乳酸乳球菌乳脂亚种IMAU60064增殖培养基的优化

以分离自西藏那曲县罗玛镇传统发酵酸牦牛奶中的乳酸乳球菌乳脂亚种（Lactococcus lactis subsp．Cremoris）IMAU60064为试验菌株,研究其最佳的培养条件。对碳源、氮源、缓冲盐等培养基成分及培养条件进行优化,并采用响应面法对优选的碳源、氮源和缓冲盐类的组成含量进行优化,得到IMAU60064的增殖培养基为：葡萄糖23g／L、大豆蛋白胨11g／L、牛肉膏11g／L、胰蛋白胨5g／L、NaAC1．8g／L、K2HP041．2g／L、柠檬酸钠1．2g／L、MgSO4·7H200．4g／L、MnSO4·5H2O54mg／L、L-半胱氨酸盐酸盐0．5g/L、吐温80为1g／L。Lactococcus lactis subsp．cremorisIMAU60064在此增殖培养基中经30℃,14h培养活菌数可达到3．26×10^8cFu／mL,比在MRS中（6．54×10^7CFU／mL）提高近5倍。     

灌丛草地放牧山羊的牧草适口性与嗜食性及山羊采食率研究

通过对放牧山羊的牧草适口性，嗜食性和采食率及其相互关系的分析，表明山羊放牧对灌丛草地的植物适口性、嗜食性比率和采食率均以灌木嫩枝叶，中禾草和苔草属植物较优。季节性规律为：春季山羊喜哺食灌木嫩枝叶，灌木嗜食性比率较高，采食率也较高，夏季山羊喜草本植物，草本植物的嗜食性比率高于灌木，秋季山羊较喜啃食灌木枝叶，嗜食性比率灌木高于草本植物，采食率低于春季，灌木采食率高于草本植物。     

兰坪乌骨绵羊的引种适应性观察

兰坪乌骨绵羊是原产于云南省兰坪县、国内外唯一的具有乌骨乌肉特性的独特绵羊种质资源.为探明兰坪乌骨绵羊对环境的适应性,从云南省兰坪县引种兰坪乌骨绵羊160只至安徽省宁国市,通过观察和分析引种后原种和自繁羊群在新的生态条件和饲养管理条件下的成活和抗病、生理指标、生长发育和繁殖等性能.结果表明,虽然引入地与原产地距离遥远,生态差异大,羊群各方面表现良好,云南乌骨绵羊能够适应安徽省宁国市的自然生态环境和气候条件.     

Effects of bacterial direct-fed microbials and yeast on site and extent of digestion,blood chemistry,and subclinical ruminal acidosis in feedlot cattle

Two studies were conducted to determine whether a bacterial direct-fed microbial (DFM) alone or with yeast could minimize the risk of acidosis and improve feed utilization in feedlot cattle receiving high-concentrate diets. Eight ruminally cannulated steers, previously adapted to a high-concentrate diet, were used in crossover designs to study the effects of DFM on feed intake, ruminal pH, ruminal fermentation, blood characteristics, site and extent of digestion, and microbial protein synthesis. Steers were provided ad libitum access to a diet containing steam-rolled barley, barley silage, and a protein-mineral supplement (87, 8, and 5% on a DM basis, respectively). In Exp. 1, treatments were control vs. the lactic-acid producing bacterium Enterococcus faecium EF212 (EF; 6 x 10(9) cfu/d). In Exp. 2, treatments were control vs EF (6 x 10(9) cfu/d) and yeast (Saccharomyces cerevisiae; 6 x 10(9) cfu/d). Supplementing feedlot cattle diets with EF in Exp. 1 increased (P < 0.05) propionate and (P < 0.05) decreased butyrate concentrations, decreased the nadir of ruminal pH (P < 0.05), enhanced the flow of feed N (P < 0.10) to the duodenum but reduced that of microbial N (P < 0.10), reduced (P < 0.10) intestinal digestion of NDF, and increased (P < 0.10) fecal coliform numbers. Other than the increase in propionate concentrations that signify an increase in energy precursors for growth, the other metabolic changes were generally considered to be undesirable. In Exp. 2, providing EF together with yeast abolished most of these undesirable effects. Combining EF with yeast increased the DM digestion of corn grain incubated in sacco, but there were no effects on altering the site or extent of nutrient digestion. The diets used in this study were highly fermentable, and the incidence of subclinical ruminal acidosis, defined as steers with ruminal pH below 5.5 for prolonged periods of time, was high. Supplementing the diet with EF, with or without yeast, had limited effects on reducing ruminal acidosis. It seems that cattle adapted to high-grain diets are able to maintain relatively high feed intake and high fiber digestion despite low ruminal pH. The Enterococcus faecium bacterium and yeast used in this study were of limited value for feedlot cattle already adapted to high-grain diets.     

不同采毛方式对长毛兔血清蛋白及含氮代谢物水平的影响

文章分析了3种方式（剪毛、直接拔毛和药物拔毛）对皖系长毛兔采毛前、采毛后0、4、8、24、48 h血清蛋白及含氮代谢物变化规律的影响.结果发现：3种采毛方式均显著上调血清总蛋白和肌酐水平,而血清白蛋白仅受药物拔毛影响而显著上调;药物拔毛显著上调血清总胆红素和直接胆红素水平,同时直接胆红素还受其他两种采毛方式影响而显著下调;两种拔毛方式（直接拔毛和药物拔毛）显著上调血清尿素和尿酸水平,但剪毛对这两个指标没有影响.长毛兔在采毛后48 h内,多数血清指标可恢复到采毛前水平,或呈恢复趋势;该研究筛选获得采毛应激指标血清总蛋白和肌酐,拔毛应激指标尿素和尿酸,同时发现肌酐、白蛋白和胆红素受地塞米松的显著影响.该研究结果可为初步揭示不同采毛方式应激生化机制提供参考.     

铁苋菜提取物对仔猪生长性能、血液生化指标及肠道菌群的影响

目的:本试验旨在研究铁苋菜提取物对仔猪生长性能、血液生化指标及粪样菌群的影响.方法:选取同一批次的25日龄健康的外三元断乳仔猪120头,平均体重为9.60+0.65 kg/头,随机分为4组,每组3个重复,每个重复10头,公母各半;试验组分别为铁苋菜提取物组Ⅰ和组Ⅱ、抗生素组及对照组,铁苋菜提取物组Ⅰ和组Ⅱ在基础日粮中分...     

Canine renal failure syndrome in three dogs

Three dead dogs were brought to the College of Veterinary Medicine, Kyungpook National University for study. Clinically, all the dogs showed emaciation, anorexia, depression, hemorrhagic vomiting and diarrhea for 7~10 days before death. All the clinical signs were first noted for about one month after feeding the dogs with commercial diets. At necropsy, all 3 dogs had severe renal damage with the same green-yellowish colored nephroliths in the renal pelvis. They also showed systemic hemorrhage and calcification of several organs, which might have been induced by uremia. Microscopically, necrosis, calcification and calculi were detected in the renal tubules, and especially in the proximal convoluted tubules and collecting ducts of the kidney. These findings were supportive of a mycotoxic effect, and especially on their kidneys. However, the precise cause of the toxic effect in these cases of canine renal failure could not be determined.     

牛垂体细胞体外培养条件下催乳素分泌的调节—TRH、 GnRH、LH和PRL的影响

利用牛垂体细胞体外无血清培养技术,研究了促甲状腺素释放素(TRH)、促性腺激素释放素(GnRH)、促黄体激素(LH)和催乳素(PRL)对牛垂体细胞PRL分泌的调节。细胞在培养箱内预培养24小时后开始各项处理,以后隔24小时采集培养液一次,并换新的相同处理的培养液。结果表明:GnRH和TRH在第一次处理时均能显著增加PRL的分泌。加入1、10、100ng/ml的GnRH可使PRL分泌量分别增加53％(P<0.05)、111％(P<0.01)和60％(P<0.01),而TRH只有在10、100ng/ml的剂量时明显引起PRL释放增加(P<0.01)。第二次处理时细胞对TRH的反应消失,但对GnRH的反应却发生了逆转,PRL分别降低了70％(P<0.05)、68％(P<0.05)和73％(P<0.05)。表明GnRH和TRH在培养初期具有促进垂体细胞释放PRL的作用。LH(1、10、100ng/ml)对牛垂体细胞PRL的分泌无影响。但LH和TRH合用时,100ng/ml LH可明显地降低由TRH引起的PRL分泌(P<0.05)。PRL本身对牛垂体细胞的分泌有自我调节作用,100、1000ng/ml的PRL处理细胞使其分泌的PRL显著下降,分别降低70％(P<0.05)和100％(P<0.001)。此外1000ng/ml的PRL可显著地抑制由GnRH在第一次处理时引起的PRL释放。本实验在垂体细胞水平说明多种激素对PRL的分泌调节具有调控作用。     

以超滤技术浓缩猪细小病毒含毒细胞液的试验

在研制猪细小病毒灭活疫苗时,应用了超滤浓缩技术,提高了合毒细胞培养液中的抗原含量。为了保证浓缩的流量,减少对滤膜的污染,对含毒细胞培养液作了预处理一离心及微滤,以便除去细胞培养液中的细胞碎片、蛋白质等大分子物质及固形微粒。超滤时选用50000Da滤膜,在20psig压力下,经过5倍浓缩的PPV细胞培养液,血凝滴度提高2个滴度以上。病毒含量测定表明,TCID50／0．2mL由107左右升至109以上,以其配制疫苗,能显著地提高疫苗的免疫原性。超滤技术具有易于操作、高效、分离精度高、没有二次污染等优点,可以根据需要选择不同的浓缩浓度,对保证疫苗的质量具有重要作用。