The Correlative Analysis between Body Size and Slaughter Traits in Wei-ning Chickens     

JIANG Hui-mei  ZHANG Yi-ling  LIU Zhang-zhong  YANG Yuan-qing  SHU Chang  LI Wan-gui  ZHANG Yi-yu  LIU Ruo-yu 《中国畜牧兽医》2015,42(12):3300-3307

It aimed to investigate the sex differences and correlation of body size and slaughter traits in Wei-ning chicken,the research measured the body size and slaughter traits of 65 Wei-ning chicken(♀:33;♂:32 ) at the age of 180 days according to the nation livestock body size and slaughter measurement standards,and analysis on the correlative between body size and slaughter traits.The results showed that the lean body length was significant difference in the different sex chicken groups (P< 0.05 ),and the cocks were higher than hens,the comb hight and keel bone length of cocks were extremely significant higher than hens (P< 0.01 ).All of the body size and slaughter trait showed difference between cocks and hens,moreover,the Wei-ning chicken also showed excellent appearance,hold the strong body constitution character,good meat performance and adaptability for other native chickens,the body constitution and meat performance of cocks were better than hens.Besides,the different body size,most of slaughter traits and between body size and slaughter traits were positively correlaton,and most of indexes showed the significant or extremely significant correlation levels (P< 0.05;P< 0.01),these data would be crucial insight for the breeding,especial early breeding of Wei-ning chicken.  相似文献   

乌湖杂交羊GnRHR与INHA基因多态性及其互作效应对产羔数的影响     

刘海霞  韩大勇  朱爱文  闫伟  王步忠  蔡子健 《中国畜牧兽医》2020,47(3):780-788

试验旨在探究GnRHR和INHA基因遗传变异及其互作效应对绵羊产羔数的影响。参考GenBank发布的绵羊GnRHR基因（登录号：AH004943）和牛INHA基因（登录号：U16237）的DNA序列设计引物，采用PCR-SSCP技术检测GnRHR和INHA基因在乌湖羊、湖羊、乌骨绵羊中的遗传多态性，分析多态位点与产羔数的相关性，以及GnRHR和INHA基因间互作效应。结果显示，乌湖羊和湖羊群体GnRHR和INHA基因均存在多态位点，分别检测到GG、GC、CC和AA、AB、BB基因型，乌骨绵羊因样本较少，未发现多态位点。测序发现，GnRHR基因编码区198 bp处发生G→C突变，导致甘氨酸变为精氨酸，为错义突变；INHA基因877 bp处发生T→C突变，为同义突变（仍为天冬氨酸）。遗传学分析显示，GG和AA为优势基因型，G和A为优势等位基因；χ²适合性检验显示，试验羊群体GnRHR和INHA基因型分布处于Hardy-Weinberg平衡（P>0.05）；分析GnRHR与INHA基因互作效应发现，基因互作效应在乌湖羊和湖羊群体差异显著（P<0.05），ABCC互作基因型互作效应最大，AAGG互作基因型互作效应最小。乌湖羊ABCC互作基因型的平均产羔数比AAGG互作基因型多1.68只，湖羊ABCC互作基因型产羔数比AAGG互作基因型多1.32只，ABCC互作基因型比AB和CC基因型的产羔数都高，表明互作效应与羊产羔数呈正相关。本研究认为，INHA基因T877C位点与GnRHR基因G198C位点互作基因型与绵羊产羔数紧密关联，对试验羊群体产羔数影响显著。  相似文献   

饲料亚麻酸含量对大规格鲈鱼生长性能、抗氧化指标和血清生化指标的影响   总被引：1，自引：0，他引：1  

王成强  徐后国  梁萌青  郑珂珂  柳茜 《动物营养学报》2016,(10):3123-3133

本试验旨在探讨饲料亚麻酸(ALA)含量对大规格鲈鱼生长性能、抗氧化指标和血清生化指标的影响,以确定大规格鲈鱼饲料中ALA的适宜含量。通过在基础饲料中添加苏子油,制成ALA含量分别为饲料干重0.06%、0.99%、2.03%、3.18%、4.12%和5.08%的6种等氮等脂的试验饲料。将上述试验饲料投喂初始体重为(207.77±0.64)g的鲈鱼,每种饲料设3个重复,每个重复放养20尾鱼,养殖周期为12周。结果表明:1)特定生长率(SGR)和饲料效率(FE)随饲料ALA含量的升高均呈先升高后降低的趋势,且SGR和FE均在2.03%ALA组有最大值,同时2.03%与3.18%ALA组的SGR和FE差异不显著(P0.05);肝体指数(HSI)与脏体指数(VSI)均在5.08%ALA组达到最大值,且显著高于0.06%ALA组(P0.05);存活率(SR)和肥满度(CF)在各组之间无显著差异(P0.05)。2)随着饲料中ALA含量的升高,鱼体粗蛋白质含量表现为逐渐下降的趋势,粗脂肪含量呈现增加趋势,4.12%和5.08%ALA组鱼体粗蛋白质含量显著低于0.06%ALA组(P0.05),而4.12%和5.08%ALA组鱼体粗脂肪含量则显著高于0.06%、0.99%、2.03%、3.18%ALA组(P0.05);不同组之间鱼体的水分与粗灰分含量无显著差异(P0.05)。3)2.03%ALA组血清和肝脏中超氧化物歧化酶(SOD)活性与3.18%ALA组无显著差异(P0.05),但显著高于0.06%与5.08%ALA组(P0.05)。2.03%、3.18%ALA组血清中丙二醛(MDA)含量显著低于0.06%和5.08%ALA组(P0.05);同时,肝脏中MDA含量在2.03%ALA组达到最低,除与3.18%ALA组无显著差异(P0.05)外,显著低于其他各组(P0.05)。4)血清中谷草转氨酶(GOT)和谷丙转氨酶(GPT)活性均在2.03%ALA组最低,且显著低于0.06%与5.08%ALA组(P0.05);血清中甘油三酯(TG)和胆固醇(CHOL)含量在4.12%ALA组有最大值,且显著高于0.06%ALA组(P0.05);随着饲料中ALA含量的升高,血清中高密度脂蛋白胆固醇(HDL-C)含量呈先升高后降低趋势,2.03%、3.18%、4.12%ALA组显著高于其他组(P0.05)。综上所述,饲料中适宜含量(2.03%~3.18%)的ALA能够促进大规格鲈鱼的生长,提高抗氧化能力与肝脏健康水平;以SGR与FE作为评价指标,经二次曲线回归分析得出体重为207.77~406.94 g的鲈鱼饲料中ALA的适宜含量分别为饲料干重的2.53%和2.72%。  相似文献   

Use of Plant Growth Regulators in Blueberry Production in the Southeastern U.S.     

《International Journal of Fruit Science》2013,13(3):41-54

Abstract

Blueberry (Vaccinium sp.) production has expanded rapidly in the Southeastern U.S. over the past two decades, and various production problems have been encountered. These problems include poor pollination, low fruit set, freeze damage, variable yields, and small fruit size among others. Plant growth regulators (PGRs) have been utilized to overcome some production problems with some degree of success. This paper reviews findings of research that has been conducted over the past few years with PGRs and blueberries in the Southeast.  相似文献   

紫玉洋葱鳞茎膨大及相关农艺性状观察     

常法平  张雪江  李书红  桑爱云  张光 《中国瓜菜》2013,26(5):32-33

为确定洋葱的最佳收获期,选用自选新品种紫玉洋葱作为观察材料,每间隔5d测量一次鳞茎球质量及相关农艺性状.结果表明,5月25日绿色功能叶片开始衰退,具有生活力根数6月4日达到最大值,6月10日单球质量达到最大值,表明该品种的最佳收获期为6月10日前后.  相似文献   

Egg size and its relationship with fecundity,newborn length and female size in Cuban poeciliid fishes (Teleostei: Cyprinodontiformes)     

José L. Ponce de León  Rodet Rodríguez  Martín Acosta  Mari C. Uribe 《Ecology of Freshwater Fish》2011,20(2):243-250

Abstract – This study describes the relationship between egg size (ES) and brood size (BS), newborn length (NL) and female total length (FTL) in ten species of Cuban poeciliids. Variability and the level of association among variables are analysed and comparisons of ES among species established. Egg size has the lowest variability among the analysed variables and in most species is not correlated with BS, when the effect of FTL is controlled. Cuban poeciliids, thought to be primarily lecithotrophic, can be separated in two groups according to ES, NL and BS relative to FTL. One such group inhabits mountain streams and produces large eggs and small broods. The other group is distributed in lowland wetlands and produces small eggs and large broods. In Cuban poeciliids, ES and NL are highly correlated, which suggests adaptive value for ES.  相似文献   

How reliable are results of pot experiments?     

《Communications in Soil Science and Plant Analysis》2012,43(9):895-902

Abstract

Results of pot experiments depend much on the environmental conditions under which they are conducted and on “personal factors”; such as the choice of the type of pots, rates of fertilisers applied, the way these fertilisers are applied, growing conditions in the glasshouse, and the decision when to terminate the experiment. The majority of pot experiments are conducted under environmental conditions which seldom or never occur in the field. We therefore cannot extrapolate their results to the field unless the experiments deal with growing factors which dominate all others.  相似文献   

Otolith size differences during early life of dwarf and cannibal Arctic char (Salvelinus alpinus)          下载免费PDF全文

Bjørn Florø‐Larsen  Anders G. Finstad  Ole K. Berg  Per H. Olsen 《Ecology of Freshwater Fish》2016,25(2):203-210

In Arctic and alpine lakes, Arctic char [Salvelinus alpinus (L.)] often form two distinct morphs: invertebrate feeders (‘dwarfs’) and piscivores (‘giant or cannibals’). Here, we test for early life history growth variation in dimorphic Arctic char as a proximate explanation for the observed life history variation between the two forms. Char were sampled in 11 alpine and Arctic Norwegian lakes. Dwarfs (defined as sexually mature char less than 15 cm long; N = 304) had a mean total length of 105 mm, whereas the typical cannibal (body length above 20 cm; N = 153) was 388 mm long. A positive correlation between egg size and otolith hatching ring were ascertained in a separate hatching experiment with brown trout (Salmo trutta) and it is assumed that this relationship also is valid for Arctic char, and otolith size was used as a proxy for length. Otolith hatching ring from Arctic char cannibals was larger (mean ± SD; 187 ± 24 μm) than those from dwarfs (mean ± SD; 164 ± 23 μm). There were only minor size differences between dwarfs and cannibals during the next three years, after which dwarfs usually matured. Two mutually nonexclusive, proximate explanations for the differentiation into separate morphs (dwarfs and cannibals) are therefore maternal effects and/or genetic based differentiation. The high catchability of large piscivorous char and low production in alpine and Arctic lake ecosystems may make these stocks particularly vulnerable to overexploitation.  相似文献   

浅谈美国大学“大班”教学的启示——美国UIUC营养与饲料学课程教学观摩有感     

王平 《家畜生态学报》2013,34(1):90-93

 与“以学生为中心”的教学理念一致，美国大学的课程教学呈现多样化的特点。论文分析了我国目前大学课程教学的现状后发现，为了给科研分配出足够的时间，教师投入教学的有效时间不能与不断上升的大学扩招规模保持同步增加。由此引发出在课堂规模扩大的情况下怎样保证课程教学质量的思考。结合在美国伊利诺伊大学香槟分校（UIUC）的访学经历，提出配套相应技术支撑体系、教学与人文结合以及采取课程组授课与“大班授课，小组讨论”等方式方法有助于提高“大班”课程授课的教学效果。  相似文献   

Competitive Strategies and Growth of Neighbouring Bromus valdivianus Phil. and Lolium perenne L. Plants Under Water Restriction     

I. F. López  P. D. Kemp  J. Dörner  C. A. Descalzi  O. A. Balocchi  S. García 《Journal of Agronomy and Crop Science》2013,199(6):449-459

Often perennial pastures have to tolerate soil water restriction during summer, which can affect the relative abundance of the most desired species. In the south of Chile, Bromus valdivianus and Lolium perenne are preferred species. The competitiveness of B. valdivianus and L. perenne was evaluated when sown in pots in a glasshouse as monocultures or a mix (50/50 %) with restricted water availability. The water restriction treatments were as follows: 80–85 % field capacity (FC), 45–50 % FC and 20–25 % FC, maintained for 1196 growing degree days. For both species, dry matter (DM) accumulated per plant and per pot decreased similarly with increasing water restriction, but at tiller level, resource allocation differed, for B. valdivianus root growth was accentuated over aerial development, but this was less so for L. perenne. The foliage mass per tiller for B. valdivianus decreased relatively more than that for L. perenne with increasing water restriction. As monocultures, B. valdivianus produced larger tillers than L. perenne, such that B. valdivianus tillers had 2.2 times greater lamina mass, 3.6 times more leaf area and 2.5 times greater root mass than those of L. perenne. However, L. perenne produced a larger number of smaller tillers that enabled foliage, root and total mass at plant level, to be similar to that of B. valdivianus. Within the mixed pasture, L. perenne tiller density increased compared with when grown as a monoculture, but not for B. valdivianus. The results of the study suggested that L. perenne and B. valdivianus have differences in growth strategies that allow them to survive under environmental stress and competition. Competitiveness increased for L. perenne aboveground without water restriction and that for B. valdivianus increased belowground as water restriction was increased.  相似文献