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991.
丝羽乌骨鸡快大型新品系早期生长发育规律的研究 总被引:8,自引:0,他引:8
本试验对丝羽鸟骨鸡快大型新品系的早期生长发育规律及肉用性能进行了系统的研究。利用Logistic模型确定了快大型新品系丝羽乌骨鸡的生长模型,并以此制定了标准生长曲线。研究结果表明,其生长拐点为:10.5周龄:在14周龄时体重约1.0kg,为较适合的上市日龄, 相似文献
992.
993.
潮间带垒石蒙网养鲍技术研究 总被引:1,自引:0,他引:1
1994年4月~1995年10月,在4个岩礁区共设置136个石垛,放养壳长1.3~3.0cm鲍苗55.1万只,进行潮间带垒石蒙网养鲍试验。对场址选择、放养密度、规格、投饵方法等进行了研究。结果:产商品鲍19.254t,平均亩产1397.8kg,平均壳长6.81cm,平均个体重39g,成活率89.6%,实现产值693.144万元、利润352.81万元。专家鉴定认为,养殖方式为国内首创,技术水平属世界先进。 相似文献
994.
花生籽仁大小相关性状是决定花生产量的直接因素。为发掘与花生籽仁大小相关的QTL,本研究以中花16×J11构建的RIL群体为材料,得到了一张包含289个SSR标记、21个连锁群、覆盖长度为947.3cM的遗传连锁图谱。连续2年对籽仁大小相关性状鉴定表明,各性状在群体中变异广泛,呈典型正态分布,且大部分性状间显著相关。结合本研究构建的遗传图谱,利用WinCart2.5进行QTL定位分析,2年共检测到66个QTL,贡献率为3.23%~33.01%。与籽仁长(SL)、籽仁宽(SW)、籽仁长宽比(LWR)和百仁重(HSW)相关的QTL分别有18、16、18和14个。在这些QTL中,A05染色体上的区间A05A1500-A05A1530同时存在控制籽仁长(qSLA05.1和qSLA05.2)和百仁重的相关的QTL(qHSWA05.1);B06染色体上的区间A06B135-A06B113同时存在控制籽仁宽(qSWB06.2和qSWB06.4)和百仁重相关的QTL (qHSWB06.4),这些稳定存在的主效QTL将为花生产量相关性状的精细定位和分子育种奠定基础。 相似文献
995.
类胰岛素生长因子1型受体(IGF-1R)基因是类胰岛素生长因子(IGFs)在生物体内发挥作用的主要效应器,对机体生长发育进程中有重要影响。为探讨IGF-1R基因多态性与蛋用鹌鹑体尺性状的相关性,采用PCR产物直接测序方法对中国黄羽鹌鹑、北京白羽鹌鹑、朝鲜鹌鹑3种蛋用鹌鹑的IGF-1R基因进行多态性分析,并对IGF-1R基因的多态性与鹌鹑体尺性状进行相关性分析。结果表明,在3个蛋用鹌鹑群体中检测到IGF-1R基因A57G和A72T两个突变位点,A57G位点发生了A/G碱基突变,有AA、AG和GG三种基因型;A72T位点发生了A/T碱基突变,有AA、AT和TT三种基因型。中国黄羽鹌鹑的A57G位点对胫长、胸骨长和胫围有显著影响(P<0.05),A72T位点对体质量和胸骨长有显著影响(P<0.05),组合基因型AGAA对体质量有显著影响(P<0.05),组合基因型AAAA对胫长、胸骨长、胫围有明显影响(P<0.05)。北京白羽鹌鹑的A57G位点对体质量、胫长、体长、胫围有显著影响(P<0.05),A72T位点对胸骨长有显著影响(P<0.05),组合基因型AAAA对体质量和胸骨长有显著影响(P<0.05),组合基因型AAAT、GGAA、GGAT对胫长有显著影响(P<0.05),组合基因型GGAA对胸深有显著影响(P<0.05)。朝鲜鹌鹑的A57G位点对体质量有显著影响(P<0.05),A72T位点对胸骨长和胫围有显著影响(P<0.05),组合基因型AGAA对体质量有显著影响(P<0.05),组合基因型AGAT对胫长和胸宽有显著影响(P<0.05)。因此,IGF-1R基因可以作为候选基因应用于蛋用鹌鹑体尺性状的分子标记辅助选择。 相似文献
996.
大量研究表明沉积物的粒度和粘土矿物可以作为研究环境演变的载体。玛纳斯河兴农湖剖面位于新疆维吾尔族自治区克拉玛依市附近的一个农场内。本文分析了该剖面的粒度变化特点和粘土矿物的类型与含量变化。研究表明,兴农湖剖面以湖相沉积为主,位于古玛纳斯湖的边缘,是古玛纳斯湖的一部分。粘土矿物主要由伊利石、蒙皂石、高岭石和绿泥石组成。根据粒度和粘土矿物分析,将兴农湖沉积环境演变划分为9个阶段。 相似文献
997.
Sting nematode (Belonolaimus longicaudatus Rau) has become a primary factor limiting citrus production in localized regions of the central Florida sandridge citrus production area, making the development of resistant rootstocks a new breeding objective. In efforts to develop a replacement rootstock for the widely adapted sour orange, our focus has been on somatic hybridization of selected mandarin + pummelo combinations [Grosser, J.W., Gmitter, Jr., F.G., 1990. Protoplast fusion and citrus improvement. Plant Breed. Rev. 8, 339–374; Ananthakrishnan, G., Calovic, M., Serrano, P., Grosser, J.W., 2006. Production of additional allotetraploid somatic hybrids combining mandarins and sweet oranges with pre-selected pummelos as potential candidates to replace sour orange rootstock. In Vitro Cell. Dev.: Plant 42, 367–371], since sour orange is probably an introgression hybrid of mandarin and pummelo as suggested by molecular marker analyses [Nicolosi, E., Deng, Z.N., Gentile, A., La Malfa, S., Tribulato, E., 2000. Citrus phylogeny and genetic origin of important species as investigated by molecular markers. Theor. Appl. Genet. 100, 1155–1166; Gulsen, O., Roose, M.L., 2001. Lemons: diversity and relationships with selected Citrus genotypes as measured with nuclear genome markers. J. Am. Soc. Hort. Sci. 126, 309–317]. Somatic hybrid plants were produced from four new mandarin (C. reticulata Blanco) + pummelo (C. grandis L. Osbeck) parental combinations by fusing embryogenic suspension culture-derived protoplasts isolated from selected mandarins with leaf protoplasts of pummelo seedlings previously selected for tolerance/resistance to the sting nematode (B. longicaudatus Rau) as follows: Amblycarpa mandarin + ‘Liang Ping Yau’ (seedling) pummelo seedling SN7; Amblycarpa mandarin + ‘Hirado Buntan Pink’ (HBP) pummelo seedling SN3; Murcott tangor + pummelo seedling SN3; and Shekwasha mandarin + pummelo seedling SN3. Somatic hybridization was verified by ploidy analysis (via flow cytometry) and RAPD analyses. Mandarin parents were selected for wide soil-adaptation and ability to produce friable embryogenic callus lines. Pummelo seedlings used as leaf parents were identified from a previous screen of large seed populations (200 each) from four pummelos for resistance to sting nematode as follows: ‘Hirado Buntan Pink‘; ‘Red Shaddock‘; ‘Large Pink Pummelo’ and a seedling pummelo of ‘Liang Ping Yau‘. Ten resistant/tolerant pummelo seedlings were selected from the 800 pummelo seeds planted in the screen for further study. The four new somatic hybrids have been propagated to evaluate their horticultural performance and resistance to the sting nematode. These potential somatic hybrid rootstocks should also have potential to control tree size due to polyploidy. 相似文献
998.
LI Hongmin DONG Li HU Zhenzhen MAO Junzhou ZHANG Yongsheng LIU Jun YU Lihuai 《中国畜牧兽医》2007,47(11):3484-3492
The experiment was conducted to explore the effects of attapulgite nano zinc oxide (ANZ) on antioxidant and immune functions in spleen of weaned piglets.210 weaned piglets of similar weight were randomly divided into 7 groups with 6 replicates in each group and 5 piglets per repeat.The treatments were control group (CON group,basal diet),antibiotic group (ANT group,basal diet+antibiotic),zinc oxide group (ZO group,basal diet+3 000 mg/kg zinc oxide),nano-zinc oxide group (NZO group,basal diet+800 mg/kg nano-zinc oxide),low,middle and high dose attapulgite nano zinc oxide groups (LANZ group,basal diet+700 mg/kg attapulgite nano zinc oxide;MANZ group,basal diet+1 000 mg/kg attapulgite nano zinc oxide;HANZ group,basal diet+1 300 mg/kg attapulgite nano zinc oxide).The results showed that:Compared with CON group,spleen index in ZO,MANZ and HANZ groups increased significantly (P<0.05).Compared with CON and ANT groups,the area of spleen cells in NZO,LANZ,MANZ and HANZ groups increased significantly (P<0.05).Compared with other treatment groups,the size of spleen cells in MANZ group increased significantly (P<0.05).Compared with CON,ANT,NZO and HANZ groups,superoxide dismutase (SOD) activity in MANZ group increased significantly (P<0.05).Compared with ZO and NZO groups,catalase (CAT) activity in LANZ,MANZ and HANZ groups increased significantly (P<0.05).Compared with ZO group,the content of malondialdehyde (MDA) in NZO,LANZ,MANZ and HANZ groups decreased significantly (P<0.05).Compared with CON group,the content of interferon-γ (IFN-γ) in ANT,MANZ and HANZ groups decreased significantly (P<0.05).Compared with CON,ANT,ZO and NZO groups,the content of tumor necrosis factor-α (TNF-α) in MANZ and HANZ groups decreased significantly (P<0.05).Compared with ANT group,the content of interleukin-1 β (IL-1 β) in MANZ group decreased significantly (P<0.05).Compared with ANZ、ZO and NZO groups,the content of interleukin-10 (IL-10) in MANZ and HANZ groups increased significantly (P<0.05).Compared with CON,ANT and ZO groups,the content of interleukin-12 (IL-12) in LANZ and MANZ groups increased significantly (P<0.05).In conclusion,attapulgite nano zinc oxide could increase organ index and cell size of spleen,improved the antioxidant enzymes activity in spleen,decreased the content of proinflammatory factors,increased the content of anti-inflammatory factors,and enhanced the antioxidant and immune functions of weaned piglets.The optimum addition level of attapulgite nano zinc oxide was 1 000 mg/kg in this experiment. 相似文献
999.
1000.
Jos ngel Gmez Toms Landete-Castillejos Andrs Jos García Laureano Gallego 《Livestock Science》2006,105(1-3):27-34
Lactation appears to be an influential factor for the adult size of male deer and thus, it could also influence the size of the antlers. This study examined the effects of lactation on body weight and antler size of male Iberian red deer up to 2 years of age. Several body and antler measurements were related to the production and composition of milk and calf growth during lactation. Results showed that calf weight gains during lactation affected body weight and other parameters of calves at 1 year of age, and there is evidence that, even in ad libitum food conditions during post weaning period, some lactation effects could extend up to 2 years of age. High percentage of milk protein resulted in increased antler weight or length. Results also suggested that body growth during this early stage might affect antler size positively through growth precocity. Thus, males that reached a higher weight at weaning also developed antlers earlier. Antlers that developed earlier were also heavier and had a greater base perimeter. 相似文献