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991.
王文杰 《猪业科学》2020,37(9):54-56
良好的猪舍环境是维持动物健康的基础,实现养猪生产节本增效的重要途径。文章结合生长肥育猪饲养的特点,解析生长肥育猪舍环境管理的意义和作用,系统综述了猪舍地面的清洁、猪舍空气清洁度及温度和湿度的调节、适宜的光照条件、有害生物防治和其他应激源的控制等方面的技术和应用情况,对如何深化改善猪舍环境管理提出了建议。  相似文献   
992.
郑佳星  刘显军 《猪业科学》2020,37(11):34-36
非洲猪瘟(ASF)是由非洲猪瘟病毒(ASFV)引起的一种的热性、斑疹性、高度接触性的猪传染病。世界首例ASF于1909年在非洲肯尼亚被发现。由于其传染性强,且发病后致死率高,给生猪养殖带来极大的危害,且严重影响了畜牧经济的发展。特别是在全球禁抗背景下,提高猪只免疫力成为防控ASF的重要环节。文章就ASF特征、临床表现,就如何在禁抗下提高猪免疫力提出一些建议。  相似文献   
993.
本根据邯郸、邢台猪附红细胞体病的流行及治疗情况,提出了控制该病的措施及较合理的治疗方案。  相似文献   
994.
将猪脾制成匀浆,经透析袋透析,G—6漏斗除菌,即可获得粗制猪脾转移因子(T—P).经鉴定,猪脾转移因子的理化性质和生物学特性与国内外报道资料相符,表明制品达到国内外同类制品水平.  相似文献   
995.
NEAT1是一个长的非编码RNA,参与了免疫反应、paraspeckle形成以及mRNA的输出等生物学过程。本研究利用PCR-RFLP方法检测了猪(Susscrofa)NEAT1一处C1149G单核苷酸位点的多态性,在检测的猪品种中等位基因频率变异较大。关联分析结果表明,在长白猪群体中CC基因型个体,0日龄和17日龄猪瘟病毒(CSFV)抗体水平,0日龄平均红细胞体积和32日龄红细胞平均血红蛋白浓度显著高于GG或CG基因型;而32日龄的血小板分布宽度、血小板平均容积和大血小板比率则显著低于GG或CG基因型。实验结果可以为猪的分子标记和辅助育种提供参考。  相似文献   
996.
Adiponectin's beneficial effects are mediated by the AdipoR1 and AdipoR2 receptors (AdipoRs). The pig is a good model to study complex disorders such as obesity. We analyzed the expression of adiponectin, AdipoRs and some key molecules of energy metabolism (AMP-activated protein kinase α [AMPKα], p38 mitogen-activated protein kinase [p38 MAPK], and PPARα) in 2 pig breeds that displayed an opposite genetic behavior for energy metabolism: Casertana (CE), a fat-type animal, and Large White (LW), a lean-type animal. Muscle, liver, visceral and subcutaneous adipose tissues, and brain tissues were examined. The AdipoRs cDNA sequences were identical in the 2 breeds. AdipoRs mRNA expression, measured in all tissues, was significantly lower only in the 2 adipose tissues of CE pigs (P < 0.05). The muscle expression of AdipoRs, AMPKα, p38 MAPK, and PPARα was lower in CE than in LW animals (P < 0.01, P < 0.05, P < 0.01, P < 0.01, respectively). In liver, no molecule differed between breeds. The expression of both AdipoRs in visceral and subcutaneous adipose tissues was lower in CE pigs (P < 0.01). In brain, AdipoR1 and AMPKα expression was lower in CE pigs (P < 0.01), whereas AdipoR2 tended to be lower in CE than LW pigs (P = 0.05). In conclusion, our results suggest that tissue-specific downregulation of Adiponectin, AdipoRs, and of the key molecules of energy metabolism may be associated with the tendency of CE pigs to accumulate fat.  相似文献   
997.
During oocyte growth, the morphology of the nucleolus changes into a compact and homogenous structure. The compact nucleoli in full-grown oocytes are not stained by aceto-orcein staining or immunofluorescence staining. In this study, we developed a hematoxylin staining method for pig oocytes in whole-mount preparations to visualize the nucleoli. Nucleoli of growing and full-grown oocytes were stained blue with hematoxylin. Using this staining method, the changes in the oocyte nucleolus during maturation were examined. The nucleolar diameter gradually decreased in maturing oocytes (10.7 ± 0.1 μm to 9.0 ± 0.7 μm, P<0.05) before germinal vesicle breakdown (GVBD). The results suggest that the nucleolar volume of oocytes decreases before GVBD.  相似文献   
998.
The bacterium Coxiella burnetii has been detected in the fetal membranes, birth fluids and vaginal mucus, as well as in the milk and other excretions of several domestic mammals. The finding of C. burnetii in association with abortion, parturition and in the postpartum period has led to the hypothesis that C. burnetii causes a range of reproductive diseases. This review critically evaluates the scientific basis for this hypothesis in domestic mammals.The review demonstrates a solid evidence for the association between C. burnetii infection and sporadic cases of abortion, premature delivery, stillbirth and weak offspring in cattle, sheep and goats. C. burnetii induced in-herd epidemics of this complete expression of reproductive failure have been reported for sheep and goats, but not for cattle. The single entities occur only as part of the complex and not as single events such as generally increased stillbirth rate. Studies show that C. burnetii initially infects the placenta and that subsequent spread to the fetus may occur either haematogenous or by the amniotic-oral route. The consequences for the equine, porcine, canine and feline conceptus remains to the elucidated but that infection of the conceptus may occur is documented for most species. There is no solid evidence to support a hypothesis of C. burnetii causing disorders such as subfertility, endometritis/metritis, or retained fetal membranes in any kind of domestic animal species.There is a strong need to validate non-pathology based methods such as polymerase chain reaction for their use in diagnostic and research in relation to establishing C. burnetii as the cause of abortion and to adapt an appropriate study design and include adequate control animals when linking epidemiological findings to C. burnetii or when evaluating effects of vaccination in production herds.  相似文献   
999.

Background

Sepsis caused by Staphylococcus aureus often leads to brain microabscesses in humans. Animal models of haematogenous brain abscesses would be useful to study this condition in detail. Recently, we developed a model of S. aureus sepsis in pigs and here we report that brain microabscesses develop in pigs with such induced S. aureus sepsis.Twelve pigs were divided into three groups. Nine pigs received an intravenous inoculation of S. aureus once at time 0 h (group 1) or twice at time 0 h and 12 h (groups 2 and 3). In each group the fourth pig served as control. The pigs were euthanized at time 12 h (Group 1), 24 h (Group 2) and 48 h (Group 3) after the first inoculation. The brains were collected and examined histopathologically.

Results

All inoculated pigs developed sepsis and seven out of nine pigs developed brain microabscesses. The microabscesses contained S. aureus and were located in the prosencephalon and mesencephalon. Chorioditis and meningitis occurred from 12 h after inoculation.

Conclusions

Pigs with experimental S. aureus sepsis often develop brain microabscesses. The porcine brain pathology mirrors the findings in human sepsis patients. We therefore suggest the pig as a useful animal model of the development of brain microabscesses caused by S. aureus sepsis.  相似文献   
1000.

Background

Mycobacterioses in animals cause economical losses and certain Mycobacterium avium subspecies are regarded as potential zoonotic agents. The evaluation of the zoonotic risk caused by M. avium subspecies requires information about the quantities of Mycobacterium strains in infected animals. Because M. avium subspecies in pig tissues are difficult or even impossible to quantify by culturing, we tested the suitability of a culture-independent real-time quantitative PCR (qPCR) assay for this purpose.

Methods

Mycobacterial DNA was extracted from porcine tissues by a novel method and quantified by Mycobacterium genus specific qPCR assay targeting the 16S rRNA gene.

Results

The response of the qPCR assay to the amount of M. avium subspecies avium mixed with porcine liver was linear in the range of approximately log105 to log107Mycobacterium cells per 1 g of liver. The assay was validated with three other M. avium subspecies strains. When the assay was applied to porcine lymph nodes with or without visible lesions related to Mycobacterium avium subspecies infections, around 104–107 mycobacterial genomes per gram of lymph nodes were detected.

Conclusions

The qPCR assay was found to be suitable for the quantification of Mycobacterium avium subspecies in porcine lymph nodes and liver.  相似文献   
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