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《畜牧兽医学报》2016,(6)
本研究对不同生长速度的鸭品种出雏后体重及胸、腿肌重的生长发育进行差异分析,为系统了解鸭骨骼肌的动态发育变化奠定基础。测定高邮鸭和金定鸭0~70日龄14个生长点的体重、胸大肌重和腓肠肌重,比较不同品种各个生长点体重、胸大肌重、腓肠肌重的累积生长、绝对生长、相对生长,并用Gompertz、Logistic和Bertalanffy3种模型拟合生长曲线,根据模型的参数计算拐点重以及拐点日龄。结果:1)从出雏开始高邮鸭体重和腓肠肌重就显著高于金定鸭,胸大肌重从4日龄开始有显著差异。28~70日龄高邮鸭体重、胸大肌重和腓肠肌重分别是金定鸭的1.41倍、1.50倍和1.20倍。2)高邮鸭体重、胸大肌重和腓肠肌重的生长速度均大于金定鸭;达到最大生长速度时间点无品种差异,体重的最大生长点为20日龄,胸大肌重的最大生长点为56日龄,腓肠肌重的最大生长点为20日龄;3)通过拟合数据发现,0~16日龄高邮鸭体重生长强度高于金定鸭,而胸大肌重和腓肠肌重生长强度低于金定鸭;其后体重、胸大肌重和腓肠肌重生长强度在两个品种鸭之间均渐趋相同。体重、胸大肌重和腓肠肌重生长强度变化规律无品种差异。4)鸭胸大肌重的拐点日龄(52日龄)迟于腓肠肌重的拐点日龄(16.5日龄);16日龄之前胸大肌重生长强度低于腓肠肌,16日龄之后高于腓肠肌。0~28日龄胸大肌生长强度缓慢减小而后期迅速减小,腓肠肌重生长强度早期迅速减小而后期缓慢减小。28~70日龄高邮鸭胸体指数高于金定鸭,而腿体指数显著低于金定鸭,这些都表明28~70日龄鸭胸肌的生长强于腿肌。在生长环境一致的条件下,不同肉用性能的鸭体重、胸大肌重和腓肠肌重的生长发育变化规律均没有差异,但胸、腿肌之间的生长发育规律差异较大,早期胸肌生长慢于腿肌,后期快于腿肌,在肉用性能上胸肌的贡献高于腿肌。 相似文献
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用北京鸭，金定鸭，白番鸭三元杂交培育出优良商品鸭，杂交后代６０日龄栏体重达２．４９公斤，肉料比为１：３．３，且已在龙海市推广２８００万头。 相似文献
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金定鸭是我国优秀的蛋用鸭地方品种之一,目前在国内许多地区都有较大规模的饲养。根据金定鸭的生理特征及生活习性,在饲养管理上可分为如下四个阶段: (一)雏鸭期的饲养管理 指从出壳至20日龄的小鸭。雏鸭出壳时体重平均为42克左右,怕冷又怕热, 相似文献
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金定鸭产蛋期粗蛋白与代谢能需要量试验 总被引：3，自引：0，他引：3
<正> 金定鸭系高产品种之一,其主要生产性能达到了国内先进水平,但对其营养需要尚缺乏较系统的研究。我们从1990年4月至1990年7月对金定鸭产蛋期日粮中不同粗蛋白和能量水平进行试验,为探求金定鸭产蛋期的配合日粮提供依据。一、材料与方法试验鸭选自沈阳辉山风景区管理处养殖场鸭群。选择发育良好、体重基本一致的青年鸭3000只,均分为6组。各组在外界环境和饲养管理条件均相同的情况下,实行舍饲圈养。各组日粮和营养水平见表1。36～38周龄为预试期,逐步掺入试验饲料,39～61周龄末全部喂试验饲料。管理按常规进行。 相似文献
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<正>经廿余年本品种选育而成的金定鸭,其生产性能比原始地方品种显著提高,群鸭年均产蛋数增加50枚以上,蛋重亦提高6克以上(1958,10～1959,10原始实验对照群,年平均产蛋数为212.60枚,蛋重为63.25克)。现鸭群体态外貌、羽色、蛋壳颜色已趋一致,且遗传性稳定,已成为国内优秀蛋鸭培育品种,其生产性能可与当今世界各蛋鸭品种相媲美。 就金定鸭品种的内部结构而言,它属于单一大品种的范畴,尚未利用其品种内的异质性并促进其分化,从而建立起具有一定特色的品系,这是它美中不足之处。为使金定鸭品种内的结构渐趋合理和完善,更有力地促进它的生存和发展,并向现代化品种的方向迈进, 相似文献
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利用微卫星DNA多态性预测半番鸭的杂种优势 总被引：1，自引：0，他引：1
为探究微卫星DNA多态性与鸭肉用性能杂种优势的相关关系,选取10对微卫星标记对金定鸭、樱桃谷鸭、F1(樱桃谷鸭×金定鸭)和番鸭进行遗传多样性检测。利用ONEDscan、GENEPOP、Mstools软件对目的基因进行分型,计算遗传多样性参数以及群体间标准遗传距离,并测定半番鸭各杂交组合F1代体重杂种优势。结果表明:在4个鸭群体共检测到52个等位基因,金定鸭、F1(樱桃谷鸭×金定鸭)、樱桃谷鸭与番鸭群体间标准遗传距离分别为0.57678、0.52220、0.46356,樱桃谷鸭与金定鸭遗传距离为0.38949。并根据遗传距离,采用对数曲线模型对半番鸭体重杂种优势进行了预测,χ2检验结果显示,预测结果与实验测定结果无显著性差异,表明本研究建立的根据微卫星DNA多态性预测半番鸭部分生长阶段体重杂种优势是可行的。 相似文献
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利用形态学、组织学方法,对初生至300日龄连城白鸭睾丸生长发育进行了初步研究,以探讨其胚后发育和性成熟特点。结果显示:连城白鸭睾丸大小、重量、睾丸指数及睾丸曲精小管组织结构均呈明显的日龄性变化。随着日龄增长,连城白鸭双侧睾丸体积、双睾重、睾丸指数逐渐增大,曲精小管管径和上皮高度逐渐增大,细胞层数增多,间质组织先增多,而后又减少,白膜厚度也先增大后减小。随着性成熟的开始,精原细胞不断分裂分化,出现了不同发育阶段的生精细胞。连城白鸭睾丸的胚后发育过程分为4期:30日龄之前为精原细胞增殖和曲精小管形成期,30~60日龄为初级精母细胞增殖期,60~75日龄为次级精母细胞增殖期,90~120日龄为精子形成期。 相似文献
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《African Zoology》2013,48(2):287-293
Sexual size dimorphism in the medium-sized lizard Oplurus cuvieri cuvieri, which is endemic to the dry deciduous forest of Madagascar, is presented. Adults are sexually dimorphic in body size, head size, and tail length. Males have a greater snout–vent length (SVL), head depth, head width, jaw length, tail length and body mass than females. Juvenile males have greater annual SVL growth rates than juvenile females, contributing to adult sexual size dimorphism. Moreover, the rates of increase in head depth and width differ significantly between the sexes after reaching maturity so that adult males have larger heads for a given body size than adult females. I suggest three proximate mechanisms that may cause sex-related differences in adult head size of O. c. cuvieri based on natural selection; to reduce intersexual food competition, sexual selection involving mate acquisition in males, and ontogenetic change of allometry to improve reproductive output in females. 相似文献
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叶城沙蜥是一种主要分布于中国新疆南部地区的蜥蜴,通过测量和比较采自新疆塔里木盆地且末县叶城沙蜥的个体大小以及口宽等8个形态特征,研究了叶城沙蜥的两性异形。研究共采集叶城沙蜥62只,其中成年雌性个体27只,雄性个体35只。结果显示:(1)叶城沙蜥雌雄性成体的体长有显著差异,雄性大于雌性,表明叶城沙蜥具有雄性偏大的两性异形模式;(2)叶城沙蜥其他身体形态特征中尾长、腹长和头长3个特征有显著差异,其中雄性的尾长和头长大于雌性,而雌性的腹长大于雄性;(3)叶城沙蜥雌雄性个体间的口宽、眼间距等其他形态特征则没有显著差异。叶城沙蜥的两性异形表现为雄性大于雌性,并且雄性具有更大的头部和更长的尾部,雌性具有更长有腹部,这可能是雄性个体面临的性选择压力与雌性个体面临的繁殖压力共同作用的结果。 相似文献
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辽东白嗉鸭是一个具有独特外貌特征和生产性能的地方鸭种资源类群,对丰富世界鸭种遗传资源的多样性有着重大意义。对该鸭种的种质性能进行测定,结果:从羽色及蹼色可分为3个亚型,即黑羽白嗉、银灰羽白嗉、金掌白嗉;体形、体重有兼用型的特征,成年公鸭屠宰率84.1%,胸肌率17.6%,腿肌率16.4%。银灰羽和黑羽类群公、母鸭的绝对增重峰值期均出现在8~9周龄(28~33g/d),相对增重率的峰值均出现在4周龄(80.43%~85.38%);银灰羽类群公、母鸭的初生重及24周龄体重略高于黑羽类群,但差异不显著(P>0.05);0~6周龄成活率98.6%,7~24周龄成活率97.8%。开产日龄为184d,核心群入舍母鸭年均产蛋量(249±12)个、加权年均产蛋量(285±16)个;普通群入舍母鸭年均产蛋量(174.6±18)个、加权年均产蛋量(186.3±16)个;自然交配公、母比例为1∶9,饲养只日受精率为91.32%。 相似文献
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The extent of sexual selection in two girdled lizard species was evaluated by measuring sexual dimorphism in those characters normally affected by sexual selection. Neither Cordylus niger, a cool-adapted species, nor C. cordylus, a warm-adapted species, displayed any notable sexual differences in asymptotic body sizes, but both species displayed slight dimorphism in head size measurements. The C. niger sample contained more large males than large females, which may be attributed to a lower growth rate in females. In the cool Saldanha area, females of both species lack generation glands. In the warmer Gansbaai area, these glands are present in females of C. cordylus, but in lower numbers than in males. Sex ratios favouring females, have been recorded for both species. The observed sexual dimorphism in the two species seems to be mainly the result of differential energy allocation by females, and not of sexual selection perse. 相似文献
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《African Zoology》2013,48(2):151-164
Copadichromis chrysonotus is a zooplanktivorous cichlid member of the diverse fish community inhabiting Lake Malawi’s rocky, littoral habitat. Like most Lake Malawi cichlids, this species’ reproductive strategy is based on maternal mouthbrooding, but it is the only littoral species known to spawn in the open water without a substrate-based territory. This studyinvestigated length at maturity, sexual dimorphism, spawning behaviour, breeding seasonality, fecundity, fertility, egg size, and brooding habits of C. chrysonotus in southern Lake Malawi. Males in breeding colouration aggregated in sheltered areas at least several metres deep, and each male defended a mobile breeding territory near the surface while attempting toattract females. Breeding was mostly continuous from August to May, with peaks in August–September and January–March. A major lull in breeding activity occurred in May and June. Mean fecundity and fertility increased significantly with female total length, while mean egg length, mean egg mass and gonadosomatic index did not increase significantly with female totallength. Females brooded their young up to 15–16 mm total length before abandoning them. Open-water spawning by C. chrysonotus may be an adaptation to reduce both egg predation during spawning and competition for substrate-based breeding territories. 相似文献
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Materials suitable for anatomical research of raptorial birds are rare. Bird‐eating raptors show distinct inter‐sexual differences in body size and parental roles. The large females catch larger prey and prepare small morsels to feed their young using their hooked beaks. Here, we investigated the architectural properties of different jaw muscles of the Japanese sparrowhawk (Accipiter gularis) and examined whether there is sexual dimorphism in their architectural design. The results showed that musculus depressor mandibulae, the opener of the lower jaw, was characterized by relatively long fascicle length, whereas musculus pterygoideus was characterized by its larger mass and physiological cross‐sectional area (PCSA) in both sexes. Females have the potential capacity to produce rapid and strong bites by their significantly longer fascicle length of M. depressor mandibulae and larger mass and PCSA of M. pterygoideus. For body size‐matched gender, jaw muscles of males had fibres of relatively longer length than females, enabling greater velocity and excursion. Architectural characteristics of jaw muscles, together with the absolute dimorphism (the fascicle length of M. depressor mandibulae, the muscle mass and PCSA of M. pterygoideus) and relative dimorphism in the muscle mass of M. pterygoideus, reflect dietary difference and asymmetric parental roles between the sexes. 相似文献
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采用qPCR分析生肌调节因子MyoD1基因在高邮鸭和金定鸭胚胎期及初生早期(13、17、21、25、27胚龄和出雏后7日龄)胸肌发育中的表达模式以及与胚胎和胸肌发育的相关性。结果表明,MyoD1 mRNA在两个品种鸭胸肌早期发育中表现出一致的表达规律,均呈“波浪形”,在13胚龄时表达量相对较高,17胚龄时下降,21胚龄时上升到最高,随后下降,出雏后又维持较高水平;品种间比较结果显示除了在25胚龄时金定鸭胸肌中MyoD1 mRNA表达量稍低于高邮鸭,在其他所检测的胚龄/日龄中,金定鸭胸肌中MyoD1 mRNA表达量均高于高邮鸭胸肌中的表达量(P>0.05);高邮鸭胸肌MyoD1 mRNA表达与胚胎和胸肌发育无显著相关性,而金定鸭胸肌中MyoD1 mRNA的表达与其胚胎和胸肌发育呈强负相关(P胚重=0.048;P胸肌重=0.006)。MyoD1基因参与鸭胚胎期及出雏早期胸肌的发育,胸肌中MyoD1基因表达分析研究为进一步深入研究MyoD1基因在胚胎期胸肌发生过程及其调控机理中的功能提供一定的理论依据 相似文献
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《African Zoology》2013,48(1):38-44
We examined 170 museum specimens of the southern African gekkonid lizard Homopholis wahlbergii, to quantify sexual dimorphism, male and female reproductive cycles and diet. The largest male and female we recorded were 116 and 119 mm snout–vent length (SVL) respectively. We compared SVL, tail length, head length, head width and eye diameter and found no evidence of sexual dimorphism in any of these characters. The smallest female with thickened muscular oviducts and follicles, indicating sexual maturity, was 59 mm SVL, but the smallest female we found with fully developed eggs was 85mmSVL. Virtually all females larger than 59 mm appeared to be in some stage of reproduction, suggesting that females reproduce every year once they reach sexual maturity. Egg size ranged from 17–19mm long. Egg size was not correlated with maternal SVL. We found adult females with ready-to-lay eggs during the warmer months of the year, but not during winter and spring. The smallest sexually mature male was 72 mm SVL. Virtually all males larger than this size displayed at least semi-turgid testes and most adult male testes were at least semi-turgid for much of the year. The only significant decrease in testicular activity was in mid-winter (June–August), thus, spermatogenesis is closely tied to female follicular development and ovulation. Velvet geckos are largely insectivorous (92%) and feed on a broad spectrum of prey. Their diet was dominated both numerically (34%) and volumetrically (22%) by beetles. Lepidoptera were the next most important prey category, suggesting that they exploit both terrestrial and flying invertebrates. They are unusual among lizards because they feed on millipedes. Males and females had very similar diets which may be explained by their lack of sexual dimorphism, although females tended to eat a greater volume of prey. Interestingly, less than half (37%) of the lizards examined contained prey items, suggesting that most individuals were not in positive energy balance. We also found evidence of prey size selection as a function of gape size, such that larger geckos took advantage of larger prey items. 相似文献
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鸭胚骨骼肌不同组织Myf6基因表达的发育性变化研究 总被引：1，自引：1，他引：0
为研究Myf6基因对鸭肌肉发育的影响,本试验利用实时荧光定量PCR绝对定量技术检测Myf6基因在高邮鸭和金定鸭胚胎期第13、17、21、25、27天及出生后7日龄胸肌、腿肌发育过程中的表达量。结果显示,Myf6基因在2个品种的胸肌和腿肌中均有表达,在不同品种同一肌肉组织中的表达变化规律一致,而在不同肌肉组织中的表达模式不同,其中在胸肌组织中21胚龄时表达量最高,随后表达量下降,维持相对较高表达水平;在腿肌组织中13胚龄时表达量较高,17胚龄时达到最高,随后表达量有所降低,并在21胚龄后急速下降至极低水平,但其表达在胚胎期后期(27胚龄)及初生期(7日龄)又有缓慢上升趋势。上述结果表明,Myf6基因参与了胸、腿肌组织的发育,在胸、腿肌中表达模式不同,推测Myf6基因在胸、腿肌中的调控存在差异,可能与其胸、腿肌不同肌纤维的发育与分化有关。 相似文献