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51.
We evaluated the influence on milk production of feeding early lactation cows a diet that included 14.5% crude protein (CP) and that did not meet methionine (Met) requirements or that met them by supplying rumen‐protected Met (RPMet). Thirty‐nine multiparous Holstein cows were allocated into two groups. For 15 weeks after calving, each group was fed one of the two total mixed rations, Control (= 20) or Treatment (= 19). The Treatment group received added RPMet at 0.034% (8 g/day) of the Control diet on dry matter basis. The adequacies of Met for the Control and Treatment groups were 96% and 106%, respectively, and for other amino acids, >110%. The CP level (14.5%) was 1 percentage point lower than that recommended by the Japanese Feeding Standard (2006). No between‐group differences were found in milk yield (40 kg/day), milk composition, plasma profile, rumen fermentation, nitrogen balance, or cow health. Met intake and the amount of rumen‐undegradable feed Met were higher in the Treatment group (< 0.05). Microbial Met and total metabolizable Met did not differ between groups. Supplying RPMet in a 14.5% CP diet during early lactation did not dramatically affect milk production, because the amount of total metabolizable Met was unchanged.  相似文献   
52.
Kazakhstan is the largest landlocked country and contains two important propagation routes for livestock from the Fertile Crescent to Asia. Therefore, genetic information about Kazakhstani cattle can be important for understanding the propagation history and the genetic admixture in Central Asian cattle. In the present study, we analyzed the complete mtDNA D‐loop sequence and SRY gene polymorphism in 122 Kazakhstani native cattle. The D‐loop sequences revealed 79 mitochondrial haplotypes, with the major haplogroups T and I. The Bos taurus subhaplogroups consisted of T (3.3%), T1 (2.5%), T2 (2.5%), and T4 (0.8%) in addition to the predominant subhaplogroup T3 (86.9%), and the Bos indicus subhaplogroup of I1 (4.1%). Subsequently, we investigated the paternal lineages of Bos taurus and Bos indicus, however, all Kazakhstani cattle were shown to have Y chromosome of Bos taurus origin. While highly divergent mtDNA subhaplogroups in Kazakhstani cattle could be due to the geographical proximity of Kazakhstan with the domestication center of the Fertile Crescent, the absence of Bos indicus Y chromosomes could be explained by a decoupling of the introgression dynamics of maternal and paternal lineages. This genetic information would contribute to understanding the genetic diversity and propagation history of cattle in Central Asia.  相似文献   
53.
Goats (Capra hircus) were domesticated in the Fertile Crescent and propagated all over the world. The Silk Road through the Eurasian Steppe belt is a possible propagation route for domestic goats to Central Asia. Kazakhstan is in close geographical proximity to domestication centers and covers the majority of the Eurasian Steppe belt. In this study, we examined the genetic diversity and phylogeographic structure of Kazakhstani goats. The mtDNA sequences of 141 Kazakhstani goats were categorized into haplogroups A, C, and D, of which haplogroup A was predominant (97%), whereas haplogroups C and D were detected at low frequencies (1.4% each). The Kazakhstani haplotypes C were thzen categorized into Asian mtDNA type. Sequence analysis of the SRY gene on the Y‐chromosome in 67 male Kazakhstani goats revealed two haplotypes: Y1A (64%) and Y2A (36%). Analysis of the distribution of mtDNA haplogroups and SRY haplotypes from Eurasia and Africa demonstrated genetic similarity among animals from Kazakhstan, Mongolia, and Northwest China located on the Eurasian Steppe belt. These phylogeographic results suggested that the Eurasian Steppe belt was an important propagation route for goats to Central Asia.  相似文献   
54.
Single nucleotide polymorphism (SNP) arrays are widely used for genetic and genomic analyses in cattle breeding; thus, data derived from SNP arrays have accumulated on a large scale nationwide. Commercial SNP arrays contain a considerable number of unassigned SNPs on the chromosome/position on the genome; these SNPs are excluded in subsequent analyses. Notably, the position‐unassigned SNPs, or “buried SNPs” include some of the markers associated with genetic disease. In this study, we identified the position of buried SNPs using the Basic Local Alignment Search Tool against the surrounding sequences and characterized the relationship between SNPs and genetic diseases in Online Mendelian Inheritance in Animals based on the genomic position. We determined the position of 285 buried SNPs on the genome and surveyed the genotype and allele frequencies of these SNPs in 5,955 individual Japanese Black cattle. Eleven SNPs associated with genetic disease, which contained five buried SNPs, were found in the population with the risk allele frequency ranging from 0.00008396 to 0.46. These results indicate that buried SNPs in the bovine SNP array can be utilized to identify associations with genetic disorders from large scale accumulated SNP genotype data in Japanese Black cattle.  相似文献   
55.
In order to refine the national estimate of methane emission from stored cattle slurry, it is important to comprehend the basic characteristics of methane production. Two dairy cattle slurries were obtained from livestock farms located in Hokkaido (a northern island) and Kyushu (a southern island). The slurries were diluted with water into three levels: undiluted, three times diluted, and 10 times diluted. Three hundred mL of the slurries were put into a bottle with a headspace volume of 2.0 L, which was filled with nitrogen gas and then sealed by butyl rubber. Four levels of temperature were used for incubation: 35, 25, 15 and 5 °C. The time course of the cumulative methane production per volatile solid (VS) was satisfactorily expressed by an asymptotic regression model. The effect of dilution on the methane production per VS was not distinctive, but that of temperature was of primary importance. In particular, higher temperature yields a higher potential production and a shorter time when the cumulative production reaches half of the potential production. The inclusive and simple models obtained in this study indicate that the cumulative methane production from stored cattle slurry can be explained by VS, temperature and length of storage.  相似文献   
56.
57.
Fatty acid composition is an important indicator of beef quality. The objective of this study was to search the potential candidate region for fatty acid composition. We performed pool‐based genome‐wide association studies (GWAS) for oleic acid percentage (C18:1) in a Japanese Black cattle population from the Hyogo prefecture. GWAS analysis revealed two novel candidate regions on BTA9 and BTA14. The most significant single nucleotide polymorphisms (SNPs) in each region were genotyped in a population (n = 899) to verify their effect on C18:1. Statistical analysis revealed that both SNPs were significantly associated with C18:1 (p = .0080 and .0003), validating the quantitative trait loci (QTLs) detected in GWAS. We subsequently selected VNN1 and LYPLA1 genes as candidate genes from each region on BTA9 and BTA14, respectively. We sequenced full‐length coding sequence (CDS) of these genes in eight individuals and identified a nonsynonymous SNP T66M on VNN1 gene as a putative candidate polymorphism. The polymorphism was also significantly associated with C18:1, but the p value (p = .0162) was higher than the most significant SNP on BTA9, suggesting that it would not be responsible for the QTL. Although further investigation will be needed to determine the responsible gene and polymorphism, our findings would contribute to development of selective markers for fatty acid composition in the Japanese Black cattle of Hyogo.  相似文献   
58.
Shinji  Junpei  Nohara  Setsuo  Yagi  Nobuyuki  Wilder  Marcy 《Fisheries Science》2020,86(3):601-601
Fisheries Science - The article "Bio-economic analysis of super-intensive closed shrimp farming and improvement of management plans: a case study in Japan", written by Junpei Shinji,...  相似文献   
59.
Of all plant materials used to cover the roofs of traditional Japanese buildings, Japanese cypress (Chamaecyparis obtusa) bark, hiwada, has the longest service life and has been used from ancient times. However, wood and bark properties after hiwada harvest have not been evaluated in detail. We studied whether decortication for hiwada production in winter affected xylem and phloem formation. Decorticated trees still preserved all inner bark and part of the outer bark, and both decorticated and control trees had similar annual ring structures at all stem heights in the xylem and phloem. In both xylem and inner bark, no significant difference in ring width at any stem height was found between annual rings before and after decortication. Thus, this study revealed that the decortication of bark for hiwada production does not affect the formation of xylem and the inner and outer bark if decortication is carried out by highly skilled workers in winter.  相似文献   
60.
杨树不同无性系叶面积模型的选择及其建立   总被引:4,自引:1,他引:4  
刘建伟 Blake  TJ 《林业科学》1994,30(6):481-486
应用Li-3000A叶面积仪测定了8个无性系的叶型及叶面积指标,选择了8个模型,以叶片主脉长(L)和最大宽(W),以及两者乘积(L×W)为三个变量作与叶面积的相关关系分析,筛选出复相关系数均达0.95以上的最佳模型为:(1)与两者乘积的叶面积模型:lgY=a+bx+b+clgx,(2)与最大宽度的模型:Y=a+bx+cx2。但与叶片主脉长模拟效果较差。此外,还得出了杨树无性系的叶面积通用模型,即:Y=—0.450826十0.00071X+0.976335lgx(x为L×W),和Y=—1.697387十0.733497x—0.001253x2(x为W)。上述8个无性系及杨树通用的模型的建立为叶面积的计算、预测等生理生态研究提供了科学依据,使得叶面积测定更加省时、可靠和方便。  相似文献   
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