青霉素菌体蛋白营养价值评定及应用效果研究

分析结果表明：青霉素菌体蛋白含粗蛋白质４１．０％,钙１．４４％,总磷１．１１％,代谢能水平为９．９６ＫＪ／ｇ,５种主要的氨基酸含量如下：赖氨酸１．８４％,蛋氨酸０．６０％,胱氨酸０．６２％,苏氨酸１．７８％,色氨酸０．５０％;表观消化率分别为：８８．４％,９０．７％,６１．９％,８０．４％,９１．４％。通过饲养实验说明,在蛋鸡全价料中添加３％、５％、７％的青霉素菌体蛋白,可获得不低于玉米－豆粕日粮的生产成绩     

湖北省襄阳市一起犊牛隐孢子虫病的暴发调查

2021年12月23日,湖北省襄阳市某养殖场饲养的犊牛出现白痢、黄痢、血便等腹泻症状并死亡,病牛经抗菌消炎治疗,效果不明显。为查明发病原因和可能的发病风险因素,湖北省联合襄阳市和保康县动物疫病控制部门组建调查组,开展了紧急流行病学调查。调查组综合现场调查和实验室检测结果以及干预措施效果推断：此次疫病暴发由隐孢子虫感染引起;病原由外购牛羊引入的可能性最大,也不排除周边野生动物传入的可能;犊牛感染后因饲养管理水平低下导致抵抗力下降,因天气寒冷等产生应激,造成发病死亡。对发病犊牛进行消炎、隔离保温和补液等对症治疗,同时提升生产管理和生物安全水平,随后疫病得到有效控制。本次调查为中小规模养牛场防治隐孢子虫病提供了参考。     

意蜂采用2,3日龄工蜂幼虫产浆的研究

对意蜂采用２和３日龄工蜂幼虫产浆的王台接受率和不同时间取浆浆量进行了研究。研究结果显示：①２日龄工蜂幼虫的王台接受率（８２．４２％）与采用３日龄幼虫的（８１．２１％）无显著差异;②２和３日龄幼虫产浆的台平均产浆量最高峰分别在各自移虫后第６０小时和第４８小时,浆量较高时段分别在移虫后上时和第４２－５４小时;③２日龄幼虫产浆最高时段台平产浆量（０．３７５４ｇ）极显著高于３日龄的（０．３１５７ｇ）但采用     

鸭疫里默氏杆菌免疫原性研究Ⅱ.荚膜提取物免疫原性测定

本研究对Ⅰ型鸭疫里默氏杆菌的荚膜提取物的免疫原性进行了研究,结果表明,荚膜粗提物和经过苯酚抽提纯化后的荚膜提取物经２次免疫７日龄北京鸭后对同源细菌的攻毒保护率分别为９０％和７０％;采用ＥＬＩＳＡ检测荚膜提取物免疫后抗体产生规律显示,二者刺激机体产生的抗体水平有一定的差异,荚膜粗提物免疫组抗体水平高于纯化后的免疫组,前者抗体下降速度较后者慢。     

热变性法提纯蜂王浆中SOD的初步研究

测定了蜂王浆中超氧化物歧化酶（SOD）在60℃，65℃，70，75℃4个温度条件下热击后的酶活及蜂王浆在这4个温度条件下的蛋白质总含量，根据其比活（酶活／蛋白质含量）大小可知在70℃温度条件下热处理蜂王浆是提纯蜂王浆中SOD的最佳温度。     

奶牛热应激研究进展

当前以源自北欧的不耐热品种荷斯坦牛作为我国主要的奶用品种遍布全国各地,随着其生产性能的不断提高其热应激的表现也越来越严重。特别是在南方农区热应激造成的经济损失十分明显。因此,研究采取有效的预防措施,消除热应激对奶牛的影响,对保证奶牛高产稳产具有重要的经济意义。     

小肽饲料营养价值及评价方法

小肽一般是指二肽或三肽,小肽饲料就是通过化学或生物方法将本来不适合动物利用的蛋白原料分解,制成含有大量小肽的饲料产品。小肽饲料的营养价值在于小肽的吸收优势和其自身的质量。根据影响小肽营养价值的因素,可以选取小肽的总含量、平均肽链长度、特定小肽的含量、特定氨基酸的含量作为评价小肽饲料营养价值的指标。目前小肽含量的测定方法主要有双缩脲法、福林-酚法、三氯乙酸法、甲醛滴定法、凯氏定氮法、紫外光吸收法、消光系数法、考马斯亮兰法、层析比色法、高效凝胶色谱法、高效液相色谱法和CE-ESI-MS联用法。     

Chemical characteristics and relative bioavailability of supplemental organic zinc sources for poultry and ruminants

Eight commercially available organic Zn products and reagent-grade ZnSO4 x 7H2O (Zn Sulf) were evaluated by polarographic analysis, and solubility in .1 M K2HPO4-KH2PO4 buffer (pH 5), .2 M HCl-KCl buffer (pH 2), and deionized water. Fractions from these solubility tests were evaluated by gel filtration chromatography for structural integrity. Degree of chelation was generally positively related to chelation effectiveness determined by polarography. The organic sources were Zn methionine complex A (Zn MetA), Zn methionine complex B (Zn MetB), Zn polysaccharide complex (Zn Poly), Zn lysine complex (Zn Lys), Zn amino acid chelate (Zn AA), Zn proteinate A (Zn ProA), Zn proteinate B (Zn ProB), and Zn proteinate C (Zn ProC). Three experiments were conducted to estimate the relative bioavailability of Zn from the organic Zn supplements for chicks and lambs when added at high dietary levels to practical diets. Bone Zn concentration increased (P < .001) as dietary Zn increased in both experiments. When Zn Sulf was assigned a value of 100% as the standard, multiple linear regression slope ratios of bone Zn from chicks fed 3 wk regressed on dietary Zn intake gave estimated relative bioavailability values of 83 +/- 14.6 and 139 +/- 16.9 for Zn AA and Zn ProA, respectively, in Exp. 1 and 94 +/- 11.6, 99 +/- 8.8, and 108 +/- 11.4 for Zn Poly, Zn ProB, and Zn ProC, respectively, in Exp. 2. In Exp. 3, 42 lambs were fed diets containing Zn Sulf, Zn ProA, Zn AA, or Zn MetB for 21 d. Based on multiple linear regression slope ratios of liver, kidney, and pancreas Zn and liver metallothionein concentrations on added dietary Zn, bioavailability estimates relative to 100% for Zn Sulf were 130, 110, and 113 for Zn ProA, Zn AA, and Zn MetB, respectively. Except for Zn ProA, which was greater, the organic Zn supplements had bioavailability values similar to that of Zn Sulf for chicks and lambs. Bioavailability of organic Zn products was inversely related to solubility of Zn in pH 5 buffer in chicks (r2 = .91) and pH 2 buffer in lambs (r2 = .91), but not to an estimate of degree of chelation.     

苇状羊茅盐胁迫下生理效应的研究

应用砂培试验对苇状羊茅盐胁迫下的生理效应进行了研究,通过对苇状羊茅盐胁迫下的相对鲜重,相对干重,根冠比,脯氨酸含量,叶绿素含量及根系活力进行测定,表明,低浓度的盐处理下,苇状羊茅生长未表现出受不利因素影响,但此时羊茅已对外界高渗溶液做出生理反应,叶片中脯氨酸含量成倍增加;随着盐胭控浓度的增大,羊茅相对鲜重,相对干重,根系活力均降低２,生长和生理上都表现出盐害效应同时叶片中脯氨酸和叶绿素含量增加,反     

Identification and characterisation of microRNAs and Piwi-interacting RNAs in cockerels’ spermatozoa by Solexa sequencing

1. There has been substantial research focused on the roles of microRNAs (miRNAs) and Piwi-interacting RNAs (piRNAs) derived from mammalian spermatozoa; however, comparatively little is known about the role of spermatozoa-derived miRNAs and piRNAs within breeding cockerels’ spermatozoa.

2. A small RNA library of cockerels’ spermatozoa was constructed using Illumina high-throughput sequencing technology. Unique sequences with lengths of 18–26 nucleotides were mapped to miRBase 21.0 and unique sequences with lengths of 25–37 nucleotides were mapped to a piRNA database. A total of 1311 miRNAs and 2448 potential piRNAs were identified. Based on stem-loop qRT-PCR, 8 miRNAs were validated.

3. Potential target genes of the abundant miRNAs were predicted, and further Kyoto Encyclopedia of Genes and Genomes database (KEGG) and Gene Ontology (GO) analyses were performed, which revealed that some candidate miRNAs were involved in the spermatogenesis process, spermatozoa epigenetic programming and further embryonic development.

5. GO and KEGG analyses based on mapping genes of expressed piRNAs were performed, which revealed that spermatozoal piRNAs could play important regulatory roles in embryonic development of offspring.

6. The search for endogenous spermatozoa miRNAs and piRNAs will contribute to a preliminary database for functional and molecular mechanistic studies in embryonic development and spermatozoa epigenetic programming.