Effects of pituitary-specific overexpression of FSHα/β on reproductive traits in transgenic boars

Background： Follicle-stimulating hormone（FSH） is a gonadotropin synthesized and secreted by the pituitary gland.FSH stimulates follicle development and maturation in females. It also plays an important role in spermatogenesis in males, including humans and mice. However, the effects of FSH on male pigs are largely unknown. In this study,we generated transgenic pigs to investigate the effects of FSHα/β overexpression on reproductive traits in boars.Results： After five transgenic F0 founders were crossed with wide-type pigs, 193 F_1 animals were obtained. Of these,96 were confirmed as transgenic. FSHα and FSHβ m RNAs were detected only in pituitary tissue. Transgenic boars exhibited significantly higher levels of FSHα and FSHβ m RNA, serum FSH, and serum testosterone, compared to ful-sib non-transgenic boars. Significant increases in testis weight, vas deferens diameter, seminiferous tubule diameter,and the number of Leydig cel s were observed, suggesting that the exogenous FSHα/β affects reproductive traits. Final y,transgenic and non-transgenic boars had similar growth performance and biochemical profiles.Conclusions： Pituitary-specific overexpression of FSHα/β genes is likely to impact reproductive traits positively, as indicated by enhancements in serum testosterone level, testis weight, the development of vas deferens, seminiferous tubules, and Leydig cells in transgenic boars. A high level of serum FSH induces secretion of serum testosterone,possibly by boosting the number of Leydig cells, which presumably increases the libido and the frequency of sexual activity in transgenic boars. Our study provides a preliminary foundation for the genetic improvement of reproductive traits in male pigs.

Association between UCP Gene Polymorphisms and Growth, Breeding Value of Growth and Reproductive Traits in Mazandaran Indigenous Chicken

The objective of this study was to estimate the allele and genotype frequencies of the UCP/Hha1 polymorphisms and to determine associations between these polymorphisms and growth traits, breeding value of growth and reproductive traits in Mazandaran Indigenous Chicken. To estimate breeding value of the reproductive traits, and phenotypic information of 18 successive generations of selection in breeding station of Mazandaran Indigenous Chicken (north of Iran), 190 birds were analyzed using a univariate animal model in ASREML procedure.. Genotyping of UCP gene polymorphism for all subjects was performed by the PCR–RFLP method. The evaluation of the association between this SNP with reproductive traits suggests a positive effect of TC genotype with age at first egg (ASM) compared with CC genotype. In addition, TC genotype was significantly associated with breeding value of age at first egg compared with CC genotype (P < 0.05). In conclusion, our results suggest that the TC genotype of the UCP gene is associated with age at sexual maturity (ASM) and breeding value of age at sexual maturity, and UCP polymorphisms may be used as DNA markers for selection in the breeding process of Mazandaran Indigenous Chicken.

Single Nucleotide Polymorphism of FSHβ Gene Associated with Reproductive Traits in Japanese Flounder (Paralichthys olivaceus)

Follicle stimulating hormone β (FSHβ) of Japanese flounder (Paralichthys olivaceus) plays a key role in the regulation of gonadal development.This study aimed to investigate molecular genetic characteristics of the FSHβ gene and elucidate the effects of single nucleotide polymorphisms (SNPs) of FSHβ on reproductive traits in Japanese flounder.We used polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) and sequencing of the FSHβ gene in 60 individuals.We identified only an SNP (T/C) in the coding region of exon3 of FSHβ.The SNP (T/C) did not lead to amino acid changes at the position 340 bp of FSHβ gene.Statistical analysis showed that the SNP was significantly associated with testosterone (T) level and gonadosomatic index (GSI) (P<0.05).Individuals with genotype TC of the SNP had significantly higher serum T levels and GSI (P<0.05) than that of genotype CC.Therefore, FSHβ gene could be a useful molecular marker in selection for prominent reproductive trait in Japanese Flounder.

Chemical reproductive traits of diploid Bombus terrestris males： Consequences on bumblebee conservation

The current bumblebee decline leads to inbreeding in populations that fosters a loss of allelic diversity and diploid male production. As diploid males are viable and their offspring are sterile, bumblebee populations can quickly fall in a vortex of extinction. In this article, we investigate for the first time a potential premating mechanism through a major chemical reproductive trait （male cephalic labial gland secretions） that could prevent monandrous virgin queens from mating with diploid males. We focus our study on the cephalic labial gland secretions of diploid and haploid males ofBombus terrestris （L.）. Contrary to initial expectations, our results do not show any significant differentiation of cephalic labial gland secretions between diploid and haploid specimens. Queens seem therefore to be unable to avoid mating with diploid males based on their compositions of cephalic labial gland secretions. This suggests that the vortex of extinction of diploid males could not be stopped through premating avoidance based on the cephalic labial gland secretions but other mechanisms could avoid mating between diploid males and queens.

Effects of the TLR4 transgene on reproductive traits and DNA methylation pattern of oocytes in ewes

This study was conducted to systematically assess the reproductive performance of transgenic TLR4 ewes.In the TLR4 transgenic founders(F_(0))and their positive offspring(F_(1)),hematological and reproductive parameters and the global DNA methylation level in oocytes at various stages were analyzed.The values of the physiological and biochemical parameters determined from the blood samples did not differ significantly between the transgenic and wild-type ewes.Moreover,the transgenic ewes showed reproductive traits similar to the wildtype ewes.These traits included characteristics of puberty,the estrus cycle,estrus duration,gestation,the pregnancy rate and the superovulation response.Additionally,no significant differences were found between transgenic and wild-type ewes in the DNA methylation level of the oocytes at various stages.In summary,the preliminary evidence presented in this paper demonstrates that the presence of the TLR4 transgene did not affect the reproductive performance in sheep.

Studying Some Brain and Ovarian Morphological Traits in Diaglena spatulata Female Frogs Thriving in Conserved and Perturbed Habitats:A Preliminary Report and Its Implications for Amphibian Survival and Continuity

Amphibians are thought to be highly susceptible to perturbed environments. However, recent studies show that many of them are successful inhabitants of disturbed, fragmented habitats. The source of this resilience is yet unclear, but it may be the byproduct of having a robust phenotype and/or the result of phenotypic plasticity. We then assessed the contribution of each by evaluating cytological features of two brain nuclei that modulate reproductive behavior and of the ovary, using female specimens of the frog Diaglena spatulata prospering in conserved and disturbed areas of a tropical dry forest. Our results in the brain show that the medial amygdala, but not the preoptic area, had a reduced size in frogs collected in disturbed forests compared to specimens collected in conserved forests. Both brain nuclei displayed, however, neurons with a reduced size in frogs captured in disturbed forest patches. In contrast, ovarian cytological features were similar between groups. Our preliminary results lead us to propose that Diaglena spatulata female specimens might combine robust ovary and plastic brain’s phenotypic traits to confront disturbed environments. This, however, is still a working hypothetical framework that needs to be experimentally confirmed.

Population structure and reproductive biology of the mysid Nanomysis siamensis(Crustacea:Mysida)in Songkhla Lagoon system,southern Thailand

Songkhla Lagoon in southern Thailand is a large lagoon with brackish water where the mysid Nanomysis siamensis inhabit.N.siamensis has long been the dominant mysid species in this lagoon.However,nothing is known about the biology and ecology of N.siamensis.Here for the first time,we provide information about its demographic structure and reproductive biology in the Songkhla Lagoon system.We conducted monthly sampling from June 2017 to June 2018 at five stations in Thale Sap and seven stations in Thale Sap Songkhla.Individuals were classified into six categories.The monthly mean density ranged 8.44-807.33 inds./100 m^(2) in Thale Sap and 8.81-434.44 inds./100 m^(2) in Thale Sap Songkhla.The peak occurrence of this species was in May 2018 in Thale Sap.The population composition was as follows:juvenile 10.13%,immature males 13.45%,immature females 10.54%,mature males 26.19%,mature females 21.63%and ovigerous females 18.05%.The proportion of ovigerous females was statistically significant and brooding females in the nauplioid stage were more dominant than embryonic phase and post-nauplioid stages.Brood size varied from 1 to 17,the embryo diameter ranging from 0.2 to 0.4 mm and the lengths of the larvae ranged from 0.5 to 1.0 mm.There was a positive correlation between brood size and brood length with ovigerous female body length.Overall,mature males were predominant over the five population composition types,and reproduction in N.siamensis was observed every month.

Association Between the 313 bp Indel in Porcine POU1F1 Gene and Reproduction Traits

The study aims to analyze the distribution of the 313 bp indel （insertion/deletion termed as indel） in first intron of POU1F1 and it＇s association with reproduction traits in Sutai pigs by using the PCR-DSCP technique. The results showed that in this commercial pig population, the frequency of allele A was 0.6371, B was 0.3629; the genotype frequency of AA was 0.4516, AB was 0.3710, BB was 0.1774, and the Z2 test showed that the allele frequencies were in Hardy-Weinberg equilibrium. The SPSS GLM procedure was used to identify the association of the 313 bp indel with reproductive traits. In Sutai pigs, the pigs with AA genotype represented higher value in all reproduction traits, except for higher survival rate of piglets at weaning. Higher weaning weight was significantly associated with AA genotype pigs and higher survival rate of piglets at weaning was significantly associated with BB genotype （P〈0.05）, but no significant differences in other reproduction traits among genotypes were found （P〉0.05）; the P value of different traits affected by fixed factors were not significant as well （P〉0.05）. The result indicated that although this 313 bp indel was significantly associated with the weaning weight and survival rate at weaning, no any association with major reproduction traits was observed in Sutai pigs.

Signatures of positive selection for local adaptation of African native cattle populations:A review

Cattle are central to the lives and diverse cultures of African people.It has played a crucial role in providing valuable protein for billions of households and sources of income and employment for producers and other actors in the livestock value chains.The long-term natural selection of African cattle typically signals signatures in the genome,contributes to high genetic differentiations across breeds.This has enabled them to develop unique adaptive traits to cope with inadequate feed supply,high temperatures,high internal and external parasites,and diseases.However,these unique cattle genetic resources are threatened by indiscriminate cross-breeding,breed replacements with exotic cosmopolitan breeds,and climate change pressures.Although there are no functional genomics studies,recent advancements in genotyping and sequencing technologies have identified and annotated limited functional genes and causal variants associated with unique adaptive and economical traits of African cattle populations.These genome-wide variants serve as candidates for breed improvement and support conservation efforts for endangered cattle breeds against future climate changes.Therefore,this review plans to collate comprehensive information on the identified selection footprints to support genomic studies in African cattle to confirm the validity of the results and provide a framework for further genetic association and QTL fine mapping studies.

Impact of brine acidification on hatchability, survival and reproduction of Artemia parthenogenetica and Artemia franciscana in salt ponds, Bohai Bay, China

We studied the effect of pH （pH 5, 6, 7 and 8） on the hatching percentage, survival and reproduction of Artemia strains in Bohai Bay salt ponds. Strains included parthenogenetic Artemia from Bohai Bay （BHB）, Artemiafranciscana from San Francisco Bay, and A. franciscana artificially produced in salt ponds in Vietnam. The latter was included as a potential inoculum for biological management of salt ponds. The hatching percentage of cysts after 24 h and the survival rate of the tested Artemia strains were significantly reduced when exposed to a culture medium at pH 5 for 18 d （P〈0.05）. The tolerance of Artemia to 48 h acid exposure varied with developmental stage, increasing in the following order： juvenile, nauplii, pre-adult, with maximum tolerance in adults. All strains of Artemia tested could not reproduce at pH 5. At pH levels from pH 6-8, a higher pH generally resulted in a shorter brood interval and enhanced ovoviviparity. Hence, we suggest that brine acidification has a negative impact on Artemia populations in the Bohai Bay saltworks. Inoculation of Artemia with either local parthenogenetic Artemia or exotic A. franeiscana should be feasible at pH 7-8.

The Breeding Ecology of a Critically Endangered Salamander,Hynobius amjiensis(Caudata：Hynobiidae),Endemic to Eastern China

Hynobius amjiensis is a critically endangered salamander species（IUCN Red List） endemic to eastern China. It currently has three known populations： one in Longwangshan, Zhejiang Province（type locality）, and two in Qingliangfeng between Anhui and Zhejiang Provinces. We examined the relatively unstudied breeding ecology of this species in the field and at laboratory from March 2007 to May 2014. Adult males and females were year-round terrestrial, except for the February–April breeding season. During this period, we captured only a total of 16 breeding adults（11 males and 5 females）. As few as 100 breeding females were estimated based on the number of egg sacs observed since 2007. This number was significantly reduced from the estimated number between 1992 and 1998. Males（mean total length = 16.21 cm, mean body mass = 18.8 g） were slightly smaller than females（16.51 cm, 19.2 g）. Size of breeding pools ranged from 0.2 m-2 to 1.2 m-2（0.1–1.2 m depths）. Each female deposits a pair of egg sacs by attaching the adhesive tips of the sacs to aquatic plants or dead twigs. Fifteen pairs of egg sacs had an average length of 28.6 cm and a diameter of 3.3 cm. On average, each egg sac contained 75 eggs with a diameter of 0.3 cm. Our field survey revealed that H. amjiensis used oviposition sites in small, cool, and weakly acidic pools at high elevations（1 300–1 600 m） where peat moss was abundant. Reduction in wetland size and disappearance of suitable breeding pools suggest that this salamander species is under threat of extinction, particularly at Longwangshan, where 5 of the 9 breeding pools have either dried up or disappeared. Combined size of the remaining 4 pools is less than 2 m-2. We urge immediate implementation of more effective conservation measures and suggest that preservation priority should be given to habitat that contains suitable breeding pools.

Patterns of plant sexual systems in subtropical evergreen broad-leaved forests in Ailao Mountains, SW China

Aims Sexual systems influence many components of the ecology and evolution of plant populations and have rarely been documented in subtropical evergreen broad-leaved forests(SEBLF).Here we report frequency distribution and ecological correlates of plant sexual systems in SEBLF at Ailao Mountains,and compare our results with that of tropical and cool temperate forests.Methods We examine the sexual systems of 703 species of woody angiosperms belonging to 103 families and 296 genera based on a comprehensive survey of SEBLF at Ailao Mountains Natural Reserve.Information of plant sexual systems and ecological traits were mainly based on published literatures and specimens as well as our field observations.The associations between plant sexual system and ecological traits were assessed with chi-square tests.Important findings Among these species,60.2%were hermaphroditic,15.8%were monoecious and 24.0%were dioecious.The percentage of dioecious sexual system among tree species(22.2%)in SEBLF was comparable to those of tropical tree floras,but much higher than those of temperate forests at North America.The percentage of monoecious sexual system among tree species(30.1%)in SEBLF was higher than that of tropical tree floras,but much lower than those of temperate forests at North America.Monoecy was significantly associated with the tree growth form and was relatively common in temperate genera.Dioecy was significantly associated with fleshy fruits and monoecy was significantly associated with dry fruit type in SEBLF.The high percentage of diclinous sexual systems(monoecy and dioecy)in SEBLF may be associated with the origin of the flora and the prevalence of relatively small inconspicuous flowers of the forests in the Oriental Region.

Phylogenetic and climatic constraints drive flowering phenological patterns in a subtropical nature reserve

Aims Exploring flowering patterns and detecting processes are essential when probing into the nature of reproductive traits during the life history and the interactions among different evolutionary clades.such patterns are believed to be influenced by many factors,but quantifying these impacts at the community-level remains poorly understood.Methods We investigated the flowering patterns based on long-term her-barium records in a given area from subtropical forest regions in southern China.We obtained 5258 herbarium voucher specimens collected from the Dinghushan National Nature reserve(DNNr)belonging to 166 families,943 genera and 2059 species and exam-ined the month when each species was flowering during the period 1920-2007.Important Findings The results showed that plants flowered sequentially almost through-out the whole year,showing the characteristics of subtropical evergreen broad-leaved forests.Flowering spectrums of the entire flora and the four life forms exhibited a clear unimodality that is probably typical of subtropical forest communities.Flowering pat-terns of the DNNr were positively correlated with mean rainfall,mean air temperature and mean sunshine duration.median flowering dates of the 38 large species-rich families ranged from early april to late august;25 families exhibited significant unimodal distribution patterns,whereas the remaining families were unclear or bimodal.median flowering dates of the 10 most species-rich genera ranged from middle may to later July.While the results are consist-ent with climatic factors playing a general role in flowering patterns,median flowering dates varied significantly among species-rich families and genera,suggesting that phylogenies could provide spe-cific constraints in subtropical forests.