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71.
Monika Sobczuk-Szul Magdalena Mochol Zenon Nogalski Paulina Pogorzelska-Przybyłek 《Animal Science Journal》2021,92(1):e13516
This study was designed to compare the fatty acid profiles of four types of fat depots from bulls, steers, and heifers. All animals were Polish Holstein-Friesian and Limousin crossbreds fattened semi-intensively—silage at libitum and concentrate in the amount corresponding to 30% of their net energy requirements. The fatty acid profile in intramuscular, intermuscular, and external and internal fat was determined. The intramuscular fat of bulls was most abundant in total PUFAs and n-6 PUFAs, and functional fatty acids C 18:2, C 20:4, and C 22:5 in comparison with steers and heifers. Regardless of sex category, intramuscular and external fat were characterized by higher levels of UFAs and a more desirable MUFA/SFA ratio than the remaining fat types. It should also be noted that external fat was more abundant in CLA than other fat types, and that the highest CLA content was found in bull fat, compared with the remaining sex categories of cattle. 相似文献
72.
Hiroto Miura Takuya Hashimoto Yukiko Kawanishi Hiroki Kawauchi Ryo Inoue Noriaki Shoji Kunihiko Saito Mario Sekiya Yosuke Saito Jumpei Yasuda Chiemi Yonezawa Tetsushiro Endo Hirotaka Kasuya Yutaka Suzuki Yasuo Kobayashi Satoshi Koike 《Animal Science Journal》2021,92(1):e13601
The rumen microbiota comprises a vast range of bacterial taxa, which may affect the production of high-quality meat in Japanese Black cattle. The aim of this study was to identify core rumen microbiota in rumen fluid samples collected from 74 Japanese Black cattle raised under different dietary conditions using 16S rRNA gene amplicon sequencing. In the rumen of fattening Japanese Black cattle, 10 bacterial taxa, showing >1% average relative abundance and >95% prevalence, irrespective of the dietary conditions and the fattening periods, were identified as the core rumen bacterial taxa, which accounted for approximately 80% of the rumen microbiota in Japanese Black cattle. Additionally, population dynamics of the core rumen bacterial taxa revealed two distinct patterns: Prevotella spp. and unclassified Bacteroidales decreased in the mid-fattening period, whereas unclassified Clostridiales, unclassified Ruminococcaceae, Ruminococcus spp., and unclassified Christensenellaceae increased during the same period. Therefore, the present study reports the wide distribution of the core rumen bacterial taxa in Japanese Black cattle, and the complementary nature of the population dynamics of these core taxa, which may ensure stable rumen fermentation during the fattening period. 相似文献
73.
74.
奶牛围产期的饲养管理是规模化奶牛场生产环节中的重中之重,该项工作不仅影响奶牛泌乳量和生鲜乳品质,还直接决定新生犊牛的健康水平和奶牛的产后恢复情况。因此,各牧场需要加强奶牛围产期的饲养管理,让奶牛在分娩前后平稳过渡。本文从营养需要、分群、饲养和环境等方面介绍了奶牛围产前期和围产后期的管理需要,以期为围产期奶牛的科学饲养管理提供理论参考。 相似文献
75.
本研究旨在探索延边黄牛肌球蛋白重链3(MYH3)和肌球蛋白重链8(MYH8)基因多态性及其与生长性状的关联性,应用DNA直接测序法和高分辨率熔解曲线分型技术对120头24月龄延边黄牛MYH3、MYH8基因的遗传变异进行分析,并结合延边黄牛生长性状数据进行了关联分析。结果显示,在MYH3基因的29602748位点检测到一处T>G突变,包含2个等位基因:T和G,存在3种基因型:TG、TT和GG;在MYH8基因的29406042位点检测到一处C>T突变,包含2个等位基因:C和T,存在3种基因型:CT、CC和TT。关联分析显示,MYH3基因29602748位点T>G突变显著影响24月龄延边黄牛十字部高和腰角宽,表现为GG基因型十字部高显著高于TT基因型(P<0.05),腰角宽显著高于TT和TG基因型(P<0.05)。MYH8基因29406042位点C>T突变显著影响24月龄延边黄牛体重和胸围,表现为CT和TT基因型体重显著高于CC基因型(P<0.05);TT基因型胸围显著高于CC基因型(P<0.05)。本研究结果表明,MYH3、MYH8基因多态性与延边黄牛的部分生长性状相关,可作为现代肉牛育种中分子标记辅助选择的候选基因。 相似文献
76.
王承超 《畜牧兽医科学(电子版)》2021,(4):76-77
牛羊都是反刍动物,它们拥有4个胃,分别是瘤胃、网胃、瓣胃和真胃。前3个胃统称为前胃,在前胃中有大量的可以分解和消化饲料中粗纤维的细菌,是牛羊以粗饲料作为主要食物的原因之一。很多牛羊非常容易出现前胃疾病,饲养人员要掌握牛羊前胃疾病的预防办法和治疗措施。 相似文献
77.
78.
Utilization of digital differential display to identify differentially expressed genes related to rumen development 下载免费PDF全文
Daichi Kato Yutaka Suzuki Satoshi Haga KyoungHa So Eri Yamauchi Miwa Nakano Hiroshi Ishizaki Kichoon Choi Kazuo Katoh Sang‐Gun Roh 《Animal Science Journal》2016,87(4):584-590
This study aimed to identify the genes associated with the development of the rumen epithelium by screening for candidate genes by digital differential display (DDD) in silico. Using DDD in NCBI's UniGene database, expressed sequence tag (EST)‐based gene expression profiles were analyzed in rumen, reticulum, omasum, abomasum and other tissues in cattle. One hundred and ten candidate genes with high expression in the rumen were derived from a library of all tissues. The expression levels of 11 genes in all candidate genes were analyzed in the rumen, reticulum, omasum and abomasum of nine Japanese Black male calves (5‐week‐old pre‐weaning: n = 3; 15‐week‐old weaned calves: n = 6). Among the 11 genes, only 3‐hydroxy‐3‐methylglutaryl‐CoA synthase 2 (HMGCS2), aldo‐keto reductase family 1, member C1‐like (AKR1C1), and fatty acid binding protein 3 (FABP3) showed significant changes in the levels of gene expression in the rumen between the pre‐ and post‐weaning of calves. These results indicate that DDD analysis in silico can be useful for screening candidate genes related to rumen development, and that the changes in expression levels of three genes in the rumen may have been caused by weaning, aging or both. © 2015 Japanese Society of Animal Science 相似文献
79.
Accuracy of imputation of single nucleotide polymorphism marker genotypes from low‐density panels in Japanese Black cattle 下载免费PDF全文
Shinichiro Ogawa Hirokazu Matsuda Yukio Taniguchi Toshio Watanabe Akiko Takasuga Yoshikazu Sugimoto Hiroaki Iwaisaki 《Animal Science Journal》2016,87(1):3-12
Using target and reference fattened steer populations, the performance of genotype imputation using lower‐density marker panels in Japanese Black cattle was evaluated. Population imputation was performed using BEAGLE software. Genotype information for approximately 40 000 single nucleotide polymorphism (SNP) markers by Illumina BovineSNP50 BeadChip was available, and imputation accuracy was assessed based on the average concordance rates of the genotypes, varying equally spaced SNP densities, and the number of individuals in the reference population. Two additional statistics were also calculated as indicators of imputation performance. The concordance rates tended to be lower for SNPs with greater minor allele frequencies, or those located near the ends of the chromosomes. Longer autosomes yielded greater imputation accuracies than shorter ones. When SNPs were selected based on linkage disequilibrium information, relative imputation accuracy was slightly improved. When 3000 and 10 000 equally spaced SNPs were used, the imputation accuracies were greater than 90% and approximately 97%, respectively. These results indicate that combining genotyping using a lower‐density SNP chip with genotype imputation based on a population of individuals genotyped using a higher‐density SNP chip is a cost‐effective and valid approach for genomic prediction. 相似文献