Number Of Progeny Research Articles

Dedifferentiation‐derived neural stem cells exhibit perturbed temporal progression

Dedifferentiation is the reversion of mature cells to a stem cell‐like fate, whereby gene expression programs are altered and genes associated with multipotency are (re)expressed. Misexpression of multipotency factors and pathways causes the formation of ectopic neural stem cells (NSCs). Whether dedifferentiated NSCs faithfully produce the correct number and types of progeny, or undergo timely terminal differentiation, has not been assessed. Here, we show that ectopic NSCs induced via bHLH transcription factor Deadpan (Dpn) expression fail to undergo appropriate temporal progression by constantly expressing mid‐temporal transcription factor(tTF), Sloppy‐paired 1/2 (Slp). Consequently, this resulted in impaired terminal differenation and generated an excess of Twin of eyeless (Toy)‐positive neurons at the expense of Reversed polarity (Repo)‐positive glial cells. Preference for a mid‐temporal fate in these ectopic NSCs is concordant with an enriched binding of Dpn at mid‐tTF loci and a depletion of Dpn binding at early‐ and late‐tTF loci. Retriggering the temporal series via manipulation of the temporal series or cell cycle is sufficient to reinstate neuronal diversity and timely termination.

Characterization of the dual role of Plasmodium falciparum DNA methyltransferase in regulating transcription and translation.

DNA modifications are critical in fine-tuning the biological processes in model organisms. However, the presence of cytosine methylation (5mC) and the function of the putative DNA methyltransferase, PfDNMT2, in the human malaria pathogen, Plasmodium falciparum, remain controversial. Here, we revisited the 5mC in the parasite genome and the function of PfDNMT2. Low levels of genomic 5mC (0.1-0.2%) during asexual development were identified using a sensitive mass spectrometry procedure. Native PfDNMT2 displayed substantial DNA methylation activities, and disruption or overexpression of PfDNMT2 resulted in reduced or elevated genomic 5mC levels, respectively. PfDNMT2 disruption led to an increased proliferation phenotype, with the parasites having an extended schizont stage and producing a higher number of progenies. Consistent with PfDNMT2's interaction with an AP2 domain-containing transcription factor, transcriptomic analyses revealed that PfDNMT2 disruption led to a drastic alteration in the expression of many genes, some of which provided the molecular basis of enhanced proliferation after PfDNMT2 disruption. Furthermore, levels of tRNAAsp and its methylation rate at position C38, and the translation of a reporter containing an aspartate repeat were significantly reduced after PfDNMT2 disruption, while the levels of tRNAAsp and its C38 methylation were restored after complementation of PfDNMT2. Our study sheds new light on the dual function of PfDNMT2 during P. falciparum asexual development.

Microsporogenesis in the triploid hybrid ‘Beilinxiongzhu 1#’ and detection of primary trisomy in 2x × 3 × Populus hybrids

BackgroundPrimary trisomy is a powerful genetic tool in plants. However, trisomy has not been detected in Populus as a model system for tree and woody perennial plant biology.ResultsIn the present study, a backcross between Populus alba × Populus glandulosa ‘YXY 7#’ (2n = 2x = 38) and the triploid hybrid ‘Beilinxiongzhu 1#’ (2n = 3x = 57) based on the observation of microsporogenesis and an evaluation of the variations in pollen was conducted to create primary trisomy. Many abnormalities, such as premature migration of chromosomes, lagging of chromosomes, chromosome bridges, asymmetric separation, micronuclei, and premature cytokinesis, have been detected during meiosis of the triploid hybrid clone ‘Beilinxiongzhu 1#’. However, these abnormal behaviors did not result in completely aborted pollen. The pollen diameter of the triploid hybrid clone ‘Beilinxiongzhu 1#’ is bimodally distributed, which was similar to the chromosomal number of the backcross progeny. A total of 393 progeny were generated. We provide a protocol for determining the number of chromosomes in aneuploid progeny, and 19 distinct simple sequence repeat (SSR) primer pairs covering the entire Populus genome were developed. Primary trisomy 11 and trisomy 17 were detected in the 2x × 3 x hybrid using the SSR molecular markers and counting of somatic chromosomes.ConclusionsNineteen distinct SSR primer pairs for determining chromosomal number in aneuploid individuals were developed, and two Populus trisomies were detected from 2x × 3 x hybrids by SSR markers and somatic chromosome counting. Our findings provide a powerful genetic tool to reveal the function of genes in Populus.

Evaluation of three organophosphorus insecticides alone and in combination with inert dusts for the control of Trogoderma granarium Everts (Coleoptera: Dermestidae)

Management of Trogoderma granarium with insecticides alone is difficult due to its high tolerance to commonly used insecticides. In the present study, three organophosphorus insecticides (OPs), chlorpyrifos-methyl (CH), pirimiphos-methyl (PI) and malathion (MA) were evaluated alone or in binary blends with diatomaceous earth (DE), kaolin (KA) and zeolite (ZE) against T. granarium on stored wheat. The following concentrations were used: CH (2.5 and 5 ppm), PI (5 and 10 ppm), MA (4 and 8 ppm) and inert dusts (IDs) (500 and 1000 ppm). The number of dead larvae was counted 1, 2 and 3 weeks after exposure. Progeny (F1 and F2) was recorded 30 and 80 days after exposure, respectively. The wheat grain damage was measured at the end of experiments (80 days). The results revealed that the mortality of khapra beetle larvae was higher in all binary mixture treatments of OPs and IDs than individual ones. The mixtures of CH with IDs caused complete larval mortality at application rate (5 ppm). The binary mixtures of PI or MA with IDs induced strong mortality of T. granarium larvae (>82%). Furthermore, the results indicate that the combination of CH and inert dusts or PI with ZE at the highest rate completely suppressed F1 and F2 progeny after 80 days of treatment. The lowest number of F1 and F2 progeny was recorded in wheat treated with MA (8.0 ppm) + DE (1000 ppm) with 1.0 and 1.6 adults/50g, respectively. The mixtures of OPs and IDs at the highest tested rate protected wheat grains against damage caused by insect for 80 days. The findings of the present study indicate that the binary mixtures of OPs, especially CH and IDs are highly effective for the control of khapra beetle and could be implemented in the management of this destructive invasive insect.

Performance of two egg parasitoids of brown marmorated stink bug before and after cold storage.

Introduction: The genus Trissolcus includes a number of egg parasitoids that are known to contribute to the control of Halyomorpha halys. The number of progenies, particularly females, is important for the efficient mass rearing of species used in augmentative biological control programs. Cold storage is an important technique for extending the shelf life of natural enemies used in such programs. Methods: We assessed how fecundity, sex ratio, lifespan, and the number of hosts parasitized within 24h were affected by host density for T. japonicus and T. cultratus when offered fresh H. halys eggs and how these parameters were affected if adult parasitoids were first placed in cold storage (11°C in the dark) for 19weeks before being used for propagation. Results: The fecundity were 110.2 and 84.2 offspring emerged at 25°C, for parasitoids not placed in cold storage; among the offspring that emerged, 82.6% and 85.6% were female for T. japonicus and T. cultratus, respectively. If first placed in cold storage, T. japonicus and T. cultratus produced 35.1 and 24.6 offspring per female, respectively, although cold storage significantly extended the shelf life. The survival rates of parasitoids that were placed in cold storage were 90.3% and 81.3% for females, and 3.2% and 0.9% for males of T. japonicus and T. cultratus, respectively. The number of hosts parasitized within 24h was not shown to be density dependent, but it was significantly lower after cold storage. Discussion: This information can be used to estimate the likely production for augmented rearing colonies for use in biological control programs.

Population growth of Prostephanus truncatus and Sitophilus zeamais and infestation patterns in three maize hybrids

Prostephanus truncatus (Horn) (Coleoptera: Bostrychidae) and Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae) cause significant damage to stored maize (Zea mays L.). In this study, we evaluated the progeny production and damage of these species in three maize hybrids (‘AGN 717’, ‘AGN 672’, and ‘AGN 794’) obtained from three locations in Northern Greece. The trials were conducted under laboratory conditions, and the progeny production, number of damaged kernels (NDK), weight of damaged kernels (WDK), and frass were evaluated after 65 days. The hybrids had a significant effect on the progeny production of both beetle species, with the highest number of progeny being produced in the hybrid ‘AGN 672’. The percentage of dead adults was affected by planting location of hybrids in both species, but no significant differences were found among the tested hybrids and species. The effect of location on frass production was only observed in S. zeamais, but hybrids did not affect the production of the frass in either species. NDK and WDK were found to be significantly different among the hybrids in S. zeamais, but only WDK was different in P. truncatus. These parameters did not differ among the locations for either species. The results showed that different hybrids and cropping locations had a significant effect on the progeny production and damage of S. zeamais and P. truncatus in maize. Therefore, planting locations and hybrids should be taken into account when growing maize or specified in maize susceptibility studies to P. truncatus and S. zeamais.

Quantitative Traits of Interest in Apple Breeding and Their Implications for Selection.

Apple breeding is a laborious and long-lasting process that requires qualified resources, land, time, and funds. In this study, more than 5000 F1 apple hybrids from direct and testcrosses were analyzed. The results revealed how the phenotypic expression of the main quantitative traits of interest assessed in five half-sib families was controlled by the additive genetic effects and by non-additive effects of dominance and epistasis. The statistical number of hybrids required to ensure efficient selection increased exponentially with the number of desirable traits. The minimum number of progenies required to obtain a hybrid with associated quantitative traits of agronomic interest was highly variable. For two independent traits essential in selection (fruit size and quality), but incorporated together in the same hybrid, the statistical number was between about 30 and 300. If three more cumulative traits were added (a large number of fruits per tree, resistance/tolerance to apple scab, and powdery mildew attack), the limits increased to between 1500 and 18,000. The study highlighted the need for new apple varieties due to the narrowing of the genetic diversity of the cultivated species and how the choice of parents used in hybridizations (as well as the objectives pursued in the selection) can increase the efficiency of apple breeding.

Benchmarking in a beef cattle breeding program: Lessons from the best breeders.

Beef cattle breeding programs offer genetic evaluations and consulting services on animal breeding practices to help breeders improve the genetic merit of their herds. Some breeders are more willing to apply best practices and technologies than others. Consequently, the average genetic merit and genetic trends differ across herds. We benchmarked some parameters of an average herd (AVE) and the corresponding parameters of herds with higher genetic merit (TOP), both participating in a commercial Nellore breeding program. Expected progeny differences (EPD) for growth, reproductive and carcass traits and a selection index (SI) of animals born from 2005 to 2019 on 128 farms located in Brazil, Bolivia and Paraguay were used to compute the AVE parameters. The 20 herds with higher mean SI of animals born in the last five birth seasons were classified as TOP herds. The mean SI and EPD of animals born in the last five seasons in the TOP herds were, respectively, 89% and 79% to 206% higher (p ≤ 0.001) than those of animals from the AVE herd. Genetic trends over the entire period were also higher (50% for SI and 31% to 88% separately for each trait, p ≤ 0.006) in the TOP herds compared to the AVE herd. Although the difference in the numbers of cows, bulls and calves between the TOP and AVE herds did not reach statistical significance (p=0.175, p=0.273 and p=0.061, respectively), the numbers of progeny per cow and per bull were 21% (p=0.012) and 26% (p=0.047) higher in the TOP herds, respectively. Multiple ovulation and embryo transfer and in vitro fertilization and embryo transfer (MOET/IVF) accounted for a higher percentage of births in the TOP herds compared to AVE (24.6% vs. 12.5%, p=0.002). The generation interval was 17% shorter (p < 0.001) in the TOP herds compared to AVE. The average inbreeding coefficient of animals from the TOP herds (1.08 ± 0.52%) did not differ (p=0.78) from that of AVE animals (1.26 ± 0.96%). In general, AVE herds are evolving in the desirable direction but differences in genetic merit between AVE and TOP herds are increasing over time. The more frequent use of MOET/IVF, a lower cow-to-bull ratio, and a larger family size (progeny per cow or per bull) can help achieve larger selection differentials and increase genetic trends and average genetic merits of TOP herds compared to AVE herds.

2,3-Diphosphoglycerate and the Protective Effect of Pyruvate Kinase Deficiency against Malaria Infection-Exploring the Role of the Red Blood Cell Membrane.

Malaria remains a major world public health problem, contributing to poverty and inequality. It is urgent to find new efficacious tools with few adverse effects. Malaria has selected red blood cell (RBC) alterations linked to resistance against infection, and understanding the protective mechanisms involved may be useful for developing host-directed tools to control Plasmodium infection. Pyruvate kinase deficiency has been associated with resistance to malaria. Pyruvate kinase-deficient RBCs display an increased concentration of 2,3-diphosphoglycerate (2,3-DPG). We recently showed that 2,3-DPG impacts in vitro intraerythrocytic parasite growth, induces a shift of the metabolic profile of infected cells (iRBCs), making it closer to that of noninfected ones (niRBCs), and decreases the number of parasite progenies that invade new RBCs. As an increase of 2,3-DPG content may also have an adverse effect on RBC membrane and, consequently, on the parasite invasion, in this study, we explored modifications of the RBC morphology, biomechanical properties, and RBC membrane on Plasmodium falciparum in vitro cultures treated with 2,3-DPG, using atomic force microscopy (AFM)-based force spectroscopy and other experimental approaches. The presence of infection by P. falciparum significantly increased the rigidity of parasitized cells and influenced the morphology of RBCs, as parasitized cells showed a decrease of the area-to-volume ratio. The extracellular addition of 2,3-DPG also slightly affected the stiffness of niRBCs, making it more similar to that of infected cells. It also changed the niRBC height, making the cells appear more elongated. Moreover, 2,3-DPG treatment influenced the cell surface charge, becoming more negative in treated RBCs than in untreated ones. The results indicate that treatment with 2,3-DPG has only a mild effect on RBCs in comparison with the effect of the presence of the parasite on the host cell. 2,3-DPG is an endogenous host metabolite, which may, in the future, originate a new antimalarial tool with few adverse effects on noninfected cells.

The combined effects of artificial light at night and anthropogenic noise on life history traits in ground crickets

AbstractUrbanization affects various biotic and abiotic conditions through the disturbance and modification of the environment by human activity. Anthropogenic noise and artificial light at night (ALAN) associated with urbanization have negative impacts on wildlife. However, few studies have focused on the combined effects of noise and ALAN, and the counter‐adaptation of urban individuals to environmental pollution. We examined the single and combined effects of ALAN and noise on life history traits, including developmental period, survival rate, egg diapause, the number of progeny, and body size, of the cricket Dianemobius nigrofasciatus. We examined whether urban individuals are adapted to these factors by a common garden experiment using the crickets of both urban and rural origin. Our findings revealed no combined effect of ALAN and noise on the life‐history traits of D. nigrofasciatus except on that of survival and progeny production. Both ALAN and noise alone delayed development and prevented egg diapause. Neither noise nor ALAN had a significant effect on body size. The survival rate of rural crickets was not affected by noise and ALAN, but there was a negative synergetic effect. However, there were no significant effects of ALAN, noise, or their combined effect on the survival rate of urban crickets. These results suggest that urban individuals exhibit adaptive evolution to these factors. The number of progeny was positively affected by noise and not affected by ALAN, while the combined effect negatively affected the progeny production. The results suggest that a combined effect of noise and ALAN on important factors for the cricket such as survival and reproduction.

Evaluation of In-Field Inoculation Methods for Characterization of Macadamia Germplasm to Husk Spot Incidence and Severity.

Husk spot, a fungal disease of macadamia pericarps (Pseudocercospora macadamiae), induces premature abscission in several major commercial cultivars. Breeding for resistance to husk spot is a priority of the Australian macadamia industry. Due to the large tree size of macadamia and high numbers of progeny in breeding populations, inoculating for resistance screening is laborious and time consuming. Previously utilized methods included direct applications of P. macadamiae suspensions and the hanging of bags of diseased husks above developing fruit in tree canopies. In this study, both methods were modified to allow for efficient application in large-scale breeding populations, and their efficacy was evaluated. Two quantities of diseased husk per bag, 'large' (75 g) and 'small' (30 g), and two concentrations of sprayed P. macadamiae suspensions, 'stock' (5 × 105 propagules/ml) and 'dilute' (2.5 × 105 propagules/ml), were tested across two fruiting seasons. Treatments were compared against a control (sterile water) in commercial cultivars A38 and A4. Husk spot incidence and severity produced by small bags were significantly affected by season. A significant season effect was less common for other treatments. All four treatments infected over 50% of target fruit in each season, but the highest husk spot incidence across both seasons (≥85%) was produced from large bags. Overall, the large bags were the most reliable method for infection of target fruit. Results also demonstrate the importance of considering the effect of season when selecting husk spot inoculation methods.

Generation of surrogate goldfish Carassius auratus progeny from common carp Cyprinus carpio parents.

Surrogate broodstock technology can increase the production efficiency of commercially important fishes that are difficult to breed in confinement and aid the propagation and recovery of endangered populations. In this study, we report the application of germ cell (GC) transplantation (GCT) for increasing the numbers of progeny produced by small-bodied ornamental fishes by using sexually mature adult fish as recipients. The GCs isolated from prepubertal male goldfish (Carassius auratus) donors (n = 5) were transplanted through the genital papilla into the gonads of adult common carp (Cyprinus carpio) recipients. The endogenous GCs of the recipient were depleted using busulfan (40mg/kg body weight [BW]; in five doses at 2-week intervals) and high-temperature (38°C) treatments. Within 4months after GCT, the donor GCs recolonised the recipients' gonads and resumed gametogenesis. The presence of donor-derived gametes was confirmed through polymerase chain reaction-restriction fragment length polymorphism analysis in all the surrogate common carp males and females. Artificial fertilisation and induced spawning between surrogate males and females yielded pure goldfish progeny; the fertilisation and hatching rates were similar to those of the controls. These results suggest that GCT could also be potentially applied in commercial aquaculture, mainly to increase the numbers of progeny obtained from small-bodied fishes those having low gamete counts.

Potential host range of Cotesia vanessae (Hymenoptera: Braconidae), a parasitoid new to North America and a possible biological control agent of noctuid pest species.

The likelihood of parasitoids establishing in new geographic regions depends upon the availability of suitable host species. Identifying these hosts and the degree of their suitability is particularly important when they include species that are economically important as pests. In laboratory studies, we examined the suitability of 47 species of Lepidoptera as potential hosts of a parthenogenetic strain of the gregarious parasitoid Cotesia vanessae (Hymenoptera: Braconidae). Previously known from Eurasia and northern Africa, the first known recovery of C. vanessae in North America was in 2009. C. vanessae completed development in 34 species, of which three were known hosts (Noctuidae) and 31 (30 Noctuidae, 1 Nymphalidae) were not. Many of these noctuid species are economic pests. Parasitoid fitness was generally highest on species of Plusiinae (Noctuidae), measured as either percentage of successful parasitism, developmental time, or number and mass of F1 progeny. Closely related species were generally similar in their suitability as hosts. In some cases, parasitoid eggs or larvae were killed by the immune system of the parasitized host, but the host eventually failed to excrete food waste, did not pupate, and ultimately died. Such cases reached up to 100% mortality depending upon the lepidopteran species. The suitability of many species of noctuid pests as hosts for C. vanessae suggests that this parasitoid will become established widely throughout North America and may help to suppress populations of some pest species.

Influence of Phaseolus vulgaris L. (Fabaceae: Fabales) varieties on oviposition behavior and susceptibility to infestation by Acanthoscelides obtectus Say (Coleoptera: Bruchidae)

Despite beans being a vital source of cheap protein, its yield is reduced mainly by diseases, field and storage pests. An effective and sustainable control option against storage insect pests could be improving the genetic resistance of the host plant in relation to the behaviour of the pest. A laboratory investigation was conducted to determine effects of bean varieties on oviposition behaviour and susceptibility to infestation by Acanthoscelides obtectus. The experiments evaluated oviposition site preference, number of eggs laid, and number of progeny and emergence holes of A. obtectus per bean variety. The number of progeny and duration in days taken by 50 % of progeny to emerge was determined and used to calculate susceptibility index. Seed harness index, thickness of testae and surface area of bean varieties were determined and related with susceptibility indices. Results indicated that the number of eggs laid, progeny, and emergence holes, duration taken by progeny to emerge, susceptibility indices, seed surface area and hardness were statistically different. Mwezi moja variety was the most preferred host for oviposition whereas Mwitemania was the least preferred. Beetles laid the highest (84.5) number of eggs in Mwezi moja and the least (41.9) in Mwitemania. Number of progeny of A. obtectus emerging were the highest in Mwezi moja (73.7) and the least (36) in Mwitemania. Beetles took the shortest (36.75 days) period to emerge from Mwezi moja and the longest (38.63days) period from Mwitemania. Mwezi moja was the most susceptible variety to attack by A. obtectus with a susceptibility index of 7.43 and Mwitemania was the least susceptible with an index of 6.51. Nyayo had the highest (0.019) seed hardness index and Mwezi moja and Canadian wonder had the least (0.012) hardness index. Mwezi moja had the largest (278mm) surface area whereas Mwitemania had the lowest (171mm) surface area.

Regularities of reproduction for fall Chum salmon Oncorhynchys keta from the Аmur river

The dependence of the number of progeny of the Amur fall chum salmon Oncorhynchys keta on the number of parents was analyzed. It is shown that the deviations of the actual number of offspring from the theoretical ones, calculated by the Ricker equation, depend on the belonging of the fish to a particular generation. An equation is proposed that describes the dependence of the number of progeny of the autumn chum salmon on the number of parents and reproduction conditions. The problem of the variability of the optimal number of parents due to the change in reproduction levels is discussed.

Predation risk regulates prey assortative mating by reducing the expected reproductive value of mates.

Many animals exhibit size assortative mating (SAM), but how predation affects it remains largely unknown. We hypothesized that predation risk may turn prey less choosy, disrupting SAM, or reduce the expected reproductive value of mates, maintaining SAM but with different size ratio between mates. Using a manipulative field experiment, we found that desert isopods under risk of scorpion predation maintained SAM, but that males that choose and fight over females were on average smaller for a given female size. Less pairs were formed in risky sites, but there were no differences in female sizes and progeny number, size and age near and away from scorpion burrows. Our complementary behavioral experiments revealed that bigger males stayed longer near safe burrows, and won more male-male contests than smaller conspecifics. Our findings highlight that prey can anticipate future costs of predation and use this information to assess the expected reproductive value of mates.

Yinjia pill inhibits persistent Chlamydia trachomatis infection.

Yinjia pill inhibits persistent Chlamydia trachomatis infection.

Stored rice varietal resistance towards Sitophilus oryzae

Previous research has demonstrated that varieties of rice are differentially susceptible to stored rice pests, but modern varieties are lacking evaluation. Thirteen varieties of rice, Oryzae sativa (L.), were tested for their susceptibility to the rice weevil, Sitophilus oryzae (L.). Sitophilus oryzae adults were placed into vials containing one of 13 USA commercial rice varieties. Adult damage, larval damage, days to eclosion, total progeny, and progeny mass were recorded over a period of six weeks. Subsequently, varietal mixes of the resistant and susceptible varieties were evaluated for associational resistance or susceptibility using the same methodology. Rice variety impacted adult damage, larval damage, progeny counts, progeny mass, and development time. The rice variety most susceptible to adult damage had 11-fold greater damage than the rice variety most resistant to adults. Similarly, the rice variety most susceptible to larval damage received 10-fold more damage than the most resistant. Progeny had the shortest development time and greatest adult mass feeding on high protein, low-glycemic rice variety, Frontière. Varietal mixes often resulted in associational susceptibility, where mixes of two rice varieties resulted in damage equal to or greater than that of the most susceptible variety in the mix. Blends created similar changes in the numbers of progeny, progeny mass, and development time. These results demonstrate the importance of stored rice varietal susceptibility, blend susceptibility, and their impact on stored rice pest management.

Estimation of Genetic Parameters and Optimum Breeding Programme Design in Korean Flatfish Breeding Population

Olive flounder (Paralichthys olivaceus) is a vital aquaculture species in East Asia. However, few studies that estimate the genetic parameters of this species have been conducted. We estimated the genetic parameters of growth traits and designed an optimum breeding programme for this species. Heritability, genetic and phenotypic correlations, and breeding values were estimated for growth traits: body weight (BW), total length (TL), and condition factor (CF). A linear mixed animal model using the restricted maximum likelihood (REML) algorithm was applied to the statistical analysis of 9 traits (BW, TL, and CF at 11, 18, and 22 months of age) for a total of 54,159 animals from 7 generations. Increases of 13%, 8%, and 6.5% in BW, TL, and CF at the harvest stage were observed, respectively, after 7 generations of selection. The heritabilities of all growth traits were moderate, ranging from 0.35 to 0.46. The phenotypic and genetic correlations between BW and TL were high and positive in all three stages (0.91 and 0.92, 0.91 and 0.93, and 0.88 and 0.91). The estimated breeding values of BW and TL increased over the generations; however, the estimated breeding value of CF fluctuated. The optimum progeny number within full-sib families for an accuracy of 0.632 is suggested to be between 10 and 25. Findings indicated that a considerable response to selection and single-trait selection based on BW would be effective in olive flounder.

Improved productivity of naturalized spring Chinook salmon following reintroduction from a hatchery stock in Lookingglass Creek, Oregon

Supplementation of depressed salmonid populations with hatchery production has been questioned due to domestication effects, which may reduce reproductive fitness. However, for extirpated populations, reintroduction typically requires use of hatchery stocks. We evaluated this strategy by monitoring the naturalization of spring Chinook salmon reintroduced to Lookingglass Creek, OR (Grande Ronde Basin), from a captive brood, hatchery stock. We compared the reproductive success (RS) of naturally spawning natural-origin relative (NOR) to hatchery-origin (HOR) adults across 9 brood years. Individual RS (the number of progeny produced) was estimated by pedigree reconstruction analyses, and then analyzed by generalized linear models to estimate the effect of parental origin, while controlling for potentially confounding covariates. When evaluating RS by juvenile progeny, NOR spawners were more likely to be reproductively successful, and when successful, produced more progeny on average than successful HOR counterparts. We found a similar advantage when evaluating RS by adult progeny, although the origin effect was not as important among successful spawners. Results suggest fish reintroduced from a hatchery stock possess the adaptive capacity to positively contribute to natural productivity and recovery goals.