author describes techniques of anesthesia in fish as well as the biologic characteristics of fish.     

Dietary replacement of fish meal by defatted and fermented soybean meals with taurine supplementation for pompano fish: effects on growth performance,nutrient digestibility,and biological parameters in a long-term feeding period

A 16-wk growth trial was conducted to examine the effects of dietary replacement of fish meal by defatted soybean meal (SBM) and fermented soybean meal (FSBM) with taurine supplementation on growth performance, nutrient apparent digestibility coefficient (ADC) and biological parameters of pompano fish. The FSBM was produced by fermenting SBM with Lactobacillus spp. Seven isonitrogenous and isoenergetic diets were formulated to replace 35% or 50% of fish meal by SBM or FSBM with taurine supplementation. The diets are denoted as follows: FM, SBM35, SBM35T, FSBM35T, SBM50, SBM50T, and FSBM50T. The FM (the basal diet) contained fish meal as a main source of dietary protein. Taurine was supplemented to SBM35T, FSBM35T, SBM50T, and FSBM50T at the level of 15 g/kg diet. Pompano juveniles with an initial body weight (BW) of 80 g reared in floating net cages were fed the experimental diets twice daily for 16 wk. Results showed that the final BW, weight gain, and feed conversion ratio of fish fed SBM35 and SBM50 were significantly lower than those of fish fed FM (P < 0.05), indicating that the replacement of fish meal by SBM at the rate of 35% in the diet is excessive for pompano. Supplementation of taurine to the SBM-included diets significantly increased growth performance and feed utilization (P < 0.05); however, these diets did not restore the performance back to a level equivalent to that of fish offered the basal diet. Meanwhile, fish fed FSBM35T had comparable growth and feed performances to those fed FM. Hematocrit values, total biliary bile acid levels, whole body lipid contents, and tissue taurine concentrations of fish fed SBM35 and SBM50 were the lowest among the treatments, but these parameters were improved by taurine supplementation and FSBM inclusion in the diet. Taurine supplementation increased lipid ADC, and SBM fermentation slightly enhanced both lipid and protein ADCs of the fish. These findings suggest that the combination of FSBM and taurine supplementation is an effective way to improve growth performance, nutrient digestibility, and biological parameters, and that FSBM with taurine supplementation can replace 35% of fish meal in pompano diets without any negative effects on growth and feed performances in a long-term feeding period.     

Effects of temperature and hypoxic stress on the oxygen consumption rates of the mudsucker fish Labeo capensis (Smith)

The specific oxygen consumption rate (VO ₂ IMb) of Labeo capensis, the freshwater mudsucker, was determined for small and large fish at winter (8°C) and summer (23°C) temperatures. VO JMb was also determined during hypoxic conditions of the experimental water. It was found that VO JMb does not differ substantially compared with other active fish. The VO 4Mb for a fish with a body mass of 250 g is 0,053 ml 0 ₂ per gram wet body mass per hour for fish acclimated at 8°C and 0,127 ml 0 ₂ per gram per hour for fish acclimated at 23°C. The calculated mass exponent, b, is 0,71 at 23°C and 0,68 at 8°C. Hypoxic conditions are relatively well tolerated especially by 23°C- adapted fish.     

Tropical fish medicine. Biopsy and rapid postmortem techniques for diagnosing diseases of fish

Biopsy and rapid postmortem techniques are simple to perform with commonly available instruments. Because the skin and gills are the target organs for so many infectious agents, biopsy is a very useful tool in pet fish medicine. The major requisite for successful diagnosis using biopsy materials is the ability to recognize different taxonomic groups of pathogens. Many of these pathogens may be present in clinically normal individuals, and their importance must be interpreted with other clinical findings. Rapid postmortem techniques can identify several common systemic diseases affecting pet fish. The usefulness of these procedures is highly dependent on the state of tissue preservation of the specimens presented.     

Current and future prospects for nanotechnology in animal production

Nanoparticles have been used as diagnostic and therapeutic agents in the human medical field for quite some time, though their application in veterinary medicine and animal production is still relatively new. Recently,production demands on the livestock industry have been centered around the use of antibiotics as growth promoters due to growing concern over microbial antibiotic resistance. With many countries reporting increased incidences of antibiotic-resistant bacteria, laws and regulations are being updated to end in-feed antibiotic use in the animal production industry. This sets the need for suitable alternatives to be established for inclusion in feed.Many reports have shown evidence that nanoparticles may be good candidates for animal growth promotion and antimicrobials. The current status and advancements of nanotechnological applications in animal production will be the focus of this review and the emerging roles of nanoparticles for nutrient delivery, biocidal agents, and tools in veterinary medicine and reproduction will be discussed. Additionally, influences on meat, egg, and milk quality will be reviewed.     

开县蚕业前景与机遇

回顾开县蚕业发展简史，从现状入手，分析蚕业发展前景。论述开县蚕业所面临的入世机遇、市场需求机遇、国家政策机遇、西部大开发“东桑西移”机遇、农业和农村经济结构调整机遇，指出21世纪开县蚕业前景十分光明，可持续发展的历史性机遇已经来临。