Cuckoldry rates in the Molly Miller (Scartella cristata; Blenniidae), a hole-nesting marine fish with alternative reproductive tactics

Microsatellite markers were developed and employed to assess genetic maternity and paternity of embryos in nest-tended clutches of the Molly Miller (Scartella cristata), a marine fish in which alternative reproductive tactics (ARTs) by males were recently described from behavioral and morphological evidence. Genetic data gathered for 1,536 surveyed progeny, from 23 barnacle-nest holes in a single Floridian population, indicate that on average about 5.5 females (range 3-9) contributed to the pool of progeny within a nest. With regard to paternity, the microsatellite data demonstrate that most of the surveyed nests (82.6%) contained at least some embryos that had not been sired by the nest-tending (bourgeois) male, and overall that 12.4% of offspring in the population had been sired via "stolen" fertilizations by other males. These are among the highest values of cuckoldry documented to date in nest-tending fishes, and they support and quantify the notion that the nest-parasitic ART is reproductively quite successful in this species despite what would otherwise seem to be highly defensible nesting sites (the restricted interior space of a barnacle shell). Our estimated cuckoldry rates in this population of the Molly Miller are compared to those previously reported for local populations in other nest-tending fish species, with results discussed in the context of ecological and behavioral variables that may influence relative frequencies of nest parasitism. © Springer-Verlag 2005

Effects of mesenchymal stromal cells versus serum on tendon healing in a controlled experimental trial in an equine model

Abstract Background Mesenchymal stromal cells (MSC) have shown promising results in the treatment of tendinopathy in equine medicine, making this therapeutic approach seem favorable for translation to human medicine. Having demonstrated that MSC engraft within the tendon lesions after local injection in an equine model, we hypothesized that they would improve tendon healing superior to serum injection alone. Methods Quadrilateral tendon lesions were induced in six horses by mechanical tissue disruption combined with collagenase application 3 weeks before treatment. Adipose-derived MSC suspended in serum or serum alone were then injected intralesionally. Clinical examinations, ultrasound and magnetic resonance imaging were performed over 24 weeks. Tendon biopsies for histological assessment were taken from the hindlimbs 3 weeks after treatment. Horses were sacrificed after 24 weeks and forelimb tendons were subjected to macroscopic and histological examination as well as analysis of musculoskeletal marker expression. Results Tendons injected with MSC showed a transient increase in inflammation and lesion size, as indicated by clinical and imaging parameters between week 3 and 6 (p < 0.05). Thereafter, symptoms decreased in both groups and, except that in MSC-treated tendons, mean lesion signal intensity as seen in T2w magnetic resonance imaging and cellularity as seen in the histology (p < 0.05) were lower, no major differences could be found at week 24. Conclusions These data suggest that MSC have influenced the inflammatory reaction in a way not described in tendinopathy studies before. However, at the endpoint of the current study, 24 weeks after treatment, no distinct improvement was observed in MSC-treated tendons compared to the serum-injected controls. Future studies are necessary to elucidate whether and under which conditions MSC are beneficial for tendon healing before translation into human medicine

Moulded cast compared with K-wire fixation after manipulation of an acute dorsally displaced distal radius fracture : the DRAFFT 2 RCT

Background: Patients with a displaced fracture of the distal radius are frequently offered surgical fixation. Manipulation of the fracture and moulded plaster casting is an alternative treatment that avoids metal implants, but evidence of its effectiveness is lacking. Objective: To compare functional outcomes, quality-of-life outcomes, complications and resource use among patients with a dorsally displaced fracture of the distal radius treated with manipulation and surgical fixation with Kirschner wires (K-wires) and those treated with manipulation and moulded cast. Design: Pragmatic, superiority, multicentre, randomised controlled trial with a health economic evaluation. Setting: A total of 36 orthopaedic trauma centres in the UK NHS. Participants: Patients (aged ≥ 16 years) treated for an acute dorsally displaced fracture of the distal radius were potentially eligible. Patients were excluded if their injury had occurred > 2 weeks previously, if the fracture was open, if it extended > 3 cm from the radiocarpal joint or if it required open reduction, or if the participant was unable to complete questionnaires. DOI: 10.3310/RLCF6332 Health Technology Assessment 2022 Vol. 26 No. 11 Copyright © 2022 Costa et al. This work was produced by Costa et al. under the terms of a commissioning contract issued by the Secretary of State for Health and Social Care. This is an Open Access publication distributed under the terms of the Creative Commons Attribution CC BY 4.0 licence, which permits unrestricted use, distribution, reproduction and adaption in any medium and for any purpose provided that it is properly attributed. See: https://creativecommons.org/licenses/by/4.0/. For attribution the title, original author(s), the publication source – NIHR Journals Library, and the DOI of the publication must be cited. vii Interventions: Participants were randomly assigned in theatre (1 : 1) to receive a moulded cast (i.e. the cast group) or surgical fixation with K-wires (i.e. the K-wire group) after fracture manipulation. Main outcome measures: The primary outcome measure was the Patient-Rated Wrist Evaluation score at 12 months, analysed on an intention-to-treat basis. Health-related quality of life was recorded using the EuroQol-5 Dimensions, five-level version, and resource use was recorded from a health and personal social care perspective. Results: Between January 2017 and March 2019, 500 participants (mean age 60 years, 83% women) were randomly allocated to receive a moulded cast (n = 255) or surgical fixation with K-wire (n = 245) following a manipulation of their fracture. A total of 395 (80%) participants were included in the primary analysis at 12 months. There was no difference in the Patient-Rated Wrist Evaluation score at 1 year post randomisation [cast group: n = 200, mean score 21.2 (standard deviation 23.1); K-wire group: n = 195, mean score 20.7 (standard deviation 22.3); adjusted mean difference –0.34 (95% confidence interval –4.33 to 3.66); p = 0.87]. A total of 33 (13%) participants in the cast group required surgical fixation for loss of fracture position in the first 6 weeks, compared with one participant in the K-wire group (odds ratio 0.02, 95% confidence interval 0.001 to 0.10). The base-case cost-effectiveness analysis showed that manipulation and surgical fixation with K-wires had a higher mean cost than manipulation and a moulded cast, despite similar mean effectiveness. The use of K-wires is unlikely to be cost-effective, and sensitivity analyses found this result to be robust. Limitations: Because the interventions were identifiable, neither patients nor clinicians could be blind to their treatment. Conclusions: Surgical fixation with K-wires was not found to be superior to moulded casting following manipulation of a dorsally displaced fracture of the distal radius, as measured by Patient-Rated Wrist Evaluation score. However, one in eight participants treated in a moulded cast required surgery for loss of fracture reduction in the first 6 weeks. After a successful closed reduction, clinicians may consider a moulded cast as a safe and cost-effective alternative to surgical fixation with K-wires. Future work: Further research should focus on optimal techniques for immobilisation and manipulation of this type of fracture, including optimal analgesia, and for rehabilitation of the patient after immobilisation. Trial registration: This trial is registered as ISRCTN11980540 and UKCRN Portfolio 208830. Funding: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 11. See the NIHR Journals Library website for further project information

Win-stay, lose-switch and public information strategies for patch fidelity of songbirds with rare extra-pair paternity

Determining where organisms breed and understanding why they breed in particular locations are fundamental biological questions with conservation implications. Breeding-site fidelity is common in migratory, territorial songbirds and is typically thought to occur following reproductive success with a social mate and success of nearby conspecifics. It is currently unknown if frequency of extra-pair paternity in a population influences use of information about reproductive success of nearby conspecifics for site fidelity decisions. We investigated patch fidelity of white-eyed vireos (Vireo griseus) based on reproductive success and quantified frequency of extra-pair paternity. We found support only for females making patch fidelity decisions following reproductive success with a social mate. Patch fidelity of males was not associated with reproductive success of nearby conspecifics, suggesting males may not use this information when extra-pair paternity is infrequent or the association is non-existent in this species

Massive Nest-Box Supplementation Boosts Fecundity, Survival and Even Immigration without Altering Mating and Reproductive Behaviour in a Rapidly Recovered Bird Population

Habitat restoration measures may result in artificially high breeding density, for instance when nest-boxes saturate the environment, which can negatively impact species' demography. Potential risks include changes in mating and reproductive behaviour such as increased extra-pair paternity, conspecific brood parasitism, and polygyny. Under particular cicumstances, these mechanisms may disrupt reproduction, with populations dragged into an extinction vortex. With the use of nuclear microsatellite markers, we investigated the occurrence of these potentially negative effects in a recovered population of a rare secondary cavity-nesting farmland bird of Central Europe, the hoopoe (Upupa epops). High intensity farming in the study area has resulted in a total eradication of cavity trees, depriving hoopoes from breeding sites. An intensive nest-box campaign rectified this problem, resulting in a spectacular population recovery within a few years only. There was some concern, however, that the new, high artificially-induced breeding density might alter hoopoe mating and reproductive behaviour. As the species underwent a serious demographic bottleneck in the 1970–1990s, we also used the microsatellite markers to reconstitute the demo-genetic history of the population, looking in particular for signs of genetic erosion. We found i) a low occurrence of extra-pair paternity, polygyny and conspecific brood parasitism, ii) a high level of neutral genetic diversity (mean number of alleles and expected heterozygosity per locus: 13.8 and 83%, respectively) and, iii) evidence for genetic connectivity through recent immigration of individuals from well differentiated populations. The recent increase in breeding density did thus not induce so far any noticeable detrimental changes in mating and reproductive behaviour. The demographic bottleneck undergone by the population in the 1970s-1990s was furthermore not accompanied by any significant drop in neutral genetic diversity. Finally, genetic data converged with a concomitant demographic study to evidence that immigration strongly contributed to local population recovery

Paternity analysis of pollen-mediated gene flow for Fraxinus excelsior L. in a chronically fragmented landscape

Paternity analysis based on microsatellite marker genotyping was used to infer contemporary genetic connectivity by pollen of three population remnants of the wind-pollinated, wind-dispersed tree Fraxinus excelsior, in a deforested Scottish landscape. By deterministically accounting for genotyping error and comparing a range of assignment methods, individual-based paternity assignments were used to derive population-level estimates of gene flow. Pollen immigration into a 300ha landscape represents between 43% and 68% of effective pollination, mostly depending on assignment method. Individual male reproductive success is unequal, with 31 of 48 trees fertilising one seed or more, but only three trees fertilising more than ten seeds. Spatial analysis suggests a fat-tailed pollen dispersal curve with 85% of detected pollination occurring within 100m, and 15% spreading between 300m and 1900m from the source. Identification of immigrating pollen sourced from two neighbouring remnants indicates further effective dispersal at 2900m. Pollen exchange among remnants is driven by population size rather than geographic distance, with larger remnants acting predominantly as pollen donors, and smaller remnants as pollen recipients. Enhanced wind dispersal of pollen in a barren landscape ensures that the seed produced within the catchment includes genetic material from a wide geographic area. However, gene flow estimates based on analysis of non-dispersed seeds were shown to underestimate realised gene immigration into the remnants by a factor of two suggesting that predictive landscape conservation requires integrated estimates of post-recruitment gene flow occurring via both pollen and seed

Breeding without Breeding: Is a Complete Pedigree Necessary for Efficient Breeding?

Complete pedigree information is a prerequisite for modern breeding and the ranking of parents and offspring for selection and deployment decisions. DNA fingerprinting and pedigree reconstruction can substitute for artificial matings, by allowing parentage delineation of naturally produced offspring. Here, we report on the efficacy of a breeding concept called “Breeding without Breeding” (BwB) that circumvents artificial matings, focusing instead on a subset of randomly sampled, maternally known but paternally unknown offspring to delineate their paternal parentage. We then generate the information needed to rank those offspring and their paternal parents, using a combination of complete (full-sib: FS) and incomplete (half-sib: HS) analyses of the constructed pedigrees. Using a random sample of wind-pollinated offspring from 15 females (seed donors), growing in a 41-parent western larch population, BwB is evaluated and compared to two commonly used testing methods that rely on either incomplete (maternal half-sib, open-pollinated: OP) or complete (FS) pedigree designs. BwB produced results superior to those from the incomplete design and virtually identical to those from the complete pedigree methods. The combined use of complete and incomplete pedigree information permitted evaluating all parents, both maternal and paternal, as well as all offspring, a result that could not have been accomplished with either the OP or FS methods alone. We also discuss the optimum experimental setting, in terms of the proportion of fingerprinted offspring, the size of the assembled maternal and paternal half-sib families, the role of external gene flow, and selfing, as well as the number of parents that could be realistically tested with BwB

Molecular Genetic Features of Polyploidization and Aneuploidization Reveal Unique Patterns for Genome Duplication in Diploid Malus

Polyploidization results in genome duplication and is an important step in evolution and speciation. The Malus genome confirmed that this genus was derived through auto-polyploidization, yet the genetic and meiotic mechanisms for polyploidization, particularly for aneuploidization, are unclear in this genus or other woody perennials. In fact the contribution of aneuploidization remains poorly understood throughout Plantae. We add to this knowledge by characterization of eupolyploidization and aneuploidization in 27,542 F1 seedlings from seven diploid Malus populations using cytology and microsatellite markers. We provide the first evidence that aneuploidy exceeds eupolyploidy in the diploid crosses, suggesting aneuploidization is a leading cause of genome duplication. Gametes from diploid Malus had a unique combinational pattern; ova preserved euploidy exclusively, while spermatozoa presented both euploidy and aneuploidy. All non-reduced gametes were genetically heterozygous, indicating first-division restitution was the exclusive mode for Malus eupolyploidization and aneuploidization. Chromosome segregation pattern among aneuploids was non-uniform, however, certain chromosomes were associated for aneuploidization. This study is the first to provide molecular evidence for the contribution of heterozygous non-reduced gametes to fitness in polyploids and aneuploids. Aneuploidization can increase, while eupolyploidization may decrease genetic diversity in their newly established populations. Auto-triploidization is important for speciation in the extant Malus. The features of Malus polyploidization confer genetic stability and diversity, and present heterozygosity, heterosis and adaptability for evolutionary selection. A protocol using co-dominant markers was proposed for accelerating apple triploid breeding program. A path was postulated for evolution of numerically odd basic chromosomes. The model for Malus derivation was considerably revised. Impacts of aneuploidization on speciation and evolution, and potential applications of aneuploids and polyploids in breeding and genetics for other species were evaluated in depth. This study greatly improves our understanding of evolution, speciation, and adaptation of the Malus genus, and provides strategies to exploit polyploidization in other species