新疆细毛羊pEGFP-C2-KAP6.1真核表达质粒的构建与鉴定

试验采集新疆细毛羊皮肤组织,提取RNA,采用反转录聚合酶链式反应(RT-PCR)技术扩增出KAP6.1基因,并通过DNA重组技术将该基因片段重组于pEGFP-C2真核表达载体上,构建pEGFP-C2-KAP6.1重组质粒,并进行PCR、酶切鉴定。结果表明,本试验成功构建了新疆细毛羊的pEGFP-C2-KAP6.1真核表达重组质粒,为进一步研究该基因所编码的蛋白与毛品质的关系,以及培育超细羊毛等经济性生物学性状相互关系提供理论依据。     

鸡新城疫——减蛋综合征二联油佐剂疫苗的研制

应用鸡新城疫（ＮＤ）ＬａＳｏｔａ株和减蛋综合征（ＥＤＳ－７６）ＬＡ３株,分别接种鸡胚和鸭胚增殖病毒,血凝价分别达≥１：１２８０和≥１：１００００时,收取病毒,经福尔马林灭活,按一定比例加入吐温－８０、油佐剂制成ＮＤ－ＥＤＳ－７６二联疫苗,经无菌检验、安全性试验、剂量选择、保护性试验、免疫效果和免疫期测定及保存期观察,结果表明：该二联苗安全性好,于蛋鸡开产前１月皮下注射１ｍＬ／只,２５ｄ后ＮＤ和ＥＤＳ－７６抗体可先后达到高峰,免疫期１年。保存期４℃为１年,２０℃为３个月。     

Intramammary infusion of an Enterococcus faecium SF68 preparation promoted the involution of drying off Holstein cows partly related to neutrophil‐associated matrix metalloproteinase 9

A problem for dairy cows following milk stasis is to cope with a high risk of intramammary infection and there is a need to initiate an extensive renewal of secretory modules in mammary glands so that milk production in next lactation may be optimized. We recently reported that ultrasonicated Enterococcus faecium SF68 (SF68) is compatible with cow mammary glands and an enhancer of innate immunity during the immediate post‐milk stasis period. The current study further examines the concomitant effect of ultrasonicated SF68 on mammary tissue remodeling. Four Holstein cows each received intramammary infusions of regular antibiotic dry‐cow formula (positive control) and two different doses of SF68 in different quarters. Analyses of individual quarter secretion samples showed faster neutrophil infiltration, earlier modifications in protein composition, including caseins and lactoferrins, as well as more prompt elevation of the specific unit of 92‐kDa matrix metalloproteinase 9 (MMP9) in SF68‐infused quarters compared to the positive controls. Intramammary infusion of ultrasonicated SF68 seems able to accelerate the regression of mammary synthetic capacity and potentiate the breakdown of glandular extracellular matrix, indicating a more efficient mammary gland involution. Correlation analyses imply that the ability of ultrasonicated SF68 to induce faster neutrophil chemotaxis and the associated MMP9 release is partly responsible.     

美国国家兽医认证计划及其主要制度

为给我国新型兽医制度建设提供借鉴,对美国国家兽医认证计划(NVAP)及其主要制度进行了研究。研究表明,美国认证兽医是经美国动植物卫生监督局(APHIS)法定程序认证,代表联邦兽医(官)和州动物卫生官(SAHO)实施流通动物检疫监管,协助政府兽医(官)控制动物疫病的执业兽医,具有官方兽医属性。目前,全美80%的兽医为认证兽医,总量高达6.8万名,有效弥补了政府兽医(官)力量的不足。《美国联邦法规》第161.1条规定,NVAP的管理主要涉及认证兽医的分类、职责、培训教育、认证、复审、纪律处分等制度。     

四川白三叶根瘤菌遗传多样性及系统发育研究

为阐明四川部分地区野生白三叶根瘤菌的遗传多样性及系统发育地位,对分离自四川雅安、康定、泸定、西昌、成都和乐山6个地区白三叶根瘤的69株菌进行系统研究。采用16S rDNA限制性片段长度多态性分析(restriction fragment length polymorphism, RFLP)和16S rDNA基因、持家基因(recA、atpD、glnII)、结瘤基因(nodC)、固氮基因(nifH)系统发育分析的方法进行了研究。结果表明,16S rDNA PCR-RFLP中所有供试菌株产生了4种酶切图谱类型,表现出较为丰富的遗传多样性。持家基因与16S rDNA基因系统发育分析结果基本一致,9株代表菌株主要分布在α-变形菌纲(Alpha-Proteobacteria)的根瘤菌属(Rhizobium),并与豌豆根瘤菌三叶草生物型(R. leguminosarum bv. trifolii) ATCC 14480^T的亲缘关系较近。PCR可扩增出nodC和nifH基因片段,但从属于土壤杆菌属(Agrobacterium)的菌株LS1105中则扩增不出这两个基因。所有供试菌株被鉴定到了种的水平,证实了68株为白三叶根瘤菌,并通过不同采样地点菌株之间的比较,发现白三叶与根瘤菌的共生关系因地理分布不同而具有多样性,对于丰富白三叶根瘤菌资源及其开发利用具有重要意义。     

动物生理学实验教学单独设课之重要性

在高校的动物生理学教学中,实验教学是其中的一个重要组成部分。作为课堂教学的重要辅助和补充,动物生理实验教学效果对课堂教学具有极大的驱动作用。为突出动物生理实验教学的重要性,对动物生理学实验施行单独设课,这是考查理论教学效果、促进实验课教学质量的一种重要措施。     

昭通南方草山退化及人工改造对土壤种子库的影响

土壤种子库在退化生态系统的恢复中发挥着重要作用。本研究选取了昭通南方草山的4类草地,采集土样后通过萌发实验揭示其土壤种子库特征。结果表明：4类样地的土壤样品中共萌发出45种植物,隶属于20科39属,种子库储量为3 087～18 553粒·m^-2,种子库密度随土层加深均在逐渐降低。与轻度放牧草地相比,过度放牧草地的土壤种子库密度下降,但物种数量和多样性增加;严重退化的稀草裸斑土地种子库密度则显著降低(P<0.05),物种数量和多样性减少;而人工改造后的草地种子库密度显著增高(P<0.05)、物种数量和多样性也达到最高。昭通南方草山种子库与地上植被的总相似性系数为0.22～0.45,过度放牧草地、稀草裸斑土地和人工改造草地种子库与地上植被的相似系数均高于轻度放牧草地。总之,昭通南方草山退化和人工改造对土壤种子库产生巨大影响,上述结果可为后期退化草地治理提供理论依据。     

Heat stress-induced mucosal barrier dysfunction is potentially associated with gut microbiota dysbiosis in pigs

Heat stress(HS)can be detrimental to the gut health of swine.Many negative outcomes induced by HS are increasingly recognized as including modulation of intestinal microbiota.In turn,the intestinal microbiota is a unique ecosystem playing a critical role in mediating the host stress response.Therefore,we aimed to characterize gut microbiota of pigs’exposure to short-term HS,to explore a possible link between the intestinal microbiota and HS-related changes,including serum cytokines,oxidation status,and intestinal epithelial barrier function.Our findings showed that HS led to intestinal morphological and integrity changes(villus height,serum diamine oxidase[DAO],serum D-lactate and the relative expressions of tight junction proteins),reduction of serum cytokines(interleukin[IL]-8,IL-12,interferongamma[IFN-g]),and antioxidant activity(higher glutathione[GSH]and malondialdehyde[MDA]content,and lower superoxide dismutase[SOD]).Also,16S rRNA sequencing analysis revealed that although there was no difference in microbial a-diversity,some HS-associated composition differences were revealed in the ileum and cecum,which partly led to an imbalance in the production of short-chain fatty acids including propionate acid and valerate acid.Relevance networks revealed that HS-derived changes in bacterial genera and microbial metabolites,such as Chlamydia,Lactobacillus,Succinivibrio,Bifidobacterium,Lachnoclostridium,and propionic acid,were correlated with oxidative stress,intestinal barrier dysfunction,and inflammation in pigs.Collectively,our observations suggest that intestinal damage induced by HS is probably partly related to the gut microbiota dysbiosis,though the underlying mechanism remains to be fully elucidated.     

Foot use and hand preference during feeding in captive black‐and‐white snub‐nosed monkeys (Rhinopithecus bieti)

Postural origin theory predicts that body postures are related to hand preference in nonhuman primates due to hemispheric specialization. Foot preference, especially in manipulating objects, is also a good predictor of hemispheric specialization in humans. We studied limb (hand and foot) preferences in 11 captive adult black‐and‐white snub‐nosed monkeys (Rhinopithecus bieti) to see how limb preference is influenced by postures and foot manipulation. Hand preference was significantly different for this group between quadrupedal standing and clinging postures, and sitting and clinging postures, but not between bipedal standing and clinging postures. Individuals were significantly more likely to use the right hand in the clinging posture than in quadrupedal standing or sitting postures. In the sitting posture, individuals maintained their respective hand preference even when the food was on the other side of the body. There was a gender difference in the sitting posture, where females preferred their right hand but males preferred their left. Individuals who did not routinely use their feet to manipulate objects, compared to those who did, shifted to greater right hand use from the clinging posture to the bipedal posture. One male individual and his offspring were more likely to use their feet to manipulate objects than the rest of the monkeys. In the present study, we reveal the first evidence of a postural effect on hand preference in R. bieti as well as a foot preference in this species. Our results mostly agree with the postural origin theory and hemispheric specialization.     

不同缓控释氮肥对高羊茅草坪生长及氮素挥发的影响

 通过田间试验,研究了氮释放期为３０和６０ｄ的树脂包膜尿素（ＰＣＵ３０、ＰＣＵ６０）,硫包衣尿素（ＳＣＵ）,抑制剂型缓释尿素（ＵＩ）和普通尿素（Ｕ）对高羊茅草坪生长、氮素吸收及氮素挥发的影响。结果表明,在全年施氮量２６０ｋｇ／ｈｍ^２ 的情况下,ＰＣＵ３０、ＰＣＵ６０和ＳＣＵ 一年分春秋２次施用可以满足高羊茅草坪正常生长需要,其草屑累积量和氮素吸收量显著高于普通尿素一年４ 次施用处理;氮素气态损失方面,ＵＩ处理的氨挥发损失氮量高达４４．４２ｋｇ／ｈｍ^２,显著高于其他施氮处理,其Ｎ_２Ｏ 排放氮量为６．４６ｋｇ／ｈｍ^２,显著低于其他施氮处理;ＰＣＵ３０、ＰＣＵ６０、ＳＣＵ 处理的氨挥发量和Ｎ_２Ｏ 排放氮量分别为１７．６７,１３．５９,１８．５４ｋｇ／ｈｍ^２ 和８．１４,６．９２ ,９．９１ｋｇ／ｈｍ^２,显著低于Ｕ处 理。综合考虑各种因素,建议高羊茅草坪一年分春秋２次施用树脂包膜尿素ＰＣＵ６０较为适宜,可有效提高肥料利用率、降低氮素挥发损失,环境效益明显。