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31.
32.
丝羽乌鸡蛋品质对种蛋受精率和受精蛋孵化率的影响   总被引:2,自引:0,他引:2  
试验就丝羽乌鸡蛋品质因素对种蛋受精率和受精蛋孵化率的影响进行了研究.结果显示,哈氏单位和蛋白高度越大,受精率和受精蛋孵化率越高(P<0.01);蛋重对受精率有一定的影响,蛋重与受精率呈一定正相关关系(r=0.0619,P<0.1),随着蛋重增加,受精率也会增大;蛋壳强度与受精蛋孵化率呈一定负相关关系(r=-0.1808,P<0.1),蛋壳强度太大的鸡蛋其受精蛋孵化率反而下降;蛋壳颜色与受精率呈强的负相关关系(r=-0.2848,P<0.01),即蛋壳颜色越深的鸡蛋其受精率越高;而蛋黄颜色与受精蛋孵化率呈强的负相关关系(r=-0.2328,P<0.05),即蛋黄颜色越浅的鸡蛋受精蛋孵化率越高;蛋形指数、蛋壳厚度、蛋比重等指标对受精率及受精蛋孵化率未有显著影响.  相似文献   
33.
Transporting hatching eggs from Hungary and incubating them abroad revealed lower hatchability compared to when the eggs were incubated in Hungary. Following transport, there were higher embryo losses and, notably, more malformed embryos. The aim of these initial trials was to determine if a testing device (crazy fit massage machine (CFM machine)) was able to replicate and model the mechanical impacts experienced during transport and reproduce the reduction in hatchability and increase the level of malformed embryos as observed in commercial practice. Tinytag~ high sensitivity shock and vibration loggers were used to monitor the impacts under field and trial conditions. Applying single 10 min treatments on the CFM machine, which used the same frequency (10-30 Hz) as the eggs experience under field conditions, induced the negative effect of transport, and lower hatching results were experienced. Three trials were conducted. Treated eggs in Trials 1 and 2 received automatically and periodical changing vibration in a range between 10-30 Hz for 10 min while in Trial 3 two different levels of impact were applied at 20 Hz and 30 Hz, respectively. Hatchability decreased due to the treatment significatly only in Trial 3. Significant differences were also detected in early dead levels in Trials 2 and 3 and the occurrences of malformation in Trials 1 and 3. All these results are in accordance with the field experience. Thus, the trials which examined the equipment were able to produce mechanical impacts that were repeatable in order to set up statistically reliable trials on hatching eggs.  相似文献   
34.
The current research was conducted to determine the comparison of hatchability and some egg quality characteristics in spotted and unspotted partridge (Alectoris chukar) eggs. The research was carried out on 51 male and 102 female chukar partridges (Alectoris chukar) aged 50 wk, which were raised at the Research and Application Farm of the Faculty of Veterinary Medicine of Selcuk University. In total, 244 spotted and 261 unspotted eggs were used in the research. The hatching eggs were stored at 75% RH and 13°C for 14 d. Thirty spotted and 30 unspotted eggs laid on the same day were used for the evaluation of egg quality characteristics. Egg weight, chick weight, egg weight loss during the hatching period, shape index, hatchability, and some egg quality characteristics were evaluated at the end of the research. Spotted eggs exhibited a higher fertility and hatchability, as well as a lower percentage egg weight loss and embryonic mortality when compared with unspotted eggs. No significant differences were observed between spotted and unspotted eggs for egg weight, chick weight, shape index, specific gravity, albumen height, Haugh unit, yolk color green-red chromaticity (a*), albumen pH, and yolk pH. Spotted eggs had higher eggshell color a*, eggshell color blue-yellow chromaticity (b*), and eggshell strength, as well as a lower eggshell color light-dark chromaticity (L*), yolk color L*, and yolk color b* scores when compared with unspotted eggs. It was demonstrated that spots on the eggshells of chukar partridges (Alectoris chukar) improved their hatchability by affecting various quality characteristics of their eggs. It was concluded that spotted eggs are more suitable for hatching.  相似文献   
35.
对不同胚龄的瘤头鸭受精蛋进行“喷水凉蛋”处理,其孵化率显著高于对照组(P<0.01);其中以10胚龄开始“喷水凉蛋”组孵化效果最佳,平均孵化率达83.95%.孵化至第10天,瘤头鸭胚蛋内脂肪含量减少0.38%,蛋温升到38.2℃,胚龄增长至26—27天时(尿囊萎缩)胚胎主要吸收蛋黄营养,蛋温也随之升高到39.5℃.孵化过程采取“喷水凉蛋”可防止蛋温过.高,保持孵化温度的稳定.由于瘤头鸭蛋壳(0.44mm)和壳膜(0.107mm)都比鸡蛋厚,而气孔数(68个/m~2)又比鸡蛋少,故对番鸭蛋喷洒温水可洗去胶质膜,使蛋壳、壳膜不断进行收缩和扩张,加大蛋壳的通透性,促进水分代谢和气体交换,从而增强胚胎活力,起到提高孵化率的作用.  相似文献   
36.
鳖人工繁殖有关技术及影响鳖卵受精率、孵化率及稚鳖越冬成活率的研究表明,2a供试亲鳖8100只,产卵172229粒,受精率88.83%,孵化稚鳖141852只,孵化率为92.72%,其中利用自制亲鳖促性腺发育配合饲料投喂比天然饲料投喂的雌亲鳖产卵量提高23.32%;利用LRH-A对亲鳖进行人工催产的受精率为91.82%,比自然产卵受精率(85.13%)提高6.69%;保温越冬稚鳖4800只,成活率95.3%,比常温越冬成活率(81.75%)提高13.55%;平均饲养稚鳖229d,增重倍数为5.14,饲养幼鳖3400只,成活率97.01%,增重倍数为7.63。  相似文献   
37.
为探索两广二号蚕种冷藏期限问题,2018—2019年进行了冷藏时间、繁育期对两广二号越年种孵化率的影响试验。试验表明:冷藏时间与两广二号孵化率呈极显著负相关,与皓月×菁松孵化率相关不显著;两广二号不同繁育期、冷藏时间及二者交互作用的孵化率差异极显著;两广二号春制越年种冷藏安全期为111 d,秋制种冷藏安全期为162 d。  相似文献   
38.
胚胎的冷冻是用二步降温法,将胚胎降至-25℃,并直接投入液氮。试验Ⅰ,将6~8日龄的牛胚胎置于显微镜下,按发育期把胚胎分成桑椹胚、早期囊胚、囊胚、扩展囊胚四个阶段,然后分别平衡在1.5mol/L甘油+0.25mol/L蔗糖PBS液中,20min后进行冷冻。解冻后,各阶段的胚胎孵化率分别为:29.0%,73.2%,74.6%,61.2%。桑椹胚的孵化率极显著(P<0.01)地低于其它三个阶段的胚胎,其它三个阶段之间无显著差异((P>0.05)。试验Ⅱ,将7日龄的囊胚,在显微镜下鉴定质量并分为1~5级,仅1,2级胚胎用于冷冻。试验结果表明:每管装2枚胚胎时,有1枚胚胎以上孵化的细管数,1级的有93.8%(45/48),2级的有77.4%(24/31),它们之间差异显著(P<0.05)。每管装3枚胚胎时,有2枚胚胎以上孵化的细管数,1级的有87.5%(42/48),2级的有68.0%(17/25),二者间差异显著(P<0.05)。本研究结果表明:不同阶段和质量的牛体外培养胚胎冷冻后对存活率有显著的影响。  相似文献   
39.
中国卤虫卵孵化特性的研究   总被引:13,自引:2,他引:13  
杨娜  卞伯仲  李明仁 《水产学报》1989,13(4):285-297
本文对山东埕口盐场、海南岛莺歌海盐场及青海柯柯盐湖天然采集的卤虫卵进行了孵化特性研究。埕口、莺歌海及柯柯的虫卵壳厚分别为9.7,11.4及13.2μm。在放入海水中进行孵化前上述三品系的卤虫卵分别在自来水中浸泡2,3及4小时能获得最佳孵化率。它们的最适孵化温度分别为25.6~28.5℃,27.0~30.0℃及27.0~33.0℃。最适孵化盐度分别为30,20及35%。孵化的同步性以“莺歌海”为最好,为6.4小时,“埕口”次之,为6.5小时,“柯柯”为7.4小时。 实验室内培养产卵后24小时内收集的虫卵用下列方法处理能终止虫卵的滞育状态:(1)埕口卤虫卵:浸泡于粗盐饱和溶液中2~3个月,孵化率可达91~94%。(2)莺歌海卤虫卵:浸泡于粗盐饱和溶液中2~5个月,孵化率可达80~91%。(3)柯柯卤虫卵:置于5℃2~3个月孵化率可达96~98%。用3%H_2O_2及3%甲醛溶液处理对终止滞育状态没有作用。天然采集的三个品系的卤虫卵用3%H_2O_2或3%甲醛溶液或用去壳溶液处理均可以提高孵化率。  相似文献   
40.
贵妃鸡蛋重和繁殖率关系探讨   总被引:4,自引:0,他引:4  
选28 ̄29周龄贵妃鸡新产种蛋,按蛋重分4组作蛋重和繁殖率关系试验。结果表明,蛋重41 ̄45克组受精率,孵化率和健雏率分别达98.11%,94.23%和97.96%,极显著高于蛋重30克和31 ̄35克组,45克内蛋重与三率呈强正相关,小于30克重组三率极显著低于其它组(P〈0.01),试验说明贵刀鸡种蛋最佳蛋重为41 ̄45克,小于30克的蛋不宜作种用。  相似文献   
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