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1.
BMC Genomics ; 25(1): 487, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38755557

RESUMEN

BACKGROUND: The identification of low-frequency haplotypes, never observed in homozygous state in a population, is considered informative on the presence of potentially harmful alleles (candidate alleles), putatively involved in inbreeding depression. Although identification of candidate alleles is challenging, studies analyzing the dynamics of potentially harmful alleles are lacking. A pedigree of the highly endangered Gochu Asturcelta pig breed, including 471 individuals belonging to 51 different families with at least 5 offspring each, was genotyped using the Axiom PigHDv1 Array (658,692 SNPs). Analyses were carried out on four different cohorts defined according to pedigree depth and at the whole population (WP) level. RESULTS: The 4,470 Linkage Blocks (LB) identified in the Base Population (10 individuals), gathered a total of 16,981 alleles in the WP. Up to 5,466 (32%) haplotypes were statistically considered candidate alleles, 3,995 of them (73%) having one copy only. The number of alleles and candidate alleles varied across cohorts according to sample size. Up to 4,610 of the alleles identified in the WP (27% of the total) were present in one cohort only. Parentage analysis identified a total of 67,742 parent-offspring incompatibilities. The number of mismatches varied according to family size. Parent-offspring inconsistencies were identified in 98.2% of the candidate alleles and 100% of the LB in which they were located. Segregation analyses informed that most potential candidate alleles appeared de novo in the pedigree. Only 17 candidate alleles were identified in the boar, sow, and paternal and maternal grandparents and were considered segregants. CONCLUSIONS: Our results suggest that neither mutation nor recombination are the major forces causing the apparition of candidate alleles. Their occurrence is more likely caused by Allele-Drop-In events due to SNP calling errors. New alleles appear when wrongly called SNPs are used to construct haplotypes. The presence of candidate alleles in either parents or grandparents of the carrier individuals does not ensure that they are true alleles. Minimum Allele Frequency thresholds may remove informative alleles. Only fully segregant candidate alleles should be considered potentially harmful alleles. A set of 16 candidate genes, potentially involved in inbreeding depression, is described.


Asunto(s)
Alelos , Haplotipos , Linaje , Polimorfismo de Nucleótido Simple , Animales , Porcinos/genética , Dinámica Poblacional , Femenino , Masculino , Frecuencia de los Genes
2.
J Anim Breed Genet ; 141(2): 193-206, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37990938

RESUMEN

Runs of homozygosity (ROH) are defined as long continuous homozygous stretches in the genome which are assumed to originate from a common ancestor. It has been demonstrated that divergent selection for variability in mice is possible and that low variability in birth weight is associated with robustness. To analyse ROH patterns and ROH-based genomic inbreeding, two mouse lines that were divergently selected for birth weight variability for 26 generations were used, with: 752 individuals for the high variability line (H-Line), 766 individuals for the low variability line (L-Line) and 74 individuals as a reference population. Individuals were genotyped using the high density Affymetrix Mouse Diversity Genotyping Array. ROH were identified using both the sliding windows (SW) and the consecutive runs (CR) methods. Inbreeding coefficients were calculated based on pedigree (FPED ) information, on ROH identified using the SW method (FROHSW ) and on ROH identified using the CR method (FROHCR ). Differences in genomic inbreeding were not consistent across generations and these parameters did not show clear differences between lines. Correlations between FPED and FROH were high, particularly for FROHSW . Moreover, correlations between FROHSW and FPED were even higher when ROH were identified with no restrictions in the number of heterozygotes per ROH. The comparison of FROH estimates between either of the selected lines were based on significant differences at the chromosome level, mainly in chromosomes 3, 4, 6, 8, 11, 15 and 19. ROH-based inbreeding estimates that were computed using longer homozygous segments had a higher relationship with FPED . Differences in robustness between lines were not attributable to a higher homozygosis in the L-Line, but maybe to the different distribution of ROH at the chromosome level between lines. The analysis identified a set of genomic regions for future research to establish the genomic basis of robustness.


Asunto(s)
Genoma , Endogamia , Animales , Ratones , Peso al Nacer , Homocigoto , Genotipo , Genoma/genética , Polimorfismo de Nucleótido Simple
3.
J Anim Breed Genet ; 2024 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-38404110

RESUMEN

The quality of alpaca textile fibre has great potential, especially if objectionable fibres (coarse and medullated fibres) that cause itching are reduced, considering that objectionable fibres can be identified by diameter and medullation types. The objective of this study was to estimate genetic parameters for medullar types and their respective diameters to evaluate the possibility of incorporating them as selection criteria in alpaca breeding programmes. The research used 3149 alpaca fibre samples collected from 2020 to 2022, from a population of 1626 Huacaya type alpacas. The heritability and correlations of the percentages of non-medullated (NM), fragmented medulle (FM), uncontinuous medullated (UM), continuous medullated (CM), and strongly medullated (SM) fibres were analysed, also the fibre diameter (FD) for each of the medullation types. The heritability estimated for medullation types were 0.25 ± 0.01, 0.18 ± 0.01, 0.10 ± 0.01, 0.20 ± 0.01 and 0.11 ± 0.01 for NM, FM, UM, CM and SM, respectively. The genetic correlations for medullation categories ranged from 0.15 ± 0.03 to 0.66 ± 0.02 (in absolute values). The heritabilility estimated for fibre diameter (FD) of each of the medullation types were 0.29 ± 0.03, 0.27 ± 0.02, 0.35 ± 0.02, 0.30 ± 0.02, 0.25 ± 0.02 and 0.10 ± 0.02 for FD, FD_NM, FD_FM, FD_UM, FD_CM and FD_SM, respectively. The genetic correlations for fibre diameter of the medullation types ranged from 0.04 ± 0.04 to 0.97 ± 0.01. FD, NM and FM are the main traits to be used as selection criteria under a genetic index, since they would reduce fibre diameter, and also increase NM and FM, and, in addition reducing indirectly CM, SM, and SM_FD. Therefore, the quality of alpaca fibre could be improved.

4.
Genet Sel Evol ; 55(1): 74, 2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37880572

RESUMEN

BACKGROUND: In spite of the availability of single nucleotide polymorphism (SNP) array data, differentiation between observed homozygosity and that caused by mating between relatives (autozygosity) introduces major difficulties. Homozygosity estimators show large variation due to different causes, namely, Mendelian sampling, population structure, and differences among chromosomes. Therefore, the ascertainment of how inbreeding is reflected in the genome is still an issue. The aim of this research was to study the usefulness of genomic information for the assessment of genetic diversity in the highly endangered Gochu Asturcelta pig breed. Pedigree depth varied from 0 (founders) to 4 equivalent discrete generations (t). Four homozygosity parameters (runs of homozygosity, FROH; heterozygosity-rich regions, FHRR; Li and Horvitz's, FLH; and Yang and colleague's FYAN) were computed for each individual, adjusted for the variability in the base population (BP; six individuals) and further jackknifed over autosomes. Individual increases in homozygosity (depending on t) and increases in pairwise homozygosity (i.e., increase in the parents' mean) were computed for each individual in the pedigree, and effective population size (Ne) was computed for five subpopulations (cohorts). Genealogical parameters (individual inbreeding, individual increase in inbreeding, and Ne) were used for comparisons. RESULTS: The mean F was 0.120 ± 0.074 and the mean BP-adjusted homozygosity ranged from 0.099 ± 0.081 (FLH) to 0.152 ± 0.075 (FYAN). After jackknifing, the mean values were slightly lower. The increase in pairwise homozygosity tended to be twofold higher than the corresponding individual increase in homozygosity values. When compared with genealogical estimates, estimates of Ne obtained using FYAN tended to have low root-mean-squared errors. However, Ne estimates based on increases in pairwise homozygosity using both FROH and FHRR estimates of genomic inbreeding had lower root-mean-squared errors. CONCLUSIONS: Parameters characterizing homozygosity may not accurately depict losses of variability in small populations in which breeding policy prohibits matings between close relatives. After BP adjustment, the performance of FROH and FHRR was highly consistent. Assuming that an increase in homozygosity depends only on pedigree depth can lead to underestimating it in populations with shallow pedigrees. An increase in pairwise homozygosity computed from either FROH or FHRR is a promising approach for characterizing autozygosity.


Asunto(s)
Endogamia , Polimorfismo de Nucleótido Simple , Humanos , Porcinos , Animales , Linaje , Homocigoto , Genoma , Genotipo
5.
J Anim Breed Genet ; 140(5): 549-557, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37150976

RESUMEN

The selection of animals for lower environment sensitivity around the optimum trait value can also provide benefits in productivity and welfare. A divergent selection experiment for birth weight environmental variability in mice was successfully conducted over 17 generations. Animals from low variability selected line (L-line) were more robust by having a higher litter size and survival at weaning in a common breeding environment, than those from high variability line (H-line). The objective of this study was to analyze the differences between those divergently selected lines for embryo and fetal survival and for fertility and prolificacy rate. To study embryo survival and ovulation rate, a total of 98 females (34 H-line and 50 L-line) were studied in four generations of the divergent experiment. To analyze fetal survival and fertility rate, 378 female mice (138 H-line and 240 L-line) in 10 generations or the divergent experiment were studied. Ultrasound scans were performed at day 14 of gestation to establish the number of total fetal and the embryo absorptions. Mortality was addressed as the difference between litter size at birth and the number of fetuses at 14 days of gestation. The number of pregnant females in the first 3 days after mating was used to measure fertility. A linear model was also fitted to analyze embryo mortality, litter size, and the number of embryos at 14 days of gestation. A categorical model was then used to study fertility, including line, generation, and its interaction as effects. Despite the fact that there were no significant differences in the ovulation rate, litter size at birth was significantly higher in the L-line than in the H-line (9.82 vs. 8.36 pups, p < 0.001). Moreover, embryo mortality was significantly lower in the L-line than in the H-line (1.39 vs. 2.87 fetuses, p < 0.001). L-line females were more fertile (53.49% vs. 23.26% for the H-line). According to these results, the line selected for low environmental variance would be preferable for robustness and animal welfare.


Asunto(s)
Fertilidad , Reproducción , Femenino , Embarazo , Animales , Ratones , Peso al Nacer/genética , Fertilidad/genética , Parto , Modelos Lineales
6.
Rev Panam Salud Publica ; 47: e35, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36751676

RESUMEN

Objective: To document the evolution of socioeconomic and geographical inequalities in childhood vaccination in Mexico from 2012 to 2021. Methods: Repeated cross-sectional analysis using three rounds of National Health and Nutrition Surveys (2012, 2018, and 2021). Dichotomous variables were created to identify the proportion of children who received no dose of each vaccine included in the national immunization schedule (BCG; diphtheria, pertussis, and tetanus-containing; rotavirus; pneumococcal conjugate; and measles, mumps, and rubella [MMR]), and the proportion completely unvaccinated. The distribution of unvaccinated children was analyzed by state, and by socioeconomic status using the concentration index. Results: The prevalence of completely unvaccinated children in Mexico was low, with 0.3% children in 2012 and 0.8% children in 2021 receiving no vaccines (p = 0.070). Notwithstanding, for each vaccine, an important proportion of children missed receiving any dose. Notably, the prevalence of MMR unvaccinated children was 10.2% (95% CI 9.2-11.1) in 2012, 22.3% (95% CI 20.9-23.8) in 2018, and 29.1% (95% CI 26.3-31.8) in 2021 (p < 0.001 for the difference between 2012 and 2021). The concentration index indicated pro-rich inequalities in non-vaccination for 2 of 5 vaccines in 2012, 3 of 5 vaccines in 2018, and 4 of 5 vaccines in 2021. There were marked subnational variations. The percentage of MMR unvaccinated children ranged from 3.3% to 17.9% in 2012, 5.5% to 36.5% in 2018, and 13.1% to 72.5% in 2021 across the 32 states of Mexico. Conclusions: Equitable access to basic childhood vaccines in Mexico has deteriorated over the past decade. Vigilant equity monitoring coupled with tailored strategies to reach those left out is urgently required.

7.
Rev Panam Salud Publica ; 47: e112, 2023.
Artículo en Español | MEDLINE | ID: mdl-37534054

RESUMEN

Objective: To document trends in inequity in homicide rates in Mexico for the period 2000-2021, at the state and national levels. Methods: An observational, longitudinal ecological study was conducted in which standardized homicide mortality rates were estimated, by municipality and sex. Municipalities were classified in five groups, according to the Social Lag Index. The absolute inequality gap was obtained, as well as differences between groups with very high and very low social lag, for each year of the study period. Results: In the 32 states, an increase was observed in the rate of death by homicide, with higher rates among men but a greater relative increase among women (+127.86% vs. +110.03%). The absolute gap between municipalities with very high and very low social lag narrowed in the period, due to higher homicide rates in municipalities with low social lag and a modest reduction in municipalities with very high social lag. Conclusions: In Mexico, between 2000 and 2021, the absolute gap in deaths by homicide between municipalities with very high and very low social lag declined due to higher homicide rates in municipalities with lower social lag. It is necessary to strengthen policies and actions aimed at addressing the social determinants of interpersonal violence.


Objetivo: Documentar as tendências de desigualdade nas taxas de homicídio do México no período de 2000 a 2021 em nível estadual e nacional. Métodos: Foi realizado um estudo ecológico observacional e longitudinal no qual se estimaram taxas padronizadas de mortalidade por homicídio por município e sexo. Os municípios foram classificados em cinco grupos conforme o índice de defasagem social. Calculou-se a diferença absoluta de desigualdade como a diferença entre os grupos com defasagem social muito alta e muito baixa, para cada ano do período estudado. Resultados: Em todos os 32 municípios, observou-se aumento na taxa de mortalidade por homicídio; as taxas foram mais altas entre homens, embora o aumento relativo tenha sido maior entre as mulheres (variação percentual: 127,86% comparado a 110,03%). A diferença absoluta entre municípios com defasagem social muito alta e muito baixa diminuiu no período estudado devido ao aumento na taxa de mortalidade por homicídio nos municípios com defasagem social baixa e uma certa redução nos que tinham defasagem social muito alta. Conclusões: No México, entre 2000 e 2021, a diferença absoluta nas mortes por homicídio entre municípios com defasagem social muito alta e muito baixa diminuiu devido ao aumento na taxa de homicídios nos municípios com uma menor defasagem social. É necessário reforçar políticas e iniciativas que abordam os determinantes sociais da violência interpessoal.

8.
J Anim Breed Genet ; 139(1): 13-25, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34494688

RESUMEN

In genetic evaluation of horses, the genetic trend does not correspond into a phenotypic trend when using ranking as a phenotype due to its uniform distribution, and some other effects might be absorbing that trend. From a founder population, a further four discrete generations of 100 individuals were simulated under random mating. Then, ten additional discrete generations were simulated by selecting the best 10% of the animals. Likewise, an underlying variable with heritability 0.1 or 0.2, affected by an event environmental influence, generation and permanent environment, was simulated to establish the ranking assignment of 10 random participants or according to the competitive level for each event, in 10 or 100 structured or unstructured events. The ranking trait genetic evaluation model was tested to include or exclude the event effect and the permanent environment effect, depending on the scenario. The results showed that the event effect fitted the different competitive level of each event, leading to a 5% to 23% of selection response improvement for structured competitions. Therefore, the event effect should be included in the genetic evaluation models of horses. The permanent environment fitted or simulated did not significantly improve the selection response. The event effect explained the competition genetic level, by compensating the genetic trend obtained by selection.


Asunto(s)
Modelos Genéticos , Reproducción , Animales , Caballos/genética , Fenotipo
9.
J Anim Breed Genet ; 139(4): 370-379, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35305049

RESUMEN

Uniformity, understood as a similar performance in relevant livestock traits, such as birth weight within the litter, is being included as one of the selection objectives in breeding programmes, especially for polytocous livestock species. A divergent selection experiment for birth weight within-litter variability in mice during 23 generations showed that homogeneous animals were better for litter size, survival and feed efficiency but less heavy than heterogeneous animals. The aim of this study was to compare the reproductive longevity in both divergent lines as time to the end of the reproductive period. Two generations from both lines with an initial number of 43 females and 43 males were mated one to one and stayed together to have consecutive parturitions until the end of the reproductive life. Females were discarded when the time elapsed from the last parturition was longer than 63 days. The time to the end of the reproductive period between both lines was compared by fitting a Cox proportional hazard regression model adjusting for line, generation and its interaction. The rate of parturitions in both lines was also compared using a Prentice-Williams-Peterson model adjusted for the same effects. The low variability line was associated with a higher parturition rate, e.g., adjusted hazard ratio was 2.93 (95% CI 2.17-3.94). The Cox model showed that the low variability females also presented benefits of time to the end of the reproductive period, with an adjusted hazard ratio of 0.26 (95% CI 0.16-0.41). The median of reproductive days was 55.50 in the high variability line whilst the median was 252.50 days for the low variability females. The homogeneous line presented important reproductive advantages suggesting higher robustness and animal welfare. Further research should confirm whether the findings presented here of a better performance in the low variability line could be properly applied to some livestock species.


Asunto(s)
Longevidad , Reproducción , Animales , Peso al Nacer , Femenino , Tamaño de la Camada , Ganado , Masculino , Ratones , Parto , Embarazo , Selección Genética
10.
Genet Sel Evol ; 53(1): 26, 2021 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-33711925

RESUMEN

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.


Asunto(s)
Peso Corporal , Variación Genética , Penaeidae/genética , Animales , Interacción Gen-Ambiente , Penaeidae/crecimiento & desarrollo , Carácter Cuantitativo Heredable
11.
J Anim Breed Genet ; 138(4): 482-490, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33527529

RESUMEN

Measurements from 13 different morphological traits of importance in the Pura Raza Español (PRE) horse were used to estimate genetic and environmental parameters following a heteroscedastic model in which data were assigned to stallions. Data sets used ranged from 20,610 (height at withers) to 48,486 measurements (length of shoulder), and the number of animals analysed in the pedigrees varied from 17,662 (height at withers) to 23,962 (dorsal-sternal diameter). Results of heritabilities of the traits varied from 0.09 (width of chest and upper neck line) to 0.30 (muscular development). Further, genetic correlations between traits and their environmental variability were estimated, obtaining values from -0.56 (muscular development) to 0.69 (height at withers). Also, predicted breeding values for the mean and for the environmental variability were obtained for all horses in the pedigrees, providing individual information about not only the expected phenotypic value of their offspring but also the expected heterogeneity among them. Results proved the possibility of improving morphological traits and reducing the heterogeneity of offspring at a time by the selection of animals and levels of systematic effects.


Asunto(s)
Caballos/genética , Animales , Masculino , Linaje , Fenotipo
12.
Rev Panam Salud Publica ; 45: e47, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34054931

RESUMEN

OBJECTIVE: To appraise the presence and magnitude of inter- and intra-country health inequalities related to HIV in Latin America and the Caribbean (LAC) among young females. METHODS: We analyzed household surveys in twenty LAC countries, that included data from female adolescents and young women (ages 15-24) between 2008 and 2018, measuring inequality with the concentration index of 4 indicators: 1) whether individuals have heard of HIV or not, 2) a composite variable of correct knowledge, 3) reported condom use with the last partner, and 4) whether individuals were ever tested for HIV. RESULTS: Participants from households in countries with higher socioeconomic status are more likely to have heard of HIV, have correct knowledge of HIV transmission, and have used condoms during their last sexual intercourse. The inter-country concentration index for those indicators were 0.352, 0.302 and 0.110, respectively. CONCLUSIONS: Economically disadvantaged female adolescents and young women in LAC face an increased risk for HIV, as they are less aware of HIV and its actual transmission mechanism and are less likely to use condoms with their sexual partners. There is an urgent need to tailor prevention strategies of sexually transmitted infections and HIV for adolescents and young women that are sensitive to their socioeconomic context.

13.
Exp Dermatol ; 29(3): 259-264, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31997403

RESUMEN

Alopecia areata (AA) is an autoimmune disease of the hair follicle. Keratinocytes of the hair follicle generate an immunosuppressive environment by the local secretion of hormones of the hypothalamic-pituitary-adrenal axis of the skin (skin HPA analog). Our objective was to measure the local production of corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), and α-melanocyte-stimulating hormone (α-MSH) in the scalp tissue of patients with AA before and after ultraviolet A1 (UVA-1) phototherapy to determine their role in the pathogenesis of AA and the effect of UVA-1 on the AA hormonal environment. This was a retrospective and descriptive study of skin samples from 22 patients with AA before and after UVA-1 treatment. We compared the changes in the local hormonal environment by measuring CRH, ACTH, type 2 melanocortin receptor (ACTH receptor) and α-MSH with immunohistochemical stains. The positivity of MSH was significantly higher (P = .037) in the post-treatment samples compared with the baseline value. ACTH was significantly higher in intensity (P = .032) in the post-treatment samples compared with the initial value. CRH was significantly higher in intensity (P = .013) in baseline samples compared with the final biopsies. The positivity of the ACTH receptor MC2R was not different between the two groups (P = .626). In AA, an interruption in the signalling of CRH could decrease the local concentration of ACTH and MSH, and consequently, the immunosuppressive effect of these hormones. This phenomenon is normalized in the skin treated with UVA-1. A defective signalling system in the cutaneous HPA axis may be involved in the pathogenesis of AA.


Asunto(s)
Alopecia Areata/radioterapia , Hormonas/metabolismo , Fototerapia/métodos , Cuero Cabelludo/metabolismo , Rayos Ultravioleta , alfa-MSH/metabolismo , Hormona Adrenocorticotrópica/metabolismo , Adulto , Alopecia Areata/metabolismo , Biopsia , Hormona Liberadora de Corticotropina/metabolismo , Folículo Piloso/metabolismo , Humanos , Sistema Hipotálamo-Hipofisario/patología , Inmunohistoquímica , Persona de Mediana Edad , Sistema Hipófiso-Suprarrenal/metabolismo , Receptor de Melanocortina Tipo 2/metabolismo , Estudios Retrospectivos , Transducción de Señal , Piel/metabolismo
14.
Genet Sel Evol ; 52(1): 20, 2020 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-32276582

RESUMEN

BACKGROUND: Control of the environmental variability by genetic selection offers possibilities for new selection objectives for productive traits. This methodology aims at reducing heterogeneity in productive traits and has been applied to several traits and species for which animal homogeneity is profitable. In horse breeding programmes, rank in competitions is a common selection objective but has been challenging to model. In this study, the parameters of environmental variability for the rank of a horse were computed to analyse the capability of a horse to maintain the best ranking across competitions that consist of long-distance races in which the adapted physical condition of the horse is essential. The genetic component of the environmental variance for the rank in endurance competitions was evaluated, which resulted in proposing a new transformation of horse scores in competitions. RESULTS: Homogeneous and heterogeneous variance models were compared by assaying three random effects that affect both the rank and its variability, using endurance ride data consisting of 2863 records. The pedigree relationship matrix contained 5931 animals. The rank trait was transformed into a normalized variable to prevent false estimates of the genetic correlation by inappropriate artificial skewness. The models included the number of participants in the race, sex, and age as systematic effects. The rider, the rider-horse interaction, or an environmental permanent effect were tested as random effects, in addition to additive genetic and residual effects. The models were analysed using the GSEVM program. Estimates of heritability for rank ranged from 0.12 to 0.15. The heterogeneous variance model that fitted the rider was assessed as the best model based on the deviance information criterion. Estimates of genetic variance for rank variability ranged from 0.12 to 0.13. The genetic correlation between the rank and its environmental variability was low and did not differ from 0. CONCLUSIONS: These results offer an opportunity to select animals for canalization by reducing the variability of race results and achieving the best positions, which could be a new selection objective by weighting estimated breeding values for rank and its variability in a selection index.


Asunto(s)
Cruzamiento , Variación Genética , Caballos/genética , Modelos Genéticos , Resistencia Física , Animales , Femenino , Masculino , Linaje , Fenotipo
15.
Cult Health Sex ; 22(10): 1145-1160, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-31682779

RESUMEN

Migrants in transit through Mexico to the USA are at risk of violence, including sexual violence, during the immigration process. This study sought to identify the socio-demographic factors, migration experiences and health conditions associated with the likelihood of sexual violence. A mixed methods study was conducted between 2012 and 2015. The quantitative phase of the work involved a non-random sample (n = 3539) of migrants who were the users of migrant shelters in Mexico. A probit regression model was used to identify the variables associated with the experience of sexual violence by participants. A total of 58 semi-structured interviews took place with migrants who had either experienced sexual violence or who were acquainted with the sexual violence experienced by other migrants. Of those who experienced any kind of violence, 5.7% reported having experienced sexual violence, with statistically significant differences by gender. According to male migrants, women in transit had the advantage of having an 'entry ticket [to the USA] between their legs'. The dynamics of undocumented transit migration provide multiple opportunities for gender-based inequality and sexual violence. We consider the major underreporting of sexual violence due to the stigma and normalisation of violence, in a social context marked by impunity.


Asunto(s)
Violación/estadística & datos numéricos , Delitos Sexuales/estadística & datos numéricos , Migrantes/estadística & datos numéricos , Adulto , América Central/etnología , Emigración e Inmigración , Femenino , Humanos , Entrevistas como Asunto , Masculino , México/etnología , Minorías Sexuales y de Género/estadística & datos numéricos , Estados Unidos
16.
Reprod Domest Anim ; 55(7): 814-821, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32320085

RESUMEN

The low fertility and offspring survival indicators in alpacas can be partially due to their particularity seasonal reproduction that reduces the opportunities of the females to become pregnant within a season, with the survival of the offspring concerned by the availability of food and exposure to diseases that depends on the calving date. Optimizing the date of delivery and reducing its variability are shown as eligible criteria that could be used as selection criteria within the genetic improvement programmes in alpacas, the calving date being a much more appropriate trait to measure and optimize fertility unlike of age at first calving and the calving interval, this due to the reproductive seasonality in camelids. For this study, 6,533 birth date records were taken between 2001 and 2018 of Peruvian alpacas, to estimate the genetic parameters. Models assuming heterogeneity in the residuals were fitted besides classical homogeneous models to address, not only the possibility of forwarding or delaying the calving date, but also the trend to have parturitions in similar dates. The heritability and repeatability ranged from 0.07 to 0.20 for a homogeneity model and from 0.08 to 0.23 for a heterogeneity model, and suggest the possibility of advancing or delaying the calving date. It should be taken into account that the gestation length of camelids makes it difficult to adapt many reproductive traits, and trying to centre the calving date could delay it. It was concluded the feasibility to genetically select the calving date, also in the production of camels and dromedaries, which have the same reproductive characteristics as alpacas. This selection can be combined with other traits. The heterogeneity model was shown to provide a better fit.


Asunto(s)
Camélidos del Nuevo Mundo/fisiología , Parto/fisiología , Animales , Cruzamiento , Camélidos del Nuevo Mundo/genética , Femenino , Parto/genética , Perú , Embarazo , Reproducción/genética , Reproducción/fisiología , Estaciones del Año
17.
Salud Publica Mex ; 62(5): 511-520, 2020.
Artículo en Español | MEDLINE | ID: mdl-32697902

RESUMEN

OBJECTIVE: To measure health inequality in the use of screen-ing services in adults from 20 to 59 years of age from the 2006 and 2012 national health and nutrition surveys. MATERIALS AND METHODS: dults (detection of diabetes, hypertension, breast cancer, cervical cancer and prostate cancer), the Kuznets index, the slope inequality index and the health concentration index were estimated. Considering as social indicators schooling, ethnicity, unemployment, socioeconomic level and type of health protection. RESULTS: The coverage of the five tests increased, but the inequality observed only decreased in the interventions in women; and in the case of the detection of prostate cancer it was increased. CONCLUSIONS: While it is important to monitor the performance of curative services, the challenge remains to ensure effective and equitable access to early diagnosis services.


OBJETIVO: Medir la desigualdad en el uso de servicios de tamizaje en adultos de 20 a 59 años, a partir de las encuestas nacionales de salud y nutrición 2006 y 2012. MATERIAL Y MÉTODOS: A partir de la selección de cinco indicadores de tamizaje en adultos (detección de diabetes, hipertensión y cánceres de mama, cérvicouterino y de próstata) se estimaron el índice de Kuznets, el índice de desigualdad de la pendiente y el índice de concentración de salud, considerando como indicadores sociales la escolaridad, etnicidad, desempleo, nivel socioeconómico y tipo de protección en salud. RESULTADOS: Las coberturas de las cinco pruebas se incrementaron, sin embargo, la desigualdad observada disminuyó únicamente en las intervenciones en mujeres; en el caso de la detección de cáncer de próstata se incrementó. CONCLUSIONES: Si bien es importante monitorear el desempeño de los servicios curativos, persiste el reto de asegurar el acceso efectivo y equitativo a servicios de diagnóstico temprano.


Asunto(s)
Pruebas Diagnósticas de Rutina/estadística & datos numéricos , Disparidades en el Estado de Salud , Disparidades en Atención de Salud , Factores Socioeconómicos , Adulto , Detección Precoz del Cáncer/estadística & datos numéricos , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , México/epidemiología , Persona de Mediana Edad , Adulto Joven
18.
Int J Equity Health ; 18(1): 49, 2019 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-31154998

RESUMEN

BACKGROUND: Adequate access to sexual and reproductive health services is associated with better results. Analyzing the differences in access and outcomes of sexual and reproductive health (SRH) by share of poverty at the regional level makes it possible to measure the magnitude of the challenge of inequity. This paper aims to estimate the magnitude of health inequality in SRH in Ecuador for the period 2009-2015. METHODS: This study analyzed health inequalities in sexual and reproductive health indicators (obstetric and abortion complications, caesarean and home deliveries, adolescent fertility, and maternal mortality) for 2009 and 2015 comparing provinces in Ecuador. The absolute and relative gaps were estimated between provinces grouped by the percentage of individuals in multidimensional poverty; the slope index of inequality and the relative index of inequality were estimated as measures of gradient; and finally, the concentration index was also estimated. RESULTS: The analysis identified that obstetric complications, abortion complications, and cesareans have tended to increase from 2009 to 2015, without relevant differences between provinces ordered by poverty. Adolescent fertility decreased in the country as well as the inequality in its distribution among provinces: the CI was - 0.046 in 2015, down from - 0.084 in 2009. Home deliveries as a ratio of total deliveries have a decreasing trend with mixed results in terms of inequality: while there is a decrease in the absolute gap from - 211.06 to 184.4 between 2009 and 2015, the concentration index increased from - 0.331 to - 0.496. Finally, the maternal mortality rate increased in the period, also with greater inequality: from an absolute gap of - 39.30 in 2019, up to - 46.7 in 2015. In the same direction, the CI went from - 0.127 to - 0.174. CONCLUSIONS: Ecuador faces major challenges in terms of both levels and inequalities in SRH outcomes and access to services. These inequalities related to poverty highlight the persistence of social inequities in the country. These health inequalities affect the wellbeing of Ecuadorian women but they are amendable. There is a need for pro-equity interventions, with stronger efforts in areas (provinces) with larger socioeconomic vulnerabilities.


Asunto(s)
Disparidades en el Estado de Salud , Pobreza/estadística & datos numéricos , Salud Reproductiva/estadística & datos numéricos , Salud Sexual/estadística & datos numéricos , Adolescente , Adulto , Ecuador , Femenino , Humanos , Masculino , Persona de Mediana Edad , Embarazo , Adulto Joven
19.
Genet Sel Evol ; 51(1): 27, 2019 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-31195962

RESUMEN

BACKGROUND: Selection of mice for decreased environmental variability of birth weight has achieved higher survivability and larger litter size as a correlated response to canalized selection, which suggests higher welfare and robustness, and animals that are more homogeneous. However, in these studies, animals were not exposed to an environmental challenge. To demonstrate the advantages of this mouse line with a low environmental variability of birth weight, animals from two divergent lines (high and low variability of birth weight) were subjected to feed restriction. The objective of this study was to use these divergent lines to compare their response in terms of robustness against an environmental challenge. At weaning, 120 females, i.e. four full-sib females from 10 random litters of three consecutive generations of selection, were chosen from these divergent lines. The total number of females was divided into four groups, which were subjected to a feeding regimen by imposing different levels of feed restriction (i.e. 75, 90 and 85% of full ad libitum feed across three generations, respectively) in different combinations during the growth and reproduction periods. RESULTS: Animals from the "low" line were less sensitive to a change in feed level than those from the "high" line. Regarding reproduction, the "low" line performed better in terms of number of females having parturitions, number of parturitions, and litter size. Imposing a feed restriction on female mice during their growth period did not affect the birth weight of their pups. The "low" line was preferred because of its higher reproductive efficiency and survival under an environmental challenge. CONCLUSIONS: Selection for decreased environmental variability of birth weight produces animals that are less sensitive to environmental conditions, which can be interpreted as having greater robustness.


Asunto(s)
Variación Biológica Poblacional , Peso al Nacer , Restricción Calórica , Selección Genética , Animales , Ambiente , Femenino , Especiación Genética , Masculino , Ratones , Selección Artificial
20.
Environ Res ; 176: 108554, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31288198

RESUMEN

BACKGROUND: Organophosphate (OP) pesticides can be hazardous to human health if not applied with appropriate precautions. There is evidence in the Maule region of Chile that rural schoolchildren are exposed to OP pesticides. OBJECTIVE: To evaluate the effectiveness of an educational intervention on OP exposure and understanding of pesticides and their hazards (risk perception) in two school communities in the Maule Region of Chile during 2016. METHOD: We conducted a quasi-experimental study about the effects on OP pesticide exposure of a community outreach and education program (COEP) administered in four 2-h sessions that's included hands-on activities among 48 schoolchildren from two rural schools. The intervention was directed to groups of parents and school-children separately, and aimed to educate them about the risks of exposure to pesticides and their effects on health. We measured 3,5,6-trichloro-2-pyridinol (TCPy), 2-isopropyl-4-methyl-6-hydroxypyrimidine (IMPY), malathion dicarboxylic acid (MDA), p-nitrophenol (PNP), specific urinary metabolites of the OP pesticides chlorpyrifos, diazinon, malathion and parathion, respectively, as well as the non-specific diethylakylphosphates (DEAPs) and dimethylalkylphosphates (DMAPs) in 192 urine samples of schoolchildren collected before and after the intervention. The risk perception of school children and their parents was also assessed through a questionnaire before and after the intervention. Generalized Estimated Equations were used to account for each child's repeated measures during four sessions, two in September 2016 (pre-intervention) and two in November 2016 (post-intervention). RESULTS: The intervention level had significant effect on the risk perception of adults and children, which increased after the intervention. However, the intervention was not associated with reduced of urinary metabolites levels, with no significant differences between the pre and post measures. The detection frequencies were 1.1% (MDA), 71.4% (TCPy), 43.3% (IMPY), 98.96% (PNP), and 100% (DEAPs and DMAPs). Higher DEAPs urine concentrations were associated with eating more fruit at school (p = 0.03), a younger age (p = 0.03), and being male (p = 0.01). DMAPs showed no associations with potential predictor variables (e.g. OPs applied at home, fruit consumption at school, among others). Higher TCPy was associated with attending a school closer to farms (p = 0.04) and living in a home closer to farm fields (p = 0.01); higher PNP was marginally associated with children younger age (p = 0.035). CONCLUSION: Environmental exposure to OP pesticides was unchanged even after behavior changes. It is possible that a longer time period is needed to observe changes in both behavior and urinary metabolites. The levels of DEP and DMP metabolites found here are above the reference population of the US, and our findings indicate exposure to a wide variety of OP pesticides. Given that individual-level interventions were not associated with lower exposures, efforts to reduce exposure must occur upstream and require stricter regulation and control of pesticide use by government agencies.


Asunto(s)
Cloropirifos , Exposición a Riesgos Ambientales/estadística & datos numéricos , Compuestos Organofosforados/orina , Plaguicidas/orina , Adulto , Agricultura , Niño , Chile , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Insecticidas , Masculino
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