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81.
奶牛体型线性性状与其成年奶当量相关与通径分析 总被引:3,自引:0,他引:3
本文对1990—1991年度双桥农场3个奶牛场603头荷斯坦奶牛体型线性性状评分与其成年奶当量进行了相关通径分析,数据采用dBASE Ⅱ进行管理,应用Turo-Basic编程在AST-286进行计算分析。分析表明:奶牛体型线性性状中,乳房深与成年奶当量呈较强负相关r=-0.4266;尻宽与产奶量呈正相关(r=0.2939);这二者是影响成年奶当量的主要性状。 相似文献
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83.
伪狂犬病毒在潜伏感染猪体内的组织分布 总被引:2,自引:0,他引:2
潜伏感染是猪伪狂犬病防治和净化工作中的重要障碍之一。本研究用伪狂犬病毒(PRV)gG-/LacZ+标记毒株感染经过PRV灭活疫苗免疫的PRV阴性仔猪,建立了猪伪狂犬病毒潜伏感染动物模型,再用地塞米松激活PRV在猪体内的潜伏感染。运用免疫组织化学SABC染色法研究了PRV在潜伏感染猪和潜伏感染激活猪体内部分组织的分布情况。结果显示,阳性细胞主要分布在神经系统的大脑、小脑、脑干、三叉神经和视神经以及非神经系统的扁桃体、肺和肾等部位。阳性细胞数量随着攻毒后时间的发展呈现减少的趋势,而注射地塞米松后,阳性细胞数量在上述组织中显著增加。 相似文献
84.
采用基质栽培试验,研究对羟基苯甲酸、肉桂酸对3月生巨尾桉9号苗木生长及叶片抗氧化酶活性的影响,结果表明:对羟基苯甲酸各处理浓度(10、50、100、500 mg/L)下的苗高增长量、地径增长量均显著高于对照,且在10 mg/L时,苗高增长量最大,为52.33 cm;肉桂酸10 mg/L时巨尾桉苗木苗高增长量较对照高,且随着其浓度的增加,苗高增长量和地径增长量均逐渐降低。对羟基苯甲酸、肉桂酸各浓度下巨尾桉9号苗木叶片叶绿素总含量均极显著低于对照,丙二醛含量略高于对照;对羟基苯甲酸、肉桂酸各浓度对巨尾桉9号叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)、多酚氧化酶(PPO)活性均具有一定的影响。对羟基苯甲酸10、50、100 mg/L及肉桂酸10 mg/L处理下的综合化感效应指数为正,对羟基苯甲酸500 mg/L及肉桂酸50、100、500 mg/L处理下的综合化感效应指数为负。可见,对羟基苯甲酸、肉桂酸对巨尾桉9号苗木的生长具有“低浓度促进、高浓度抑制”的规律,拐点浓度分别为100、10 mg/L;且在处理浓度相同时,肉桂酸的化感作用较对羟基苯甲酸强。 相似文献
85.
YANG Yang XU Hou-qiang CHEN Wei ZHOU Di XU Min ZHANG Qing-qing ZHAO Huan-ping SUN Cheng-juan WANG Yuan-yuan ZHANG Ming YANG Tao 《中国畜牧兽医》2017,44(12):3401-3409
The objective of this study was to clone PDK4 and FGF10 genes, and investigate the expression level of PDK4 and FGF10 genes mRNA in different tissues of Large White pig and Congjiang Xiang pig. The PDK4 and FGF10 genes were cloned by RT-PCR and analyzed by bioinformatics, the relative expression of PDK4 and FGF10 genes were detected by Real-time PCR. The results showed that the coding region of PDK4 gene was 1 224 bp, encoding 407 amino acids; The coding region of FGF10 gene was 636 bp and encoded 211 amino acids. The homologies of nucleotide sequences of PDK4 gene with sheep, horse and human were 93%, 92% and 91%,respectively. The homologies of nucleotide sequences of FGF10 gene with sheep, cattle, human and mouse were 94%,93%, 93% and 90%, respectively. The phylogenetic tree of PDK4 gene showed that the genetic relationship of Congjiang Xiang pig, cattle and sheep were very close, the phylogenetic tree of FGF10 gene indicated that the genetic relationship of Congjiang Xiang pig, cattle, sheep, human and macaque were very close, but the genetic relationship of Congjiang Xiang pig, rat and chicken were far away. Real-time PCR results showed that, in different tissues of Congjiang Xiang pig,PDK4 gene expression in kidney tissue was higher than other tissues, with a higher expression in stomach and adipose as well,FGF10 gene expression in stomach tissue was higher than other tissues, with a higher expression in kidney and adipose as well, but both of PDK4 and FGF10 genes expression were the lowest in longissimus dorsi. In different tissues of Large White pig, both of PDK4 and FGF10 genes were expressed the highest in adipose than other tissues, PDK4 gene expression in longissimus dorsi was the lowest, while the FGF10 gene expression the lowest in heart. This study successfully cloned the PDK4 and FGF10 genes of Large White pig and Congjiang Xiang pig,and detected the relative expression of PDK4 and FGF10 genes in different tissues of Large White pig and Congjiang Xiang pig, and also provided scientific basis for further study on regulation of PDK4 and FGF10 genes on lipid metabolism and deposition. 相似文献
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88.
Muhid A Robertson I Ng J Yang R Ryan U 《Veterinary journal (London, England : 1997)》2012,191(1):135-137
Two hundred and forty calf faecal samples from 16 Malaysian farms were screened by PCR for Giardia spp. The overall prevalence was 12.5% and the overall farm prevalence was 68.8% (11/16 farms). The prevalence in pre-weaned and weaned calves was 16.7% and 8.3%, respectively. Sequence analysis of 25 isolates identified all as G. duodenalis assemblage E. Management factors associated with an increased risk of infection with Giardia spp. included keeping weaned calves in pens with sand floors and calf age. Keeping pre-weaned calves in pens with concrete floors and calving in single cow calving areas decreased the risk. 相似文献
89.
以5种黄瓜主要病原菌作为诱导抗病因子,研究其对黄瓜主要病害的作用,结果发现黄瓜经病原菌诱导后,可以产生对诱导病原菌及其它病原菌引起病害的交互保护作用,并且诱导的交互保护作用与诱导浓度、诱导间隔期、不同品种存在相关性.诱导效果不随诱导接种浓度的升高而升高.在黑星病菌对霜霉病菌的诱导作用中,以浓度为1×102个/ml的黑星病菌孢子悬浮液的诱导效果最好,诱导间隔期为48h黄瓜黑星病菌对霜霉病的交互保护作用最明显,抗性品种的交互保护作用明显好于感病品种;炭疽病菌可诱导黄瓜有效抑制褐斑病的发生,但挑战接种褐斑病菌后,却促进了炭疽病的发生.诱导接种炭疽病菌后再挑战接种褐斑病菌12d,对褐斑病的防效为92.07%. 相似文献
90.
Hye Kwon Kim Jeong Sun Yang Hyoung Joon Moon Seong Jun Park Yuzi Luo Chul Seung Lee Dae Sub Song Bo Kyu Kang Soo Kyung Ann Chan Hyuk Jun Bong Kyun Park 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(2):121-130
The 23 open reading frame (ORF) 5 sequences of Korean type II porcine reproductive and respiratory syndrome virus (PRRSV) were collected from viremic sera from the (modified live vaccine) MLV-vaccinating and non-vaccinating farms from 2007 to 2008. The samples were phylogenetically analyzed with previous ORF5 sequences, including type I Korean PRRSV, and previously reported or collected sequences from 1997 to 2008. A MN184-like subgroup of type II Korean PRRSV was newly identified in the viremic sera collected from 2007 to 2008. And of the type I PRRSVs, one subgroup had 87.2~88.9% similarity with the Lelystad virus, showing a close relationship with the 27~2003 strain of Spain. The maximum parsimony tree of type II PRRSV from 1997 to 2008 showed that they had evolved to four lineages, subgroups 1, 2, 3 and 4. Most of the recently collected type II PRRSVs belonged to subgroup 4 (48%). The region of three B-cell epitopes and two T-cell epitopes of ORF5 amino acids sequences was considerably different from the MLV in subgroups 3 and 4. In conclusion, the existence of type I PRRSV, which was genetically different from Lelystad virus (Prototype of type I PRRSV), and heterologous type II PRRSVs of viremic pigs detected even in the MLV-vaccinating farms indicated the need for new vaccine approaches for the control of PRRSV in Korea. 相似文献