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本着遵照标准,结合实际的原则,阐述了动物用防疫耳标强度指标和字迹附着力指标等主要质量指标的检测方法,并通过大量试验证实其具有简单、科学、有效等特点,在实际检测过程中具有一定的推广应用价值。  相似文献   
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The signalment, clinical and laboratory findings of surgical conditions, treatment, and outcome of 102 cases of descending colon disease in horses were reviewed. Abnormal conditions were categorized as enteroliths, impactions, strangulating lipomas, fecaliths, foreign body obstruction, volvulus, nephrosplenic entrapment, and other conditions. Eleven breed categories of horses were seen during this period. Arabians, ponies, and American miniature horses were more predisposed to descending colon disease than other breeds (P less than 0.05). Female horses and animals greater than 15 years old were more likely to be affected with descending colon disease, whereas horses less than 5 years old were less likely to be affected (P less than 0.05). More specifically, Arabians, Quarter Horses, and Thoroughbreds greater than 10 years old were breeds that were overrepresented when compared with the hospital population (P less than 0.05). Enteroliths were most commonly seen in horses between 5 and 10 years old (P less than 0.05) and were not seen in horses less than 2 years old. Enteroliths had a tendency to develop more commonly in Arabians and in female horses. Impactions affected horses greater than 15 years old (P less than 0.05) and had a greater tendency to affect ponies and American miniature horses. Female horses were more commonly affected by impaction than were males. Strangulating lipomas were commonly seen in horses greater than 15 years old (P less than 0.05) and more specifically female Quarter Horses (P less than 0.05). Fecaliths tended to be a disease of horses less than 1 year old or greater than 15 years old and affected males more commonly than females.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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With the aim of investigating properties of stallion seminal plasma to eventually improve semen-handling techniques, sperm motility and plasma membrane integrity were analysed in different fractions of the ejaculates after storage. Semen was collected using a computer-controlled automated phantom that separates the ejaculates into five successive cups. Samples containing seminal plasma and skim milk extender were compared with samples stored in skim milk extender after the removal of seminal plasma by centrifugation. Fractionated ejaculates were stored cooled for 24 h after dilution with extender (Expt 1) or frozen in liquid nitrogen (Expt 2). In Expt 1, cup 1 was pre-sperm fluid, cups 2 and 3 sperm-rich fractions, and cup 4 sperm-poor fractions. In Expt 2, cups 1 and 2 were sperm-rich fractions, and cups 3 and 4 sperm-poor fractions. One sample (WE) represented the whole ejaculate in both experiments. Motility parameters were determined with a Hamilton-Thorn Motility Analyzer, and plasma membrane integrity was assessed using carboxyfluorescein diacetate and propidium iodide staining and fluorescence microscopy. The removal of seminal plasma lowered motility values, but not plasma membrane integrity, in both experiments. No significant differences between cups were observed after cooled storage. The cups differed significantly in most post-thaw motility parameters, and the sperm-rich fraction showed higher post-thaw motility than the whole ejaculate.  相似文献   
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Captive breeding of birds threatened by extinction in zoological gardens or other closed aviary centres is one of the methods allowing their protection and gene pool preservation ex situ in vivo. Such birds are usually kept in captivity lifelong and serve as parents of several new generations that can be further released into natural environment, or males are used as semen donors for artificial insemination and gene banking. Therefore, the fecundity of such flocks (number of laid egg and spermatozoa quantity and quality) is very important. The aim of this study was to evaluate the usefulness of captive kept capercaillie (Tetrao urogallus L.) as semen donors in three subsequent reproductive seasons, based on the assessment of manually collected semen quality. Male response to dorso‐abdominal massage, ejaculate volume, sperm concentration, motility and morphology were evaluated individually at three succeeding years. Depending on individual male properties and year of collection, the number of positive reactions to semen collection attempts (i.e. ending with ejaculation) varied from 44.4% to 100.0%; single ejaculate volume ranged from 10 to 300 μl, spermatozoa concentration from 10 × 106 per ml to 3520 × 106 per ml and percentage of live morphologically normal spermatozoa from 19.3 to 80.3%. The highest average value (66.7) of semen quality factor (SQF) was noted for a 2‐year‐old male (varying from 1.9 to 258.1), while the lowest for ten‐ (4.8; varying from 0.1 to 17.0) and 7‐year‐old (6.6; varying between 0.6 and 13.6). Assuming that for AI purposes, the ejaculate quality has to be at minimum 10 SQF, obtained results indicate that majority of capercaillie kept in captivity, both young (2–3 years old) and older (up to 10 years old), can be valuable semen producers in succeeding seasons.  相似文献   
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