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1.
通过一年多临床实践及走访调查,对吉林市左家镇引起母牛繁殖障碍的常见原因做出了较为全面的了解,并且通过临床防治总结出较为科学有效的防治对策。  相似文献   
2.
Vitamin E is a primary chain‐breaking antioxidant that prevents cyclic propagation of lipid peroxidation. Across species, vitamin E is essential for normal neuromuscular function by acting as a potent antioxidant, as well as by modulating the expression of certain genes, inhibiting platelet aggregation and stabilizing plasma membranes. This review focuses on vitamin E structure, absorption, metabolism, current equine dietary recommendations, the interplay between antioxidants and exercise, a discussion of the necessity of vitamin E supplementation in the horse above the Nutritional Research Council (NRC) 2007 requirements, and a review of equine diseases that are associated with a vitamin E deficiency. Particular emphasis is placed on the proteins involved in vitamin E absorption, transport, and metabolism as potential candidates for vitamin E‐associated diseases across species.  相似文献   
3.
The study was conducted to estimate the proportion of reproductive disorders and to determine factors affecting reproductive performance of crossbred dairy cows under four different production systems in the central highlands of Ethiopia. The principal postpartum reproductive disorders were retained fetal membranes (14.7%) and uterine infection (15.5%). Anoestrus was the major postpartum reproductive problem in the mixed crop–livestock production system (38.6%) and was significantly associated with this production system. Apart from anoestrus, the occurrence of reproductive disorders was not significantly associated with a production system. Most of the reproductive disorders occurred as a complex rather than as a single abnormality. Two or more abnormal conditions were seen in 11.4% of the cases. Each reproductive trait measured was affected adversely by reproductive disorders. Cows with reproductive disorders in each production system, lactation group and suckling and non-suckling group had longer intervals from calving to first service and to conception (p < 0.001) and required more services per conception (p < 0.001). Pregnancy rate and conception to first service were 84.7% and 51.7%, respectively, for cows without reproductive health problems; and 64.2% and 15.1%, respectively, for cows with reproductive disorders (p < 0.001). Overall, intervals from calving to first service were shorter (p < 0.05) than in younger cows. Intervals from calving to first service and to conception were longer in suckling than in non-suckling cows (p > 0.05). Cows with a good body condition score (>3.5) at calving had shorter calving to first service and conception intervals than cows in poor condition (p < 0.001). The results showed that reproductive abnormalities, coupled with poor body condition, are important factors that contributed to reproductive inefficiency. An appropriate reproductive health management, a reliable artificial insemination service and supplementary feeding could be the management options to reduce or alleviate some of the problems.  相似文献   
4.
The relationships between the herd-level distribution of udder health measures (traumatic, physical, functional and congestive udder disorders, clinical mastitis and somatic cell counts (SCC) greater than 400 × 103, ml−1) and farm (general hygiene, milking practices and housing system) and aggregated individual characteristics were studied by canonical correspondence analysis (CCA). This is a correspondence-analysis technique in which the axes representing disease patterns are expressed as linear combinations of potentially explanatory variables. These main axes can be drawn so that the distribution of diseases for combinations of the main-explanatory managerial variables can be visualized. The type of quarantine for newcomers, type of animal housing, presence of shelter at pasture, use of udder towel before milking, milk production and loss of body condition after calving, were strongly correlated with udder health status. Mastitis and physical udder disorders were associated with the combination of no introduction of replacement heifers and low loss of body condition after calving. Congestive disorders were more common on farms when no quarantine for newcomers was combined with high loss of body condition after calving. Higher clinical and subclinical mastitis incidence risks were associated with the combination of no udder towel, loose housing with high animal density and high milk production. In most cases, clinical mastitis and high SCC were explained by the same covariates but with contrasting levels of those covariates.  相似文献   
5.
REASON FOR PERFORMING STUDY: Tachykinins have profound effects on equine intestinal motility, but the distribution of the neurokinin receptors (NKRs) through which they act is unknown. This study reports the distribution of one of these receptors, the neurokinin-1 receptor (NK1R), in smooth muscle throughout the equine intestinal tract. OBJECTIVES: To quantify the distribution of the NK1R, based upon mRNA expression, in smooth muscle of different regions of the equine intestinal tract. METHODS: Nine regions of the intestinal tract were sampled in 5 mature horses. Total RNA was isolated from smooth muscle and reverse transcribed; NK1R mRNA was then quantified using real-time PCR. RESULTS: NK1R mRNA was found at all levels of the sampled intestinal tract. The smooth muscle of the proximal small intestine and the ventral colon exhibited the highest level of NK1R mRNA expression in the equine intestinal tract. CONCLUSIONS: Tachykinins probably affect intestinal contractility and propulsion in the proximal small intestine and in the ventral colon.  相似文献   
6.
This study was designed to evaluate the quality of data from computerized medical record abstracts at the Veterinary Teaching Hospital, Ontario Veterinary College. Information in the paper medical record (registration, physical exam, daily progress, laboratory, radiology, anaesthesia and surgery forms), the summary sheet, and the computerized record were compared. A random sample of 100 patient visits from a subset of visits that were identified as all possible dog or cat elective-surgery visits in the computerized records from 1983 through 1991 were used. Clinicians were responsible for summarizing the medical record on the summary sheet and health record technicians entered the information from the summary sheet into the computer record. Most of the discrepancies (n = 33) noted for diagnoses, procedures or complications were due to the lack of transfer of information from the paper forms to the summary sheet. Although the medical record technicians detected and entered some of these (n = 10), most were not entered into the computerized records. The next most-common discrepancies (n = 5) were due to the clinician writing a different entry on the summary sheet than was present on the other paper record forms. Only one record had a miscoded diagnosis and three had miscoded procedures. Misfiled forms in the medical record folders of two patients resulted in one incorrect diagnosis and one incorrect procedure recorded in the computer record. When any discrepancy between the paper and computer record for diagnoses, procedures or complications was considered, 41% of the visits had discrepancies (46% dogs; 36% cats). The percentage varied by surgery status: non-elective surgeries 82%, elective surgeries 37% and non-surgical visits 29%. There was no obvious time trend. The completeness and accuracy of information in the database was inadequate for the intended research on post-operative complications following elective surgeries.  相似文献   
7.
Syringomyelia: current concepts in pathogenesis, diagnosis, and treatment   总被引:6,自引:0,他引:6  
Syringomyelia is a condition that results in fluid-containing cavities within the parenchyma of the spinal cord as a consequence of altered cerebrospinal fluid dynamics. This review discusses the history and the classification of the disorder, the current theories of pathogenesis, and the advanced imaging modalities used in the diagnosis. The intramedullary pulse pressure theory (a new pathophysiologic concept of syringomyelia) also is presented. In addition, the current understanding of the painful nature of this condition is discussed and the current trends in medical and surgical management are reviewed.  相似文献   
8.
9.
试验旨在了解广西猪主要病毒性繁殖障碍疫病的发生态势,为预防和控制此类疫病提供科学依据。采用RT-PCR/PCR方法对2014年3月至2018年2月采自广西的349份流产胎儿样品进行猪瘟病毒(CSFV)、猪繁殖与呼吸综合征病毒(PRRSV)、猪圆环病毒2型(PCV2)、猪伪狂犬病病毒(PRV)、猪细小病毒(PPV)及猪乙型脑炎病毒(JEV)6种主要病毒性繁殖障碍疫病病原的检测并分析其阳性检出率在不同年份、季节之间的差异及病原混合感染情况。结果显示,2014-2017年,6种病原的猪场阳性率从高到低依次为JEV(36.00%)、PRRSV(16.00%)、PCV2(9.00%)、PRV(7.00%)、PPV(6.00%)和CFSV(5.00%),样品阳性检出率从高到低依次为JEV(27.06%)、PRRSV(6.18%)、PRV(5.88%)、PCV2(3.82%)、CSFV(2.35%)和PPV(2.35%)。季节因素对6种病毒性繁殖障碍疫病的发生有一定影响:JEV在夏季、秋季检出率较高,春季、冬季检出率较低;PRRSV一年四季检出率均较高,且无明显差异;PCV2在春季检出率较高,其次是夏季和冬季,秋季检出率较低;PRV在春季、冬季检出率较高,夏季、秋季检出率均为0;PPV在夏季检出率较高,其次是春季和秋季,冬季检出率为0;CSFV在冬季检出率最高,其次是夏季,春季和秋季检出率均为0。流产胎儿以单一感染为主,6种病毒均存在不同程度单一感染情况,单一感染率JEV最高(23.82%)、PCV2最低(0.59%);混合感染以双重感染为主,其中以2016年双重感染情况较多,且感染组合多样;三重感染情况较少、仅在2016年送检样品中发现1例,未发现四重及四重以上感染情况。调查结果表明,2014-2017年,JEV均有较高的阳性检出率,已成为广西部分猪场母猪流产最主要病毒性病原。PRRSV和PRV仍是目前引起广西猪场母猪流产的主要病毒性病原。  相似文献   
10.
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