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61.
The purpose of this study was to evaluate the cationic trypsinogen gene in miniature schnauzers for possible mutations. Genetic mutations have been linked with hereditary pancreatitis in humans. Four miniature schnauzers were selected on the basis of a clinical history of pancreatitis. One healthy miniature schnauzer and 1 healthy mixed breed canine were enrolled as controls. DNA was extracted from these canines using a commercial kit. Primers were designed to amplify the entire canine cationic trypsinogen cDNA sequence. A polymerase chain reaction (PCR) was performed and products were purified and sequenced. All sequences were then compared. The healthy control canine, a healthy miniature schnauzer, and the 4 miniature schnauzers with pancreatitis showed identical sequences of the cationic trypsinogen gene to the published sequence. We conclude that, in contrast to humans with hereditary pancreatitis, mutations of the cationic trypsinogen gene do not play a major role in the genesis of pancreatitis in the miniature schnauzer.  相似文献   
62.
An inexpensive sedimentation chamber to obtain cytologic specimens of cerebrospinal fluid (CSF) is described. The device, which has a total cost of about $5.00 can be built in few minutes. The device permits the cytologic study of specimens of CSF in clinics, where because of economic constraints, a cytocentrifuge is not available. The device permits the study of the CSF cells on either air-dried or wet smears even under field conditions, and the results obtained are consistent. Also, the device permits to retrieve the cell-free fluid for its use in chemical or immunologic procedures.  相似文献   
63.
A total of 20 (14 females, six males) captive striped skunks (Mephitis mephitis) with miniature temperature dataloggers implanted free in the abdominal cavity were examined for reproductive performance and pathology because of implants. Eleven of 12 female skunks reproduced successfully 45.9+/-3.7 days after surgery to remove implanted dataloggers. The pregnancy rate of 91.7% (11/12) was much higher than other captive studies and was comparable with that of wild skunks. Eight striped skunks (six males, two females) that were euthanatized and necropsied after having implants in the abdominal cavity for 5 mo showed no apparent pathology associated with the implant. Implantation of the intraperitoneal devices did not lead to complications in abdominal tissues. Neither implant nor surgery affected reproduction. We conclude that implanted dataloggers can safely be used in physiologic studies of striped skunks or possibly other small carnivores in captive or field studies.  相似文献   
64.
The swine pathogen Actinobacillus pleuropneumoniae serotype 1 was investigated for its ability to adhere to swine, rat, and human buccal epithelial cells (BEC). The highest number of bacteria adhered was to swine BEC. This binding ability was affected by heating, extreme pH, treatment with sodium dodecyl sulfate, ethylenediamine tetraacetate, or periodate, and proteolysis, suggesting that cell-surface glycoproteins participate in adherence and that adherence is based mostly on ionic interactions. Mannose and swine fibronectin may play a direct role in this interaction. Convalescent-phase serum from naturally infected pigs inhibited the adhesion. There was a correlation between bacterial pathogenicity as well as host specificity and the capacity for adherence to swine BEC. Adhesion to swine BEC provides a convenient method to study in vitro the adherence of A. pleuropneumoniae and other pathogens of the pig respiratory tract.  相似文献   
65.
为筛选适宜保定地区栽植的早熟苹果品种,以嫁接在SH40中间砧上的不同早熟苹果品种(系)为试材,测定了不同品种(系)早熟苹果树体生长发育指标和果实品质。结果表明:除嘎啦早熟变异外,其他供试品种(系)树体生长较好,3年生时Xu2-7、Xu3-2树高330.0~352.5 cm,4年生时为394.0~417.5 cm,Xu3-2、藤牧1号、信浓红4年生为336.5~381.0 cm。4年生时,干径以Xu2-5最大;短枝、中枝、叶丛枝均以Xu2-5最多,长枝以Xu2-7最多,总枝量以Xu2-5最多;藤牧1号短枝所占比例最高(57.4%)。应用模糊综合评判法得出Xu2-5、Xu2-7、信浓红、藤牧1号果实品质较高。  相似文献   
66.
本试验旨在研究玉米青贮与花生秧配比对奶牛瘤胃中花生秧降解特性的影响。选择4头体重、生理状态、生产性能相近,装有永久瘤胃瘘管的中国荷斯坦奶牛,分别饲喂含有玉米青贮与花生秧不同配比的全混合日粮(TMR),3种TMR中玉米青贮与花生秧的干物质(DM)配比分别为3.9∶1.0(A组)、1.2∶1.0(B组)、0.4∶1.0(C组)。试验分3期进行,依次进行A、B、C组试验。每期预试15 d,采样期4 d;共57 d。采用尼龙袋瘤胃降解技术测定花生秧在奶牛瘤胃中DM、粗蛋白质(CP)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)的72 h瘤胃降解率,并求得目标养分的动态降解参数及有效降解率。结果表明:1)花生秧的DM在瘤胃中有效降解率为56.49%~59.62%,CP为40.45%~47.36%,NDF为33.26%~35.20%,ADF为36.31%~37.45%。2)B组DM的有效降解率显著高于C组(P0.05),极显著高于A组(P0.01);B、C组的CP有效降解率显著高于A组(P0.05)。3)B、C组的NDF快速降解部分含量显著高于A组(P0.05);3种TMR对花生秧粗NDF和ADF有效降解率无显著影响(P0.05)。由此可见,花生秧具有较高的饲用价值。本试验条件下,玉米青贮与花生秧DM配比为1.2∶1.0时,可有效提高花生秧DM和CP的瘤胃降解率。  相似文献   
67.
仔猪断奶后受到心理、营养、环境等多方面的刺激,导致应激反应,影响仔猪的采食量。固体饲粮代替母乳是最大的应激源,通过在母猪饲粮中添加香味剂对仔猪产前和产后进行香味剂印迹训练,使仔猪逐渐喜欢这种气味,降低其对添加相同香味剂饲粮的应激反应,并对有相同气味的饲粮有采食偏好,从而提高仔猪的采食量。本文对产前和产后香味剂印迹训练对仔猪断奶后采食偏好的影响及其机理进行综述,为养猪业相关试验研究提供理论依据。  相似文献   
68.
69.
Mycoplasma pneumonia of swine (MPS) lung lesions and immunogenic properties were compared between a Landrace line that was genetically selected for reduced incidence of pulmonary MPS lesions, and a non‐selected Landrace line. The MPS‐selected Landrace line showed significantly lower degrees of pulmonary MPS lesions compared with the non‐selected Landrace line. When changes in immunity before and after vaccination were compared, the percentage of B cells in the peripheral blood of the MPS‐selected Landrace line was significantly lower than that of the non‐selected line. Furthermore, the concentration of growth hormone and the mitogen activity of peripheral blood mononuclear cells in the MPS‐selected Landrace line showed significantly (P < 0.05) lower increases after vaccination than the non‐selected line. Conversely, the concentration of peripheral blood interferon (IFN)‐γ and salivary immunoglobulin A (IgA) after Mycoplasma hyopneumoniae vaccination was significantly higher in the MPS‐selected Landrace line than in the non‐selected line. Gene expression of toll‐like receptor (TLR)2 and TLR4 was significantly higher in the MPS‐selected Landrace line in immune tissues, with the exception of the hilar lymph nodes. The present results suggest that peripheral blood IFN‐γ, salivary IgA TLR2, and TLR4 are important immunological factors influencing the development of MPS lesions.  相似文献   
70.
Immunogenic properties and mycoplasmal pneumonia of swine (MPS) lung lesions were compared between the immunity‐selected Large White line and the non‐selected Large White line. The selected Large White line showed a higher level of pulmonary MPS lesions compared with the non‐selected Large White line. Subsequent to vaccination, the percentage of natural killer cells and T cells (CD3+CD4+CD8 and CD3+CD4?CD8+ T cells) were significantly increased in the non‐selected line but remained unchanged in the immunity‐selected Large White line. Secretion of Mycoplasma hyopneumoniae vaccine‐specific immunoblogulin G and phagocyte activity in peripheral blood were significantly higher in the immunity‐selected Large White line than in the non‐selected line. Expression of interleukin (IL)‐4 and IL‐6 messenger RNA in hilar lymph nodes was significantly lower in the immunity‐selected Large White line than in the non‐selected line. However, expression of IL‐10 in all immune tissues was significantly higher in the immunity‐selected Large White line. These results suggest that the selection for high immunity was not effective in increasing resistance to MPS lung lesions.  相似文献   
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