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Tollervey MJ, Bekaert M, González AB, Agha S, Houston RD, Doeschl‐Wilson A, Norris A, Migaud H, Gutierrez AP. Assessing genotype-environment interactions in Atlantic salmon reared in freshwater loch and recirculating systems. Evol Appl 2024; 17:e13751. [PMID: 39131541 PMCID: PMC11310769 DOI: 10.1111/eva.13751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Revised: 03/18/2024] [Accepted: 06/19/2024] [Indexed: 08/13/2024] Open
Abstract
The interest in recirculating aquaculture systems (RAS) is growing due to their benefits such as increased productivity, better control over animal care, reduced environmental effects, and less water consumption. However, in some regions of the world, traditional aquaculture methods remain prevalent, and selective breeding has often been designed for performance within these systems. Therefore, it is important to evaluate how current fish populations fare in RAS to guide future breeding choices. In a commercial setting, we explore the genetic structure of growth characteristics, measure genotype-environment interactions (GxE) in salmon smolts, and examine genetic markers related to growth in freshwater lochs and RAS. Young salmon were raised together until they reached the parr stage, after which they were divided equally between freshwater net-pens and RAS. After an 8-week period, we sampled fish from each environment and genotyped them. Our findings revealed that fish reared in RAS were generally smaller in weight and length but exhibited a higher condition factor and uniformity. We found a notably smaller component of unexplained variance in the RAS, leading to higher heritability estimates. We observed a low GxE effect for length and condition factor, but significant re-ranking for whole-body weight, as well as noticeable differences in trait associations across environments. Specifically, a segment of chromosome 22 was found to be linked with the condition factor in the RAS population only. Results suggests that if the use of RAS continues to expand, the efficiency of existing commercial populations may not reach its full potential unless breeding programs specific to RAS are implemented.
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Affiliation(s)
| | - Michaël Bekaert
- Institute of AquacultureUniversity of StirlingStirlingUK
- Cooke Aquaculture Scotland, Avondale House, Strathclyde Business ParkBellshillUK
| | | | - Saif Agha
- Roslin InstituteThe University of EdinburghEdinburghUK
- Animal Production Department, Faculty of AgricultureAin Shams UniversityShubra Alkhaima, CairoEgypt
| | | | | | | | - Herve Migaud
- Institute of AquacultureUniversity of StirlingStirlingUK
- Mowi Scotland, Glen Nevis Business ParkFort WilliamUK
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Raffo MA, Cuyabano BCD, Rincent R, Sarup P, Moreau L, Mary-Huard T, Jensen J. Genomic prediction for grain yield and micro-environmental sensitivity in winter wheat. FRONTIERS IN PLANT SCIENCE 2023; 13:1075077. [PMID: 36816478 PMCID: PMC9929036 DOI: 10.3389/fpls.2022.1075077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 12/23/2022] [Indexed: 06/18/2023]
Abstract
Individuals within a common environment experience variations due to unique and non-identifiable micro-environmental factors. Genetic sensitivity to micro-environmental variation (i.e. micro-environmental sensitivity) can be identified in residuals, and genotypes with lower micro-environmental sensitivity can show greater resilience towards environmental perturbations. Micro-environmental sensitivity has been studied in animals; however, research on this topic is limited in plants and lacking in wheat. In this article, we aimed to (i) quantify the influence of genetic variation on residual dispersion and the genetic correlation between genetic effects on (expressed) phenotypes and residual dispersion for wheat grain yield using a double hierarchical generalized linear model (DHGLM); and (ii) evaluate the predictive performance of the proposed DHGLM for prediction of additive genetic effects on (expressed) phenotypes and its residual dispersion. Analyses were based on 2,456 advanced breeding lines tested in replicated trials within and across different environments in Denmark and genotyped with a 15K SNP-Illumina-BeadChip. We found that micro-environmental sensitivity for grain yield is heritable, and there is potential for its reduction. The genetic correlation between additive effects on (expressed) phenotypes and dispersion was investigated, and we observed an intermediate correlation. From these results, we concluded that breeding for reduced micro-environmental sensitivity is possible and can be included within breeding objectives without compromising selection for increased yield. The predictive ability and variance inflation for predictions of the DHGLM and a linear mixed model allowing heteroscedasticity of residual variance in different environments (LMM-HET) were evaluated using leave-one-line-out cross-validation. The LMM-HET and DHGLM showed good and similar performance for predicting additive effects on (expressed) phenotypes. In addition, the accuracy of predicting genetic effects on residual dispersion was sufficient to allow genetic selection for resilience. Such findings suggests that DHGLM may be a good choice to increase grain yield and reduce its micro-environmental sensitivity.
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Affiliation(s)
- Miguel A. Raffo
- Center for Quantitative Genetics and Genomics, Aarhus University, Aarhus, Denmark
| | - Beatriz C. D. Cuyabano
- Université Paris Saclay, INRAE, AgroParisTech, GABI, Domaine de Vilvert, Jouy-en-Josas, France
| | - Renaud Rincent
- Génétique Quantitative et Evolution − Le Moulon, INRAE, CNRS, AgroParisTech, Université Paris-Saclay, Gif−sur−Yvette, France
| | | | - Laurence Moreau
- Génétique Quantitative et Evolution − Le Moulon, INRAE, CNRS, AgroParisTech, Université Paris-Saclay, Gif−sur−Yvette, France
| | - Tristan Mary-Huard
- Génétique Quantitative et Evolution − Le Moulon, INRAE, CNRS, AgroParisTech, Université Paris-Saclay, Gif−sur−Yvette, France
- Université Paris-Saclay, AgroParisTech, INRAE, UMR MIA-Paris Saclay, Palaiseau, France
| | - Just Jensen
- Center for Quantitative Genetics and Genomics, Aarhus University, Aarhus, Denmark
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Bedere N, Berghof TVL, Peeters K, Pinard-van der Laan MH, Visscher J, David I, Mulder HA. Using egg production longitudinal recording to study the genetic background of resilience in purebred and crossbred laying hens. Genet Sel Evol 2022; 54:26. [PMID: 35439920 PMCID: PMC9020098 DOI: 10.1186/s12711-022-00716-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 03/28/2022] [Indexed: 12/02/2022] Open
Abstract
Background There is growing interest in using genetic selection to obtain more resilient farm animals (i.e. that are minimally affected by disturbances or rapidly recover from them). The aims of this study were to: (i) estimate the genetic parameters of resilience indicator traits based on egg production data, (ii) assess whether these traits are genetically correlated in purebreds and crossbreds, and (iii) assess the genetic correlations of these traits with egg production (EP) as total number of eggs between 25 and 83 weeks. Purebred hens (33,825 from a White Leghorn (WA) line and 34,397 from a Rhode Island (BD) line were housed in individual cages, while crossbred hens were housed in collective cages of 6 to 8 paternal half-sibs (12,852 WA and 3898 BD crossbred groups, where the name of the group refers to the line used as the sire). Deviations of a hen’s weekly egg production from the average of the corresponding batch were calculated. Resilience indicator traits investigated were the natural logarithm of the variance (LNVAR), the skewness (SKEW), and the lag-one autocorrelation (AUTO-R) of these deviations. Results In both purebred lines, EP was estimated to be lowly heritable (WA: 0.11 and BD: 0.12). Resilience indicators were also estimated to be lowly heritable in both lines (LNVAR: 0.10 and 0.12, SKEW: 0.04 and 0.02, AUTO-R: 0.06 and 0.08 in WA and BD, respectively). In both crossbred groups, EP, AUTO-R, and SKEW were estimated to be less heritable than in purebreds (EP: \documentclass[12pt]{minimal}
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\begin{document}$$h^{2}$$\end{document}h2 ≤ 0.07; and resilience indicator traits: \documentclass[12pt]{minimal}
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\begin{document}$$h^{2}$$\end{document}h2 ≤ 0.03), while LNVAR had an \documentclass[12pt]{minimal}
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\begin{document}$$h^{2}$$\end{document}h2 estimate that was similar to or higher in crossbreds (\documentclass[12pt]{minimal}
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\begin{document}$$h^{2}$$\end{document}h2 ranged from 0.13 to 0.21) than in purebreds. In both purebreds and crossbreds, resilience indicator traits were estimated to have favorable genetic correlations with EP and between each other. For all traits and in both lines, estimates of genetic correlations between purebreds and crossbreds (\documentclass[12pt]{minimal}
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\begin{document}$$r_{pc}$$\end{document}rpc) differed from 1 and ranged from 0.16 to 0.63. Conclusions These results show that selection for resilience based on EP data can be considered in breeding programs for layers. Genetic improvement of resilience in crossbreds can be achieved by using information on purebreds, but would be greatly enhanced by the integration of information on crossbreds in breeding programs. Supplementary Information The online version contains supplementary material available at 10.1186/s12711-022-00716-8.
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Affiliation(s)
- Nicolas Bedere
- PEGASE, INRAE, Institut Agro, 35590, Saint Gilles, France.
| | - Tom V L Berghof
- Wageningen University & Research Animal Breeding & Genomics, P.O. Box 338, 6700 AH, Wageningen, The Netherlands.,Reproductive Biotechnology, TUM School of Life Sciences, Technical University of Munich, Liesel‑Beckmann‑Strasse 1, 85354, Freising, Germany
| | - Katrijn Peeters
- Hendrix Genetics B.V., P.O. Box 114, 5830 AC, Boxmeer, The Netherlands
| | | | - Jeroen Visscher
- Hendrix Genetics B.V., P.O. Box 114, 5830 AC, Boxmeer, The Netherlands
| | - Ingrid David
- GenPhySE, Université de Toulouse, INRAE, ENVT, 31320, Castanet Tolosan, France
| | - Han A Mulder
- Wageningen University & Research Animal Breeding & Genomics, P.O. Box 338, 6700 AH, Wageningen, The Netherlands
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Marjanovic J, Mulder HA, Rönnegård L, de Koning D, Bijma P. Capturing indirect genetic effects on phenotypic variability: Competition meets canalization. Evol Appl 2022; 15:694-705. [PMID: 35505880 PMCID: PMC9046766 DOI: 10.1111/eva.13353] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 01/31/2022] [Indexed: 11/30/2022] Open
Abstract
Phenotypic variability of a genotype is relevant both in natural and domestic populations. In the past two decades, variability has been studied as a heritable quantitative genetic trait in its own right, often referred to as inherited variability or environmental canalization. So far, studies on inherited variability have only considered genetic effects of the focal individual, that is, direct genetic effects on inherited variability. Observations from aquaculture populations and some plants, however, suggest that an additional source of genetic variation in inherited variability may be generated through competition. Social interactions, such as competition, are often a source of Indirect Genetic Effects (IGE). An IGE is a heritable effect of an individual on the trait value of another individual. IGEs may substantially affect heritable variation underlying the trait, and the direction and magnitude of response to selection. To understand the contribution of IGEs to evolution of environmental canalization in natural populations, and to exploit such inherited variability in animal and plant breeding, we need statistical models to capture this effect. To our knowledge, it is unknown to what extent the current statistical models commonly used for IGE and inherited variability capture the effect of competition on inherited variability. Here, we investigate the potential of current statistical models for inherited variability and trait values, to capture the direct and indirect genetic effects of competition on variability. Our results show that a direct model of inherited variability almost entirely captures the genetic sensitivity of individuals to competition, whereas an indirect model of inherited variability captures the cooperative genetic effects of individuals on their partners. Models for trait levels, however, capture only a small part of the genetic effects of competition. The estimation of direct and indirect genetic effects of competition, therefore, is possible with models for inherited variability but may require a two-step analysis.
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Affiliation(s)
- Jovana Marjanovic
- Animal Breeding and GenomicsWageningen University and ResearchWageningenThe Netherlands
- Department of Animal Breeding and GeneticsSwedish University of Agricultural SciencesUppsalaSweden
| | - Han A. Mulder
- Animal Breeding and GenomicsWageningen University and ResearchWageningenThe Netherlands
| | - Lars Rönnegård
- Department of Animal Breeding and GeneticsSwedish University of Agricultural SciencesUppsalaSweden
- Department of Information TechnologyDalarna UniversityFalunSweden
| | - Dirk‐Jan de Koning
- Department of Animal Breeding and GeneticsSwedish University of Agricultural SciencesUppsalaSweden
| | - Piter Bijma
- Animal Breeding and GenomicsWageningen University and ResearchWageningenThe Netherlands
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O'Dea RE, Noble DWA, Nakagawa S. Unifying individual differences in personality, predictability and plasticity: A practical guide. Methods Ecol Evol 2021. [DOI: 10.1111/2041-210x.13755] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Rose E. O'Dea
- Evolution & Ecology Research Centre School of Biological and Environmental Sciences University of New South Wales Sydney NSW Australia
- Diabetes and Metabolism Division Garvan Institute of Medical Research Sydney NSW Australia
| | - Daniel W. A. Noble
- Division of Ecology and Evolution Research School of Biology The Australian National University Canberra ACT Australia
| | - Shinichi Nakagawa
- Evolution & Ecology Research Centre School of Biological and Environmental Sciences University of New South Wales Sydney NSW Australia
- Diabetes and Metabolism Division Garvan Institute of Medical Research Sydney NSW Australia
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García-Ballesteros S, Villanueva B, Fernández J, Gutiérrez JP, Cervantes I. Genetic parameters for uniformity of harvest weight in Pacific white shrimp (Litopenaeus vannamei). Genet Sel Evol 2021; 53:26. [PMID: 33711925 PMCID: PMC7953633 DOI: 10.1186/s12711-021-00621-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 03/01/2021] [Indexed: 11/10/2022] Open
Abstract
Background Uniformity of body weight is a trait of great economic importance in the production of white shrimp (Litopenaeus vannamei). A necessary condition to improve this trait through selective breeding is the existence of genetic variability for the environmental variance of body weight. Although several studies have reported such variability in other aquaculture species, to our knowledge, no estimates are available for shrimp. Our aim in this study was to estimate the genetic variance for weight uniformity in a farmed population of shrimp to determine the potential of including this trait in the selection program. We also estimated the genetic correlation of weight uniformity between two environments (selection nucleus and commercial population). Methods The database contained phenotypic records for body weight on 51,346 individuals from the selection nucleus and 38,297 individuals from the commercial population. A double hierarchical generalized linear model was used to analyse weight uniformity in the two environments. Fixed effects included sex and year for the nucleus data and sex and year-pond combination for the commercial data. Environmental and additive genetic effects were included as random effects. Results The estimated genetic variance for weight uniformity was greater than 0 (0.06 ± 0.01) in both the nucleus and commercial populations and the genetic coefficient of variation for the residual variance was 0.25 ± 0.01. The genetic correlation between weight and weight uniformity was close to zero in both environments. The estimate of the genetic correlation of weight uniformity between the two environments (selection nucleus and commercial population) was 0.64 ± 0.06. Conclusions The existence of genetic variance for weight uniformity suggests that genetic improvement of this trait is possible. Selection for weight uniformity should not decrease weight, given the near zero genetic correlation between these two traits. The strong genetic correlation of weight uniformity between the two environments indicates that response to selection for uniformity in the nucleus will be at least partially transmitted to the commercial population if this trait is included in the breeding goal.
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Affiliation(s)
| | | | - Jesús Fernández
- Departamento de Mejora Genética Animal, INIA, 28040, Madrid, Spain
| | - Juan Pablo Gutiérrez
- Departamento de Producción Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, 28040, Madrid, Spain
| | - Isabel Cervantes
- Departamento de Producción Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, 28040, Madrid, Spain
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Effects of genotype × environment interaction on the estimation of genetic parameters and gains in Nile tilapia. J Appl Genet 2020; 61:575-580. [PMID: 32815108 DOI: 10.1007/s13353-020-00576-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 07/09/2020] [Accepted: 08/11/2020] [Indexed: 10/23/2022]
Abstract
Nile tilapia (Oreochromis niloticus) is the major fish species produced in Brazil, a country with a vast territory and great climate diversity. This study assessed the effects of the genotype × environment interaction on heritability estimates and selection responses in Nile tilapia (Tilamax strain) cultivated in earthen ponds and net cages. The weight at harvest, trunk length, and head percentage of 4400 individuals were determined. Trait heritabilities were higher in pond fish (0.27-0.52) than in caged fish (0.09-0.33). Genetic correlations between farming systems were lower than 0.5 for the three traits. The rank position of the top 10 families differed according to the environment, as did the response to direct and indirect selection. The results revealed significant genotype × environment effects on the heritability of Nile tilapia farmed under different systems.
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Houston RD, Bean TP, Macqueen DJ, Gundappa MK, Jin YH, Jenkins TL, Selly SLC, Martin SAM, Stevens JR, Santos EM, Davie A, Robledo D. Harnessing genomics to fast-track genetic improvement in aquaculture. Nat Rev Genet 2020; 21:389-409. [PMID: 32300217 DOI: 10.1038/s41576-020-0227-y] [Citation(s) in RCA: 129] [Impact Index Per Article: 32.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/09/2020] [Indexed: 12/12/2022]
Abstract
Aquaculture is the fastest-growing farmed food sector and will soon become the primary source of fish and shellfish for human diets. In contrast to crop and livestock production, aquaculture production is derived from numerous, exceptionally diverse species that are typically in the early stages of domestication. Genetic improvement of production traits via well-designed, managed breeding programmes has great potential to help meet the rising seafood demand driven by human population growth. Supported by continuous advances in sequencing and bioinformatics, genomics is increasingly being applied across the broad range of aquaculture species and at all stages of the domestication process to optimize selective breeding. In the future, combining genomic selection with biotechnological innovations, such as genome editing and surrogate broodstock technologies, may further expedite genetic improvement in aquaculture.
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Affiliation(s)
- Ross D Houston
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Campus, UK.
| | - Tim P Bean
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Campus, UK
| | - Daniel J Macqueen
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Campus, UK
| | - Manu Kumar Gundappa
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Campus, UK
| | - Ye Hwa Jin
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Campus, UK
| | - Tom L Jenkins
- Sustainable Aquaculture Futures, Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | | | | | - Jamie R Stevens
- Sustainable Aquaculture Futures, Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Eduarda M Santos
- Sustainable Aquaculture Futures, Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Andrew Davie
- Institute of Aquaculture, University of Stirling, Stirling, UK
| | - Diego Robledo
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Campus, UK
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9
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Bruijning M, Metcalf CJE, Jongejans E, Ayroles JF. The Evolution of Variance Control. Trends Ecol Evol 2020; 35:22-33. [PMID: 31519463 PMCID: PMC7482585 DOI: 10.1016/j.tree.2019.08.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 08/08/2019] [Accepted: 08/12/2019] [Indexed: 12/12/2022]
Abstract
Genetically identical individuals can be phenotypically variable, even in constant environmental conditions. The ubiquity of this phenomenon, known as 'intra-genotypic variability', is increasingly evident and the relevant mechanistic underpinnings are beginning to be understood. In parallel, theory has delineated a number of formal expectations for contexts in which such a feature would be adaptive. Here, we review empirical evidence across biological systems and theoretical expectations, including nonlinear averaging and bet hedging. We synthesize existing results to illustrate the dependence of selection outcomes both on trait characteristics, features of environmental variability, and species' demographic context. We conclude by discussing ways to bridge the gap between empirical evidence of intra-genotypic variability, studies demonstrating its genetic component, and evidence that it is adaptive.
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Affiliation(s)
- Marjolein Bruijning
- Department of Animal Ecology and Physiology, Radboud University, 6500, GL, Nijmegen, The Netherlands; Department of Ecology and Evolutionary Biology, Princeton University, 08540 Princeton, NJ, USA
| | - C Jessica E Metcalf
- Department of Ecology and Evolutionary Biology, Princeton University, 08540 Princeton, NJ, USA
| | - Eelke Jongejans
- Department of Animal Ecology and Physiology, Radboud University, 6500, GL, Nijmegen, The Netherlands
| | - Julien F Ayroles
- Department of Ecology and Evolutionary Biology, Princeton University, 08540 Princeton, NJ, USA.
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10
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Berghof TVL, Bovenhuis H, Mulder HA. Body Weight Deviations as Indicator for Resilience in Layer Chickens. Front Genet 2019; 10:1216. [PMID: 31921285 PMCID: PMC6923720 DOI: 10.3389/fgene.2019.01216] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 11/04/2019] [Indexed: 02/04/2023] Open
Abstract
Resilience is the capacity of an animal to be minimally affected by disturbances or to rapidly return to the state pertained before exposure to a disturbance. Less resilient animals are expected to be more susceptible to environmental perturbations, such as diseases, and will consequently show more and/or greater fluctuations in production than more resilient animals. Natural antibodies (NAb) are antibodies recognizing antigens without previous exposure to these, and are hypothesized to be an indication of general disease resistance. The objective of this research was to investigate genetic parameters of resilience indicators based on standardized body weight (BW) deviations and to investigate its relation with immunity (i.e. NAb) and disease resistance. Keyhole limpet hemocyanin-binding NAb were measured in layer chickens, which were selectively bred for high and low keyhole limpet hemocyanin-binding NAb levels during six generations. In addition, BW data of these layers were collected on a four-weekly interval from 4 weeks of age until 32 weeks of age. Standardized deviations of BW from an individual were compared to lines’ average BW (i.e. across individuals), and these were used to calculate resilience indicators: natural logarithm-transformed variance [ln(variance)], skewness, and lag-one autocorrelation of deviations (i.e. all within an individual). Heritabilities of resilience indicators were between 0.09 and 0.11. Genetic correlations between the three resilience indicators were between -0.20 and 0.40 (with high SE), which might suggest that the resilience indicators capture different aspects of resilience. Genetic correlations between resilience indicators and NAb were close to zero, which suggests that the resilience indicators and NAb capture different aspects of immunity. This might indicate that, in this dataset, environmental perturbations are only to a small extent affected by disease incidence, possibly due to a lack of disease occurrence. However, a lower estimated breeding value for ln(variance) was predictive for lower lesion scores after an avian pathogenic Escherichia coli inoculation and vice versa. In conclusion, this study shows that there is genetic variation in resilience indicators based on BW deviations in layer chickens, which opens up possibilities to improve resilience by means of selective breeding.
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Affiliation(s)
- Tom V L Berghof
- Wageningen University & Research Animal Breeding and Genomics, Wageningen, Netherlands
| | - Henk Bovenhuis
- Wageningen University & Research Animal Breeding and Genomics, Wageningen, Netherlands
| | - Han A Mulder
- Wageningen University & Research Animal Breeding and Genomics, Wageningen, Netherlands
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11
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Iung LHDS, Carvalheiro R, Neves HHDR, Mulder HA. Genetics and genomics of uniformity and resilience in livestock and aquaculture species: A review. J Anim Breed Genet 2019; 137:263-280. [PMID: 31709657 DOI: 10.1111/jbg.12454] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 10/15/2019] [Accepted: 10/16/2019] [Indexed: 01/29/2023]
Abstract
Genetic control of residual variance offers opportunities to increase uniformity and resilience of livestock and aquaculture species. Improving uniformity and resilience of animals will improve health and welfare of animals and lead to more homogenous products. Our aims in this review were to summarize the current models and methods to study genetic control of residual variance, genetic parameters and genomic results for residual variance and discuss future research directions. Typically, the genetic coefficient of variation is high (median = 0.27; range 0-0.86) and the heritability of residual variance is low (median = 0.01; range 0-0.10). Higher heritabilities can be achieved when increasing the number of records per animal. Divergent selection experiments have supported the feasibility of selecting for high or low residual variance. Genomic studies have revealed associations in regions related to stress, including those from the heat shock protein family. Although the number of studies is growing, genetic control of residual variance is still poorly understood, but big data and genomics offer great opportunities.
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Affiliation(s)
- Laiza Helena de Souza Iung
- School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, Brazil.,CRV Lagoa, Sertãozinho, Brazil
| | - Roberto Carvalheiro
- School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, Brazil.,National Council for Scientific and Technological Development (CNPq), Brasília, Brazil
| | | | - Herman Arend Mulder
- Animal Breeding and Genomics, Wageningen University and Research, Wageningen, The Netherlands
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12
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Tatliyer A, Cervantes I, Formoso-Rafferty N, Gutiérrez JP. The Statistical Scale Effect as a Source of Positive Genetic Correlation Between Mean and Variability: A Simulation Study. G3 (BETHESDA, MD.) 2019; 9:3001-3008. [PMID: 31320386 PMCID: PMC6723139 DOI: 10.1534/g3.119.400497] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 07/16/2019] [Indexed: 12/19/2022]
Abstract
The selection objective for animal production is the highest income with the lowest production cost, while ensuring the highest animal welfare. A selection experiment for environmental variability of birth weight in mice showed a correlated response in the mean after 20 generations starting from a crossed panmictic population. The relationship between the birth weight and its environmental variability explained the correlated response. The scale effect represents a potential cause of this correlation. The relationship between the mean and the variability implies: the higher the mean, the higher the variability. The study was to quantify by simulation the genetic correlation between a trait and its environmental variability. This can be attributable to the scale effect in a range of coefficients of variation and heritabilities between 0.05 and 0.50. The resulting genetic correlation ranged from 0.1335 to 0.7021 being the highest for the highest heritability and the lowest CV. The scale effect for a trait with heritability between 0.25 and 0.35 and CV between 0.15 and 0.25 generated a genetic correlation between 0.43 and 0.57. The genetic coefficient of variation (GCV) affecting residual variability was modulated by the strength reducing the impact of the scale effect. GCV ranged from 0.0050 to 1.4984. The strength of the scale effect might be in the range between 0 and 1. The scale effect would explain many reported genetic correlation and the additive genetic variance for the variability. This is relevant when increasing the mean of a trait jointly with the reduction of its variability.
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Affiliation(s)
- Adile Tatliyer
- Department of Animal Science, Faculty of Agriculture, Kahramanmaras Sutcu Imam University, Avsar Campus, 46100, Onikisubat, Kahramanmaras, Turkey and
| | - Isabel Cervantes
- Department of Animal Production, Faculty of Veterinary, Complutense University of Madrid, Avda. Puerta de Hierro s/n, E-28040-Madrid, Spain
| | - Nora Formoso-Rafferty
- Department of Animal Production, Faculty of Veterinary, Complutense University of Madrid, Avda. Puerta de Hierro s/n, E-28040-Madrid, Spain
| | - Juan Pablo Gutiérrez
- Department of Animal Production, Faculty of Veterinary, Complutense University of Madrid, Avda. Puerta de Hierro s/n, E-28040-Madrid, Spain
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13
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Berghof TVL, Poppe M, Mulder HA. Opportunities to Improve Resilience in Animal Breeding Programs. Front Genet 2019; 9:692. [PMID: 30693014 PMCID: PMC6339870 DOI: 10.3389/fgene.2018.00692] [Citation(s) in RCA: 127] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 12/11/2018] [Indexed: 01/30/2023] Open
Abstract
Resilience is the capacity of an animal to be minimally affected by disturbances or to rapidly return to the state pertained before exposure to a disturbance. However, indicators for general resilience to environmental disturbances have not yet been defined, and perhaps therefore resilience is not yet included in breeding goals. The current developments on big data collection give opportunities to determine new resilience indicators based on longitudinal data, which can aid to incorporate resilience in animal breeding goals. The objectives of this paper were: (1) to define resilience indicator traits based on big data, (2) to define economic values for resilience, and (3) to show the potential to improve resilience of livestock through inclusion of resilience in breeding goals. Resilience might be measured based on deviations from expected production levels over a period of time. Suitable resilience indicators could be the variance of deviations, the autocorrelation of deviations, the skewness of deviations, and the slope of a reaction norm. These (new) resilience indicators provide opportunity to include resilience in breeding programs. Economic values of resilience indicators in the selection index can be calculated based on reduced costs due to labor and treatments. For example, when labor time is restricted, the economic value of resilience increases with an increasing number of animals per farm, and can become as large as the economic value of production. This shows the importance of including resilience in breeding goals. Two scenarios were described to show the additional benefit of including resilience in breeding programs. These examples showed that it is hard to improve resilience with only production traits in the selection index, but that it is possible to greatly improve resilience by including resilience indicators in the selection index. However, when health-related traits are already present in the selection index, the effect is smaller. Nevertheless, inclusion of resilience indicators in the selection index increases the response in the breeding goal and resilience, which results in less labor-demanding, and thus easier-to-manage livestock. Current developments on massive collection of data, and new phenotypes based on these data, offer exciting opportunities to breed for improved resilience of livestock.
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Affiliation(s)
- Tom V. L. Berghof
- Wageningen University & Research Animal Breeding and Genomics, Wageningen, Netherlands
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14
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Iung LHDS, Mulder HA, Neves HHDR, Carvalheiro R. Genomic regions underlying uniformity of yearling weight in Nellore cattle evaluated under different response variables. BMC Genomics 2018; 19:619. [PMID: 30115034 PMCID: PMC6097312 DOI: 10.1186/s12864-018-5003-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 08/08/2018] [Indexed: 02/22/2023] Open
Abstract
BACKGROUND In livestock, residual variance has been studied because of the interest to improve uniformity of production. Several studies have provided evidence that residual variance is partially under genetic control; however, few investigations have elucidated genes that control it. The aim of this study was to identify genomic regions associated with within-family residual variance of yearling weight (YW; N = 423) in Nellore bulls with high density SNP data, using different response variables. For this, solutions from double hierarchical generalized linear models (DHGLM) were used to provide the response variables, as follows: a DGHLM assuming non-null genetic correlation between mean and residual variance (rmv ≠ 0) to obtain deregressed EBV for mean (dEBVm) and residual variance (dEBVv); and a DHGLM assuming rmv = 0 to obtain two alternative response variables for residual variance, dEBVv_r0 and log-transformed variance of estimated residuals (ln_[Formula: see text]). RESULTS The dEBVm and dEBVv were highly correlated, resulting in common regions associated with mean and residual variance of YW. However, higher effects on variance than the mean showed that these regions had effects on the variance beyond scale effects. More independent association results between mean and residual variance were obtained when null rmv was assumed. While 13 and 4 single nucleotide polymorphisms (SNPs) showed a strong association (Bayes Factor > 20) with dEBVv and ln_[Formula: see text], respectively, only suggestive signals were found for dEBVv_r0. All overlapping 1-Mb windows among top 20 between dEBVm and dEBVv were previously associated with growth traits. The potential candidate genes for uniformity are involved in metabolism, stress, inflammatory and immune responses, mineralization, neuronal activity and bone formation. CONCLUSIONS It is necessary to use a strategy like assuming null rmv to obtain genomic regions associated with uniformity that are not associated with the mean. Genes involved not only in metabolism, but also stress, inflammatory and immune responses, mineralization, neuronal activity and bone formation were the most promising biological candidates for uniformity of YW. Although no clear evidence of using a specific response variable was found, we recommend consider different response variables to study uniformity to increase evidence on candidate regions and biological mechanisms behind it.
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Affiliation(s)
- Laiza Helena de Souza Iung
- School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Via de Acesso Prof. Paulo Donato Castelane, S/N, Vila Industrial, FCAV/UNESP, Jaboticabal, São Paulo, 14884-900 Brazil
| | - Herman Arend Mulder
- Wageningen University & Research Animal Breeding and Genomics, P.O. Box 338, 6700 AH Wageningen, The Netherlands
| | | | - Roberto Carvalheiro
- School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Via de Acesso Prof. Paulo Donato Castelane, S/N, Vila Industrial, FCAV/UNESP, Jaboticabal, São Paulo, 14884-900 Brazil
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15
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Abstract
From a physiological-behavioral perspective, it has been shown that fish with a higher density of black eumelanin spots are more dominant, less sensitive to stress, have higher feed intake, better feed efficiency and therefore are larger in size. Thus, we hypothesized that genetic (co)variation between skin pigmentation patterns and growth exists and it is advantageous in rainbow trout. The objective of this study was to determine the genetic relationships between skin pigmentation patterns and BW in a breeding population of rainbow trout. We performed a genetic analysis of pigmentation traits including dorsal color (DC), lateral band (LB) intensity, amount of spotting above (SA) and below (SB) the lateral line, and BW at harvest (HW). Variance components were estimated using a multi-trait linear animal model fitted by restricted maximum likelihood. Estimated heritabilities were 0.08±0.02, 0.17±0.03, 0.44±0.04, 0.17±0.04 and 0.23±0.04 for DC, LB, SA, SB and HW, respectively. Genetic correlations between HW and skin color traits were 0.42±0.13, 0.32±0.14 and 0.25±0.11 for LB, SA and SB, respectively. These results indicate positive, but low to moderate genetic relationships between the amount of spotting and BW in rainbow trout. Thus, higher levels of spotting are genetically associated with better growth performance in this population.
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16
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Agha S, Mekkawy W, Ibanez-Escriche N, Lind CE, Kumar J, Mandal A, Benzie JAH, Doeschl-Wilson A. Breeding for robustness: investigating the genotype-by-environment interaction and micro-environmental sensitivity of Genetically Improved Farmed Tilapia (Oreochromis niloticus). Anim Genet 2018; 49:421-427. [PMID: 30058152 PMCID: PMC6175454 DOI: 10.1111/age.12680] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/09/2018] [Indexed: 12/03/2022]
Abstract
Robustness has become a highly desirable breeding goal in the globalized agricultural market. Both genotype‐by‐environment interaction (G × E) and micro‐environmental sensitivity are important robustness components of aquaculture production, in which breeding stock is often disseminated to different environments. The objectives of this study were (i) to quantify the degree of G × E by assessing the growth performance of Genetically Improved Farmed Tilapia (GIFT) across three countries (Malaysia, India and China) and (ii) to quantify the genetic heterogeneity of environmental variance for body weight at harvest (BW) in GIFT as a measure of micro‐environmental sensitivity. Selection for BW was carried out for 13 generations in Malaysia. Subsets of 60 full‐sib families from Malaysia were sent to China and India after five and nine generations respectively. First, a multi‐trait animal model was used to analyse the BW in different countries as different traits. The results indicate a strong G × E. Second, a genetically structured environmental variance model, implemented using Bayesian inference, was used to analyse micro‐environmental sensitivity of BW in each country. The analysis revealed the presence of genetic heterogeneity of both BW and its environmental variance in all environments. The presence of genetic variation in residual variance of BW implies that the residual variance can be modified by selection. Incorporating both G × E and micro‐environmental sensitivity information may help in selecting robust genotypes with high performance across environments and resilience to environmental fluctuations.
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Affiliation(s)
- S Agha
- The Roslin Institute, The University of Edinburgh, Easter Bush Campus, Midlothian, EH25 9RG, Edinburgh, UK.,Animal Production Department, Faculty of Agriculture, Ain Shams University, Shubra Alkhaima, 11241, Cairo, Egypt
| | - W Mekkawy
- Animal Production Department, Faculty of Agriculture, Ain Shams University, Shubra Alkhaima, 11241, Cairo, Egypt.,WorldFish, Jalan Batu Maung, Batu Maung, Bayan Lepas, 11960, Penang, Malaysia
| | - N Ibanez-Escriche
- The Roslin Institute, The University of Edinburgh, Easter Bush Campus, Midlothian, EH25 9RG, Edinburgh, UK.,Institute for Animal Science and Technology, Universitat Politècnica de València, 46022, València, Spain
| | - C E Lind
- WorldFish, Jalan Batu Maung, Batu Maung, Bayan Lepas, 11960, Penang, Malaysia
| | - J Kumar
- Rajiv Gandhi Center for Aquaculture, Vijayawada, Tamil Nadu, India
| | - A Mandal
- Rajiv Gandhi Center for Aquaculture, Vijayawada, Tamil Nadu, India
| | - J A H Benzie
- WorldFish, Jalan Batu Maung, Batu Maung, Bayan Lepas, 11960, Penang, Malaysia.,School of Biological Earth and Environmental Sciences, University College Cork, North Mall Campus, Cork, Ireland
| | - A Doeschl-Wilson
- The Roslin Institute, The University of Edinburgh, Easter Bush Campus, Midlothian, EH25 9RG, Edinburgh, UK
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17
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Modelling the co-evolution of indirect genetic effects and inherited variability. Heredity (Edinb) 2018; 121:631-647. [PMID: 29588510 PMCID: PMC6221879 DOI: 10.1038/s41437-018-0068-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Revised: 02/10/2018] [Accepted: 02/12/2018] [Indexed: 11/14/2022] Open
Abstract
When individuals interact, their phenotypes may be affected not only by their own genes but also by genes in their social partners. This phenomenon is known as Indirect Genetic Effects (IGEs). In aquaculture species and some plants, however, competition not only affects trait levels of individuals, but also inflates variability of trait values among individuals. In the field of quantitative genetics, the variability of trait values has been studied as a quantitative trait in itself, and is often referred to as inherited variability. Such studies, however, consider only the genetic effect of the focal individual on trait variability and do not make a connection to competition. Although the observed phenotypic relationship between competition and variability suggests an underlying genetic relationship, the current quantitative genetic models of IGE and inherited variability do not allow for such a relationship. The lack of quantitative genetic models that connect IGEs to inherited variability limits our understanding of the potential of variability to respond to selection, both in nature and agriculture. Models of trait levels, for example, show that IGEs may considerably change heritable variation in trait values. Currently, we lack the tools to investigate whether this result extends to variability of trait values. Here we present a model that integrates IGEs and inherited variability. In this model, the target phenotype, say growth rate, is a function of the genetic and environmental effects of the focal individual and of the difference in trait value between the social partner and the focal individual, multiplied by a regression coefficient. The regression coefficient is a genetic trait, which is a measure of cooperation; a negative value indicates competition, a positive value cooperation, and an increasing value due to selection indicates the evolution of cooperation. In contrast to the existing quantitative genetic models, our model allows for co-evolution of IGEs and variability, as the regression coefficient can respond to selection. Our simulations show that the model results in increased variability of body weight with increasing competition. When competition decreases, i.e., cooperation evolves, variability becomes significantly smaller. Hence, our model facilitates quantitative genetic studies on the relationship between IGEs and inherited variability. Moreover, our findings suggest that we may have been overlooking an entire level of genetic variation in variability, the one due to IGEs.
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18
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Nguyen NH, Hamzah A, Thoa NP. Effects of Genotype by Environment Interaction on Genetic Gain and Genetic Parameter Estimates in Red Tilapia ( Oreochromis spp.). Front Genet 2017; 8:82. [PMID: 28659970 PMCID: PMC5468391 DOI: 10.3389/fgene.2017.00082] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 05/30/2017] [Indexed: 11/13/2022] Open
Abstract
The extent to which genetic gain achieved from selection programs under strictly controlled environments in the nucleus that can be expressed in commercial production systems is not well-documented in aquaculture species. The main aim of this paper was to assess the effects of genotype by environment interaction on genetic response and genetic parameters for four body traits (harvest weight, standard length, body depth, body width) and survival in Red tilapia (Oreochromis spp.). The growth and survival data were recorded on 19,916 individual fish from a pedigreed population undergoing three generations of selection for increased harvest weight in earthen ponds from 2010 to 2012 at the Aquaculture Extension Center, Department of Fisheries, Jitra in Kedah, Malaysia. The pedigree comprised a total of 224 sires and 262 dams, tracing back to the base population in 2009. A multivariate animal model was used to measure genetic response and estimate variance and covariance components. When the homologous body traits in freshwater pond and cage were treated as genetically distinct traits, the genetic correlations between the two environments were high (0.85-0.90) for harvest weight and square root of harvest weight but the estimates were of lower magnitudes for length, width and depth (0.63-0.79). The heritabilities estimated for the five traits studied differed between pond (0.02 to 0.22) and cage (0.07 to 0.68). The common full-sib effects were large, ranging from 0.23 to 0.59 in pond and 0.11 to 0.31 in cage across all traits. The direct and correlated responses for four body traits were generally greater in pond than in cage environments (0.011-1.561 vs. -0.033-0.567 genetic standard deviation units, respectively). Selection for increased harvest body weight resulted in positive genetic changes in survival rate in both pond and cage culture. In conclusion, the reduced selection response and the magnitude of the genetic parameter estimates in the production environment (i.e., cage) relative to those achieved in the nucleus (pond) were a result of the genotype by environment interaction and this effect should be taken into consideration in the future breeding program for Red tilapia.
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Affiliation(s)
- Nguyen H Nguyen
- School of Science and Engineering, University of the Sunshine CoastMaroochydore, QLD, Australia
| | - Azhar Hamzah
- National Prawn Fry Production and Research CenterKota Kuala Muda, Malaysia
| | - Ngo P Thoa
- Research Institute for Aquaculture No.1Tu Son, Vietnam
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19
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Iung LHS, Neves HHR, Mulder HA, Carvalheiro R. Genetic control of residual variance of yearling weight in Nellore beef cattle. J Anim Sci 2017; 95:1425-1433. [PMID: 28464101 DOI: 10.2527/jas.2016.1326] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
There is evidence for genetic variability in residual variance of livestock traits, which offers the potential for selection for increased uniformity of production. Different statistical approaches have been employed to study this topic; however, little is known about the concordance between them. The aim of our study was to investigate the genetic heterogeneity of residual variance on yearling weight (YW; 291.15 ± 46.67) in a Nellore beef cattle population; to compare the results of the statistical approaches, the two-step approach and the double hierarchical generalized linear model (DHGLM); and to evaluate the effectiveness of power transformation to accommodate scale differences. The comparison was based on genetic parameters, accuracy of EBV for residual variance, and cross-validation to assess predictive performance of both approaches. A total of 194,628 yearling weight records from 625 sires were used in the analysis. The results supported the hypothesis of genetic heterogeneity of residual variance on YW in Nellore beef cattle and the opportunity of selection, measured through the genetic coefficient of variation of residual variance (0.10 to 0.12 for the two-step approach and 0.17 for DHGLM, using an untransformed data set). However, low estimates of genetic variance associated with positive genetic correlations between mean and residual variance (about 0.20 for two-step and 0.76 for DHGLM for an untransformed data set) limit the genetic response to selection for uniformity of production while simultaneously increasing YW itself. Moreover, large sire families are needed to obtain accurate estimates of genetic merit for residual variance, as indicated by the low heritability estimates (<0.007). Box-Cox transformation was able to decrease the dependence of the variance on the mean and decreased the estimates of genetic parameters for residual variance. The transformation reduced but did not eliminate all the genetic heterogeneity of residual variance, highlighting its presence beyond the scale effect. The DHGLM showed higher predictive ability of EBV for residual variance and therefore should be preferred over the two-step approach.
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20
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Martin JGA, Pirotta E, Petelle MB, Blumstein DT. Genetic basis of between-individual and within-individual variance of docility. J Evol Biol 2017; 30:796-805. [PMID: 28182325 DOI: 10.1111/jeb.13048] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 02/01/2017] [Accepted: 02/02/2017] [Indexed: 11/30/2022]
Abstract
Between-individual variation in phenotypes within a population is the basis of evolution. However, evolutionary and behavioural ecologists have mainly focused on estimating between-individual variance in mean trait and neglected variation in within-individual variance, or predictability of a trait. In fact, an important assumption of mixed-effects models used to estimate between-individual variance in mean traits is that within-individual residual variance (predictability) is identical across individuals. Individual heterogeneity in the predictability of behaviours is a potentially important effect but rarely estimated and accounted for. We used 11 389 measures of docility behaviour from 1576 yellow-bellied marmots (Marmota flaviventris) to estimate between-individual variation in both mean docility and its predictability. We then implemented a double hierarchical animal model to decompose the variances of both mean trait and predictability into their environmental and genetic components. We found that individuals differed both in their docility and in their predictability of docility with a negative phenotypic covariance. We also found significant genetic variance for both mean docility and its predictability but no genetic covariance between the two. This analysis is one of the first to estimate the genetic basis of both mean trait and within-individual variance in a wild population. Our results indicate that equal within-individual variance should not be assumed. We demonstrate the evolutionary importance of the variation in the predictability of docility and illustrate potential bias in models ignoring variation in predictability. We conclude that the variability in the predictability of a trait should not be ignored, and present a coherent approach for its quantification.
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Affiliation(s)
- J G A Martin
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, UK
| | - E Pirotta
- School of Mathematics, Washington State University, Vancouver, WA, USA
| | - M B Petelle
- Department of Zoology and Entomology, University of the Free State Qwaqwa, Phuthaditjhaba, South Africa
| | - D T Blumstein
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA, USA.,The Rocky Mountain Biological Laboratory, Crested Butte, CO, USA
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21
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Sae-Lim P, Kause A, Lillehammer M, Mulder HA. Estimation of breeding values for uniformity of growth in Atlantic salmon (Salmo salar) using pedigree relationships or single-step genomic evaluation. Genet Sel Evol 2017; 49:33. [PMID: 28270100 PMCID: PMC5439168 DOI: 10.1186/s12711-017-0308-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 02/28/2017] [Indexed: 01/22/2023] Open
Abstract
Background In farmed Atlantic salmon, heritability for uniformity of body weight is low, indicating that the accuracy of estimated breeding values (EBV) may be low. The use of genomic information could be one way to increase accuracy and, hence, obtain greater response to selection. Genomic information can be merged with pedigree information to construct a combined relationship matrix (\documentclass[12pt]{minimal}
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\begin{document}$${\mathbf{H}}$$\end{document}H matrix) for a single-step genomic evaluation (ssGBLUP), allowing realized relationships of the genotyped animals to be exploited, in addition to numerator pedigree relationships (\documentclass[12pt]{minimal}
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\begin{document}$${\mathbf{A}}$$\end{document}A matrix). We compared the predictive ability of EBV for uniformity of body weight in Atlantic salmon, when implementing either the \documentclass[12pt]{minimal}
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\begin{document}$${\mathbf{H}}$$\end{document}H matrix in the genetic evaluation. We used double hierarchical generalized linear models (DHGLM) based either on a sire-dam (sire-dam DHGLM) or an animal model (animal DHGLM) for both body weight and its uniformity. Results With the animal DHGLM, the use of \documentclass[12pt]{minimal}
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\begin{document}$${\mathbf{A}}$$\end{document}A significantly increased the correlation between the predicted EBV and adjusted phenotypes, which is a measure of predictive ability, for both body weight and its uniformity (41.1 to 78.1%). When log-transformed body weights were used to account for a scale effect, the use of \documentclass[12pt]{minimal}
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\begin{document}$${\mathbf{A}}$$\end{document}A produced a small and non-significant increase (1.3 to 13.9%) in predictive ability. The sire-dam DHGLM had lower predictive ability for uniformity compared to the animal DHGLM. Conclusions Use of the combined numerator and genomic relationship matrix (\documentclass[12pt]{minimal}
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\begin{document}$${\mathbf{H}}$$\end{document}H) significantly increased the predictive ability of EBV for uniformity when using the animal DHGLM for untransformed body weight. The increase was only minor when using log-transformed body weights, which may be due to the lower heritability of scaled uniformity, the lower genetic correlation of transformed body weight with its uniformity compared to the untransformed traits, and the small number of genotyped animals in the reference population. This study shows that ssGBLUP increases the accuracy of EBV for uniformity of body weight and is expected to increase response to selection in uniformity. Electronic supplementary material The online version of this article (doi:10.1186/s12711-017-0308-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Panya Sae-Lim
- Nofima Ås, Osloveien 1, P.O. Box 210, 1431, Ås, Norway.
| | - Antti Kause
- Biometrical Genetics, Natural Resources Institute Finland, 31600, Jokioinen, Finland
| | | | - Han A Mulder
- Animal Breeding and Genomics Centre, Wageningen University and Research, P.O. Box 338, 6700 AH, Wageningen, The Netherlands
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Janssen K, Berentsen P, Besson M, Komen H. Derivation of economic values for production traits in aquaculture species. Genet Sel Evol 2017; 49:5. [PMID: 28093062 PMCID: PMC5240359 DOI: 10.1186/s12711-016-0278-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 12/05/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In breeding programs for aquaculture species, breeding goal traits are often weighted based on the desired gains but economic gain would be higher if economic values were used instead. The objectives of this study were: (1) to develop a bio-economic model to derive economic values for aquaculture species, (2) to apply the model to determine the economic importance and economic values of traits in a case-study on gilthead seabream, and (3) to validate the model by comparison with a profit equation for a simplified production system. METHODS A bio-economic model was developed to simulate a grow-out farm for gilthead seabream, and then used to simulate gross margin at the current levels of the traits and after one genetic standard deviation change in each trait with the other traits remaining unchanged. Economic values were derived for the traits included in the breeding goal: thermal growth coefficient (TGC), thermal feed intake coefficient (TFC), mortality rate (M), and standard deviation of harvest weight ([Formula: see text]). For a simplified production system, improvement in TGC was assumed to affect harvest weight instead of growing period. Using the bio-economic model and a profit equation, economic values were derived for harvest weight, cumulative feed intake at harvest, and overall survival. RESULTS Changes in gross margin showed that the order of economic importance of the traits was: TGC, TFC, M, and [Formula: see text]. Economic values in € (kg production)-1 (trait unit)-1 were: 0.40 for TGC, -0.45 for TFC, -7.7 for M, and -0.0011 to -0.0010 for [Formula: see text]. For the simplified production system, similar economic values were obtained with the bio-economic model and the profit equation. The advantage of the profit equation is its simplicity, while that of the bio-economic model is that it can be applied to any aquaculture species, because it can include any limiting factor and/or environmental condition that affects production. CONCLUSIONS We confirmed the validity of the bio-economic model. TGC is the most important trait to improve, followed by TFC and M, and the effect of [Formula: see text] on gross margin is small.
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Affiliation(s)
- Kasper Janssen
- Animal Breeding and Genomics, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands.
| | - Paul Berentsen
- Business Economics Group, Wageningen University and Research, Hollandseweg 1, 6706 KN, Wageningen, The Netherlands
| | - Mathieu Besson
- Animal Breeding and Genomics, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands.,Génétique Animale Biologie Intégrative, INRA, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Hans Komen
- Animal Breeding and Genomics, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
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Mulder HA, Gienapp P, Visser ME. Genetic variation in variability: Phenotypic variability of fledging weight and its evolution in a songbird population. Evolution 2016; 70:2004-16. [DOI: 10.1111/evo.13008] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Revised: 06/29/2016] [Accepted: 07/09/2016] [Indexed: 11/29/2022]
Affiliation(s)
- Han A. Mulder
- Animal Breeding and Genomics Centre; Wageningen University and Research; P.O. Box 338, 6700 AH Wageningen The Netherlands
| | - Philip Gienapp
- Animal Breeding and Genomics Centre; Wageningen University and Research; P.O. Box 338, 6700 AH Wageningen The Netherlands
- Department of Animal Ecology; Netherlands Institute of Ecology (NIOO-KNAW); P.O. Box 50, 6700 AB Wageningen The Netherlands
| | - Marcel E. Visser
- Animal Breeding and Genomics Centre; Wageningen University and Research; P.O. Box 338, 6700 AH Wageningen The Netherlands
- Department of Animal Ecology; Netherlands Institute of Ecology (NIOO-KNAW); P.O. Box 50, 6700 AB Wageningen The Netherlands
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24
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Marjanovic J, Mulder HA, Khaw HL, Bijma P. Genetic parameters for uniformity of harvest weight and body size traits in the GIFT strain of Nile tilapia. Genet Sel Evol 2016; 48:41. [PMID: 27286860 PMCID: PMC4901462 DOI: 10.1186/s12711-016-0218-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 05/24/2016] [Indexed: 12/04/2022] Open
Abstract
Background Animal breeding programs have been very successful in improving the mean levels of traits through selection. However, in recent decades, reducing the variability of trait levels between individuals has become a highly desirable objective. Reaching this objective through genetic selection requires that there is genetic variation in the variability of trait levels, a phenomenon known as genetic heterogeneity of environmental (residual) variance. The aim of our study was to investigate the potential for genetic improvement of uniformity of harvest weight and body size traits (length, depth, and width) in the genetically improved farmed tilapia (GIFT) strain. In order to quantify the genetic variation in uniformity of traits and estimate the genetic correlations between level and variance of the traits, double hierarchical generalized linear models were applied to individual trait values. Results Our results showed substantial genetic variation in uniformity of all analyzed traits, with genetic coefficients of variation for residual variance ranging from 39 to 58 %. Genetic correlation between trait level and variance was strongly positive for harvest weight (0.60 ± 0.09), moderate and positive for body depth (0.37 ± 0.13), but not significantly different from 0 for body length and width. Conclusions Our results on the genetic variation in uniformity of harvest weight and body size traits show good prospects for the genetic improvement of uniformity in the GIFT strain. A high and positive genetic correlation was estimated between level and variance of harvest weight, which suggests that selection for heavier fish will also result in more variation in harvest weight. Simultaneous improvement of harvest weight and its uniformity will thus require index selection. Electronic supplementary material The online version of this article (doi:10.1186/s12711-016-0218-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jovana Marjanovic
- Animal Breeding and Genomics Centre, Wageningen University and Research, PO Box 338, 6700 AH, Wageningen, The Netherlands. .,Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Box 7023, 75007, Uppsala, Sweden.
| | - Han A Mulder
- Animal Breeding and Genomics Centre, Wageningen University and Research, PO Box 338, 6700 AH, Wageningen, The Netherlands
| | - Hooi L Khaw
- WorldFish, Jalan Batu Maung, 11960, Bayan Lepas, Penang, Malaysia
| | - Piter Bijma
- Animal Breeding and Genomics Centre, Wageningen University and Research, PO Box 338, 6700 AH, Wageningen, The Netherlands
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25
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Mulder HA, Visscher J, Fablet J. Estimating the purebred-crossbred genetic correlation for uniformity of eggshell color in laying hens. Genet Sel Evol 2016; 48:39. [PMID: 27151311 PMCID: PMC4857450 DOI: 10.1186/s12711-016-0212-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 04/01/2016] [Indexed: 11/30/2022] Open
Abstract
Background Uniformity of eggs is an important aspect for retailers because consumers prefer homogeneous products. One of these characteristics is the color of the eggshell, especially for brown eggs. Existence of a genetic component in environmental variance would enable selection for uniformity of eggshell color. Therefore, the objective of this study was to quantify the genetic variance in environmental variance of eggshell color in purebred and crossbred laying hens, to estimate the genetic correlation between environmental variance of eggshell color in purebred and crossbred laying hens and to estimate genetic correlations between environmental variance at different times of the laying period. Methods We analyzed 167,651 and 79,345 eggshell color records of purebred and crossbred laying hens, respectively. The purebred and crossbred laying hens originated mostly from the same sires. Since eggshell color records of crossbred laying hens were collected per cage, these records could be related only to cage and sire family. A double hierarchical generalized linear sire model was used to estimate the genetic variance of the mean of eggshell color and its environmental variance. Approximate standard errors for heritability and the genetic coefficient of variation for environmental variance were derived. Results The genetic variance in environmental variance at the log scale was equal to 0.077 and 0.067, for purebred and crossbred laying hens, respectively. The genetic coefficient of variation for environmental variance was equal to 0.28 and 0.26, for purebred and crossbred laying hens, respectively. A genetic correlation of 0.70 was found between purebred and crossbred environmental variance of eggshell color, which indicates that there is some reranking of sires for environmental variance of eggshell color in purebred and crossbred laying hens. Genetic correlations between environmental variance of eggshell color in different laying periods were generally higher than 0.85, except between early laying and mid or late laying periods. Conclusions Our results indicate that genetic selection can be efficient to improve uniformity of eggshell color in purebreds and crossbreds, ideally by applying combined crossbred and purebred selection. This methodology can be used to estimate genetic correlations between purebred and crossbred lines for uniformity of other traits and species. Electronic supplementary material The online version of this article (doi:10.1186/s12711-016-0212-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Han A Mulder
- Animal Breeding and Genomics Centre, Wageningen University & Research, PO Box 338, 6700 AH, Wageningen, The Netherlands.
| | - Jeroen Visscher
- Institut de Sélection Animale B.V., Hendrix Genetics, PO Box 114, 5830 AC, Boxmeer, The Netherlands
| | - Julien Fablet
- Institut de Sélection Animale S.A.S., Hendrix Genetics, 22440, Ploufragan, France
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26
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Sell-Kubiak E, Duijvesteijn N, Lopes MS, Janss LLG, Knol EF, Bijma P, Mulder HA. Genome-wide association study reveals novel loci for litter size and its variability in a Large White pig population. BMC Genomics 2015; 16:1049. [PMID: 26652161 PMCID: PMC4674943 DOI: 10.1186/s12864-015-2273-y] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 12/03/2015] [Indexed: 01/11/2023] Open
Abstract
Background In many traits, not only individual trait levels are under genetic control, but also the variation around that level. In other words, genotypes do not only differ in mean, but also in (residual) variation around the genotypic mean. New statistical methods facilitate gaining knowledge on the genetic architecture of complex traits such as phenotypic variability. Here we study litter size (total number born) and its variation in a Large White pig population using a Double Hierarchical Generalized Linear model, and perform a genome-wide association study using a Bayesian method. Results In total, 10 significant single nucleotide polymorphisms (SNPs) were detected for total number born (TNB) and 9 SNPs for variability of TNB (varTNB). Those SNPs explained 0.83 % of genetic variance in TNB and 1.44 % in varTNB. The most significant SNP for TNB was detected on Sus scrofa chromosome (SSC) 11. A possible candidate gene for TNB is ENOX1, which is involved in cell growth and survival. On SSC7, two possible candidate genes for varTNB are located. The first gene is coding a swine heat shock protein 90 (HSPCB = Hsp90), which is a well-studied gene stabilizing morphological traits in Drosophila and Arabidopsis. The second gene is VEGFA, which is activated in angiogenesis and vasculogenesis in the fetus. Furthermore, the genetic correlation between additive genetic effects on TNB and on its variation was 0.49. This indicates that the current selection to increase TNB will also increase the varTNB. Conclusions To the best of our knowledge, this is the first study reporting SNPs associated with variation of a trait in pigs. Detected genomic regions associated with varTNB can be used in genomic selection to decrease varTNB, which is highly desirable to avoid very small or very large litters in pigs. However, the percentage of variance explained by those regions was small. The SNPs detected in this study can be used as indication for regions in the Sus scrofa genome involved in maintaining low variability of litter size, but further studies are needed to identify the causative loci.
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Affiliation(s)
- E Sell-Kubiak
- Animal Breeding and Genomics Center, Wageningen University, P.O. Box 338, 6700, Wageningen, AH, The Netherlands.
| | - N Duijvesteijn
- Topigs Norsvin Research Center B.V, P.O. Box 43, 6640, Beuningen, AA, The Netherlands.
| | - M S Lopes
- Topigs Norsvin Research Center B.V, P.O. Box 43, 6640, Beuningen, AA, The Netherlands.
| | - L L G Janss
- Department of Molecular Biology and Genetics, Aarhus University, P.O. Box 50, 8830, Tjele, Denmark.
| | - E F Knol
- Topigs Norsvin Research Center B.V, P.O. Box 43, 6640, Beuningen, AA, The Netherlands.
| | - P Bijma
- Animal Breeding and Genomics Center, Wageningen University, P.O. Box 338, 6700, Wageningen, AH, The Netherlands.
| | - H A Mulder
- Animal Breeding and Genomics Center, Wageningen University, P.O. Box 338, 6700, Wageningen, AH, The Netherlands.
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Sae-Lim P, Mulder H, Gjerde B, Koskinen H, Lillehammer M, Kause A. Genetics of Growth Reaction Norms in Farmed Rainbow Trout. PLoS One 2015; 10:e0135133. [PMID: 26267268 PMCID: PMC4534094 DOI: 10.1371/journal.pone.0135133] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 07/18/2015] [Indexed: 11/19/2022] Open
Abstract
Rainbow trout is farmed globally under diverse uncontrollable environments. Fish with low macroenvironmental sensitivity (ES) of growth is important to thrive and grow under these uncontrollable environments. The ES may evolve as a correlated response to selection for growth in one environment when the genetic correlation between ES and growth is nonzero. The aims of this study were to quantify additive genetic variance for ES of body weight (BW), defined as the slope of reaction norm across breeding environment (BE) and production environment (PE), and to estimate the genetic correlation (rg(int, sl)) between BW and ES. To estimate heritable variance of ES, the coheritability of ES was derived using selection index theory. The BW records from 43,040 rainbow trout performing either in freshwater or seawater were analysed using a reaction norm model. High additive genetic variance for ES (9584) was observed, inferring that genetic changes in ES can be expected. The coheritability for ES was either -0.06 (intercept at PE) or -0.08 (intercept at BE), suggesting that BW observation in either PE or BE results in low accuracy of selection for ES. Yet, the rg(int, sl) was negative (-0.41 to -0.33) indicating that selection for BW in one environment is expected to result in more sensitive fish. To avoid an increase of ES while selecting for BW, it is possible to have equal genetic gain in BW in both environments so that ES is maintained stable.
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Affiliation(s)
- Panya Sae-Lim
- Aquaculture and Genetics, Nofima, Osloveien 1, Ås, Norway
- * E-mail:
| | - Han Mulder
- Animal Breeding and Genomics Centre, Wageningen University, Wageningen, the Netherlands
| | - Bjarne Gjerde
- Aquaculture and Genetics, Nofima, Osloveien 1, Ås, Norway
| | - Heikki Koskinen
- Aquaculture Unit, Natural Resources Institute Finland, Tervo, Finland
| | | | - Antti Kause
- Biometrical Genetics, Natural Resources Institute Finland, Jokioinen, Finland
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