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91.
92.
This study was designed to investigate the effects of weaning age on specific components of the adaptive immune system in pigs. Twenty-three crossbred pigs were randomly assigned to 1 of 3 treatments: weaning at 14 (14D, n = 8), 21 (21D, n = 7), or 28 (28D, n = 8) d of age. Peripheral blood samples, obtained when pigs were 13, 15, 20, 22, 27, 29, and 35 d of age, were analyzed for peripheral blood cell percentages and concentrations of neutrophils, lymphocytes, T cell subsets, mature B cells, and plasma cortisol concentrations. For each of the 3 groups, weaning increased plasma cortisol concentrations (P < 0.001) and reduced BW percentage change (P < 0.017). Lymphocyte concentrations displayed a treatment effect for the 14D (P = 0.074) and 28D (P = 0.014) groups. Albeit inconsistent, lymphocyte concentrations were less in weaned pigs on the day after weaning than in pigs remaining on the sow or weaned at a younger age. Specifically, mature B cells (CD21(+)) and CD4(+)CD8(+) cells decreased (P < 0.05) after weaning at 28 d of age. Other differences occurred among treatments; however, the differences apparently were not associated with weaning. Based upon the immunological measures used in the present study, there was not an explicit benefit to the adaptive immune system for any weaning age. Early weaning did not negatively affect the adaptive immunological competence of pigs as determined by changes in populations of immune cells.  相似文献   
93.
Diabetes mellitus is the most common endocrine disturbance of domestic carnivores and can cause autonomic neurological disorders, although these are still poorly understood in veterinary medicine. There is little information available on the quantitative adaptation mechanisms of the sympathetic ganglia during diabetes mellitus in domestic mammals. By combining morphometric methods and NADPH-diaphorase staining (as a possible marker for nitric oxide producing neurons), type I diabetes mellitus-related morphoquantitative changes were investigated in the celiac ganglion neurons in dogs. Twelve left celiac ganglia from adult female German shepherd dogs were examined: six ganglia were from non-diabetic and six from diabetic subjects. Consistent hypertrophy of the ganglia was noted in diabetic animals with increase of 55% in length, 53% in width, and 61.5% in thickness. The ordinary microstructure of the ganglia was modified leading to an uneven distribution of the ganglionic units and a more evident distribution of axon fascicles. In contrast to non-diabetic dogs, there was a lack of NADPH-diaphorase perikarial labelling in the celiac ganglion neurons of diabetic animals. The morphometric study showed that both the neuronal and nuclear sizes were significantly larger in diabetic dogs (1.3 and 1.39 times, respectively). The profile density and area fraction of NADPH-diaphorase-reactive celiac ganglion neurons were significantly larger (1.35 and 1.48 times, respectively) in non-diabetic dogs compared to NADPH-diaphorase-non-reactive celiac ganglion neurons in diabetic dogs. Although this study suggests that diabetic neuropathy is associated with neuronal hypertrophy, controversy remains over the possibility of ongoing neuronal loss and the functional interrelationship between them. It is unclear whether neuronal hypertrophy could be a compensation mechanism for a putative neuronal loss during the diabetes mellitus.  相似文献   
94.
A Robertsonian centric fusion between chromosomes 1 and 25 in Blonde d'Aquitaine cattle in New Zealand is reported. This fused chromosome is the same as the widely reported 1/29 translocation chromosome with the difference in the numbering arising from inconsistencies in the G and R-banded cattle karyotypes of the International System for Cytogenetic Nomenclature of Domestic Animals, 1989.  相似文献   
95.
ABSTRACT The spread of Fusarium head blight of wheat from a small area inoculum source was examined in wheat plots (100, 625, or 2,500 m(2)) inoculated in the center with Gibberella zeae-colonized corn kernels or macro-conidia sprayed on heads at anthesis. With the first inoculation method, disease foci were produced from ascospores released from perithecia formed on inoculated kernels. With the second inoculation method, disease foci were produced by macroconidia directly applied to the heads. Some plots were misted during anthesis. Plots were divided into grids, and disease incidence on spikelets and seeds was assessed at the grid intersections. Isopath contour maps were constructed using an interpolation procedure based on a weighted least squares method. Disease gradients were constructed from the isopath contours in the direction parallel to average nightly wind vectors using an exponential model. This study was conducted over a 3-year period at two sites: one in Quebec and one in Ontario. Both inoculation methods resulted in a discrete, primary focus of head blight in each plot, with one or two smaller secondary foci in some plots. The highest incidence of disease on spikelets or seed was commonly displaced somewhat from the inoculum source, usually downwind. The gradient slopes of seed and spikelet infection ranged from -0.10 to -0.43 m(1) in plots with ascospore inoculum and from -0.48 to -0.79 m(1) in plots inoculated with macroconidia. Seed infection declined to 10% of the maximum within 5 to 22 m from the focal center in asco-spore-inoculated plots, and within 5 m in a macroconidia-inoculated plot. Gradients were usually steeper upwind compared with downwind of the inoculum source. In misted plots, incidence of disease was higher and more diffuse than in nonirrigated plots. Based on gradients and dispersal patterns, disease foci in plots inoculated with G. zeae-colonized corn kernels probably arose from airborne ascospores rather than from splash-borne macroconidia and were the result of infection events that occurred over a short period of time. Comparison of conidial- and ascospore-derived disease gradients indicated a lack of secondary infection, confirming that Fusarium head blight is primarily a monocyclic disease.  相似文献   
96.
本文旨在研究酪啡肽及其酪蛋白水解肽对早期断奶仔猪分泌型免疫球蛋白A(SIgA)和细胞因子水平的影响。24头仔公猪随机分为对照组(正常哺乳28d断奶)、试验Ⅰ组(添加β-酪啡肽-7)和试验Ⅱ组(添加酪蛋白酶解物)。试验组于21d断奶,再连续添加酪蛋白胃蛋白酶解液或β-酪啡肽-710d,每天2次(共20mL),至32d,3组动物各随机取6头同时剖杀,取血、胃食糜和空肠食糜。观察其血清IL-2、TNF-α和胃肠内容物中SIgA的含量变化。结果表明:添加酪蛋白水解液组仔猪血清中IL-2的水平比对照组高75.9%,差异极显著(P<0.01);试验Ⅰ组血清中IL-2水平比对照组高35.7%,差异显著(P<0.05)。血清中TNF-α水平试验组略低于对照组。在对照组、试验Ⅰ和Ⅱ组仔猪的空肠食糜中均检测到SIgA,平均含量分别为(6.48±0.85)ng/g、(6.30±0.85)ng/g和(8.71±0.54)ng/g。与对照组相比,试验Ⅱ组差异极显著(P<0.05);胃食糜中未检测到SIgA。提示乳源活性肽对早期断奶仔猪细胞免疫和黏膜免疫活性具有一定的促进作用。  相似文献   
97.
为了探讨地氟病黄牛血清钙磷和碱性磷酸酶(ALP) 活性及硒铜镁田间防治效果。32 头自然生长的高氟黄牛,随机分为4 组,每组8 头,其中1 组为高氟对照组;2 组为高氟黄牛每日添加025 mg/kg 硒( 亚硒酸钠) ;3 组为高氟黄牛每日添加15 mg/kg 铜( 硫酸铜) ;(4) 组为高氟黄牛每日添加025 mg/kg 硒+ 15 mg/kg 铜+ 1 mg/kg 镁( 硫酸镁) 。另设正常对照奶黄牛各8 头,连续饲喂83d ,分别于试验的0d 、30d 、83d 采样,检测血清钙、磷和ALP。结果表明,高氟黄牛血清ALP活性高于正常对照奶黄牛,血清钙磷变化不大。添加硒铜镁于不同时间,使高氟黄牛ALP活性下降,血钙也随之降低,血磷维持正常水平,说明高氟黄牛补充硒铜镁能防治地氟病,但但不能完全阻止骨质疏松,故应同时补钙。  相似文献   
98.
本研究旨在探讨肾素血管紧张素系统(renin-angiotensin system, RAS)在溃疡性结肠炎小鼠肠-血屏障损伤中发挥的作用。选取16只ICR小鼠,随机分为正常对照组(Control组)和葡聚糖硫酸钠盐处理组(DSS组),等体积灌胃生理盐水。试验至第4天,DSS组小鼠在饮用水中添加DSS(终浓度为4%)制造小鼠溃疡性结肠炎模型。期间每天记录小鼠体重、粪便性状和粪便隐血情况,并计算疾病活跃指数(disease activity index, DAI)。DSS饮用至第8天,所有小鼠采血后剖检,量取结肠长度,取结肠组织等样品。进行如下试验:1)HE染色观察结肠组织病理变化;2)ELISA法检测血液中血管内皮生长因子(vascular endothelial growth factor, VEGFA)及结肠组织中Ang1-7和AngⅡ的含量;3)Western blot检测结肠组织中血管紧张素转化酶2(angiotensin-coverting enzyme 2, ACE2)、血管紧张素转化酶(ACE)和质膜膜泡关联蛋白(plasmalemma vesicle associate...  相似文献   
99.
Isolation of chicken anaemia virus from broiler chickens in New Zealand   总被引:3,自引:0,他引:3  
Chicken anaemia virus was isolated for the first time in New Zealand from the New Zealand domestic chicken population. The virus was recovered from diseased birds in five separate flocks of broiler chickens aged between 14 and 33 days of age. Six isolates were obtained from bone marrow and lymphoid tissues using the MDCC-MSB1 cell line derived from Marek's disease lymphoma. All isolates were resistant to chloroform and survived exposure to 70 degrees C for 5 minutes. The main clinical features consistently associated with the disease outbreaks were increased mortality, yolk sac infections, sub-cutaneous haemorrhages and atrophy of the thymus. Fungal pneumonia occurred in two flocks, and gangrenous dermatitis as a result of bacterial infection in another flock. Microscopic examination showed atrophy of the thymus, reduced medullary haematopoiesis and inflammation resulting from secondary infections.  相似文献   
100.
Ocular and periorbital sarcoids and squamous cell carcinoma are common in equine practice. Extensive involvement of periorbital tissues often necessitates removal of the globe if the function of the eyelids can not be maintained with tumor removal alone. This report describes a modification of the standard enucleation or exenteration technique for cases in which there is insufficient skin to achieve primary closure following complete surgical excision. The caudal portion of the dorsal orbital rim is protuberant; partial excision with an osteotome facilitates skin closure by decreasing the size of the wound. Mesh expansion of skin via multiple rows or parallel stab incisions can also be used as an adjunct to facilitate closure. Four horses underwent enucleation or exenteration using the orbital rim resection and mesh skin expansion techniques for extensive periocular tumors that were unresponsive to prior treatments. Follow-up intervals ranged from 6 to 42 months and no horses had tumor regrowth.  相似文献   
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