椰子织蛾种群繁殖特征

本文研究了椰子织蛾Opisina arenosella Walker种群繁殖的特征。2015年每月从儋州市野外采集椰子织蛾,收集当天羽化的成虫,记录成虫的产卵前期、单雌产卵量、卵的孵化率、初孵幼虫数以及成虫寿命。结果表明:1月份的气温最低,雌成虫的产卵前期最长,为(3.00±0.21)d;5、6月气温最高,产卵前期次之;其他月份的产卵前期较短。11月份椰子织蛾的单雌产卵量最高,为(231.07±19.55)粒;3、4、7、8、9、10月份的产卵量次之;1、2、5、6、12月份的单雌产卵量最低。1月份(低温)椰子织蛾卵的孵化率最低,为(2.70±2.01)%;2—12月份椰子织蛾卵的孵化率差异不显著。1月份的初孵幼虫数最少,为(4.17±2.94)头;5、6月份的较少,分别为(54.04±8.18)、(52.31±10.81)头;3月份的最多,为(87.89±14.94)头。低温使成虫的寿命延长;各月雌成虫的寿命短于雄成虫的寿命;5、6月份雄成虫的平均寿命分别为(7.08±0.68)、(7.67±0.84)d,雌成虫的平均寿命分别为(6.50±0.34)、(6.22±0.36)d,低于其他月份雌雄成虫的寿命。5、6月的高温会抑制种群的数量,是药剂防治的最佳时间。该研究为椰子织蛾的防治、预测预报等提供基础科学依据。     

Impact of incubator type on the yield of in vitro produced bovine blastocysts.

Because of suboptimal in vitro production of bovine blastocysts a new incubator model (Mini) was tested against the traditional (Heraeus). The difference between their properties seemed only to be the volume of the incubator space. No difference was noted between the CO2 or the temperature, but the data clearly showed a highly significant increase of the blastocyst rates, 6% versus 51% in the Heraeus and the Mini incubator, respectively, calculated as blastocysts per cleaved embryos. It was concluded that the incubator type or model may be a very important part of the in vitro production of bovine embryos, although we were not able to pin point specific causes for this difference.     

北京鸭蛋重与受精率、孵化率、蛋形指数及出雏重的关系

本研究将北京鸭Z1系种蛋分为小蛋组(82～92g)、中蛋组(92～105g)和大蛋组(106～124g),分别研究蛋重与受精率、孵化率、蛋形指数及初出重等性状的关系.结果表明蛋重对受精率的影响差异不显著(P＞0.05),但随着蛋重增大,受精率有增大的趋势;孵化率随蛋重的增加而显著减小(P＜0.05或P＜0.01);蛋重对蛋形指数的影响不显著(P＞0.05);雏鸭出生重受蛋重的正向影响差异极显著(P＜0.01).综合以上结果,本文得出北京鸭Z1系适宜孵化的蛋重范围是82～105g.     

The Effect of Melatonin on the Secretion of Progesterone in Sheep and on the Development of Ovine Embryos In Vitro

Two experiments were carried out in order to determine whether melatonin can improve secretion of progesterone in vivo, and its effect on embryonic development in vitro. In the first experiment, blood samples were collected from 5 ewes at 15 min intervals for 2 h at 7 and 10 days after withdrawal of progestagen pessaries. The first hour constituted a control period, which ended with an intravenous administration of 3 g/(kg bw)^0.75 melatonin. All the ewes on day 7 and three of the ewes on day 10 showed a progesterone response to melatonin challenge, defined as an increase in the plasma progesterone concentration in at least two consecutive samples during the post-treatment period above the mean+2SD of the values in the pre-treatment period. A paired t-test revealed a significant effect of melatonin on the overall plasma progesterone concentrations before and after the challenge, both on day 7 (pre, 0.61±0.11; post, 0.73±0.13 ng/ml; p<0.01) and day 10 (pre, 1.16±0.19; post, 1.30±0.20 ng/ml; p<0.05). Ninety-one thawed embryos (46 morulae and 45 blastocysts) were used in the second experiment, being cultured with or without 1 g/ml melatonin. If the embryos were blastocysts when the culture started, melatonin increased the percentage that had hatched after 24 h of culture (p<0.01), and there was a lower percentage of degenerated embryos at the end of the incubation period (p<0.05). It may be concluded that melatonin treatment in sheep can increase both fertility and prolificacy by improving luteal function and embryonic survival.     

牛体外受精胚的发育速度和染色体研究

利用不同个体的牛冷冻精液对屠宰场废弃牛卵巢内卵母细胞进行体外受精,对体外受精胚胎的发育速度和染色体的异常发生进行了研究。结果显示,冷冻精液A组体外受精48h后的卵裂率显著高于冷冻精液B组(P<0.05),2组之间的囊胚形成率差异显著(P<0.05);冷冻精液A体外受精后的胚胎发育速度显著快于冷冻精液B组(P<0.05);染色体分析结果表明,2组胚胎染色体异常发生率无显著差异,异常胚胎均表现为多倍体的发生率较高。     

Effect of estradiol‐17β during in vitro growth culture on the growth,maturation, cumulus expansion and development of porcine oocytes from early antral follicles

Growing porcine oocytes from early antral follicles can acquire meiotic and developmental competence under suitable culture conditions, but at lower rates compared to full‐grown oocytes. We postulated that estradiol‐17β (E₂) supported the acquisition of meiotic and developmental competence as well as cumulus‐expansion ability during growth culture. Growing oocytes from early antral follicles (1.2 to 1.5 mm in diameter) were grown in vitro for 5 days in a medium containing 0, 10^?7, 10^?6, 10^?5 or 10^?4 mol/L E₂; after in vitro maturation, 35, 58, 47, 74 and 49% of oocytes matured to metaphase II, 25, 79, 77, 90 and 97% acquired cumulus‐expansion ability, and 23, 54, 63, 89 and 64% were fully surrounded by cumulus cells, respectively. Following maturation, electro‐stimulation was applied to the oocytes grown with 10^?5 mol/L E₂. After 6 days of culture, in vitro‐grown oocytes developed to the blastocyst stage at a rate similar to that for full‐grown oocytes (31% and 40%, respectively). Therefore, we suggest that the use of E₂ during growth culture improves the meiotic and developmental competence of oocytes, cumulus‐expansion ability, and cumulus cell attachment to the oocytes.     

基于单细胞转录组测序技术筛选牛体内囊胚性别特异性基因

【目的】探究牛体内雌性和雄性囊胚在mRNA水平上的特异性差异,挖掘雌性和雄性囊胚发育差异相关候选基因。【方法】参考GenBank中牛牙釉质基因（AMEL）序列（AMELX基因,登录号：NM_001014984.1;AMELY基因,登录号：NM_174240.2）设计引物,以胚胎内细胞DNA为模板,采用巢式PCR扩增技术鉴定单个牛体内囊胚的性别。选用确定性别的单个雌性和雄性囊胚为试验材料,采用Smart-Seq2扩增技术构建单个胚胎测序文库,应用Illumina HiSeq Xten高通量测序平台对单个胚胎进行单细胞转录组测序（scRNA-Seq）,并进行了基因差异表达、GO功能和KEGG通路分析。【结果】通过巢式PCR扩增胚胎内细胞中的AMEL基因,确定了胚胎性别;基因表达分析筛选出两组之间差异表达基因（DEGs）6 160个,其中雌性特异性基因675个,雄性特异性基因305个;GO功能注释发现雌性特异性基因显著注释在核苷酸结合、信号转导调控、多细胞生物发育、细胞骨架等条目,雄性特异性基因显著注释在氧化磷酸化、线粒体、线粒体内膜、核糖体等条目;KEGG通路富集分析发现7条与雌性和雄性囊胚发育差异相关的通路,分别为代谢途径、糖酵解、磷酸戊糖途径、细胞衰老、氧化磷酸化、调节干细胞多能性的信号通路和Wnt信号通路;并利用GO和KEGG结果筛选出5个在牛体内囊胚期胚胎发育过程中具有直接或间接作用的基因：FBP1、GADD45G、FHL2、FOSB和WNT2B。【结论】牛体内雌性和雄性囊胚之间存在广泛的转录差异,性别特异性基因FBP1、GADD45G、FHL2、FOSB和WNT2B可能是直接或间接影响胚胎发育的关键基因。     

花尾榛鸡日粮中添加核黄素的研究

试验通过在种鸡和雏鸡日粮中添加不同剂量的核黄素,研究了核黄素对花尾榛鸡的营养作用。将16笼种鸡随机分为2组,每组8笼,Ⅰ组种鸡日粮中添加6.8mg/kg核黄素,Ⅱ组添加13.6mg/kg核黄素。结果表明:Ⅱ组的种蛋合格率、孵化率和健雏率分别比Ⅰ组提高了24.05%、8.2%和17.4%,差异极显著(P<0.01)。在雏鸡试验中,将80羽体重相近的健康雏鸡随机分为Ⅰ、Ⅱ、Ⅲ、Ⅳ组,第Ⅳ组为对照组,在基础日粮相同的基础上,其它3组分别喂以含核黄素3.6、7.2、14.4mg/kg的日粮,饲喂40d后观察各组生产性能,结果表明:各组试验雏榛鸡的生产性能均不同程度的高于对照组,其中Ⅱ、Ⅲ组与对照组存在显著差异(P<0.05),Ⅰ组与对照组差异不显著(P>0.05)。     

卵丘颗粒细胞核移植克隆猪的初步研究

经颗粒细胞核移植已成功获得克隆小鼠(Wakayamaetal.1998,Nature394:369)。在牛,卵丘颗粒细胞核移植胚胎也已经发育到囊胚期(Collasetal.1994,MolReprodDev38:264)。然而,目前在猪尚未见到有关颗粒细胞核移植成功的报道。为此,我们进行了颗粒细胞核移植培育克隆猪的研究。...     

收蚁袋使用效果试验调查

本文调查总结了不同收蚁方法及引蚁材料对孵化率的影响,结果以收蚁袋法和鹇桃叶引蚁法化率最高。