中华绒螯蟹三种亲本规格子代的生长、肠道微生物菌群和代谢组学分析

中华绒螯蟹(Eriocheir sinensis)繁育亲蟹规格及其子代的生产性能是其产业上的热点问题。本研究应用个体生长测定法和代谢组学技术,研究了当前生产上3种主要育苗亲蟹规格（母本200~250g,父本300~350g;母本250~300g,父本350~400g;母本300g以上,父本400g以上）繁殖子代（规格A、规格B和规格C）的蜕壳与生长特性、肠道微生物菌群和肝胰腺代谢物的组成差异。结果发现：在2次个体蜕壳与生长测定中,规格C的生长性能优于其他两种规格,但3种规格子代相互间的蜕壳增重率、蜕壳间隔、肥满度、肝胰腺指数和肌肉指数均不存在显著差异。肠道菌群结果表明：α多样性指数均显示规格A低于其他两种规格,但3规格相互间无显著差异,而主坐标分析（PCoA）显示3种规格肠道菌群在属水平上存在显著差异。肝胰腺的代谢组学分析显示,规格A与B间共有100种差异代谢物,规格B与C间共有77种差异代谢物,规格A与C间共有79种差异代谢物。对差异肠道菌群和差异代谢物进行Pearson相关性分析发现：规格A的代谢物生物喋呤与副梭菌属呈显著正相关;规格B的代谢物N-乙酰-D-甘露糖胺分别与硝基螺菌门、硝化螺菌属呈显著负相关;规格C的代谢物四氢二吡啶甲酸盐与乳酸菌属呈显著负相关。本研究结果初步表明：不同亲蟹规格子代在生长性能、肠道微生物菌群和肝胰腺代谢物组成方面表现出一定差异。     

福建省主要土壤类型的镁素含量

通过测定9种土壤类型g4个土样,研究福建省主要土壤类型全镁和交换性镁(包括水溶性镁)的含量及其影响因素。结果表明我省土壤镁素含量较低。除盐土外,土壤全镁含量平均为0.33％,交换性镁含量0.82毫克当量/100克土。不同土壤类型全镁量高低顺序为:盐土>紫色土>水稻土>黄红壤、红壤>山地黄壤、赤红壤>山地草甸土>风沙土。交换性镁高低顺序为:盐土>水稻土>风沙土>紫色土>山地黄壤>黄红壤>赤红壤、红壤>山地草甸土。成土母质对土壤全镁和交换性镁含量有一定影响。土壤交换性镁与全镁含量呈极显著正相关,与土壤有机质含量呈极显著负相关,与土壤pH值呈显著正相关,与土壤粘粒(<0.001毫米)含量和阳离子交换量(CEC)呈正相关,但不显著。以土壤交换性镁饱和度10％作为足量指标进行划分:盐土和风沙土镁素充足,水稻土有75％样点土壤不缺镁,紫色土有50％样点土壤供镁充足,而红壤性土壤有80～90％样点土壤缺镁,山地草甸土镁素都是不足的。     

Effects of soybean isoflavones on reproductive parameters in Chinese mini-pig boars

Background: Soybean isoflavones are structurally similar to mammalian estrogens and therefore may act as estrogen agonists or antagonists. However, it has not been determined if they have any negative effects on reproductive parameters in male livestock. Therefore, the objective of this study was to evaluate the effects of soybean isoflavones on male reproduction using Chinese mini-pig boars as a model. Fifty Xiang boars were randomly divided into five groups and fed diets containing 0, 125, 250, or 500 ppm soybean isoflavones or 0.5 ppm diethylstilbestrol for 60 days. Results: Dietary supplementation with 250 ppm of soy isoflavones markedly increased the testis index (P<0.05), fructose content (P <0.05), and α-glycosidase content in testicular tissue (P<0.01), as well as increased the number of viable germ cells (P<0.01) and the level of Bcl-2 protein (P <0.01). However, 500 ppm of soybean isoflavones significantly reduced both testis and epididymis indexes (P<0.05) and lactate dehydrogenase levels (P<0.01), as well as reduced serum LH and testosterone levels (P<0.05). High levels of soybean isoflavones also increased malondialdehyde levels (P<0.05), as well as increased the numbers of early and late apoptotic germ cells (P<0.01) and the level of Bax proteins (P<0.05) in the testis. Conclusions: The results of this study indicate that consumption of soy isoflavones at dietary levels up to 250 ppm did not adversely affect reproductive parameters in Chinese mini-pig boars whereas higher levels of soy isoflavones may adversely affect male reproduction.     

雄性蜡皮蜥生殖器官的年周期变化

[目的]研究蜡皮蜥繁殖特征。[方法]每月购买5~6只雄性蜡皮蜥成体,解剖其生殖器官,并进行形态和组织学特征观察。[结果]蜡皮蜥雄性生殖器官组织结构具有一定年周期变化。睾丸重量和曲细精管管径,每年6月达峰值后迅速下降,8月降至最小值,9月开始增大,冬眠期发育缓慢,出蛰后继续增大;附睾和输精管的管径及管壁厚的年周期变化与睾丸重的变化情况基本相同;生精活动随生殖器官的周期性变化也发生相应的年周期变化。[结论]利用精巢重量的年周期变化来判定精子发生进程适用于蜥蜴类。     

小麦骨干亲本“周8425B”及其衍生品种的遗传解析和抗条锈病基因定位

 【目的】利用高密度分子标记解析了周8425B衍生品种的遗传结构,并鉴定其携带的抗条锈病基因。【方法】利用921个DArT（Diversity Arrays Technology）标记和83个SSR标记分析周8425B及其50份衍生品种（系）间的遗传结构和遗传区段传递,并利用关联分析定位抗条锈病基因。【结果】周8425B及其衍生品种的遗传相似性平均为67.6%,聚类分析结果与品种系谱来源基本一致。周8425B对其衍生一代、二代和三代的平均遗传贡献率分别为67.7%、63.6%和58.8%,在A、B和D基因组间遗传贡献率分别为 68.7%、62.0%和 59.4%。周8425B 对其衍生品种的21条染色体贡献率变幅为44.9%—70.9%,其中,对4A染色体贡献率最低,为44.8%,对1D染色体贡献率最高,达79.0%。利用DArT和SSR标记与成株期抗条锈鉴定结果进行关联分析,发现4个条锈病抗性位点（P＜0.01）,其中2个条锈病抗性位点QYr.caas-2BL和QYr.caas-7BL与已报道的抗条锈病基因Yr7和YrZH84在相同染色体区段,另一个抗性位点QYr.caas-1BL与抗叶锈基因LrZH84位置相同,推测该位点与LrZH84紧密连锁或者一因多效。在3A染色体长臂末端发现一个条锈病抗性位点QYr.caas-3AL,与标记wPt-0398关联,可能是一个新基因,能解释22.9%的表型变异。【结论】骨干亲本对衍生后代在基因组和染色体水平上的贡献率主要与重要基因遗传传递有关,衍生品种携带的4个抗条锈病基因均来自骨干亲本周8425B,这些抗性基因及其它优异基因将在黄淮冬麦区南片品种遗传改良中继续发挥重要作用。     

Assessment of maternal and parent of origin effects in genetic variation of economic traits in Iranian native fowl

ABSTRACT

1. The objective of the study was to investigate the influence of maternal and parent of origin effects (POE) on genetic variation of Iranian native fowl on economic traits.

2. Studied traits were body weights at birth (BW0), at eight (BW8) and 12 weeks of age (BW12), age (ASM) and weight at sexual maturity (WSM), egg number (EN) and average egg weight (AEW).

3. Several models, including additive, maternal additive genetics, permanent environmental effects and POE were compared using Wombat software. Bayesian Information Criterion (BIC) was used to identify the best model for each trait. The chance of reranking of birds between models was investigated using Spearman correlation and Wilcoxon rank test.

4. Based on the best model, direct heritability estimates for BW0, BW8, BW12, ASM, WSM, EN and AEW traits were 0.05, 0.21, 0.23, 0.30, 0.39, 0.22 and 0.38, respectively. Proportion of variance due to paternal POE for BW8 was 4% and proportion of variance due to maternal POE for BW12 was 5%.

5. Estimated maternal heritability for BW0 was 0.30 and for BW8 and BW12 were 0.00 and 0.01, respectively, which shows that maternal heritability was reduced by age.

6. Based on the results, considering POE for BW8 and BW12 and maternal genetic effects for BW0 improved the accuracy of estimations and avoid reranking of birds for these traits.     

银杏雄株种质资源遗传多样性研究

[目的]分析银杏雄株种质资源的遗传多样性,为其保存和育种创新奠定基础。[方法]采用改进的CTAB法提取来自11个省的银杏雄株叶片的基因组DNA,随机引物经初筛和复筛后用于RAPD扩增,并运用POPGENE软件分析银杏雄株种质资源的遗传多样性。[结果]从100多对随机引物中筛选出12对扩增带清晰、重复性和多态性好的引物,将其用于RAPD扩增和遗传多样性分析。利用筛选出的12对RAPD引物对40个样品进行PCR扩增,得到96条清晰条带,其中41条有多态性。银杏雄株种质资源的平均有效等位基因数为1.6440,平均基因多样度为0.3752,平均Shannon信息指数为0.5562。[结论]银杏雄株种质资源具有丰富的遗传多样性,对其有效保存和合理利用具有重要意义。     

核桃花芽形态分化研究进展

雌花芽形态分化起源芽内雏梢,于6月中旬至7月上旬(中短枝停长后4~10周)开始至次年开花,整个发育过程约需10个月,从芽的外部形态变化可直观地判断雌花芽分化时期;通过栽培措施调节使分化提前,增加芽内雏梢节数,提高雌花芽质量。雄花芽形态分化源于先年母芽雏梢分化期之后在叶腋出现的侧芽原基,4月上旬至翌年4月中旬性细胞形成历时约1年左右;雄花芽分化和开花散粉对树体养分消耗过大,影响雌花芽分化和果实发育,可采用疏雄、秋季施采果肥、春施速效肥等栽培措施减少影响。雌先型品种的雌花芽分化较雄先型品种开始分化早,在各个时期的分化上雌先型品种始终领先于雄先型品种,而雄先型品种在雄花芽分化的各个时期上领先于雌先型品种。     

大白菜CMS96不育系和保持系电镜观察

为了研究大白菜CMS96不育系花药败育机理,采用透射和扫描电镜,观察大白菜CMS96不育系和保持系的花药发育过程、花药和花粉表面结构。透射电镜结果表明,与保持系相比,在减数分裂期,大白菜CMS96不育系绒毡层与花药壁中层分开,不育系花粉母细胞皱缩,形状不规则,空隙较大,严重影响减数分裂正常进行;在单核小孢子时期,小孢子开始液泡化,直至成熟花粉期完全液泡化为空细胞,细胞壁严重萎缩,堆积在一起,最终花粉失去功能,导致败育。扫描电镜结果表明,大白菜CMS96不育系药室内的花粉畸形,花粉粒空瘪,表现为凹陷、扁平等形状,表面纹饰也呈多种不规则形状。花粉囊不开裂,没有花粉散出。初步认为,大白菜CMS96不育系花粉的败育从减数分裂开始到成熟花粉,伴随花粉发育整个过程。大白菜CMS96不育系药室内花粉粒虽具有花粉壁的结构,但扁平、空瘪,重叠堆积在药室壁上,失去了活力,无法散开。     

Effect of parity and progesterone priming on induction of reproductive function in Saanen goats by buck exposure

The response to the buck effect and the use of progesterone priming was studied in Saanen goats during the non-breeding season (April and May) in northern Mexico (26° N). Forty goats were assigned randomly in equal numbers (n = 10) to four treatment groups in a 2 × 2 factorial arrangement. Treatment consisted of two dosages of progesterone (P4) (0 or 5 mg) and two categories of goats, nulliparous and multiparous. Both parity groups were exposed to sexually active bucks previously exposed to a long-day photoperiodic scheme (16 h light day^− 1). All multiparous goats (20/20) displayed estrous behavior within the first 10 days of buck exposure, while 70% (14/20) of the nulliparous goats showed estrus (P > 0.05). During the first five days of buck exposure, the percentage of unprimed goats in estrus was 70% points lower than the primed goats, although progesterone priming did not affect the occurrence of estrus (90% vs 80%; P > 0.05) after 10 days of buck stimulus. The time to onset of estrus was four days shorter (P < 0.05) in P4-treated goats compared with controls. Pregnancy rate did not differ between primed and unprimed goats (80 vs 60%; P > 0.05), but this variable was higher (P < 0.05) in multiparous than nulliparous goats (95 vs 45%). It was concluded that it is possible to induce fertile estrus in Saanen goats during the non-breeding season in northern Mexico using sexually active bucks. The use of progesterone priming can accelerate the response of goats to the buck stimulus although it was ineffective in improving the pregnancy rate of goats. Additionally, a higher proportion of the multiparous goats got pregnant compared with the nulliparous goats induced to estrus by the buck stimulus.