2007年第一季度饲料和原料中霉菌毒素调查报告

1样品概述 2007年1－3月,百奥明公司共收集来自全国各地的样本68份,其中：玉米28份,配合饲料样本34份,DDGS、豆粕、棉粕、菜粕、花生粕及玉米蛋白粉各1份。[第一段]     

玉米副产物的饲用价值

本文主要介绍了玉米加工的副产物的种类、数量及常见几种主要玉米副产物的营养价值,并进一步阐述了其饲用畜禽的饲用价值。     

奶牛乳房炎发生的原因及诊断防治综述

乳房炎是奶牛最常见的疾病之一,它不仅严重影响患病牛的产乳量、乳的品质,延长产后发情时间和妊娠时问,而且危及人的健康。据国际奶牛联合会统计,20世纪70年代,奶牛临床型乳房炎患病率约20%,隐性乳房炎则高达50％;在美国饲养的1100万头奶牛中,半数患有各种类型乳房炎,日本全国平均乳房炎患病率为45．1％,法国奶牛整个第一泌乳期临床型乳房炎发生率为26．3％,在芬兰、挪威、瑞典,乳房健康问题分别造成35％、19%和22%的奶牛淘汰。     

热应激对动物体内蛋白质周转代谢的内分泌途径的影响

本文讨论了高温条件下机体内分泌激素对蛋白质合成、分解的影响,试图从内分泌角度解释高温对动物体蛋白质沉积的影响机理.     

家蚕母种继代蛾区选择方法对种性维持的影响

为了有效保持生产实用家蚕品种的优良性状,在家蚕母种继代繁育中采用5种选择方法选择继代蛾区,探讨种性维持效果。分析8年12代及F1代的成绩表明:所有性状以保持种性为主,采用选留平均数上下1个标准差范围内蛾区的稳定化选择和以茧丝质指标在平均数-0.5~1.0标准差范围内选择,并结合健康性指标选留高值的综合选择,有利于家蚕母种的种性维持。     

一例猪附红细胞体病的诊治

附红细胞体病是以溶血性贫血、黄疸、发热为主要特征的人畜共患的血液感染性疾病,其病原体为附红细胞体。本病例通过流行病学调查、临床症状观察、尸体剖检和实验室检验,确诊为猪附红细胞体病。在采取综合性防治措施后疫情得到了有效控制。     

家蚕乳糖酶-根皮苷水解酶基因BmLPH014192的表达和序列选择性剪接分析

乳糖酶-根皮苷水解酶(lactase-phlorizin hydrolase,LPH)是肠组织上皮细胞微绒膜上的一种糖蛋白,对乳糖和根皮苷有水解活性。鉴定了家蚕基因组中的一个LPH基因,命名为BmLPH014192。该基因CDS长1 305 bp,编码434个氨基酸,预测蛋白质分子质量为50.8 kD,等电点(pI)为5.35。将该基因的cDNA与家蚕基因组序列比对,显示其具有7个外显子,外显子/内含子边界处均符合GT-AG规则。将BmLPH014192与哺乳动物人、褐鼠、家兔和昆虫黑腹果蝇、冈比亚按蚊、二化螟、佛罗里达弓背蚁、大红斑蝶等的LPH进行氨基酸序列比对,相似度都在60%左右;聚类分析中BmLPH014192与昆虫类LPH聚在一起。芯片数据分析结果表明BmLPH014192在家蚕5龄第3天幼虫的9个组织中,只在中肠中有表达,并且表达量很高。在绿茧品种大造和白茧品种19-710幼虫的中肠中扩增到的特异性条带其长度分别为1 000 bp和750 bp,存在序列选择性剪接;在其它白茧品种的中肠中没有扩增出特异性条带。推测BmLPH014192的特殊表达方式可能与其在不同家蚕品种中肠组织中的特异性功能有关。     

Transient receptor proteins illuminated: Current views on TRPs and disease

The transient receptor potential proteins (TRPs) make up a very important family of ion channels responsible for a wide array of cellular functions. Originally identified in the visual system of Drosophila melanogaster, these channels are ubiquitously distributed throughout the mammalian system. The TRP family is divided into seven subfamilies in two groups: the first group comprises TRPC (canonical), TRPV (vanilloid), TRPM (melastatin), TRPN (Drosophila NOMPC) and TRPA (ankyrin). The second group contains TRPML (mucolipin) and TRPP (polycystin).The biophysical characterization of TRPs has revealed significantly different activation mechanisms and selectivity between channels. Functional studies have demonstrated that TRPs are necessary for a number of physiological processes, including sensation (such as taste, smell and temperature), hormone secretion and development. TRPs mediate these effects mainly by controlling the intracellular Ca²⁺ concentration, which acts as a second messenger. Recent research has linked TRPs to different diseases. This review considers the impact of TRPs on cell physiology and the abnormalities observed with channel dysfunction.     

Effects of breed, diet and sex on the alkaline phosphatase activity in walls of the bovine rumen and abomasum

Alkaline phosphatase (APase) activity in tissue samples, with adherent bacteria, was measured from two sites in the rumen and from two sites in the abomasum of 57 yearling Angus and Hereford bulls and heifers fed a high or a low energy diet. In the rumen, APase activity was higher at the caudoventral blind sac than at the dorsal sac in animals of both breeds fed the high energy diet and in Angus bulls fed the low energy diet, but the reverse was observed in Hereford bulls fed the low-energy diet (P less than .01). In the abomasum, APase levels were higher for bulls than heifers (P less than .01) and higher at the fundic than at the pyloric region (P less than .01). Morphological studies also showed that rumen samples from animals fed a high energy diet exhibited a more widely distributed APase activity and an increase in the digestive recycling of epithelial cells that produced some "pitting" of the tissue. The higher APase activity of the epithelial tissue of animals fed the high energy diet may be explained by the greater rate of cell death and renewal indicated by the higher mitotic index reported by other researchers who have studied the cell cycle of the rumen epithelium in ruminants fed high and low energy diets.     

Protein and lipid sources affect cholesterol concentrations of juvenile Pacific white shrimp, Litopenaeus vannamei (Boone)

Two experiments were conducted to evaluate the effects of protein and lipid sources on cholesterol, AA, and fatty acid content, and on biological performance of juvenile Pacific white shrimp, Litopenaeus vannamei (Boone). In Exp. 1, seven isonitrogenous and isocaloric diets were prepared using fish meal; soybean meal; casein; fish meal + soybean meal; fish meal + casein; soybean meal + casein; and fish meal + soybean meal + casein. In Exp. 2, seven isonitrogenous and isocaloric diets were prepared using fish oil; soy oil; poultry fat; fish oil + soy oil; fish oil + poultry fat; soy oil + poultry fat; and fish oil + soy oil + poultry fat. Nine shrimp (average BW 570 mg) were stocked per 60-L tank, with three tanks per diet in each experiment. Shrimp were fed to apparent satiation twice daily for 28 d. Protein sources affected shrimp cholesterol, feed consumption, feed efficiency, protein consumption, protein efficiency ratio, and crude body fat (P < or = 0.05), but not weight gain, survival, hepatosomatic index, body protein, ash, and AA composition. Body (without hepatopancreas) cholesterol concentrations were the highest in shrimp fed the diet containing fish meal (0.81%), lowest for those fed the casein diet (0.64%), and intermediate in the other dietary treatment groups (range 0.71 to 0.74%). Lipid source also affected shrimp body cholesterol, body fatty acid profiles, and fatty acid profiles in the hepatopancreas (P < or = 0.05), but not growth performance, body protein, fat, ash, and cholesterol concentrations in the hepatopancreas. Shrimp fed the fish oil diet had the highest body cholesterol (0.75%), whereas those fed the soy oil or poultry fat diets were lowest (0.66 and 0.65%, respectively). Results indicate that by replacing fish meal and fish oil with soybean meal and soy oil, shrimp growth performance is not affected, but body cholesterol concentration is reduced.