The Pulmonary Clearance of Bacteria by Calves and Mice

Using a modified aerosol generator, white mice and calves were exposed to aerosols of viable Staphylococcus aureus and Pasteurella haemolytica and the clearance of the inhaled organisms by the lungs of the experimental animals was measured. Fifty-seven percent of inhaled S. aureus were cleared in two hours by the mouse lungs, 79% were cleared in four hours and 93% were cleared in eight hours. Fifty-six percent of inhaled P. haemolytica were cleared in two hours by the mouse lungs, 76% were cleared in four hours and 93% were cleared in eight hours. Seventy percent of inhaled S. aureus were cleared in two hours by the calf lungs, 90% were cleared in four hours and 95% were cleared in eight hours. Seventy-five percent of inhaled P.haemolytica were cleared in two hours by the calf lungs, 90% were cleared in four hours and 92% were cleared in eight hours.     

己烯雌酚多克隆抗体的制备和鉴定

用混合酸酐法合成的BSA-DES免疫兔子,制备抗DES的特异性抗体,分别用混合酸酐法和碳二亚胺法合成的OVA-DES作为包被原检测抗体;用混合酸酐法合成的OVA-DES和碳二亚胺法合成的OVA-DES免疫小白鼠,制备抗DES的特异性抗体,分别用混合酸酐法合成的BSA-DES和碳二亚胺法合成的BSA-DES作为包被原检测抗体。检测结果表明:三种免疫原免疫动物,都产生了DES的特异性抗体,并建立了间接阻断ELISA法。这为残留DES酶免疫检测试剂盒的制备奠定了基础。     

In situ hybridization for the detection of transmissible gastroenteritis virus in pigs and comparison with other methods.

Archived formalin-fixed, paraffin-embedded tissues from 25 pigs naturally infected with transmissible gastroenteritis virus (TGEV) were examined by in situ hybridization for TGEV nucleic acid using a nonradioactive digoxigenin-labeled cDNA probe that targeted the nucleocapsid sequence of TGEV strains. The results of in situ hybridization for the detection of TGEV were compared with virus isolation (VI), a fluorescent antibody test (FAT), and transmission electron microscopy (TEM). VI, FAT, and TEM were tested over a course of time before the in situ hybridization was performed. Positive hybridization signals were detected in duodenal, jejunal, and ileal enterocytes from 21 pigs. Hybridization signals were confined to the cytoplasm. Intestinal specimens from 25 piglets were evaluated by 4 tests. Twenty-one of 25 were positive by in situ hybridization. Of these 21 samples, 5 (24%) were positive for TGEV by all 4 tests, 15 (71%) were positive by FAT, 14 (67%) were positive by VI, and 6 (29%) were positive by TEM. In situ hybridization for the detection of TGEV in formalin-fixed, paraffin-embedded tissues provides a rapid means of confirmation of a histopathological diagnosis of TGEV without virus isolation, or when only formalin-fixed intestinal specimens were available.     

原位杂交法检测hsp mRNA在猪组织细胞中的分布

根据hsp70和hsp90 mRNA基因序列,设计并合成引物,将PCR扩增的基因片段克隆到pGEM-T载体,重组质粒经筛选、鉴定,利用体外转录系统,制作地高辛标记的RNA探针,建立检测hsps mRNA原位杂交方法。利用自建的原位杂交方法,对hsp70、hsp90 mRNA进行组织细胞定位研究。结果显示:hsp70 mRNA和hsp90 mRNA广泛分布于各组织细胞中,尤其在细胞核中相对集中,在肾小管上皮细胞胞浆中也呈强阳性着色。     

牛磺酸对马杜霉素中毒大鼠的保护作用

观察牛磺酸对大鼠马杜霉素中毒时的保护作用。将试验大鼠每天灌服马杜霉素进行染毒,且染毒前1 h腹腔注射牛磺酸保护,染毒5 d,继续注射牛磺酸2 d后处死,测定血清、肝脏、腿肌和心肌的丙二醛（MDA）含量、超氧化物歧化酶（SOD）活性、谷胱甘肽过氧化物酶（GSH-Px）活力和总抗氧化能力（T-AOC）。结果表明牛磺酸组的大鼠血清、肝脏、腿肌和心肌中SOD活性、GSH-Px活力、T-AOC均有所提高,MDA有所降低,与对照组、马杜霉素组比较,差异显著（P〈0.01,P〈0.05）。牛磺酸可以提高大鼠机体的抗氧化能力,对马杜霉素引起的脂质过氧化具有保护作用。     

双抗夹心—ELISA诊断牛隐孢子虫病

为了建立双抗体夹心—ＥＬＩＳＡ检测牛粪便中隐孢子虫卵囊抗原的方法。采用抗小球隐孢子虫（Ｃ．ｐａｒｖｕｍ）卵囊壁单克隆抗体,经对６０头份牛粪便样本分别进行抗酸染色和双抗夹心—ＥＬＩＳＡ检测,结果抗酸染色法检出１２头份有隐孢子虫卵囊,而ＥＬＩＳＡ除对抗酸染色阳性的１２份粪样判为阳性外,还对抗酸染色阴性的４份粪样判为阳性,且不与牛球虫、牛结肠小袋纤毛虫发生类属反应。此外,本试验在稀释液中加入ＥＤＴＡ,并增加了反应温度,使得试验在抗体包被板并封闭后３０ｍｉｎ结束整个检测过程。结果表明,双抗体夹心—ＥＬＩＳＡ是敏感性高、特异性强的诊断牛隐孢子虫病的方法。     

First outbreak of Trypanosoma evansi in camels in metropolitan France

The first outbreak of trypanosomosis caused by Trypanosoma evansi in camels in France was reported on a farm in the Aveyron Department. Five camels were imported from the Canary Islands to the farm in early July 2006, and trypanosomes were observed on a stained blood smear from one of them, which died in October. On further investigations, trypanosomes were observed in the blood of five camels, three of them indigenous to the farm and two that had been imported. On the basis of microscopical examination (morphological criteria and measurements) and serological results based on the card agglutination T evansi test and PCR typing, the parasites were identified as T evansi. After treatment with melarsomine, the infected camels rapidly became negative by parasitological tests and were negative two to four months later by serological tests. The parasite was probably transmitted by tabanids and Stomoxys calcitrans, which were abundant in July to September 2006. No parasites were observed in other animals on the farm or on neighbouring farms, but some of the sheep on these farms were positive by PCR or serology.     

Isolation of coronaviruses from neonatal calf diarrhoea in Great Britain and Denmark

Coronaviruses were isolated from neonatal calves with diarrhoea in Great Britain and Denmark. They were serially passed in gnotobiotic calves which developed acute diarrhoea. Pathological lesions were found in the small and large intestines. Coronaviruses were demonstrated by electron microscopic examination of the faeces and intestinal contents, immunofluorescent staining of sections of small and large intestine and by isolation in tracheal organ cultures. In early passages of the British coronavirus, particles of about 30 nm in diameter were observed in the faeces by electron microscopy. These particles were removed from the coronavirus preparations by cross-protection experiments in calves. The coronaviruses were morphologically and antigenically similar to the bovine coronavirus isolated in the United States and the British virus was adapted to replicate in calf kidney cell cultures.     

豆科绿肥对四川丘陵区橘园间作效应的初步研究

为明确豆科绿肥对四川丘陵区橘园产量、品质、产值及土壤肥力的影响,2011-2013年在四川省西充县进行了试验研究。结果表明：（1）橘园间作豆科作物柑橘产量比对照提高3.3%-5.7%、但增产不显著;（2）凡涉及间作大豆的模式,经济产值极显著提高、比对照增加14.3%-16.2%;（3）凡间种豆科绿肥的模式,柑橘品质和土壤养分都有明显改善,柑橘总糖提高13.1%-15.5%、可溶性固形物提高17.4%-20.2%、Vc 提高13.6%-16.3%、可滴定酸降低10.3%-11.8%,土壤有机质增加13.2%-15.9%、全氮增加6.3%-8.7%、全磷增加8.0%-10.6%、速效钾增加6.2%-8.7%。橘园间作豆科绿肥和间作大豆-绿肥的综合效应良好,可选择应用。     

Persorption of luminal antigenic molecule and its specific antibody via apoptotic epithelial cells of intestinal villi and Peyer's patches into peripheral blood in rats

The possibility of persorption of bovine serum albumin (BSA) molecules from mucous epithelial cells and its mechanism were investigated in rats orally pre-immunized by BSA for 14 consecutive days. In the small and large intestines, both the BSA antigen (BSA-Ag) and its specific antibody (SpAb) were absorbed by the epithelial cells at the late apoptotic stage (ApoEp), and were subsequently transcytosed by membranes of the small vesicles. The basal cytoplasms containing highly-concentrated BSA-Ag and SpAb were occasionally fragmented into small cytoplasmic droplets that were secreted into the lamina propria. In Peyer's patches, both BSA-Ag and SpAb were more actively absorbed and transcytosed toward the dome area by the ApoEp of the dome apex than by the M cells. BSA-Ag and SpAb were finally persorbed into the portal blood and lymph, but were never secreted into the bile. They were also engulfed by macrophage-like cells in the villous lamina propria, mesenteric lymph node and spleen, and by hepatocytes in the liver. These findings suggest that sensitized soluble luminal antigens are taken up by ApoEp in the small intestine and are finally persorbed into the peripheral blood. The uptake of luminal antigen might be mediated by its luminal SpAb.     

不同来源饲料级磷酸氢钙的质量研究

选择硫酸法和盐酸法生产的饲料级磷酸氢钙,对不同来源的饲料级磷酸氢钙的质量进行研究,包括颜色、容重、均匀度、pH、钙、总磷、游离水分的测定。结果表明:硫酸法生产的饲料级磷酸氢钙和盐酸法生产的饲料级磷酸氢钙的质量指标之间存在差异,硫酸法产品pH值高于盐酸法,而在钙含量和游离水含量上面则是盐酸法的产品高于硫酸法的产品。     

Growth and morphological characteristics of canine venereal tumor cells in vitro

Canine venereal tumor cells were grown in monolayer and tumor tissue fragments were maintained in vitro for 56 days in medium-199. Attachment and cell replication were evident within 17 hours and monolayer was obtained by the tenth day. Growth at first comprised mainly round cells with abundance of cytoplasm and vesicular nuclei, and a few spindle-shaped cells. Later cells became more elongated and like fibroblasts. Cell degeneration started by the 17th day and most were degenerated by the 24th day. Necrosis and depletion of cell population were prominent in tumor explants during the first 2 weeks. Distinct cell multiplication was evident by the 21st day and tumor fragments were repopulated with cells resembling the original tumor by the 56th day. Two distinct morphological cell types were seen: small cells with vesicular, round to oval nuclei and acidophilic cytoplasm; and the large cells with large hyperchromatic nuclei and acidophilic cytoplasm.     

狗牙根辐射诱变后代外部性状变异分析

对1997-2002年经过辐射诱变得到的狗牙根诱变后代的6个坪用性状指标的统计分析结果表明,1)不同的辐射诱变剂量处理的后代间坪用性状有显著差异,尤其在节间直径和密度上,6 800 rads处理的后代节间都比9 000 rads处理的后代粗,而密度是前者低于后者,2种剂量处理都可以显著降低草层高度;2)不同辐射诱变代数的后代间存在着差异,原始种源进行多代的辐射诱变,可以使得叶片显著变窄,草层高度显著降低,节间变细变长; 3)同一材料在相同辐射剂量诱变处理后匍匐茎不同节之间也存在显著的差异.     

Immunoreactive protein antigens of Mycoplasma pulmonis in experimentally infected rats

Mycoplasma pulmonis was cultured in modified Hayflick's medium, washed in 0.25 M NaCl, and solubilized by 2.5% sodium dodecyl sulfate. Protein antigens of M pulmonis separated by polyacrylamide-gel electrophoresis were blotted onto nitrocellulose strips. Specific-pathogen-free rats were inoculated intranasally with M pulmonis. The serum samples of these rats were obtained periodically and used to react with fractionated M pulmonis antigens which were fixed on the nitrocellulose strips. The antigen-antibody reactions were further recognized by 125I-labeled antiglobulin. Detection of immunoreactive antigens was obtained by autoradiography. Antibody response was not detected in serum obtained 7 days after rats were inoculated, and by 14 days, a slight response to several proteins was found. At 28 days after rats were inoculated, many immunoreactive antigens were detected. Generally, antibodies against antigens of moderate to low molecular weight appeared early in the infection, and antibodies against antigens of high molecular weight appeared late. Important immunoreactive antigens thus identified can readily be distinguished from more than 58 different M pulmonis antigens detectable by sodium dodecyl sulfate polyacrylamide-gel electrophoresis. The humoral antibody response was measured by an enzyme-linked immunosorbent assay. The immunoglobulin G antibodies were initially detected at low level at 7 days after rats were inoculated. These humoral antibody responses reached maximum by 28 days. The increase in serum antibody titer corresponded with numbers of immunoreactive antigens detected by immunoradio-binding assay. The information gained by this investigation may improve our understanding of the antigenicity of M pulmonis and the immune response of rats exposed to M pulmonis.     

波德代羊及其杂种羊血液蛋白多态性研究

运用聚丙烯酰胺凝胶电泳技术对首次引入我国的肉用品种绵羊波德代及其杂种一、二、三代和当地蒙古羊的血液蛋白(酶)多态性进行了检测分析。结果表明:波德代羊及其杂种和蒙古羊在Hb、Tf、Es三个基因座上存在多态性。其中Hb和Es的基因座均由两个等位基因控制,而Tf的基因座则由三个等位基因控制。从三个基因座的Nei氏平均基因杂合度估计绵羊品种内遗传变异,发现以蒙古羊为最低,其杂合度为0.3903。品种聚类分析也符合群体遗传学原理。     

THE ISOLATION OF LENTOGENIC STRAINS OF NEWCASTLE DISEASE VIRUS IN AUSTRALIA

SUMMARY Twelve isolations of Newcastle disease virus were made from 77 clinical samples from chickens with conjunctivitis, respiratory disease, proventriculitis and bursal atrophy. Nine of the Isolations were made from chickens with conjunctivitis. The viruses were identified as Newcastle disease virus by inhibition of their haemagglutinins with specific antiserum to Newcastle disease virus. The viruses failed to kill chicken embryos after inoculation into the allantoic cavity and they were judged to be lentogenic strains. There was no evidence that the Newcastle disease viruses were responsible for any of the clinical conditions from which they were isolated. The presence of other agents in 10 of the samples was indicated by reduced production of haemagglutinin in allantoic fluids of infected embryos, by deaths of infected embryos, by the production of cytopathic changes in avian cell cultures and by electron microscopy. Three isolations of infectious bronchitis virus, 2 of avian adenovirus and one of avian reovirus were made. Other samples were suspected of containing infectious bronchitis virus and mycoplasmas, but these were not isolated. The Newcastle disease viruses failed to produce plaques in chicken embryo fibroblast cell cultures and they were separated from the contaminating agents by haemagglutination and elution followed by passage at terminal dilution in chick embryos. No Newcastle disease virus was isolated from 60 caecal tonsils and 60 lung samples from 9-week-old broiler chickens. Eight lung samples yielded mycoplasmas that caused haemadsorption in chicken cell cultures. The mycoplasmas were probably Mycoplasma gallisepticum.     

Acute phase proteins in milk in naturally acquired bovine mastitis caused by different pathogens

The concentrations of haptoglobin (Hp) and serum amyloid A (SAA) and the activity of N-acetyl-β-D-glucosaminidase (NAGase) in milk from 234 cows with spontaneous mastitis caused by different pathogens were measured to assess whether they corresponded with the clinical signs of mastitis and whether there were any differences between pathogens. Ninety-eight of the cows had clinical mastitis and 136 had subclinical mastitis. There were statistically significant positive correlations between the concentrations of SAA and Hp and the activity of NAGase. Significant differences in the concentrations of acute phase proteins and NAGase activity were found in milk from cows with mastitis caused by different pathogens. The highest concentrations of Hp and NAGase were found in cases of mastitis caused by Escherichia coli and Arcanobacterium pyogenes, and the lowest concentrations were from cases of mastitis caused by coagulase-negative staphylococci. Very low SAA concentrations were found in milk from the cases caused by A pyogenes, in contrast to cases caused by other major mastitis pathogens. The median concentration of SAA was over 10 times higher in cases of mastitis caused by E coli than in mastitis caused by other pathogens. There were significant differences in the mean Hp concentration and NAGase activity between clinical and subclinical mastitis. In approximately one-third of the samples, the Hp concentration was below the detection limit, potentially compromising the use of Hp as a mastitis marker.     

Experimental tracheal and conjunctival infections with crytosporidium sp. in pigs

Tracheal and conjunctival infections with Cryptosporidium were established in pigs by inoculation of oocysts into the trachea and onto the conjunctival sacs. The protozoa were found attached to epithelial cells by an electron-dense band and a folded, vacuolated feeder organelle. They were situated in a parasitophorous vacuole surrounded by a double-layered membrane covered by glycocalyx. Trophozoites, schizonts, merozoites, macrogameters and oocysts could be demonstrated. In addition to normal stages of the life-cycle, degenerate stages were found.The infections with Cryptosporidium were characterized by focal destruction and loss of epithelial cells. Numerous intraepithelial lymphocytes were associated with affected foci, as were infiltrations with lymphocytes, monocytes, and macrophages.     

The immune response of the chick following viral vaccinations and immunization with sheep red blood cells

The effects of viral vaccinations and immunization with sheep red blood cells (SRBC) on the humoral response of pullets were investigated. Pullets were vaccinated with Marek's disease virus, Newcastle disease virus (NDV), infectious bronchitis virus (IBV), and infectious bursal disease virus at appropriate ages used in commercial practice. At seven weeks, the pullets were intramuscularly immunized with SRBC. NDV and IBV antibodies were detected by hemagglutination-inhibition tests. Hemagglutination (HA) titers were established against SRBC. IBV antibody titers were not affected by vaccination or by immunization with SRBC. NDV antibody titers were significantly increased by vaccination and by immunization with SRBC. The SRBC agglutinin response was also positively affected by vaccination. The HA titer increase consisted of a rise in 2-mercaptoethanol (2-ME)-sensitive antibodies and a fall in 2-ME-resistant antibodies.     

Immunohistochemical detection of fungal elements in the tissues of goslings with pulmonary and systemic aspergillosis

Nineteen goslings with pulmonary and systemic aspergillosis were the subject of the study. The lungs and air sacs were the main sites affected by the disease, and were generally characterised by diffuse yellowish-white granulomas. In 7 cases with pulmonary and air-sac involvement the granulomas were scattered to the serosal linings of the gastrointestinal and upper respiratory tracts, to the liver, spleen and kidneys, and in two cases also to the bursa of Fabricius, musculus (m.) longus colli and adventitia of aorta. The granulomas were often characterised by a necrotic centre surrounded by heterophils, macrophages, lymphocyte and plasma cells, and in late granulomas by multinucleated foreign-body giant cells, and again by an outer thin fibrous capsule. Numerous fungal hyphae were found within the necrotic debris of the granulomas by Gridley and PAS staining techniques. Immunohistochemistry reliably confirmed aspergillosis in all of the cases. Fungal elements in the lungs of goslings severely affected by the disease stained heavily within the centre of the granulomas, whereas few antigens reacted in the chronic cases. Fungal fragments, which were not discernible using routine fungal stains, reacted clearly in the cytoplasm of macrophages and giant cells. Thus, although fungal elements within the granulomas were histologically indicative of aspergillosis, immunohistochemistry also had to be applied to obtain a definitive diagnosis of the disease and to differentiate it from many of the filamentous fungi.