The Experts below are selected from a list of 49047 Experts worldwide ranked by ideXlab platform
William E Feeney - One of the best experts on this subject based on the ideXlab platform.
-
insights into the successful Breeding of hawksbill sea turtles eretmochelys imbricata from a long term captive Breeding Program
Global Ecology and Conservation, 2020Co-Authors: Ruth Maggeni, William E FeeneyAbstract:Abstract Sea turtle populations are declining and evidence-based methods for supporting their populations are required. Captive Breeding and release Programs can be effective, offering the opportunity to supplement nature populations; however, sea turtles require specific conditions to successfully breed. Here, we present insights gained from a 12 year Hawksbill sea turtle (Eretmochelys imbricata) captive Breeding Program that was conducted at the Underwater Observatory Marine Park, Eilat, Israel, between 1982 and 1997. As the first Program of its kind for the Hawksbill sea turtle, insights were gained largely through trial-and-error and advice from experienced individuals. The key insight gained during this Program was the critical importance of pre-Breeding separation of the sexes; turtles did not breed prior to pre-Breeding separation being implemented, but it became predictably regular once it was. Over the course of the Program, 161 two-three year old hatchlings were introduced to the Red Sea, which was enabled largely as a result of pre-Breeding separation being implemented.
-
insights into the successful Breeding of hawksbill sea turtles eretmochelys imbricata from a long term captive Breeding Program
bioRxiv, 2020Co-Authors: Ruth Maggeni, William E FeeneyAbstract:Abstract Sea turtle populations are declining and evidence-based methods for supporting their populations are required. Captive Breeding and release Programs can be effective, offering the opportunity to supplement nature populations; however, sea turtles require specific conditions to successfully breed. Here, we present insights gained from a 16 year Hawksbill sea turtle (Eretmochelys imbricata) captive Breeding Program that was conducted at the Underwater Observatory Marine Park, Eilat, Israel, between 1982-1997. As the first Program of its kind for the Hawksbill sea turtle, insights were gained largely through trial-and-error and word of mouth advice. The key insight gained during this Program was the critical importance of pre-Breeding separation of the sexes; turtles did not breed prior to pre-Breeding separation being implemented, but it became predictably regular once it was. Over the course of the Program, 161 two-three years old hatchlings were introduced to the Red Sea, which was enabled largely as a result of pre-Breeding separation being implemented.
Ruth Maggeni - One of the best experts on this subject based on the ideXlab platform.
-
insights into the successful Breeding of hawksbill sea turtles eretmochelys imbricata from a long term captive Breeding Program
Global Ecology and Conservation, 2020Co-Authors: Ruth Maggeni, William E FeeneyAbstract:Abstract Sea turtle populations are declining and evidence-based methods for supporting their populations are required. Captive Breeding and release Programs can be effective, offering the opportunity to supplement nature populations; however, sea turtles require specific conditions to successfully breed. Here, we present insights gained from a 12 year Hawksbill sea turtle (Eretmochelys imbricata) captive Breeding Program that was conducted at the Underwater Observatory Marine Park, Eilat, Israel, between 1982 and 1997. As the first Program of its kind for the Hawksbill sea turtle, insights were gained largely through trial-and-error and advice from experienced individuals. The key insight gained during this Program was the critical importance of pre-Breeding separation of the sexes; turtles did not breed prior to pre-Breeding separation being implemented, but it became predictably regular once it was. Over the course of the Program, 161 two-three year old hatchlings were introduced to the Red Sea, which was enabled largely as a result of pre-Breeding separation being implemented.
-
insights into the successful Breeding of hawksbill sea turtles eretmochelys imbricata from a long term captive Breeding Program
bioRxiv, 2020Co-Authors: Ruth Maggeni, William E FeeneyAbstract:Abstract Sea turtle populations are declining and evidence-based methods for supporting their populations are required. Captive Breeding and release Programs can be effective, offering the opportunity to supplement nature populations; however, sea turtles require specific conditions to successfully breed. Here, we present insights gained from a 16 year Hawksbill sea turtle (Eretmochelys imbricata) captive Breeding Program that was conducted at the Underwater Observatory Marine Park, Eilat, Israel, between 1982-1997. As the first Program of its kind for the Hawksbill sea turtle, insights were gained largely through trial-and-error and word of mouth advice. The key insight gained during this Program was the critical importance of pre-Breeding separation of the sexes; turtles did not breed prior to pre-Breeding separation being implemented, but it became predictably regular once it was. Over the course of the Program, 161 two-three years old hatchlings were introduced to the Red Sea, which was enabled largely as a result of pre-Breeding separation being implemented.
Jeffrey A. Hutchings - One of the best experts on this subject based on the ideXlab platform.
-
risk assessment of inBreeding and outBreeding depression in a captive Breeding Program
Conservation Biology, 2014Co-Authors: Njal Rollinson, Aimee Lee S Houde, Dave M Keith, Meghan C Mcbride, P V Debes, Jeffrey A. HutchingsAbstract:Captive-Breeding Programs can be implemented to preserve the genetic diversity of endangered populations such that the controlled release of captive-bred individuals into the wild may promote recovery. A common difficulty, however, is that Programs are founded with limited wild broodstock, and inBreeding can become increasingly difficult to avoid with successive generations in captivity. Program managers must choose between maintaining the genetic purity of populations, at the risk of inBreeding depression, or interBreeding populations, at the risk of outBreeding depression. We evaluate these relative risks in a captive-Breeding Program for 3 endangered populations of Atlantic salmon (Salmo salar). In each of 2 years, we released juvenile F1 and F2 interpopulation hybrids, backcrosses, as well as inbred and noninbred within-population crosstypes into 9 wild streams. Juvenile size and survival was quantified in each year. Few crosstype effects were observed, but interestingly, the relative fitness consequences of inBreeding and outBreeding varied from year to year. Temporal variation in environmental quality might have driven some of these annual differences, by exacerbating the importance of maternal effects on juvenile fitness in a year of low environmental quality and by affecting the severity of inBreeding depression differently in different years. Nonetheless, inBreeding was more consistently associated with a negative effect on fitness, whereas the consequences of outBreeding were less predictable. Considering the challenges associated with a sound risk assessment in the wild and given that the effect of inBreeding on fitness is relatively predictable, we suggest that risk can be weighted more strongly in terms of the probable outcome of outBreeding. Factors such as genetic similarities between populations and the number of generations in isolation can sometimes be used to assess outBreeding risk, in lieu of experimentation. Evaluacion del Riesgo de Depresion por Endogamia y Exogamia en un Programa de Reproduccion en Cautiverio Resumen Los Programas de reproduccion en cautiverio pueden ser implementados para preservar la diversidad genetica de las poblaciones en peligro, de tal forma que la liberacion controlada de los individuos criados en cautiverio a la vida libre puede promover la recuperacion. Sin embargo, una dificultad comun es que los Programas se encuentran dentro del limitado capital de reproduccion silvestre, y la endogamia puede volverse cada vez mas dificil de evitar con generaciones sucesivas en cautiverio. Los directores del Programa deben elegir entre mantener la pureza genetica de las poblaciones, con el riesgo de una depresion endogamica, o reproducir entre poblaciones, con el riesgo de una depresion exogamica. Evaluamos estos riesgos relativos en un Programa de reproduccion en cautiverio para tres poblaciones en peligro de salmon del Atlantico (Salmo salar). Cada 2 anos, liberamos juveniles hibridos inter-poblacionales F1 y F2, retrocruzamientos, asi como cruzas endogamicas y no endogamicas entre poblaciones en nueve arroyos silvestres. El tamano juvenil y la supervivencia se cuantificaron cada ano. Se observaron pocos efectos de cruza, pero interesantemente, las consecuencias de la adaptabilidad relativa de la endogamia y exogamia variaron ano con ano. La variacion temporal en la calidad ambiental pudo ser conductora en alguna de estas diferencias anuales, al exacerbar la importancia de los efectos maternales sobre la aptitud juvenil en un ano de baja calidad ambiental y al afectar diferentemente la severidad de la depresion endogamica en anos diferentes. Sin embargo, la endogamia fue asociada constantemente con un efecto negativo sobre la adaptabilidad, mientras que las consecuencias de la exogamia fueron menos predecibles. Considerando los obstaculos asociados con un estudio concreto de riesgo en vida silvestre y dado que el efecto de la endogamia sobre la aptitud es relativamente predecible, sugerimos que el riesgo puede considerarse mas fuerte en terminos de un resultado probable de la exogamia. Factores como las similitudes geneticas entre poblaciones y el numero de generaciones en aislamiento puede usarse algunas veces para estudiar el riesgo de la exogamia, en lugar de la experimentacion.
-
risk assessment of inBreeding and outBreeding depression in a captive Breeding Program
Conservation Biology, 2014Co-Authors: Njal Rollinson, Aimee Lee S Houde, Dave M Keith, Meghan C Mcbride, P V Debes, Jeffrey A. HutchingsAbstract:Captive-Breeding Programs can be implemented to preserve the genetic diversity of endangered populations such that the controlled release of captive-bred individuals into the wild may promote recovery. A common difficulty, however, is that Programs are founded with limited wild broodstock, and inBreeding can become increasingly difficult to avoid with successive generations in captivity. Program managers must choose between maintaining the genetic purity of populations, at the risk of inBreeding depression, or interBreeding populations, at the risk of outBreeding depression. We evaluate these relative risks in a captive-Breeding Program for 3 endangered populations of Atlantic salmon (Salmo salar). In each of 2 years, we released juvenile F(1) and F(2) interpopulation hybrids, backcrosses, as well as inbred and noninbred within-population crosstypes into 9 wild streams. Juvenile size and survival was quantified in each year. Few crosstype effects were observed, but interestingly, the relative fitness consequences of inBreeding and outBreeding varied from year to year. Temporal variation in environmental quality might have driven some of these annual differences, by exacerbating the importance of maternal effects on juvenile fitness in a year of low environmental quality and by affecting the severity of inBreeding depression differently in different years. Nonetheless, inBreeding was more consistently associated with a negative effect on fitness, whereas the consequences of outBreeding were less predictable. Considering the challenges associated with a sound risk assessment in the wild and given that the effect of inBreeding on fitness is relatively predictable, we suggest that risk can be weighted more strongly in terms of the probable outcome of outBreeding. Factors such as genetic similarities between populations and the number of generations in isolation can sometimes be used to assess outBreeding risk, in lieu of experimentation.
Michel C. Milinkovitch - One of the best experts on this subject based on the ideXlab platform.
-
Molecular genetic analysis of a captive-Breeding Program: the vulnerable endemic Jamaican yellow boa
Conservation Genetics, 2009Co-Authors: Athanasia C. Tzika, Christophe Remy, Richard Gibson, Michel C. MilinkovitchAbstract:The endemic Jamaican boa (or “yellow boa”, Epicrates subflavus ) is a vulnerable species of the Caribbean biodiversity hotspot whose natural populations greatly declined mainly due to predation by introduced species, human persecution, and habitat destruction. A captive Breeding Program was initiated in 1976 and rationalized in 2002 by the establishment of a European Endangered Species Program . During the last 30 years, more than 600 offspring, of which 80 are still alive today, have been produced and distributed among European host institutions and privates. Here, using nine nuclear microsatellite loci and a fragment of the mitochondrial cytochrome b gene, we (i) determine the natural population from which the founders originate, (ii) identify parental allocation errors and ambiguities in the studbook, and (iii) assess the genetic diversity and estimate levels of inBreeding of the current captive population based on loss of alleles, variance in reproductive success, and relatedness among individuals. Combining measures of relatedness derived from multilocus genotypes with practical parameters such as age of animals and localization of host institutions, we propose mating groups that would maximize genetic diversity in the captive population of the Jamaican boa. Our analyses provide guidance for a more efficient Breeding Program that, in turn, could be used as the starting point of a repatriation Program to increase the probability of the species long-term survival.
Arron H Carter - One of the best experts on this subject based on the ideXlab platform.
-
gains through selection for grain yield in a winter wheat Breeding Program
PLOS ONE, 2020Co-Authors: Dennis N Lozada, Brian P Ward, Arron H CarterAbstract:Increased genetic gain for complex traits in plant Breeding Programs can be achieved through different selection strategies. The objective of this study was to compare potential gains for grain yield in a winter wheat Breeding Program through estimating response to selection R values across several selection approaches including phenotypic (PS), marker-based (MS), genomic (GS), and a combination of PS and GS (PS+GS). Ten populations of Washington State University (WSU) winter wheat Breeding lines including a diversity panel and F5 and double haploid lines evaluated from 2015 to 2019 growing seasons for grain yield in Lind and Pullman, WA, USA were used in the study. Selection was conducted by selecting the top 20% of lines based on observed yield (PS strategy), genomic estimated Breeding values (GS), presence of yield "enhancing" alleles of the most significant single nucleotide polymorphism (SNP) markers identified from genome-wide association mapping (MS), and high observed yield and estimated Breeding values (PS+GS). Overall, PS compared to other individual selection strategies (MS and GS) showed the highest mean response (R = 0.61) within the same environment. When combined with GS, a 23% improvement in R for yield was observed, indicating that gains could be improved by complementing traditional PS with GS within the same environment. Validating selection strategies in different environments resulted in low to negative R values indicating the effects of genotype-by-environment interactions for grain yield. MS was not successful in terms of R relative to the other selection approaches; using this strategy resulted in a significant (P < 0.05) decrease in response to selection compared with the other approaches. An integrated PS+GS approach could result in optimal genetic gain within the same environment, whereas a PS strategy might be a viable option for grain yield validated in different environments. Altogether, we demonstrated that gains through increased response to selection for yield could be achieved in the WSU winter wheat Breeding Program by implementing different selection strategies either exclusively or in combination.
-
gains through selection for grain yield in a winter wheat Breeding Program
bioRxiv, 2019Co-Authors: Dennis N Lozada, Arron H CarterAbstract:Abstract Increased genetic gains for complex traits in plant Breeding Programs can be achieved through different selection strategies. The objective of this study was to compare potential gains for grain yield in a winter wheat Breeding Program through estimating response to selection R values across several selection approaches including phenotypic (PS), marker-based (MS), genomic (GS), and a combination of PS and GS. Five populations of Washington State University (WSU) winter wheat Breeding lines evaluated from 2015 to 2018 in Lind and Pullman, WA, USA were used in the study. Selection was conducted by selecting the top 20% of lines based on observed yield (PS strategy), genomic estimated Breeding values (GS), presence of yield “enhancing” alleles of the most significant single nucleotide polymorphism (SNP) markers identified from genome-wide association mapping (MS), and high observed yield and estimated Breeding values (PS+GS). Overall, PS compared to other individual strategies showed the highest response. However, when combined with GS, a 23% improvement in R for yield was observed, indicating that gains could be improved by complementing traditional PS with GS. Using GS alone as a selection strategy for grain yield should be taken with caution. MS was not that successful in terms of R relative to the other selection approaches. Altogether, we demonstrated that gains through increased response to selection for yield could be achieved in the WSU winter wheat Breeding Program by implementing different selection strategies either exclusively or in combination.