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海南自 1997年从泰国引种虎纹蛙以来 ,虎纹蛙的人工养殖发展迅速 ,现已有养蛙池近 6万口 (每口蛙池面积约 13m2 ) ,年产量 1万余吨 ,产值近 2亿元。不过 ,随着海南虎纹蛙养殖不断发展 ,相关病害也越来越多 ,其中 ,由脑膜炎败血黄杆菌引起的白内障综合症是当前海南虎纹蛙养殖中最为常见、危害最大、造成经济损失最严重的疾病。该病的主要特点为患病虎纹蛙先后出现白内障、歪头和腹水等症状 ,该病没有明显季节性 ,幼蛙和成蛙均可感染 ,传染性和危害性极强。由于从患病虎纹蛙中分离的病原菌 (脑膜炎败血黄杆菌 )对绝大多数抗生素均不敏感 ,常见… 相似文献
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通过解剖309只虎纹蛙,发现其中195只胃中没有食物残留,114只胃中有食物残留,残留食物的成分主要有中腹足目田螺科、蜘蛛目地蛛科、蜈蚣目蜈蚣科、直翅目蝼蛄科、直翅目蟋蟀科、鞘翅目瓢虫科、鞘翅目金龟子科、鳞翅目天蛾科、无尾目蛙科、十足目溪蟹科、直翅目蝗科、莎草目禾本科,其中蝗科23.3%、蝼蛄科22%、瓢虫科11%、溪蟹科9.39%、蟋蟀科9.39%、地蛛科9.39%、金龟子科4.21%、天蛾科4.21%、田螺科2.91%、蜈蚣科2.67%、蛙科1.94%。人工养殖虎纹蛙的食物均为颗粒状配合饲料。利用食物成分的差异可以区分养殖虎纹蛙和野生虎纹蛙。研究还发现虎纹蛙成蛙个体的大小与虎纹蛙对食物成分的摄食没有显著的差异,虎纹蛙成蛙个体性别与虎纹蛙对食物成分的摄食没有显著的差异。 相似文献
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虎纹蛙蝌蚪几种饵料的比较试验 总被引：1，自引：0，他引：1
以藻类，蛋黄，水蚤和异种蝌蚪为饵料，饲喂人工养殖下的虎纹蛙蝌蚪。结果表明虎纹蛙蝌蚪喜食活动的动物性饵料，且生长率高。我们认为水蚤是一种较为适宜的饵料。 相似文献
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虎纹蛙是近年来人工养殖较理想的蛙种之一。虎纹蛙是变温动物,温度对蛙生长的影响很大。留作制种的亲蛙必须经历漫长的冬眠期,如何使种蛙安全地度过冬眠期是大规模人工养殖虎纹蛙的重要问题。因此,应掌握以下技术要点:1越冬池早准备种蛙畦应建在室内或塑料大棚内,最好是土池,进排水方便,蓄水深度在0.5m左右。在土池的四壁上建一些深30cm以上的土洞,洞口在水下面之上紧挨水平面,洞道略向下倾斜,使洞底在水平面之下。洞底应平坦,比洞口稍大。室内应有升温设备能使室温在冬季也能稳定在10℃,最低不能低于7℃,室内不能有污染。2种蛙早选择越冬的… 相似文献
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蛤蚧具有补肾壮阳、益精血功效,能治疗肺结核,老人虚弱性喘咳,心脏性喘咳,神经衰弱等病。蛤蚧是国内外紧缺的一种贵重药材,市场需求量大,随着野生蛤蚧资源急剧减少,不少地方开展人工养殖蛤蚧,但在饲养研究中,普遍认为,蛤蚧人工养殖关键是解决其饲料问题,很多养殖户及单位因 相似文献
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驯养经济动物养殖及种群遗传多样性的研究方法 总被引：1，自引：1，他引：0
LIU Chang-qing 包阿东 LIU Shuai 吴宏梅 LU Tao-feng 张洪海 TANG Xue-xi 关伟军 MA Yue-hui 《中国畜牧兽医》2008,35(8):52-56
我国貉、银狐、北极狐、水貂、梅花鹿等野生动物养殖作为一项新兴的产业已成为建设新农村新的经济增长点,但是无论是野外资源的保护成效,还是人工驯养繁殖业的发展状况以及野生动物及其产品的经营利用秩序与社会需要和客观要求相比,还存在着相当大的差距。与野外环境中的种群比较,圈养种群是进行遗传学研究的最好的模型对象,对于研究野生种群近交与群体灭绝间的关系是非常合适的材料。目前国内外对于驯养经济动物与野生种群遗传多样性的研究主要集中于线粒体DNA、核糖体DNA、微卫星分子标记及主要组织相容性复合体等几个方面。作者针对目前国内外尤其是国内有关驯养经济动物养殖现状及其与野生种群形态、遗传多样性差异几个重要研究技术方面的研究进行了详细的论述和探讨,旨在通过利用我国养殖的野生小种群遗传学特性,为珍稀野生动物种群保护遗传学研究及加快国内经济动物养殖提供理论支持。 相似文献
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河麂(hydropotes inermis),俗称牙獐、獐子,属偶蹄目,为小型鹿科动物。河麂曾广泛分布于我国东部大陆近水区域,但由于人类活动的干扰,其栖息地遭到大范围破坏,导致野生种群数量也急剧下降,为了更好地保护野生河麂的资源,河麂已被列入国家二级保护动物。江苏大丰麂鹿国家自然保护区采取了人工养殖扩大河麂基础种群,然后实施有计划地放归大自然的模式,取得了满意效果。自1996年以来,我们先后收养哺育了数十只野生幼麂,并闯过了饲养、繁殖和疾病防制关,现对河麂人工养殖的初步探讨和研究报告如下。1河麂的形态及生活习性根据长期观察、统计,江… 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献