离乳大鼠假性性早熟模型的建立及对雌活性物质的应答

以雌激素含量明确的避孕药物作诱导剂观察了其对离乳Wistsar大鼠性成熟的影响,结果显示在给予避孕药后体重、乳腺、阴门、阴道上皮细胞、卵巢、子宫均发生类似人体假性性早熟变化,而肾上腺、脑垂体、甲状腺等与对照组比较均未见明显差异。     

甘蓝型油菜RPD3/HDA1基因家族鉴定及早熟相关基因挖掘

该研究运用生物信息学方法鉴定甘蓝型油菜RPD3/HDA1基因家族,检测了其在‘黔油早2号’和‘中双11’中的表达水平及2个品种在低温(4℃)和ABA胁迫下该家族基因的表达特征,以探讨RPD3/HDA1基因在甘蓝型油菜中的潜在功能,为早熟油菜抗逆性遗传改良提供理论基础和候选基因。结果表明:(1)在甘蓝型油菜全基因组中共鉴定到28个RPD3/HDA1基因,将其命名为BnHDA1~BnHDA28,聚类为4个亚家族,同一亚家族成员的基因结构较为相似;在该基因家族中共检测到16对复制基因,均为片段重复。(2)顺式作用元件预测统计中共发现675个元件与植物激素、环境胁迫和光响应有关。(3)qRT-PCR分析显示,RPD3/HDA1基因在‘黔油早2号’中的表达量均高于‘中双11’;低温胁迫下,‘黔油早2号’和‘中双11’中RPD3/HDA1基因呈差异表达,与‘中双11’相比,RPD3/HDA1基因在‘黔油早2号’中的下调幅度较大;ABA处理后,RPD3/HDA1基因在2个品种中表达模式不一致,‘黔油早2号’中大部分RPD3/HDA1基因表达量较‘中双11’下调幅度小。研究认为,RPD3/HDA1基因可能在油菜开花中发挥调节作用,而且可能通过激素信号通路和防御信号通路参与油菜的生长发育和防御反应的调节。     

早熟砂梨ISSR-PCR反应体系的建立与优化

以我国南方主栽的早熟砂梨品种‘翠冠’Pyrus pyrifolia ‘Cuiguan’为材料,对ISSR技术体系中的模板DNA浓度、Taq DNA聚合酶用量、引物浓度、dNTP浓度、Mg2+浓度、退火温度、PCR循环数等7个主要因素进行优化和筛选,建立了适合早熟砂梨的ISSR-PCR反应体系。最终反应体系为20 μL体系中10×PCR buffer（不含Mg2+）2 μL,模板DNA浓度60 ng,TaqDNA聚合酶0.75 U,引物浓度1 μmol/L,dNTP浓度90 μmol/L,Mg2+浓度2.25 mmol/L。扩增程序为：预变性94 ℃ 5 min,变性94 ℃ 45 s,退火45 s,72 ℃延伸1 min,共42个循环,然后72 ℃再延伸10 min,4 ℃保存,用1.5%琼脂糖凝胶电泳检测多态性。     

Genetic relationship between growth and reproductive traits in Nellore cattle

The objective of this study was to evaluate the genetic relationship between postweaning weight gain (PWG), heifer pregnancy (HP), scrotal circumference (SC) at 18 months of age, stayability at 6 years of age (STAY) and finishing visual score at 18 months of age (PREC), and to determine the potential of these traits as selection criteria for the genetic improvement of growth and reproduction in Nellore cattle. The HP was defined as the observation that a heifer conceived and remained pregnant, which was assessed by rectal palpation at 60 days. The STAY was defined as whether or not a cow calved every year up to the age of 6 years, given that she was provided the opportunity to breed. The Bayesian linear-threshold analysis via the Gibbs sampler was used to estimate the variance and covariance components applying a multitrait model. Posterior mean estimates of direct heritability were 0.15 ± 0.00, 0.42 ± 0.02, 0.49 ± 0.01, 0.11 ± 0.01 and 0.19 ± 0.00 for PWG, HP, SC, STAY and PREC, respectively. The genetic correlations between traits ranged from 0.17 to 0.62. The traits studied generally have potential for use as selection criteria in genetic breeding programs. The genetic correlations between all traits show that selection for one of these traits does not imply the loss of the others.     

Comparison among three approaches for evaluation of sexual precocity in Nellore cattle

Restricted breeding seasons used in beef cattle produce censored data for reproduction traits measured in regard to these seasons. To analyze these data, adequate methods must be used. The objective of this paper was to compare three approaches aiming to evaluate sexual precocity in Nellore cattle. The final data set contained 6699 records of age at first conception (AFC14) (in days) and of heifer pregnancy (HP14) (binary) obtained from females exposed to the bulls for the first time at about 14 months of age. Records of females that did not calve in the following year after being exposed to a sire were considered censored (77.5% of total). The models used to obtain genetic parameters and expected progeny differences (EPDs) were a Weibull mixed and a censored linear model for AFC14 and threshold model for HP14. The mean heritabilities obtained were 0.76 and 0.44, respectively, for survival and censored linear models (for AFC14), and 0.58 for HP14. Ranking and Pearson correlations varied (in absolute values) from 0.54 to 0.99 (considering different percentages of sires selected), indicating moderate changes in the classification. Considering survival analysis as the best selection criterion (that would result in the best response to selection), it was observed that selection for HP14 would lead to a more significant decrease in selection response if compared with selection for AFC14 analysed by censored linear model, from which results were very similar to the survival analysis.     

知柏地黄丸治疗对中枢性性早熟女童卵巢容积，卵泡直径及第二性征发育的影响

摘要 目的：探究知柏地黄丸治疗对中枢性性早熟（ICPP）女童卵巢容积、卵泡直径及第二性征发育的影响。方法：选取2019年2月~2021年2月于本院就诊的86例ICPP女童,随机分为对照组（n=43）和观察组（n=43）,对照组给予醋酸曲普瑞林,观察组在对照组基础上给予知柏地黄丸。比较两组临床疗效、子宫容积、卵巢容积和卵泡直径、性激素水平[促卵泡激素（FSH）、雌二醇（E₂）及促黄体激素（LH）]、骨代谢指标水平[Ⅰ型胶原氨基端肽（P1NP）、骨钙素N端中分子片段（N-MID）、Ⅰ型胶原羧基端肽交联（β-CTX）]及不良反应。结果：治疗后与对照组相比,观察组总有效率明显较高（P<0.05）,子宫容积、卵巢容积和卵泡直径均明显较小（P<0.05）,FSH、E₂、LH、P1NP、N-MID及β-CTX水平均明显较低（P<0.05）;两组不良反应总发生率无差异（P>0.05）。结论：知柏地黄丸治疗ICPP患儿具有较好的临床疗效,可减小卵巢、子宫的提前变化,降低性激素水平,改善骨代谢指标水平,安全性较好。     

中华绒螯蟹一龄早熟和二龄成熟家系生长规律的比较研究

中华绒螯蟹(Eridcheir sinensis)1龄性早熟是扣蟹养殖过程中的一个重要问题,尚不清楚1龄性早熟和2龄正常性成熟后代的生长发育规律是否存在差异,本研究通过构建1龄性早熟和正常性成熟中华绒螯蟹家系,综合比较了单养条件下两种家系子一代(以下简称早熟F1和正常F1)在扣蟹和成蟹阶段的生长蜕壳规律、雌蟹腹脐覆盖腹甲宽度比例、成熟后的性腺指数(GSI)和肝胰腺指数(HSI)。结果显示:(1)早熟F1雄体在第1、2次和第7、8次蜕壳后的体重显著大于正常F1雄体(P0.05);而早熟F1雌体在第1~5次和第7次蜕壳后的体重显著大于正常F1雌体(P0.05);(2)第1和2次蜕壳后早熟F1的增重率较高,正常F1在第3~8次蜕壳后的增重率略高于早熟F1,两群体在扣蟹阶段的特定生长率均呈下降趋势,且正常F1高于早熟F1,其中雌雄个体在第3~4次蜕壳后的特定生长率均存在显著差异(P0.05);(3)早熟F1在第1~5次蜕壳间隔较长,而第6~8次蜕壳间隔较短;两种家系在扣蟹养殖阶段蜕壳4~6次,成蟹养殖阶段蜕壳2~4次,其中早熟F1在扣蟹阶段的平均蜕壳次数低于正常F1,而在成蟹阶段的平均蜕壳次数高于正常F1;(4)早熟F1腹脐覆盖腹甲宽度比例一直高于正常F1,但二者无显著差异(P0.05);(5)无论雌体还是雄体,早熟F1和正常F1的性腺指数和肝胰腺指数均无显著差异,单养条件下性腺均可发育成熟(P0.05)。综上,单养条件下,中华绒螯蟹早熟F1和正常F1的生长模式存在显著差异,两者都可以完成生殖蜕壳和性腺发育成熟,这为今后深入研究中华绒螯蟹个体生物学提供了理论依据和参考资料。     

Association Between Sexual Precocity and Alleles of KISS-1 and GPR54 Genes in Goats

KISS-1 and GPR54 were regarded as key regulators for the puberty onset and fundamental gatekeepers of sexual maturation in mammals. To explore the possible association between variations in KISS-1 and GPR54 with sexual precocity, mutation screening of exon 1 of KISS-1 and exon 1, exon 3, and partial exon 5 of GPR54 was performed in a sexual precocious breed (Jining Grey goats) and sexual late-maturing breeds (Inner Mongolia Cashmere, Angora, and Boer goats) by PCR-SSCP. The results showed that five novel mutations were identified in exon 1 and partial exon 5 of GPR54 including C96 T, T173C, G176A, G825A, and C981 T. The Jining Grey goats with genotype BB or AB had 1.07 (P < 0.05) or 0.40 (P < 0.05) kids more than those with AA. The Jining Grey goats with genotype DD or CD had 1.80 (P < 0.05) or 0.55 (P < 0.05) kids more than CC, respectively. The present study preliminarily showed an association between alleles B and D of GPR54 with high litter size and sexual precocity in Jining Grey goats.     

Juvenile Precocity and Maintenance of Juvenile Features in the Males of the Pentastome Kiricephalus pattoni (Stephens, 1908) Sambon, 1922

Summary

Male nymphs of the pentastome Kiricephalus pattoni become sexually mature in the second intermediate host, the water snake Tropidonotus piscator. Pairing of male and female nymphs, and sperm transfer, occur at the same stage. Males (but not females) retain nymphal characters within the definitive host, the rat snake Ptyas mucosus.