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61.
为进一步掌握乳牛隐孢子虫病在河南省的流行动态,从河南省郑州、开封、济源和鹤壁4个地区9个奶牛场采集12月龄以内的乳牛粪便样品582份,用饱和蔗糖溶液漂浮法和改良抗酸染色法进行检测。结果显示,隐孢子虫总感染率为26.12%(152/582)。其中,断乳前犊牛(5日龄至2月龄)隐孢子虫感染率为30.91%(51/165),断乳后犊牛(3~12月龄)感染率为24.22%(101/417)。依据形态数值初步鉴定为2种隐孢子虫,即微小隐孢子虫和安氏隐孢子虫。微小隐孢子虫在断乳前犊牛阳性样品中的比率为50.98%(26/51),在断乳后乳牛阳性样品中的比率为9.90%(10/101)。另外,饲养方式(断乳前犊牛单独隔离饲养和未隔离饲养)对断乳前犊牛2种隐孢子虫的感染率有显著影响。 相似文献
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63.
不同生境下陌上菜的形态解剖学比较 总被引:1,自引:0,他引:1
本研究首次采用GMA切片等方法对不同生境下陌上菜的形态结构进行了深入的研究。结果显示,陌上菜种苗发育具有水生植物的特征:种子及种苗需浸水萌发及发育,具下胚轴毛,胚根发育迟缓。成株的营养器官兼具水生及陆生植物的结构特征:完全陆生的植株和湿生植株的气生部位具有较厚角质层,发达的机械组织及较发达的通气组织。完全水生的植株和湿生植株浸水部位的角质层和机械组织不发达,但通气组织非常发达。生殖器官:完全陆生和湿生的植株具有闭锁和开放2种类型的花,而完全水生的植株仅具闭锁花,从而保证了这一物种在不同生境下均能正常结实。此外,陌上菜具有特立中央胎座。本研究首次揭示了陌上菜在不同生境下种苗发育、营养器官及生殖器官结构的变化,完善了陌上菜的形态学,为进一步研究母草科的系统学提供了形态学依据。 相似文献
64.
65.
从动物毛中提取DNA研究初探 总被引:6,自引:0,他引:6
利用蛋白酶K分解毛发蛋白,并使用酚和氧仿除去蛋白质杂质方法提取毛中DNA。结果测量获得的数据和曲线表明:动物脱落毛发以及从保存多年标本获得的毛发均可用来提取到具有一定纯度和数量的DNA,完全可以满足聚合酶链式反应(PCR)所需。 相似文献
66.
江西地方品种水牛产肉性能及肉品质分析研究 总被引:2,自引:1,他引:2
对18~24月龄鄱阳湖、峡江和信丰山地3个江西地方品种水牛各3头,进行肉用性能和牛肉主要营养养分的测定分析。结果表明,水牛肌肉肉色符合标准,且无PSE肉、DFD肉产生,符合优质肉牛标准;鄱阳湖水牛的胴体重、净肉重、胴体产肉率、Fe含量、Zn含量较高,显著高于信丰山地水牛(P<0.05);鄱阳湖水牛18种氨基酸含量除酪氨酸外均高于其它2个地方品种,其中天门冬氨酸、谷氨酸、丝氨酸、脯氨酸、丙氨酸、亮氨酸及胱氨酸含量显著高于信丰山地水牛(P<0.05),鲜味氨基酸、甜鲜味氨基酸含量显著高于信丰山地水牛(P<0.05);牛肉脂肪酸中花生酸含量在品种间存在显著差异(P<0.05),而其它各种脂肪酸含量、硬脂肪酸总含量和不饱和脂肪总含量在品种间均无显著差异(P>0.05)。 相似文献
67.
Shelan Liu Yong Yang Zhifeng Pang Ying Liu Huan Li Jian Cai Zhuoying Wu Yan Luo Yuhuan Tang Lihong Ying Shuwen Qin Ziping Miao Na Zhao Yijuan Chen Jinren Pan Shijian Li Zhao Yu Feng Ling Enfu Chen Zhiping Chen 《Zoonoses and public health》2023,70(1):93-102
A cluster of Chlamydia psittaci (C. psittaci) cases was reported in Zhejiang Province, China, 2019. This study evaluates the extent of the outbreak and determines the source of infection. Real-time PCR and sequencing of the ompA gene of C. psittaci were performed to identify the cases, the domesticated poultry and close contacts. The index patient was a 76-year-old woman with chronic vertigo, and Case 2 was a 64-year-old female farmer with herpes zoster. Both women bought psittaci-infected chickens or ducks from the same mobile street vendor and raised them for 10 days and 23 days before fever onset. There were no direct contact between the two women. C. psittaci test was positive for the two patients, one sick chicken, three healthy ducks and the vendor's chicken cage. Phylogenetic analysis showed that all seven C. psittaci positive samples carried identical ompA genotype A of C. psittaci. Of all of the patients' 148 close contacts, none tested positive for C. psittaci, or developed acute respiratory symptoms. Both patients were discharged after a 4-week hospital stay. In conclusion, the source of this cluster was the poultry infected with C. psittaci, which occasionally cause infections in farmers, but inter-human transmission seems unlikely. 相似文献
68.
To systematically explore the microbial diversity and function in the rumen of Chinese Simmental cattle,this experiment used 16S rRNA gene high-throughput sequencing technology to detect and analyze the rumen fluid samples of Simmental cattle (about 20 months old,the average weight was 550 kg),and its function was predicted by PICRUSt.The results showed that a total of 66 712 high-quality sequences were obtained from the Illumina Miseq sequencing platform,and 1 797 operational classification units (OTU) were obtained by cluster analysis.The taxonomic identification was divided into 13 phylums,20 classes,22 orders,33 families and 59 genuses;Firmicutes and Bacteroidetes were dominant bacteria,accounting for 62.46% and 22.45%,respectively;Based on the genus composition,[Eubacterium]_coprostanoligenes_group (9.16%),Ruminococcus_2 (7.90%),norank_f__Bacteroidales_RF16_group(6.23%),norank_f__Ruminococcaceae(4.79%),Rikenellaceae_RC9_gut_group(4.72%),norank_f_Bacteroidales_BS11_gut_group(4.49%),Ruminococcus_1(4.43%),etc.The PICRUSt function of the 16S rRNA genome predicted that the rumen flora function was mainly concentrated in carbohydrate transport and metabolism,and might contain a large amount of cellulose and lignin degrading enzyme genes.In summary,the high-throughput sequencing technology based on 16S rRNA gene fully revealed the diversity of rumen bacteria in Simmental cattle,and predicted that it was rich in protein decomposition and lignocellulose degrading enzymes.The basis of microbial cognition provided a reference for further research on rumen microbial functional genes closely related to some important nutritional and physiological functions. 相似文献
69.
Nan‐Xi Hu Mei Chen Yi‐Song Liu Qi Shi Bo Yang Huan‐Cheng Zhang Pi Cheng Qi Tang Zhao‐Ying Liu Jian‐Guo Zeng 《Journal of veterinary pharmacology and therapeutics》2019,42(2):197-206
Sanguinarine (SA) and chelerythrine (CHE) are the main active components of the phytogenic livestock feed additive, Sangrovit®. However, little information is available on the pharmacokinetics of Sangrovit® in poultry. The goal of this work was to study the pharmacokinetics of SA, CHE, and their metabolites, dihydrosanguinarine (DHSA) and dihydrochelerythrine (DHCHE), in 10 healthy female broiler chickens following oral (p.o.) administration of Sangrovit® and intravenous (i.v.) administration of a mixture of SA and CHE. The plasma samples were processed using two different simple protein precipitation methods because the parent drugs and metabolites are stable under different pH conditions. The absorption and metabolism of SA following p.o. administration were fast, with half‐life (t1/2) values of 1.05 ± 0.18 hr and 0.83 ± 0.10 hr for SA and DHSA, respectively. The maximum concentration (Cmax) of DHSA (2.49 ± 1.4 μg/L) was higher that of SA (1.89 ± 0.8 μg/L). The area under the concentration vs. time curve (AUC) values for SA and DHSA were 9.92 ± 5.4 and 6.08 ± 3.49 ng/ml hr, respectively. Following i.v. administration, the clearance (CL) of SA was 6.79 ± 0.63 (L·h?1·kg?1) with a t1/2 of 0.34 ± 0.13 hr. The AUC values for DHSA and DHCHE were 7.48 ± 1.05 and 0.52 ± 0.09 (ng/ml hr), respectively. These data suggested that Sangrovit® had low absorption and bioavailability in broiler chickens. The work reported here provides useful information on the pharmacokinetic behavior of Sangrovit® after p.o. and i.v. administration in broiler chickens, which is important for the evaluation of its use in poultry. 相似文献
70.
通过对草产业集群的经济功效与形成路径的研究,认为虽然产业集群一般都是自发形成的,但政府培育仍然可以发挥出较好的引导效果.论文同时对政府引导产业集群形成的路径进行了探讨. 相似文献