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一流行特点
石家庄市行唐某鸡场饲养蛋鸡20 000只,品种为海兰褐,180日龄鸡群产蛋到八成蛋就不涨了,周边也有个别鸡场发生类似现象.鸡群精神正常,每天检出软壳蛋、薄皮蛋300个左右,残次率远远高于正常,产蛋率82%已经维持有15天.在蛋鸡80多天和110天左右曾经发生过鸡滑液囊支原体感染,连续注射过2次抗生素. 相似文献
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蛋鸡脂肪肝出血综合征的诊治 总被引:1,自引:0,他引:1
蛋鸡脂肪肝出血综合征是一种脂类代谢紊乱疾病。其特征是肝脏细胞中沉积大量脂肪,表现为脂肪肝,有时肝脏出血。病鸡营养状况良好,产蛋减少,因为肝脏功能障碍或肝脏破裂出血突然死亡。本病主要发生于笼养蛋鸡,特别是产蛋率高或正处在产蛋高峰期的鸡群发病较严重。发病率通常为2%,5%,死亡率2%-3%左右,但个别鸡群死亡率高达15%~20%,产蛋下降30%-50%。给养鸡业带来严重的损失。 相似文献
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肠毒综合症主要是由寄生于鸡肠道黏膜细胞内的一种球虫与一些病毒、细菌病混合感染,加之气候变化异常,昼夜温差变化较大而引起。临床以腹泻、粪便中有未消化的饲料、采食量明显下降、生长缓慢、体重减轻、脱水和饲料报酬下降为特征。2005年6月某鸡场成年产蛋鸡群中发生了该病,经过发病情况调查、临床剖检诊断而确诊,采用敏感药物治疗后病情得到了控制。1发病情况该鸡场饲养海兰褐商品蛋鸡2000只,25周龄时个别鸡只出现了死亡,但整个鸡群精神较好,采食量无明显下降,看不到明显症状,只有个别鸡只鸡冠苍白,拉白色条状或粘液状粪便,粪便颜色微黄,… 相似文献
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《养殖与饲料.饲料世界》2021,(6)
鸡群感染脂肪肝综合征后的典型症状为蛋鸡在产蛋高峰时产蛋率突然下降,有的鸡只出现精神不振和食欲下降等症状,对病死鸡只剖检可见肝脏发生脂肪变性、肝破裂,腹腔内有大量的血凝块或血液,及时调整饲料配方以及在饲料中添加适量的亚硒酸钠和生物素等抗脂肪肝因子,能够有效防治鸡群感染脂肪肝综合征。 相似文献
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鸡的脂肪肝综合征 (FLS)发生于产蛋鸡 ,是以过度肥胖和产蛋下降为特征的一种代谢病。脂肪肝同时有肝出血的病例又被称为脂肪肝出血综合征 (FLHS)。本病主要发生于产蛋期的高产鸡群 ,死亡率高 ,给养禽业造成了很大经济损失。笔者对河南省周口市某鸡场鸡脂肪肝综合征进行了诊治 ,现将有关情况报告如下。1 发病情况2 0 0 2年 3月 ,我市北郊某养鸡厂饲养的 5 0 0 0只艾维茵蛋鸡于 15 6日龄时开始发病 ,且发病鸡连续不断。产蛋量突然减少 ,产蛋率下降了 5 6%左右 ,发病率达到 42 %。经采取一定的防治措施后 ,92 %已基本痊愈 ,恢复了正常的产… 相似文献
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肠毒综合症主要是由寄生于鸡肠道的粘膜细胞内的一种球虫与一些病毒、细菌病混合感染,加之气候变化异常,昼夜温差变化较大而引起。临床以腹泻、粪便中有未消化的饲料、采食量明显下降、生长缓慢、体重减轻、脱水和饲料报酬下降为特征。2005年6月某鸡场成年产蛋鸡群中发现了该病,经过发病情况调查、临床剖检诊断而确诊,采用敏感药物治疗后病情得到了控制。1发病情况该鸡场饲养海兰褐商品蛋鸡2000只,25周龄时个别鸡只出现了死亡,但整个鸡群精神较好,采食量无明显下降,看不到明显症状,只有个别鸡只鸡冠苍白,为拉白色条状或粘液状粪便,粪便颜色… 相似文献
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现将我市某蛋鸡场外购的两批雏鸡因免疫失败致临近开产时发生鸡马立克氏病的诊断报道如下:1发病情况该场分别从两个种鸡场购入两批不同品种蛋鸡苗。2000年11月10日从江苏某种鸡场购进绿壳蛋鸡苗5000羽,140日龄时开始发病,发病率10%,死亡率4%,2001年2月15日从上海某种鸡场购进海兰蛋鸡苗10000羽,100日龄也开始发病,发病率为6%,死亡率为3%。2临床症状两批病鸡的临床表现比较相似,均表现精神萎靡,饮、食欲停止,躯体消瘦,羽毛松乱、翅下垂,个别病鸡呈现一腿伸向前方,另一腿伸向后方。3… 相似文献
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1 流行特点
鸡传染性腺胃炎可水平传播,表现在某一个区域内发病很严重而另一个区域内没有该病的发生。传染性腺胃炎与品种和日龄无关系,无论是生长速度快的大肉鸡品种还是生长速度极慢的土鸡、野鸡、山鸡等都有该病的发生。各种日龄的鸡都可发生,肉鸡以25日龄的鸡群多,蛋鸡以开产期(即170日龄左右)的鸡为多,该病有垂直传染的现象。在同一鸡场中不同日龄、不同品种的鸡都有发生,但同一品种同一日龄饲喂不同厂家的饲料或饲料原料发病率和死亡率有较大差别。 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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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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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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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