1
|
Bayomy MFF, Hassab El-Nabi SE, El Kassas TA, Attia ZI, Saeed AM, Taha HSA, Alagawany M, Galosi L, Biagini L, El-Kassas S. Extender Supplementation with Glutathione (GSH) and Taurine Improves In Vitro Sperm Quality and Antioxidant Status of New Zealand Rabbits during Chilled Storage for up to 72 hours. Vet Med Int 2023; 2023:8339591. [PMID: 37732161 PMCID: PMC10509003 DOI: 10.1155/2023/8339591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 08/26/2023] [Accepted: 08/30/2023] [Indexed: 09/22/2023] Open
Abstract
This study assessed the influence of supplementing the rabbit semen extender with various concentrations of glutathione (GSH) and taurine at 24, 48, and 72 h postchilling at 5°C. Semen samples were collected from 20 New Zealand bucks, and ejaculates with standard color, motility (>85%), about 0.5 mL volume, and ∼400 × 106/mL concentration were used and diluted with extenders supplemented with 0.5, 1, and 2 mM of GSH and 1, 5, and 10 mM of taurine and chilled at 5°C. Nonsupplemented samples were used as a control. Sperm's progressive motility, acrosome reaction, and extracellular oxidative stress biomarkers such as MDA contents and GPx, SOD, and CAT concentrations and intracellular transcriptomic levels of SOD and CAT genes were assessed. GSH and taurine supplementation improved the sperm's kinetics by reducing cooling-associated stress, which was ascertained by lowering MDA concentration and increasing SOD, CAT, and GPx concentrations (P < 0.05). Increasing the levels of antioxidant enzymes in the extender was due to the increasing mRNA copies of the SOD and CAT genes (P < 0.05). Furthermore, GSH and taurine maintained the fructose levels in the extender and lowered the GPT levels, which implies sperm membrane stability is maintained through GSH and taurine supplementation. GSH and taurine supplementation to the extender had protective influences on the in vitro rabbit semen quality during chilled storage for up to 72 h, which were remarkable with increasing supplementation dose and cooling time at 5°C.
Collapse
Affiliation(s)
- Mohamed F. F. Bayomy
- Zoology Department, Faculty of Science, Menoufia University, Shibin Al Kawm, Egypt
- General Biology Department, Center of the Basic Sciences, Misr University for Science and Technology (MUST), 6th of October City, Egypt
| | | | - Tahany A. El Kassas
- Zoology Department, Faculty of Science, Menoufia University, Shibin Al Kawm, Egypt
| | - Zeinab I. Attia
- Zoology Department, Faculty of Science, Tanta University, Tanta, Egypt
| | - Ayman M. Saeed
- Biotechnology Department, Animal Production Research Institute, Giza, Egypt
| | - Heba S. A. Taha
- Department of Genetics, Faculty of Agriculture, Zagazig University, Zagazig, Egypt
| | - Mahmoud Alagawany
- Poultry Department, Agriculture Faculty, Zagazig University, Zagazig 44519, Egypt
| | - Livio Galosi
- School of Bioscience and Veterinary Medicine, University of Camerino, Matelica 62024, Italy
| | - Lucia Biagini
- School of Bioscience and Veterinary Medicine, University of Camerino, Matelica 62024, Italy
| | - Seham El-Kassas
- Animal, Poultry, and Fish Breeding and Production, Department of Animal Wealth Development, Faculty of Veterinary Medicine, Kafrelsheikh University, Kafr el-Sheikh, Egypt
| |
Collapse
|
2
|
How Depressing Is Inbreeding? A Meta-Analysis of 30 Years of Research on the Effects of Inbreeding in Livestock. Genes (Basel) 2021; 12:genes12060926. [PMID: 34207101 PMCID: PMC8234567 DOI: 10.3390/genes12060926] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 06/12/2021] [Accepted: 06/15/2021] [Indexed: 11/17/2022] Open
Abstract
Inbreeding depression has been widely documented for livestock and other animal and plant populations. Inbreeding is generally expected to have a stronger unfavorable effect on fitness traits than on other traits. Traditionally, the degree of inbreeding depression in livestock has been estimated as the slope of the linear regression of phenotypic values on pedigree-based inbreeding coefficients. With the increasing availability of SNP-data, pedigree inbreeding can now be replaced by SNP-based measures. We performed a meta-analysis of 154 studies, published from 1990 to 2020 on seven livestock species, and compared the degree of inbreeding depression (1) across different trait groups, and (2) across different pedigree-based and SNP-based measures of inbreeding. Across all studies and traits, a 1% increase in pedigree inbreeding was associated with a median decrease in phenotypic value of 0.13% of a trait’s mean, or 0.59% of a trait’s standard deviation. Inbreeding had an unfavorable effect on all sorts of traits and there was no evidence for a stronger effect on primary fitness traits (e.g., reproduction/survival traits) than on other traits (e.g., production traits or morphological traits). p-values of inbreeding depression estimates were smaller for SNP-based inbreeding measures than for pedigree inbreeding, suggesting more power for SNP-based measures. There were no consistent differences in p-values for percentage of homozygous SNPs, inbreeding based on runs of homozygosity (ROH) or inbreeding based on a genomic relationship matrix. The number of studies that directly compares these different measures, however, is limited and comparisons are furthermore complicated by differences in scale and arbitrary definitions of particularly ROH-based inbreeding. To facilitate comparisons across studies in future, we provide the dataset with inbreeding depression estimates of 154 studies and stress the importance of always reporting detailed information (on traits, inbreeding coefficients, and models used) along with inbreeding depression estimates.
Collapse
|
3
|
Nishijima K, Kitajima S, Matsuhisa F, Niimi M, Wang CC, Fan J. Strategies for Highly Efficient Rabbit Sperm Cryopreservation. Animals (Basel) 2021; 11:ani11051220. [PMID: 33922622 PMCID: PMC8145333 DOI: 10.3390/ani11051220] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/20/2021] [Accepted: 04/21/2021] [Indexed: 12/28/2022] Open
Abstract
The rabbit is a valuable animal for both the economy and biomedical sciences. Sperm cryopreservation is one of the most efficient ways to preserve rabbit strains because it is easy to collect ejaculate repeatedly from a single male and inseminate artificially into multiple females. During the cooling, freezing and thawing process of sperms, the plasma membrane, cytoplasm and genome structures could be damaged by osmotic stress, cold shock, intracellular ice crystal formation, and excessive production of reactive oxygen species. In this review, we will discuss the progress made during the past years regarding efforts to minimize the cell damage in rabbit sperms, including freezing extender, cryoprotectants, supplements, and procedures.
Collapse
Affiliation(s)
- Kazutoshi Nishijima
- Center for Animal Resources and Collaborative Study, National Institutes of Natural Sciences, 38 Nishigonaka, Myodaiji, Okazaki 444-8585, Japan
- National Institute for Physiological Sciences, National Institutes of Natural Sciences, 38 Nishigonaka, Myodaiji, Okazaki 444-8585, Japan
- Department of Physiological Sciences, SOKENDAI (The Graduate University for Advanced Studies), Aichi, Okazaki 444-8585, Japan
- Correspondence: (K.N.); (J.F.); Tel.: +81-564-557781 (K.N.); +81-55-2739519 (J.F.)
| | - Shuji Kitajima
- Analytical Research Center for Experimental Sciences, Division of Biological Resources and Development, Saga University, 5-1-1 Nabeshima, Saga 849-8501, Japan; (S.K.); (F.M.)
| | - Fumikazu Matsuhisa
- Analytical Research Center for Experimental Sciences, Division of Biological Resources and Development, Saga University, 5-1-1 Nabeshima, Saga 849-8501, Japan; (S.K.); (F.M.)
| | - Manabu Niimi
- Department of Molecular Pathology, Faculty of Medicine, Interdisciplinary Graduate School of Medical Sciences, University of Yamanashi, 1110 Shimokato, Chuo 409-3898, Japan;
| | - Chen-chi Wang
- Animal Resources Section, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami-gun, Okinawa 904-0495, Japan;
| | - Jianglin Fan
- Department of Molecular Pathology, Faculty of Medicine, Interdisciplinary Graduate School of Medical Sciences, University of Yamanashi, 1110 Shimokato, Chuo 409-3898, Japan;
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529020, China
- Correspondence: (K.N.); (J.F.); Tel.: +81-564-557781 (K.N.); +81-55-2739519 (J.F.)
| |
Collapse
|
4
|
Sheikhlou M, Badereh S, Bahri Binabaj F. Assessment of between-founder heterogeneity in inbreeding depression for reproductive traits in Baluchi sheep. Anim Reprod Sci 2020; 221:106593. [PMID: 32931988 DOI: 10.1016/j.anireprosci.2020.106593] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 08/29/2020] [Accepted: 08/31/2020] [Indexed: 10/23/2022]
Abstract
Magnitude of inbreeding depression could be different among descendants of various founder animals, when recessive genetic composition of a population is unevenly distributed among founder animal genomes. Reproductive records of Baluchi sheep for the litter variables size at birth (LSB), size at weaning (LSW), mean weight/lamb born (LMWLB), mean weight/lamb weaned (LMWLW), total weight at birth/ewe lambing (TLWB) and total weight at weaning/ewe lambing (TLWW) were used to examine heterogeneity in inbreeding depression between founder animals. Pedigree-based inbreeding coefficients were proportioned into components coming from founder animals and Mendellian contribution from non-founder animals. Two approaches were used to assess effects of inbreeding: overall inbreeding coefficients or partial inbreeding of the four main founder animals as possible covariates included in statistical models. Among the traits evaluated, there were effects on LMWLB, LMWLW and TLWW of inbreeding with there being a -8, -48, and -95 g decrease per 1% increase in inbreeding, respectively. Linear regressions of traits on partial inbreeding coefficients due to founder animals were of different magnitudes and ranged between -0.12 and +0.128. Heterogeneous contribution of founder animals to inbreeding depression occurred for LSB, LMWLB, and TLWW. These results indicate there was uneven distribution of recessive genetic composition among genomes of founder animals or differences in selection pressures on unfavorable alleles between different founder lines. The observed variation in founder-specific inbreeding depression indicates a small number of alleles with major effects are contributing to inbreeding depression.
Collapse
Affiliation(s)
- Mohammadreza Sheikhlou
- Department of Animal Science, Ahar Faculty of Agriculture and Natural Resources, University of Tabriz, Ahar, Iran.
| | - Solmaz Badereh
- MSc Graduate of Animal Breeding and Genetics, Ahar Faculty of Agriculture and Natural Resources, University of Tabriz, Ahar, Iran
| | - Fateme Bahri Binabaj
- Department of Animal Science, College of Agriculture and Natural Resources, Gonbad Kavous University, Gonbad Kavous, Iran
| |
Collapse
|
5
|
Varona L, Altarriba J, Moreno C, Martínez-Castillero M, Casellas J. A multivariate analysis with direct additive and inbreeding depression load effects. Genet Sel Evol 2019; 51:78. [PMID: 31878872 PMCID: PMC6933709 DOI: 10.1186/s12711-019-0521-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 12/17/2019] [Indexed: 11/16/2022] Open
Abstract
Background Inbreeding is caused by mating between related individuals and its most common consequence is inbreeding depression. Several studies have detected heterogeneity in inbreeding depression among founder individuals, and recently a procedure for predicting hidden inbreeding depression loads associated with founders and the Mendelian sampling of non-founders has been developed. The objectives of our study were to expand this model to predict the inbreeding loads for all individuals in the pedigree and to estimate the covariance between the inbreeding loads and the additive genetic effects for the trait of interest. We tested the proposed approach with simulated data and with two datasets of records on weaning weight from the Spanish Pirenaica and Rubia Gallega beef cattle breeds. Results The posterior estimates of the variance components with the simulated datasets did not differ significantly from the simulation parameters. In addition, the correlation between the predicted and simulated inbreeding loads were always positive and ranged from 0.27 to 0.82. The beef cattle datasets comprised 35,126 and 75,194 records on weights between 170 and 250 days of age, and pedigrees of 308,836 and 384,434 individual-sire-dam entries for the Pirenaica and Rubia Gallega breeds, respectively. The posterior mean estimates of the variance of inbreeding depression loads were 29,967.8 and 28,222.4 for the Pirenaica and Rubia Gallega breeds, respectively. They were larger than those of the additive variance (695.0 and 439.8 for Pirenaica and Rubia Gallega, respectively), because they should be understood as the variance of the inbreeding depression achieved by a fully inbred (100%) descendant. Therefore, the inbreeding loads have to be rescaled for smaller inbreeding coefficients. In addition, a strong negative correlation (− 0.43 ± 0.10) between additive effects and inbreeding loads was detected in the Pirenaica, but not in the Rubia Gallega breed. Conclusions The results of the simulation study confirmed the ability of the proposed procedure to predict inbreeding depression loads for all individuals in the populations. Furthermore, the results obtained from the two real datasets confirmed the variability in the inbreeding depression loads in both breeds and suggested a negative correlation of the inbreeding loads with the additive genetic effects in the Pirenaica breed.
Collapse
Affiliation(s)
- Luis Varona
- Departamento de Anatomía Embriología y Genética Animal, Instituto Agroalimentario de Aragón (IA2), Universidad de Zaragoza, 50013, Saragossa, Spain.
| | - Juan Altarriba
- Departamento de Anatomía Embriología y Genética Animal, Instituto Agroalimentario de Aragón (IA2), Universidad de Zaragoza, 50013, Saragossa, Spain
| | - Carlos Moreno
- Departamento de Anatomía Embriología y Genética Animal, Instituto Agroalimentario de Aragón (IA2), Universidad de Zaragoza, 50013, Saragossa, Spain
| | - María Martínez-Castillero
- Dipartimento di Agronomia Animali, Alimenti Risorce Naturali e Ambiente, Università degli Studi di Padova, 35122, Padua, Italy
| | - Joaquim Casellas
- Departament de Ciència Animal i dels Aliments, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain
| |
Collapse
|
6
|
Matsuda Y, Shibata Y, Basaki K, Fukuda Y, Takaki N, Maeda T, Hirao M, Yano M, Higashiya M, Obata T, Seki S, Nishijima K. Characteristic features of newly established specific pathogen-free albino large rabbit (JW-AKT): Comparison with Japanese White and New Zealand White rabbits. J Vet Med Sci 2019; 81:739-743. [PMID: 30918135 PMCID: PMC6541839 DOI: 10.1292/jvms.18-0758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The present study was conducted to reveal characteristic features of albino large rabbit (JW-AKT) which we formerly established a specific pathogen-free (SPF) colony. Body weights of JW-AKT rabbit at 52 weeks old was 5.7 ± 0.4 kg in males and 6.4 ± 0.4 kg in females. Weight of body, heart, lung and kidney in JW-AKT rabbit was significantly higher than in Japanese white and New Zealand white rabbits in both sexes. Though the body weight (BW) was rather lower in males, body length and brain weights tended to be higher in males than in females. Since body fat was significantly higher in females, what affects difference in BW is body fat, rather than the physical constitution of female JW-AKT rabbit. No critical sex difference was found in hematological parameters in JW-AKT rabbit. The results indicated that JW-AKT were about 1.5 times larger than the general laboratory rabbits with common properties in hematology. Thus, JW-AKT rabbit could be used as a novel SPF experimental animal model with some advantages in surgical experiments or collection of large amount of biological specimen.
Collapse
Affiliation(s)
- Yukihisa Matsuda
- Animal Research Laboratory, Bioscience Education-Research Support Center, Akita University, 1-1-1 Hondo, Akita 010-8543 Japan
| | - Yoshiko Shibata
- Animal Research Laboratory, Bioscience Education-Research Support Center, Akita University, 1-1-1 Hondo, Akita 010-8543 Japan
| | - Keita Basaki
- Animal Research Laboratory, Bioscience Education-Research Support Center, Akita University, 1-1-1 Hondo, Akita 010-8543 Japan
| | - Yasuyoshi Fukuda
- Animal Research Laboratory, Bioscience Education-Research Support Center, Akita University, 1-1-1 Hondo, Akita 010-8543 Japan
| | - Naofumi Takaki
- Kitayama Labes Co., Ltd., 8046-1 Nishiminowa, Ina, Nagano 399-4501 Japan
| | - Tatsuhiro Maeda
- Kitayama Labes Co., Ltd., 8046-1 Nishiminowa, Ina, Nagano 399-4501 Japan
| | - Masao Hirao
- Kitayama Labes Co., Ltd., 8046-1 Nishiminowa, Ina, Nagano 399-4501 Japan
| | - Megumi Yano
- Animal Research Laboratory, Bioscience Education-Research Support Center, Akita University, 1-1-1 Hondo, Akita 010-8543 Japan
| | - Misako Higashiya
- Animal Research Laboratory, Bioscience Education-Research Support Center, Akita University, 1-1-1 Hondo, Akita 010-8543 Japan
| | - Takahiro Obata
- Animal Research Laboratory, Bioscience Education-Research Support Center, Akita University, 1-1-1 Hondo, Akita 010-8543 Japan
| | - Shinsuke Seki
- Animal Research Laboratory, Bioscience Education-Research Support Center, Akita University, 1-1-1 Hondo, Akita 010-8543 Japan
| | - Kazutoshi Nishijima
- Animal Research Laboratory, Bioscience Education-Research Support Center, Akita University, 1-1-1 Hondo, Akita 010-8543 Japan
| |
Collapse
|
7
|
Casellas J. On individual-specific prediction of hidden inbreeding depression load. J Anim Breed Genet 2017; 135:37-44. [PMID: 29230876 DOI: 10.1111/jbg.12308] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 11/17/2017] [Indexed: 11/29/2022]
Abstract
Inbreeding depression is caused by increased homozygosity in the genome and merges two genetic mechanisms, a higher impact from recessive mutations and the waste of overdominance contributions. It is of major concern for the conservation of endangered populations of plants and animals, as major abnormalities are more frequent in inbred families than in outcrosses. Nevertheless, we lack appropriate analytical methods to estimate the hidden inbreeding depression load (IDL) in the genome of each individual. Here, a new mixed linear model approach has been developed to account for the inbreeding depression-related background of each individual in the pedigree. Within this context, inbred descendants contributed relevant information to predict the IDL contained in the genome of a given ancestor; moreover, known relationships spread these predictions to the remaining individuals in the pedigree, even if not contributing inbred offspring. Results obtained from the analysis of weaning weight in the MARET rabbit population demonstrated that the genetic background of inbreeding depression distributed heterogeneously across individuals and inherited generation by generation. Moreover, this approach was clearly preferred in terms of model fit and complexity when compared with classical approaches to inbreeding depression. This methodology must be viewed as a new tool for a better understanding of inbreeding in domestic and wild populations.
Collapse
Affiliation(s)
- J Casellas
- Grup de Recerca en Millora Genètica Molecular Veterinària, Departament de Ciència Animal i dels Aliments, Universitat Autònoma de Barcelona, Bellaterra, Spain
| |
Collapse
|
8
|
Leroy G. Inbreeding depression in livestock species: review and meta-analysis. Anim Genet 2014; 45:618-28. [PMID: 24975026 DOI: 10.1111/age.12178] [Citation(s) in RCA: 133] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/01/2014] [Indexed: 12/16/2022]
Abstract
Inbreeding, by virtue of its consequence on traits of interest, is a topic of major interest for geneticists and animal breeders. Based on meta-analysis conducted on 57 studies and seven livestock species considering a wide variety of selected traits, it was estimated that inbreeding depression corresponds to on average a decrease of 0.137 percent of the mean of a trait per 1 percent of inbreeding. The decrease was larger for production traits (reduction of 0.351%) than for other trait categories. For populations raised as purebreds, inbreeding depression may impact the economic income of breeders. There is a need for studies assessing the existence of an inbreeding purge phenomenon as well as the impact of inbreeding on adaptation capacities of livestock species. Promises brought by the development of dense genotyping as well as functional genomics will increase the capacities to improve our understanding and management of the phenomenon.
Collapse
Affiliation(s)
- G Leroy
- AgroParisTech, UMR 1313 Génétique Animale et Biologie Intégrative, F-75231, Paris, France; INRA, UMR 1313 Génétique Animale et Biologie Intégrative, F-78352, Jouy-en-Josas, France
| |
Collapse
|
9
|
Fina M, Ibáñez-Escriche N, Piedrafita J, Casellas J. Canalization analysis of birth weight in Bruna dels Pirineus beef cattle. J Anim Sci 2013; 91:3070-8. [PMID: 23658344 DOI: 10.2527/jas.2012-5675] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Although heteroskedasticity has been a main topic of interest in beef cattle during recent decades, the current availability of canalization models provided new insights for animal breeding programs. Within this context, birth BW (BWT) was analyzed in the Bruna dels Pirineus beef cattle breed by implementing canalization models that accounted for heterogeneous residual variances due to systematic, permanent environmental effects and additive genetic effects. Analyses were performed on BWT data from 8,130 calves born in 12 commercial breeding herds contributing to the yield recording scheme of the Bruna dels Pirineus breed. Analytical models accounted for direct additive genetic, permanent environmental, and 4 systematic effects (i.e., age of the dam, sex of the calf, birth type, and herd-year-season), and the same effects were evaluated as potential sources of variation in the residual term. Their relevance was checked by the deviance information criterion (DIC), and only residual additive genetic, permanent environmental, birth type, and herd-year-season remained in the operational model, all of them originating relevant reductions in the DIC parameter. Bruna dels Pirineus calves showed a moderate heritability of 0.30 (95% high posterior density, 0.19 to 0.40) for BWT; additional additive genetic variability was revealed in the residual term, this being positively correlated with the direct additive genetic component (0.44; 95% high posterior density, 0.37 to 0.54). Genetic trends were evaluated on both sources of additive genetic variance, and relevant patterns were identified in several herds. Although this breed did not evidence a homogeneous genetic trend for the whole population, herd-specific positive and negative trends were revealed, suggesting the plausibility of genetic selection for canalization on BWT in beef cattle breeds. These results must be viewed as a contribution to the canalization research field, providing relevant information for the breeding scheme of the Bruna dels Pirineus breed, as well as important insights about the genetic background of BWT for the beef industry worldwide.
Collapse
Affiliation(s)
- M Fina
- Grup de Recerca en Remugants, Departament de Ciència Animal i dels Aliments, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | | | | | | |
Collapse
|
10
|
Reed DH, Fox CW, Enders LS, Kristensen TN. Inbreeding-stress interactions: evolutionary and conservation consequences. Ann N Y Acad Sci 2012; 1256:33-48. [PMID: 22583046 DOI: 10.1111/j.1749-6632.2012.06548.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The effect of environmental stress on the magnitude of inbreeding depression has a long history of intensive study. Inbreeding-stress interactions are of great importance to the viability of populations of conservation concern and have numerous evolutionary ramifications. However, such interactions are controversial. Several meta-analyses over the last decade, combined with omic studies, have provided considerable insight into the generality of inbreeding-stress interactions, its physiological basis, and have provided the foundation for future studies. In this review, we examine the genetic and physiological mechanisms proposed to explain why inbreeding-stress interactions occur. We specifically examine whether the increase in inbreeding depression with increasing stress could be due to a concomitant increase in phenotypic variation, using a larger data set than any previous study. Phenotypic variation does usually increase with stress, and this increase can explain some of the inbreeding-stress interaction, but it cannot explain all of it. Overall, research suggests that inbreeding-stress interactions can occur via multiple independent channels, though the relative contribution of each of the mechanisms is unknown. To better understand the causes and consequences of inbreeding-stress interactions in natural populations, future research should focus on elucidating the genetic architecture of such interactions and quantifying naturally occurring levels of stress in the wild.
Collapse
Affiliation(s)
- David H Reed
- Department of Biology, University of Louisville, Louisville, Kentucky, USA
| | | | | | | |
Collapse
|