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31.
[Objective] The paper was to improve the efficiency and accuracy of early forecast of Lepidopteran oak-infesting pests.[Method] DNA barcoding technique was established for quick species identification using mitochondrial cytochrome C oxidase subunit Ⅰ(COⅠ) as the standard gene.This barcoding technique was used to amplify and sequence genomic DNA samples from eggs and pupae of 11 species of Lepidopteran pests collected from oak.[Result] The DNA barcoding standard genes of 594-708 bp were determined from eggs and pupae of Lepidopteran insects.There were differences of 0-2 bases in DNA barcode sequences between conspecific eggs and pupae,with the sequence identity of 99.7%-100%.The average content of A,T,G and C of DNA barcode sequences from Lepidopteran insects were 30.7%,38.5%,14.9% and 15.9%,respectively.The obtained DNA barcode sequences had 91.4%-100% identity and 0-8.6% difference degree with GenBank-deposited DNA barcode sequences from organisms of the genetically-closest relationship.Among them,DNA barcode sequences from egg and pupa samples of 10 Lepidopteran insects(No.1-20) had 99%-100% identity and 0-1.0% difference degree with homologous sequences in GenBank database,while the remaining samples(No.21-22) had high difference degree(8.6%) with homologous sequences.[Conclusion] The established DNA barcoding technique is an effeetive tool for species identification of Lepidopteran pests using genomic DNA from eggs and pupae of Lepidopteran insects. 相似文献
32.
对入境伴侣动物实施有效检疫,防止外来疫病传入国境,是口岸动物检疫部门一项重要工作。本文结合笔者多年实际工作经验,围绕目前我国入境伴侣动物检疫监管中存在的问题,积极探索行之有效的检疫监管新模式,以确保国境安全和人民健康。 相似文献
33.
Weng Q Shi Z Kawaguchi M Watanabe G Taya K 《The Journal of reproduction and development》2008,54(5):397-401
Characteristic daily increases in the plasma levels of luteinizing hormone (LH) are present every afternoon during lactation in golden hamsters. The objective of this study was to investigate the effect of the diurnal rhythm of increases in LH on expression of nerve growth factor (NGF), its receptors trkA and p75 and inhibin alpha-subunit in the ovarian interstitial cells of lactating golden hamsters. Both lactating and non-lactating groups of postpartum golden hamsters were used in this study. The expression of NGF, its receptors trkA and p75 and inhibin alpha-subunit were determined by immunohistochemistry. Positive staining of NGF, trkA and p75 was found in the interstitial cells of the lactating group, and no immunoreactivity for NGF, trkA or p75 was observed in the ovarian interstitial cells of the non-lactating group. In addition, immunostaining of inhibin alpha-subunit was also observed in the interstitial cells of the lactating group but not in those of the non-lactating group. Immunostaining of the inhibin/activin beta(A)- and beta(B)-subunits was observed in the granulosa cells of antral follicles, but not in the interstitial cells of the lactating and non-lactating animals. These results suggest that the diurnal rhythm increases in LH can induce expression of NGF, trkA, p75 and inhibin alpha-subunit in the ovarian interstitial cells of lactating golden hamsters and that NGF, its receptors trkA and p75 and inhibin alpha-subunit may have the capacity for autocrine or paracrine modulation of interstitial cell differentiation in golden hamsters. 相似文献
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37.
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
38.
Zhen-Zhu Ma Yu-Yang Cheng Sheng-Qi Wang Jian-Zhen Ge Huai-Ping Shi Jian-Cun Kou 《Journal of animal physiology and animal nutrition》2020,104(1):44-55
In this study, we investigated the effects of Saccharomyces cerevisiae (SC), Bacillus subtilis (BS) and Enterococcus faecalis (EF), singly and in combination, on the dry matter intake (DMI), milk production and composition, and faecal microflora of Saanen dairy goats. Fifty goats were randomly divided into five groups: (a) basal diet (control); (b) basal diet + SC; (c) basal diet + BS; (d) basal diet + EF; and (e) basal diet + mixed probiotics. Each treated animal received 5 g/d of probiotics for a total administration of 5 × 1,011 CFU/goat per day. The inclusion of B. subtilis and E. faecalis in the diet of lactating Saanen goats increased DMI (p < .05). Enhanced milk yield was observed with BS and EF. Milk fat percentage was significantly increased by feeding mixed probiotics compared with the control (p < .05); supplying SC, BS and mixed probiotics enhanced the protein percentage (p < .05). The milk lactose percentage in the SC and BS groups was higher than in the control (p < .05). The amount of milk total solids was higher after feeding EF or mixed probiotics than in the control group (p < .05). Non-fat solids showed no notable differences among groups (p > .05). There was no significant influence on gut bacterial abundance and diversity from adding these three probiotics, singly or in combination. Bacteroidales, Escherichia–Shigella and Christensenellaceae abundances were decreased by supplying these probiotics but Succinivibrionaceae increased. In conclusion, there were positive influences of probiotic feed supplementation on intake, milk performance and intestinal microecology. 相似文献
39.
高效液相色谱法检测泰乐菌素在肉鸡组织中的残留 总被引:4,自引:0,他引:4
将肉鸡的肌肉、肝脏、肾脏和脂肪组织制成匀浆,用乙腈、石油醚和二氯甲烷萃取、净化后,用乙腈定容。以乙腈- 甲醇- 0.005 m ol/ L磷酸二氢铵溶液(60∶30∶10)为流动相,用高效液相色谱检测。本法对溶解于乙腈中的泰乐菌素的最低检测限为 0.05 m g/ L,在肉鸡各种组织中的最低检测限为 0.10 m g/ L。标准曲线的线性范围为 0.10~6.40 m g/ L。泰乐菌素质量浓度为 0.10、0.80、6.40 m g/ L 时的批间变异系数分别为(2.3±0.2)% 、(1.9±1.3)% 、(2.6±0.9)% 。0.20、0.40、0.80 m g/ L 的泰乐菌素在以上 4 种组织的回收率均符合残留检测的要求。结果表明,本法是一种灵敏、精密、可靠的检测肉鸡组织中泰乐菌素残留的分析方法。 相似文献
40.
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