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991.
Nitrogen balance in barrows fed low-protein diets supplemented with essential amino acids 总被引:3,自引:0,他引:3
D. Deng R.L. Huang T.J. Li G.Y. Wu M.Y. Xie Z.R. Tang P. Kang Y.M. Zhang M.Z. Fan X.F. Kong Z. Ruan H. Xiong Z.Y. Deng Y.-L. Yin 《Livestock Science》2007,109(1-3):220-223
This study was conducted to determine the effect of addition of essential amino acids (EAA) to low-protein diets on N balance in barrows. Thirty barrows (Duroc × Yorkshire) with an initial BW of 36 kg were fed 5 corn- and soybean meal-based diets containing 13.6 to 18.2% crude protein (CP) for 10 d in a randomized complete block design. The 18.2% CP diet was formulated without addition of EAA (Lys, Met or Thr). The other diets contained 13.6 to 16.5% CP and were supplemented with EAA to provide 0.83% true digestible lysine equal to that in the 18.2% CP diet. Fecal, urinary, and total N excretion as well as N retention (g/d) decreased with decreasing dietary CP level (P < 0.01). The apparent digestibility of N was almost the same for the 18.2 and 16.5 CP diets, but the value was 2% higher (P = 0.07) than that for the 13.6% CP diet. These findings indicate that, compared with the 18.2% CP diets, supplementation with three EAA to the lowest-protein diets (13.6 CP) is inadequate for maximum intestinal protein digestion, amino acid absorption, or tissue protein deposition in growing barrows. 相似文献
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996.
基于RS和GIS的吉林省城乡居民地区划特征分析 总被引:3,自引:0,他引:3
探讨吉林省的城乡居民地的空间格局对于城镇建设和相关基础设施建设无疑具有很大的参考价值。本文以TM为数据源提取了吉林省居民地空间分布信息。在GIS技术支撑下,结合区划理论和聚落地理学说,分析了吉林省城乡居民地的空间格局。结果表明,吉林省城乡居民地空间分布区划为三个区,分别是东部区、中部区和西部区。中部区城镇居民地和农村居民地密集,且城镇化程度最高;东、西部区城镇居民地景观指数无明显差别,但农村居民地的景观指数明显有差别。从居民地分布类型来看,城镇居民地与农村居民地在各区内都呈随机分布,但其指示参数最近邻点指数还是体现出明显的区划差异。 相似文献
997.
M. A. G. Dela Paz P. H. Goodwin A. K. Raymundo E. Y. Ardales C. M. Vera Cruz 《Plant pathology》2006,55(6):756-765
One taxonomic characteristic of Bipolaris species is the bipolar germination of conidia, but conidia of Bipolaris oryzae , the causal pathogen of brown spot in rice, are regularly observed to show intercalary germination, a characteristic of Drechslera species. The effect of selection, culture media and culture age on type of conidial germination was determined for three brown spot isolates from Cavinti, San Pablo and Palawan in the Philippines, obtained from infected leaves showing typical disease symptoms. Based on the analyses of their ITS1, ITS2 and 5·8S rDNA nucleotide sequences, the local isolates were clearly identified as B. oryzae . Selection for colonies of the three isolates derived from single conidia with either bipolar or intercalary germination had no effect on the number of spores showing bipolar germination in subsequent cultures. Germination on seven different culture media was tested; of these, rabbit food agar and water agar increased the percentage of bipolar germination of conidia, although this varied between isolates. Incubation of the cultures of all three isolates for longer periods prior to harvesting conidia increased the percentage of bipolar-germinating conidia from c . 40 to c . 90% with 5-day-old and 30-day-old cultures, respectively. 相似文献
998.
Biological Control of Sclerotinia Diseases of Rapeseed by Aerial Applications of the Mycoparasite Coniothyrium minitans 总被引:1,自引:0,他引:1
G. Q. Li H. C. Huang H. J. Miao R. S. Erickson D. H. Jiang Y. N. Xiao 《European journal of plant pathology / European Foundation for Plant Pathology》2006,114(4):345-355
Indoor and field experiments were conducted to evaluate the efficacy of applying the mycoparasite Coniothyrium minitans to the aerial parts of rapeseed plants at the flowering stage to control sclerotinia diseases caused by Sclerotinia sclerotiorum. Under controlled conditions, a petal inoculation technique was used to determine the effect of conidial suspensions of C. minitans on suppression of sclerotinia leaf blight. Results showed that C. minitans was effective in inhibiting infection initiated by ascospores of S. sclerotiorum on flower petals by restricting mycelial growth of the pathogen. Suppression of lesion development was related to the conidial
concentration of C. minitans, with larger lesions at low concentration (5×103conidia ml−1), but smaller lesions at high concentration (5×104 conidia ml−1 or higher). When C. minitans-treated rapeseed leaves were inoculated with mycelia of S. sclerotiorum, C. minitans failed to prevent infection of leaves, but caused a significant reduction in number of sclerotia produced on the diseased
leaves. No significant difference in efficacy was detected between the two isolates of C. minitans, LRC 2137 and Chy-1, on the two rapeseed cultivars, Westar (spring type) and Zhongyou 821 (winter type). Results of field
trials showed a significant reduction of stem rot of rapeseed in four (1997, 1999, 2003 and 2004) out of five years by aerial
application of C. minitans, compared with controls. No significant difference in suppressive efficacy was observed between the treatments of C. minitans (106 conidia ml−1), C. minitans (106 conidia ml−1) + benomyl (50 μg ml−1) and benomyl (100 μg ml−1) in 2003, and between the treatments of C. minitans (106 conidia ml−1), C. minitans (106 conidia ml−1) + vinclozolin (100 μg ml−1) and vinclozolin (500 μg ml−1) in 2004. Sclerotia of S. sclerotiorum collected from diseased plants in plots treated with C. minitans in 1999, 2000 and 2003, or with C. minitans + benomyl in 2003 were infected by C. minitans at frequencies ranging from 21.3 to 54.5%. This study concludes that aerial spraying of C. minitans is an effective method for controlling sclerotinia diseases of rapeseed. 相似文献
999.
MO Jiayuan GAO Jiuyu FENG Lingli LI Yueyue TIAN Weilong LIU Xiaoxiao CHENG Feng LIANG Liang LEI Shuqiao WEN Wei LIANG Jing LAN Ganqiu 《中国畜牧兽医》2007,47(12):3965-3975
In order to identify the molecular markers related to alive litter size of Bama Xiang pigs,the genome-wide association study (GWAS) was used to map and screen the candidate genes affecting the alive litter size trait.Ear tissue samples of 297 Bama Xiang pigs with multiple parity records were collected,and DNA was extracted and genotyped by porcine 50K SNP beadchip.After quality control and genotype imputation,the alive litter size of Bama Xiang pigs were GWAS by Tassel.The results showed that the average number born alive per litter of Bama Xiang pigs increased gradually with the increasing of parity in the range of 1-9 parities.A total of 32 816 SNPs were obtained after quality control and filtration.8 SNPs related to alive litter size of Bama Xiang pigs were screened by genome-wide association analysis,which were significant at genome or chromosome level.Based on the enrichment analysis of the coding genes in the region between 500 kb upstream and downstream of the associated significant SNP loci,and the QTL regions and gene functions related to porcine reproductive traits,4 genes (CAPZB,MSH3,CITED2 and HSD17B7) were finally identified to be candidate genes related to alive litter size of Bama Xiang pigs. 相似文献
1000.
1株高致病性血凝性脑脊髓炎病毒的分离与鉴定 总被引:1,自引:1,他引:1
利用细胞培养方法从临床表现神经症状的死亡仔猪脑组织内分离获得1株病毒,同时对该病毒进行电镜负染观察、昆明种小鼠致病性试验、RT-PCR检测和部分基因测序分析。电镜观察可见细胞培养物中有大量的直径约115 nm的冠状病毒样粒子;接种病毒的小鼠均出现典型的神经症状,死亡率100%;血凝性脑脊髓炎病毒(HEV)特异性引物RT-PCR扩增结果阳性;其S基因序列与GenBank中登录的HEV-67 N相应基因序列的同源性高达99.6%。结果表明,分离的病毒为猪血凝性脑脊髓炎病毒,分离株暂命名为HEV-CC-2007。 相似文献