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41.
Polyphenols in Eucalyptus leaves improved the egg and meat qualities and protected against ethanol‐induced oxidative damage in laying hens 下载免费PDF全文
W. Li J. Miao N. Chen X. Shao Y. Cao 《Journal of animal physiology and animal nutrition》2018,102(1):214-223
Polyphenols in Eucalyptus leaves (PE) were value resources due to various pharmacological activities, but data on the effect on laying hens are very scare. This study was conducted to determine the effect of PE on the laying performance, egg traits, meat quality, antioxidant status and liver tissues of laying hens. One hundred and twenty 256‐day‐old Yueqinhuang laying hens were randomly assigned to four treatment groups (different levels of PE at 0, 0.5, 0.8 and 1.2 g/kg diet) for 63 days with 15 replicates per group. Addition of 0.8 g/kg PE not only improved the egg trait by increasing the eggshell thickness and decreasing MDA production and cholesterol content in the egg yolk, but also significantly enhanced meat quality of hens, as suggested by the increase pH45 min (p < .01) and a* value, and decrease drip loss rate (p < .01). Meanwhile, under acute ethanol‐induced oxidative damage condition, supplementation of 0.8 g/kg PE enhanced the serum antioxidant status by increasing enzymatic activities (GSH‐PX, T‐SOD, T‐AOC), inhibited oxidative damage and provided protective effect to liver tissue. In conclusion, addition of 0.8 g/kg PE not only improved the egg traits and meat quality without obvious adverse effects, but also increased the serum antioxidant status of the hens and protected their liver tissue from ethanol‐induced oxidative damage. This study indicated that PE could be utilized as an effective feed additive for laying hens to improve health performance and egg traits. 相似文献
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Multimarker and rare variants genomewide association studies for bone weight in Simmental cattle 下载免费PDF全文
J. Miao X. Wang J. Bao S. Jin T. Chang J. Xia L. Yang B. Zhu L. Xu L. Zhang X. Gao Y. Chen J. Li H. Gao 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2018,135(3):159-169
Bone weight, defined as the total weight of the bones in all the forequarter and hindquarter joints, can reflect somebody conformation traits and skeletal diseases. To gain a better understanding of the genetic determinants of bone weight, we used a composite strategy including multimarker and rare‐marker association to perform genomewide association studies (GWAS) for that character in Simmental cattle. Our strategy consisted of three models: (i) A traditional linear mixed model (LMM) was applied (Q+K‐LMM); (ii) single nucleotide polymorphisms (SNPs) with p‐values less than .05 from the LMM were selected to undergo the least absolute shrinkage and selector operator (Lasso) in the second stage (LMM‐Lasso); (iii) genes containing two or more rare SNPs were examined by performing the sequence kernel association test (gene‐based SKAT). A total of 1,225 cattle were genotyped with an Illumina BovineHD BeadChip containing 770,000 SNPs. After the quality‐control procedures, 1,217 individuals with 608,696 common SNPs and 105,787 rare SNPs (with 0.001 < minor allele frequency [MAF] <0.05) remained in the sample for analysis. A traditional LMM successfully mapped three genes associated with bone weight, while LMM‐Lasso identified nine genes, which included all genes found by traditional LMM. Only a single gene, EPHB3, surpassed the significance threshold after Bonferroni correction in gene‐based SKAT. In conclusion, based on functional annotation and results from previous endeavours, we believe that LCORL, RIMS2, LAP3, PRKAR2B, CHSY1, MAP2K6 and EPHB3 are candidate genes for bone weight. In general, such a comprehensive strategy for GWAS may be useful for researchers seeking to probe the full genetic architecture underlying economic traits in livestock. 相似文献
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利用聚乙二醇(PEG)试剂室内模拟不同干旱(0、-0.10、-0.20、-0.40、-0.80、-1.60 MPa)和温度(10、15、20、25、30℃)环境条件,对西藏班戈县野生型赖草(Leymus secalinus)种子萌发特性进行研究。结果表明,赖草种子在恒温10~30℃和变温10~30℃均能萌发.恒温25℃处理下,种子萌发达到了最佳响应;恒温15℃和变温20/30℃处理对赖草种子发芽率具有显著影响(P0.05),而恒温10和30℃对赖草种子发芽率具有极显著影响(P0.05);随着PEG渗透势的增加,赖草种子发芽率、发芽指数、活力指数和胚芽长均出现了不同程度的下降现象,而胚根则表现为先升后降的变化现象。25℃和蒸馏水处理下,野生赖草种子萌发效果最佳;而在25℃和-0.10~0 MPa渗透势处理下,赖草种子胚根优于胚芽生长。 相似文献
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MAO Ran LI Qing-quan SHI Yan LAN Xiang-li WANG Min ZONG Ze-jun XIA Guo-zhong HAN Tian-long 《中国畜牧兽医》2015,42(12):3308-3314
In order to explore the effect of different L-lysine levels added in semen dilution on the fresh Dorper sheep quality stored at liquid state,3 health Dorper ram were used to collect semen which were equal-packaged and added to solution containing different levels (0,0.1,0.2,0.3,0.4 and 0.5 g) L-lysine in 120 mL diluent and at 0,6,24,30,48,54,72 and 78 h,the sperm motility,membrane integrity and acrosome integrity were detected.The results showed that the sperm motility in groups added 0,0.1 and 0.2 g L-lysine were higher than other groups,and that in 0.4 and 0.5 g L-lysine groups decreased faster than other groups;The sperm motility in 0.5 g L-lysine group reduced to 0 at 30 h,and it reduced to 0 at 48 h in the group added 0.4 g L-lysine;The effective survival time and survival index in the group added 0.1 g L-lysine was higher than other groups (P< 0.05);The membrane integrity of 0.1 g group was the highest,that had no significant difference with control group from 0 to 54 h (P >0.05),while after 72 h the two groups had significant differences (P< 0.05).The membrane integrity in 0.4 and 0.5 g groups were the worst,and that was significant different with other groups (P< 0.05);The acrosome integrity of 0.1 g group was the highest which had no significant difference with control group (P >0.05),0.4 and 0.5 g groups were the worst,the difference between them was not significant (P >0.05),while was extremely significant difference with other groups except for 0 and 6 h (P< 0.01).The results suggested that dilution added a high concentration of L-lysine could inhibit sperm quality,when the count of L-lysine was more than 0.2 g,sperm quality was significantly decreased,adding 0.1 g L-lysine could improve Dorper sheep fresh sperm quality stored at liquid state. 相似文献
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适度卷曲有利于提高水稻叶片的光合效率,增加植株光合产物的有效积累量。我们利用甲基磺酸乙酯(EMS)处理籼型水稻保持系西农1B,获得一个稳定遗传的水稻半外卷叶突变体。该突变体从十叶期开始各叶片逐渐向外卷曲直至半卷状,并伴随茎秆半矮化和叶片披垂,暂被命名为semi-outcurved leaf 1(sol1)。与野生型(WT)相比,sol1的叶片卷曲指数均达到30%以上(P<0.01);倒一、倒二、倒三、倒四节节间长度和穗长极显著缩短,倒一、倒二、倒三叶的叶夹角显著或极显著增加;有效穗数、千粒重、每穗实粒数、结实率显著或极显著下降,一次枝梗数则增加11.3%(P<0.05)。sol1的蒸腾速率、胞间CO2浓度、气孔导度显著高于野生型。石蜡切片显示,sol1倒一叶的泡状细胞体积变小,数量显著增多,表皮细胞体积略微增大。遗传分析表明,sol1的半外卷叶性状受1对隐性核基因调控,定位于6号染色体标记JY6-3和JY6-10之间165 kb的物理范围内,共含15个注释基因。qRT-PCR结果表明,与泡状细胞相关的内卷基因和外卷叶基因RL14、Roc5、REL1在突变体sol1中呈不同程度的上调,NRL、BRD1、OsHox32、ADL1、LC2则呈不同程度的下调。研究结果为SOL1基因的克隆和功能研究奠定了基础。 相似文献
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