Feeding value of an enzymatically digested protein for early-weaned pigs

Weanling pigs were used in a series of studies to determine the feeding value of an enzymatically digested protein product developed from a blend of swine and poultry abattoir by-products. The initial study used 156 pigs weaned at approximately 22 d of age to compare the product with menhaden fish meal in Phase II diets. The product supported equal growth rate, and there was no preference for diet exhibited based on inclusion level of the enzymatically digested protein product. The second study used 100 pigs weaned at approximately 21 d of age to compare the product with spray-dried animal blood cells in Phase II diets. The product supported a growth rate equal to that with the blood cells, and the combination of products enhanced growth rate (P<.05). The third study used 265 pigs to compare the product with spray-dried porcine plasma in a slope ratio growth assay. Results demonstrated a relative feeding value of 91% for the product over a 4-wk feeding period. The fourth study used 290 pigs to compare the product with spray-dried porcine plasma in Phase II diets; results demonstrated comparable growth performance. The final study used 180 pigs to compare the product with spray-dried porcine plasma in Phase I diets; results demonstrated comparable growth performance. These data indicate that the enzymatically digested abattoir by-product is a high-quality protein source for weanling pigs.     

禽流感卵黄抗体制备及其最佳沉降脱脂条件的确定

禽流感是由A型流感病毒引起的禽类的烈性传染病，常给养禽业带来灾难性的损失。一直认为控制禽流感的最好措施是全群扑杀，但是由于经济损失巨大，这一方法很难实施。目前，有些国家采用疫苗免疫预防禽流感，近年来在我国流行的低致病性禽流感H9血清亚型使用疫苗控制也取得了很好的效果。     

氟烷基因对猪生产经济性状的影响

猪应激综合征(Porcine Stress Syndrome,PSS)是受猪染色体上的隐性基因-氟烷基因控制,使得猪只在受到外界环境的刺激时,临床上出现发抖、呼吸急促、呼吸困难、皮肤变紫色、体温上升、肌肉硬化甚至死亡等一系列症状,外界压迫因素越大,对猪只造成的影响越强烈。文中综述氟烷基因对猪生长性能、繁殖性能以及猪肉品质的影响,以期为猪养殖者及实验室检测方面提供参考。     

Genetic diversity of Staphylococcus aureus isolated from ovine intramammary infections in Norway

Three hundred and eighty-four Staphylococcus aureus isolates obtained from mammary secretions from 332 ewes kept for meat production were typed by pulsed-field gel electrophoresis (PFGE). The ewes were from 242 flocks located in 13 counties distributed in four regions of Norway. In total, 64 different pulsotypes were identified, 31 of these were represented by a single isolate. Fifty-nine percent of the isolates belonged to one of five closely related pulsotypes. This group of pulsotypes occurred in all the counties. Although widely disseminated, the proportions of the prevalent and closely related pulsotypes differed between the regions. Nine pulsotypes were unique to single regions but the number of isolates belonging to each of these pulsotypes was low. Resistance to penicillin was found in only 3 of the 384 S. aureus isolates. These represented three different single banding patterns, not related to any of the prevalent pulsotypes found.     

Antibody-induced internalization of viral glycoproteins in pseudorabies virus-infected monocytes and role of the cytoskeleton: a confocal study

Addition of pseudorabies virus (PrV)-specific polyclonal immunoglobulins to PrV-infected monocytes induces internalization of plasma membrane anchored viral glycoproteins. This process may interfere with antibody-dependent cell lysis and resembles the well-studied physiological endocytosis process. A confocal study was designed to investigate whether the major cellular components, involved in physiological endocytosis (clathrin, actin, dynein and microtubules), play a role in this virological internalization process. In order to visualize the interaction of endosomes, which contain the internalized viral glycoproteins, with clathrin, actin, dynein and microtubules, a double labeling of viral glycoproteins and different cellular proteins was performed. Porcine monocytes were inoculated with the PrV-strain 89V87 at a multiplicity of infection of 50 for 13h. After the addition of FITC-labeled porcine polyclonal PrV-specific antibodies, cells were fixed with para-formaldehyde at different time points and afterwards permeabilized. The different cellular components were visualized with monoclonal antibodies and a Texas Red-conjugate, with the exception of actin, which was stained with phalloidin-Texas Red. The cells were analyzed by confocal microscopy. A clear co-localization was observed between the viral glycoproteins and clathrin and dynein during the internalization process. The microtubules were in close contact with the internalized vesicles. For actin no co-localization could be observed. It can be stated that clathrin, dynein and microtubules, important components during physiological endocytosis, are also of importance during the antibody-induced internalization of viral glycoproteins.     

Frequency of superantigen-producing Staphylococcus intermedius isolates from canine pyoderma and proliferation-inducing potential of superantigens in dogs

This preliminary study investigated the potential role of staphylococcal superantigens in the pathogenesis of canine pyoderma. The staphylococcal enterotoxins A (SEA), SEB, SEC and SED, and the toxic shock syndrome toxin-1 (TSST-1) were assayed in isolates from skins of dogs with pyoderma. Culture supernatants from 25 of 96 isolates were positive for multiple superantigens, with SEA and SEC being the most frequently detected. In in vitro stimulation of canine peripheral blood mononuclear cells and quantitative flow cytometry revealed that low concentrations of SEA and SEB were potent stimulators of blastogenesis of T cells.     

兰花病毒病研究进展

兰花具有极高的观赏和收藏价值,素有“绿色股票”之称。兰花病毒病可造成植株叶斑、坏死以及花朵变色、畸形等症状,严重影响其品质,是生产上的重要问题,这一情况,早已引起了世界各国的注意。１９９７年,我国动植物检疫机关将兰花病毒病列为有潜在危险性的有害生物,...     

修剪方式对广玉兰大树移植成活率及生长的影响

为提高大树移植成活率及探索修剪方式与大树移植成活生长的关系,以20a以上生广玉兰为试材,以全冠移植为对照(CK),分别采用剪去1/3枝叶量的轻度修剪(QX)、剪去2/3枝叶量的中度修剪(ZX)和不留枝叶的截干回缩修剪(JX)3种方式修剪后移植,经过3a连续试验观察,研究不同修剪方式对广玉兰大树移植成活率和生长的影响。结果表明,与CK相比,3种修剪方式极显著提高广玉兰移植后的成活率和新生叶片数、第2年(2013年)和第3年(2014年)的侧梢数、侧梢长度和底径以及第1年(2012年)和第3年(2014年)冠幅生长;与其他2种修剪方式相比,JX显著提高广玉兰移植成活率、第2年(2013年)和第3年(2014年)的侧梢数、顶梢长度、侧梢长度及冠幅生长以及第3年(2014年)的新生叶片数;显著提高第2年(2013年)和第3年(2014年)的侧梢底径。表明截干回缩修剪更有利于广玉兰大树移植的成活和复壮生长。