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Milk Production of Sarda Suckler Cows with Different Calving Period
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作者 Marco Acciaro Corrado Dimauro +6 位作者 Valeria Giovanetti Giampaolo Epifani Carla Manca Salvatore Contini Andrea Cabiddu Mauro Decandia Giovanni Molle 《Journal of Agricultural Science and Technology(A)》 2020年第2期86-97,共12页
The study explored the relationship between the performance of calves and calving season in a Mediterranean rangeland-based beef livestock system.Twenty multiparous Sarda cows,grazing on a natural pasture,with two dis... The study explored the relationship between the performance of calves and calving season in a Mediterranean rangeland-based beef livestock system.Twenty multiparous Sarda cows,grazing on a natural pasture,with two distinct calving periods(group A,11 animals,calving date 15/10/2016±16(means±s.d.),and group W,nine animals,calving date 26/01/2017±11)were used.Meteorological data,herbage quality,daily milk yield(DMY),total milk yield(TMY),body weight(BW)of cows and calf,body-weight daily gain(ADG)of calves,body condition score(BCS)and calving interval(CI)of cows were assessed.A mixed-effects model was used to DMY and ADG data while TMY,BCS,weaning weight(WW)and CI data were analyzed by a linear model.The most determining factors in the DMY and ADG were detected by means of partial least square regression(PLSR)procedure.Group W showed higher DMY(6.5±0.3 kg/d vs.4.5±0.3 kg/d,p<0.001)and TMY(1,189±70 kg vs.830±60 kg,p=0.002)than Group A,but this did not result in a greater ADG of calves(Group A:0.83±0.04 kg/d/animal and Group W:0.99±0.09 kg/d/animal,p-value not significant)or WW when adjusted for their age(Group A:216±14 kg/animal and Group W:250±22 kg/animal,p-value not significant).In contrast,the WW actually measured were higher in Group A than in Group W(257±7 kg vs.175±8 kg,p<0.001).The Group W cows experienced a minor CI than Group A cows(288±13 d vs.320±8 d,p=0.04).The results of PLSR suggest that the factors with utmost importance for both DMY and ADG were the age and the body-weight of cows,highlighting the excellent maternal ability of Sarda breed and its good adaptation to environment. 展开更多
关键词 sarda cow suckler-cow system weigh-suckle-weigh method partial least square regression
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平鲷精子的超显微结构 被引量:15
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作者 刘雪珠 杨万喜 《东海海洋》 2004年第1期43-48,共6页
对平鲷精子的超显微结构进行了研究,结果表明:平鲷精子由头部、中段和尾部(鞭毛)三部分组成。头部的细胞核呈近圆形,染色质致密,内有核空泡,有的核空泡内部有电子致密物质存在。中段紧连于核的后端,由中心粒复合体和袖套组成,中心粒复... 对平鲷精子的超显微结构进行了研究,结果表明:平鲷精子由头部、中段和尾部(鞭毛)三部分组成。头部的细胞核呈近圆形,染色质致密,内有核空泡,有的核空泡内部有电子致密物质存在。中段紧连于核的后端,由中心粒复合体和袖套组成,中心粒复合体结构独特,由近端中心粒、中心粒间体和基体组成,中心粒间体位于近端中心粒和基体之间,部分精子近端中心粒中央腔中尚有一个粗大的颗粒状结构;袖套接于核的后端,其中有线粒体和囊泡。尾部由袖套腔中伸出,其中心结构是轴丝,外方有侧鳍。 展开更多
关键词 平鲷 精子 超显微结构 中心粒复合体 袖套 硬骨鱼
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3种鲣鱼背部肌肉的营养成分分析及评价 被引量:29
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作者 童铃 金毅 +1 位作者 徐坤华 戴志远 《南方水产科学》 CAS CSCD 北大核心 2014年第5期51-59,共9页
分析与评价了鲣(Katsuwonus pelamis)、东方狐鲣(Sarda orientalis)和扁舵鲣(Auxis thazard)3种鲣鱼背部肌肉的营养成分。结果显示:1)3种鲣鱼的粗蛋白质量分数为22.86%~24.65%,粗脂肪质量分数为1.41%~2.51%,3种鲣鱼均含有丰... 分析与评价了鲣(Katsuwonus pelamis)、东方狐鲣(Sarda orientalis)和扁舵鲣(Auxis thazard)3种鲣鱼背部肌肉的营养成分。结果显示:1)3种鲣鱼的粗蛋白质量分数为22.86%~24.65%,粗脂肪质量分数为1.41%~2.51%,3种鲣鱼均含有丰富的常量和微量元素;2)鲣和东方狐鲣背部肌肉均检出17种脂肪酸,而扁舵鲣检出23种,其∑PUFA/∑SFA分别为1.17、0.93和1.14,n-6/n-3系∑PUFA值分别为0.07、0.04和0.11,此外,鲣背部肌肉的多不饱和脂肪酸相对质量分数为38.98%,高于东方狐鲣的33.64%和扁舵鲣的37.93%;3)东方狐鲣背部肌肉的必需氨基酸质量分数和必需氨基酸指数(EAAI)分别为35.10%和0.90,略高于鲣的33.95%和0.89与扁舵鲣的32.51%和0.89。 展开更多
关键词 东方狐鲣 扁舵鲣 营养成分 营养评价
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Evolution of personality and locomotory performance traits during a late Pleistocene island colonization in a tree frog
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作者 Roberta Bisconti Claudio Carere +3 位作者 David Costantini Anita Liparoto Andrea Chiocchio Daniele Canestrelli 《Current Zoology》 SCIE CAS CSCD 2023年第5期631-641,共11页
Recent empirical and theoretical studies suggest that personality and locomotory performance traits linked to dispersal abilities are crucial components of the dispersal syndromes,and that they can evolve during range... Recent empirical and theoretical studies suggest that personality and locomotory performance traits linked to dispersal abilities are crucial components of the dispersal syndromes,and that they can evolve during range expansions and colonization processes.Island colonization is one of the best characterized processes in dispersal biogeography,and its implication in the evolution of phenotypic traits has been investigated over a wide range of temporal scales.However,the effect of island colonization on personality and performance traits of natural populations,and how these traits could drive island colonization,has been little explored.Noteworthy,no studies have addressed these processes in the context of late Pleistocene range expansions.Here,we investigated the contribution of island colonization triggered by postglacial range expansions to intraspecific variation in personality and locomotory performance traits.We compared boldness,exploration,jumping performance,and stickiness abilities in populations from 3 equidistant areas of the Tyrrhenian tree frog Hyla sarda,2 from the main island(Corsica Island),and 1 from the recently colonized island of Elba.Individuals from Elba were significantly bolder than individuals from Corsica,as they emerged sooner from a shelter(P=0.028),while individuals from Corsica showed markedly higher jumping and stickiness performance(both P<0.001),resulting as more performing than those of Elba.We discuss these results in the context of the major microevolutionary processes at play during range expansion,including selection,spatial sorting,founder effects,and their possible interaction with local adaptation processes. 展开更多
关键词 behavioral syndrome COLONIZATION dispersal founder effect Hyla sarda INSULARITY PERSONALITY
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