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1.
Poult Sci ; 103(10): 104022, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39068694

RESUMO

The maternal diet and egg incubation temperature are some of the factors that can influence the embryonic development and performance of the newly chicks at 15 d of age. This study evaluated the effects of adding a blend of organic acids, essential oils, curcumin, tannins, vitamin E, and zinc microencapsulated in to the diet of female quails (Coturnix coturnix japonica) on their productive, reproductive performance and redox parameters of their eggs and the interaction of maternal diet × incubation temperature on embryo (E16 and E18) and chicks development. At 98 d of age, 64 female quails with a mean body weight of 150 g ± 0.5 were distributed into two treatments: a Basal diet or a diet supplemented with blend (Sannimix). The eggs from each female were incubated at 37.5°C (Control) and 38.5°C (High Temperature) throughout the incubation period. After hatching, chicks were distributed in a 2 (maternal diet) × 2 (incubation temperature) factorial design. Female quails supplemented with Sannimix showed better productive and reproductive performance and produced higher-quality embryos. Their offspring had greater weight at hatch and at 15 d of age. The eggs and offspring of supplemented with Sannimix female quails showed better oxidative stability. At E16 and E18, High Temperature increased yolk sac utilization and gene expression of the growth hormone receptor (GHR). At E16, embryos from supplemented with Sannimix female quail had higher expression of insulin-like growth factor type I (IGFI) and heat shock protein 70 kDa genes. At 15 d of age, highest expression of the GHR and IGFI genes was observed in chicks from female quails fed the Sannimix diet, regardless of incubation temperature. Regarding the maternal diet × incubation temperature an improved result was observed for chicks from female quails fed with Sannimix even when eggs are exposed to High Temperature during the incubation. The supplementation of quail diets with blend Sannimix improves productive and reproductive performance, egg quality and their embryos, as well as their offspring quality.


Assuntos
Ração Animal , Coturnix , Curcumina , Dieta , Suplementos Nutricionais , Óleos Voláteis , Vitamina E , Zinco , Animais , Ração Animal/análise , Dieta/veterinária , Feminino , Suplementos Nutricionais/análise , Coturnix/crescimento & desenvolvimento , Óleos Voláteis/administração & dosagem , Vitamina E/administração & dosagem , Zinco/administração & dosagem , Zinco/metabolismo , Curcumina/administração & dosagem , Curcumina/farmacologia , Taninos/administração & dosagem , Temperatura , Reprodução/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos
2.
Anim Reprod ; 21(1): e20230146, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38562607

RESUMO

The subcortical maternal complex, which consists of maternal-effect genes, plays a crucial role in the development of oocytes and preimplantation embryo until the activation of the zygote genome. One such gene, known as peptidyl-arginine deiminase VI (Padi6), is involved in the oocyte maturation, fertilization and embryonic development. However, the precise function of Padi6 gene in buffalo is still unclear and requires further investigation. In this study, the sequence, mRNA and protein expression patterns of Padi6 gene were analyzed in oocytes, preimplantation embryos and somatic tissues of buffalo. The coding sequence of gene was successfully cloned and characterized. Real-time quantitative PCR results indicated an absence of Padi6 transcripts in somatic tissues. Notably, the expression levels of Padi6 in oocytes showed an increased from the germinal vesicle stage to metaphase II stage, followed by a rapid decrease during the morula and blastocyst stages. Immunofluorescence analysis confirmed these findings, revealing a noticeable decline in protein expression levels. Our research provides the initial comprehensive expression profile of Padi6 in buffalo oocytes and preimplantation embryos, serving as a solid foundation for further investigations into the functionality of maternal-effect genes in buffalo.

3.
J Exp Zool A Ecol Integr Physiol ; 341(5): 563-577, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38470019

RESUMO

Future climate change scenarios project that the increase in surface temperatures will affect ocean temperatures, inducing shifts in marine biodiversity. Sea turtles are species that are particularly vulnerable to the effects of climate change because temperature is a factor that influences embryonic development. We collected clutches of olive ridley turtles from a mass-nesting beach in the Mexican Pacific, which were incubated in ex situ conditions. When the hatchlings emerged, we measured the body condition index-which evaluates the weight-length relationship-and swim thrust, both were considered traits associated with fitness, termed "fitness proxies," and evaluated the effects of incubation temperature, maternal effects, and paternity on these fitness proxies. The body condition index was correlated positively and significantly with the arribada month and temperature during the last third of the incubation period but showed an inverse relationship with the maternal effect. While swim thrust was positively correlated with the maternal effect and the arribada month, there was an inverse relationship with incubation temperature during the first third of the period. Paternity, whether single or multiple, did not have a significant effect on either fitness proxies; however, it may have effects on the average fitness of a population of hatchlings. These results underscore the need to expand research on the sublethal effects of high incubation temperatures on the adaptation and survival of sea turtles, particularly in scenarios of rapid climate change.


Assuntos
Temperatura , Tartarugas , Animais , Tartarugas/fisiologia , Feminino , México , Masculino , Mudança Climática , Oceano Pacífico , Comportamento de Nidação/fisiologia
4.
Trop Anim Health Prod ; 55(5): 330, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37749453

RESUMO

Our objective was to evaluate the productive parameters of ewes and their lambs in relation to ewe age and to develop models for predicting lamb weight at birth and weaning in a tropical warm-climate pasture. Individual data were collected from 273 ewes and 273 lambs, between 2013 and 2021. During this period all animals were kept on pastures of Brachiaria brizantha cv. Marandu All lambs in the experiments were supplemented in creep-feeding. A descriptive statistical analysis was performed using the PROC SUMMARY procedure in SAS (SAS University Edition, SAS Institute Inc. Cary, CA, USA). Pearson correlation coefficients between variables were estimated using the PROC CORR procedure in SAS (SAS University Edition, SAS Institute Inc. Cary, CA, USA). Model adjustments and variable selection were performed using PROC REG in SAS (SAS University Edition, SAS Institute Inc. Cary, CA, USA). The STEPWISE option and Mallow's C(p) were used to select the variables included in the equations. Outliers were identified by evaluating the studentized residuals based on the predicted values from the equations. Residual analysis was predicted by regression minus observed values and those that fell outside the range of -2.5 to 2.5 were removed. Several statistics were used to assess the predictability of the equations, including the coefficients of determination (r2) and mean standard error (RMSE). The average ewe age at lambing was 3.4 ± 1.7 years, with an average weight of 56.9 ± 8,9 kg and average body condition score (BCS) of 2,4 ± 0.8 points. The average ewe age at weaning was 51.1 ± 7.9, with average BCS of 1.8 ± 0.8 points. The average lamb at birthing was 3.9 ± 0.9 kg. The average lamb at weaning was 21.0 ± 4.9, with daily gain of 0.2 ± 0.1 kg/day and total gain of 17.1 ± 4.7 kg birth to weaning. The lamb produced by ewe at lambing was 5.3 ± 1.7 kg/ewe. The lamb weaned by ewe at weaning was 28.7 ± 10.8 kg/ewe. The ratios of lamb produced per ewe at birth and at weaning were 0.1 ± 0.03 and 0.6 ± 0.2, respectively. The lamb's birth weight showed a positive linear relationship with the age of the ewe, increasing by 115 g per year of age. The regression equations adjusted for ewe age had maximum points ranging from 4.2 to 5.2, occurring at average age of 4,7 years. The other characteristics showed a quadratic tendency. The results suggest the culling of ewes at five years of age to generate lambs with ideal weight at birth and at weaning raised in warm tropical pastures.


Assuntos
Brachiaria , Carneiro Doméstico , Humanos , Ovinos , Animais , Feminino , Peso ao Nascer , Desmame , Modelos Teóricos
5.
Immunobiology ; 228(3): 152395, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37210753

RESUMO

BACKGROUND: Allergies are increasing worldwide. The presence of atopic diseases in the mother propagates the onset of allergic diseases in the offspring with a considerably stronger penetrance than atopic diseases of the father. Such observation challenges genetic predispositions as the sole cause of allergic diseases. Epidemiological studies suggest that caregiver stress in the perinatal period may predispose offspring to asthma. Only one group has studied the link between prenatal stress and neonatal asthma susceptibility in a murine model. OBJECTIVES: We aimed to study if the neonatal increased risk of developing allergic lung inflammation persists after puberty and if there are sex differences in susceptibility. METHODS: Pregnant BALB/c mice were subjected to a single restraint stress exposure at day 15 of gestation. Pups were separated by gender and subjected to a well-known sub-optimal asthma model after puberty. RESULTS: Adult mice born to stressed dams were more susceptible to developing allergic pulmonary inflammation since an increase in the number of eosinophils in bronchoalveolar lavage (BAL), a greater peribronchial and perivascular infiltrate, a higher proportion of mucus-producing cells, and increased IL-4 and IL-5 levels in BAL were detected compared to control mice. These effects were more profound in females than males. Moreover, only females from stressed dams showed an increase in IgE levels. CONCLUSIONS: Increased litter susceptibility to develop allergic lung inflammation induced by maternal stress persists after puberty and is more potent in females than in male mice.


Assuntos
Asma , Hipersensibilidade , Pneumonia , Gravidez , Masculino , Feminino , Animais , Camundongos , Asma/etiologia , Eosinófilos , Lavagem Broncoalveolar/efeitos adversos , Pneumonia/complicações , Camundongos Endogâmicos BALB C , Pulmão , Modelos Animais de Doenças , Ovalbumina , Líquido da Lavagem Broncoalveolar
6.
Plant Cell Environ ; 44(8): 2716-2728, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33721328

RESUMO

Ground-level ozone is a global air pollutant with high toxicity and represents a threat to plants and microorganisms. Although beneficial microorganisms can improve host performance, their role in connecting environmentally induced maternal plant phenotypes to progeny (transgenerational effects [TGE]) is unknown. We evaluated fungal endophyte-mediated consequences of maternal plant exposure to ozone on performance of the progeny under contrasting scenarios of the same factor (high and low) at two stages: seedling and young plant. With no variation in biomass, maternal ozone-induced oxidative damage in the progeny that was lower in endophyte-symbiotic plants. This correlated with an endophyte-mediated higher concentration of proline, a defence compound associated with stress control. Interestingly, ozone-induced TGE was not associated with reductions in plant survival. On the contrary, there was an overall positive effect on seedling survival in the presence of endophytes. The positive effect of maternal ozone increasing young plant survival was irrespective of symbiosis and only expressed under high ozone condition. Our study shows that hereditary microorganisms can modulate the capacity of plants to transgenerationally adjust progeny phenotype to atmospheric change.


Assuntos
Endófitos/fisiologia , Epichloe/fisiologia , Lolium/fisiologia , Ozônio , Biomassa , Lolium/efeitos dos fármacos , Lolium/microbiologia , Ozônio/farmacologia , Plântula/fisiologia , Simbiose
7.
Rev. bras. zootec ; 50: e20180224, 2021. tab
Artigo em Inglês | VETINDEX | ID: biblio-1443210

RESUMO

We aimed to evaluate the effects of sex and the linear and quadratic components of age of dam at calving, as well as apply a mixed model including maternal effect for the genetic evaluation of weaning (WW) and yearling (YW) weights. The phenotypic database was composed by Charolais, Caracu, Aberdeen Angus, and Canchim purebred and crossbred animals. Single-trait analyses were performed using models that included the maternal effect for WW and YW traits, and a model ignoring this effect on YW (YWNM). The Deviance Information Criterion (DIC), model posterior probabilities (MPP), accuracy of breeding values (ACC), and Spearman's rank correlation were applied to compare the models including and ignoring the maternal effect on YW. Sex and age of dam at calving had significant effects on WW and YW. The direct heritability estimates were 0.21±0.03 and 0.05±0.02, and the maternal heritabilities were 0.11±0.02 and 0.02±0.01 for WW and YW, respectively. The heritabilities estimated for YW may have been influenced by the several genetic groups in the population and by used conventional animal model, which may not have been the better fit model to evaluate YW in this population. The DIC, MPP, and ACC values indicated that YW outperformed the YWNM model, but the rank correlation and percentages of individuals selected in common suggested that the best animals would be selected independently of the model chosen.


Assuntos
Animais , Bovinos , Desmame , Pesos e Medidas Corporais/veterinária , Hereditariedade , Seleção Artificial , Perfil Genético
8.
BMC Plant Biol ; 20(1): 188, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32349671

RESUMO

BACKGROUND: The study of cold tolerance in maize seeds and seedlings through physiological quality assessments, as well as the genetic control associated with this trait, allows an early characterization of genotypes. Here we studied the genetic control for cold tolerance during the germination process in maize seeds and genes influenced by this stress. RESULTS: Six maize lines were used, three classified as tolerant and three as susceptible to low germination temperature. A field was developed to produce the hybrid seeds, in a partial diallel scheme including the reciprocal crosses. For the expression analysis, seeds from two contrasting lines were used, as well as their hybrid combination and their reciprocal crosses, on dried and moistened seeds at 10 °C for 4 and 7 days. It was evaluated the catalase (CAT) and esterase (EST) enzymes, heat-resistant proteins and the genes Putative stearoyl-ACP desaturase (SAD), Ascorbate Peroxidase (APX), Superoxide Dismutase (SOD) and Mitogen Activated Protein Kinase (ZmMPK5). The estimated values ​​for heterosis, general and specific combining abilities and reciprocal maternal and non-maternal effects were carried out and it showed that there is heterosis for germination at low temperatures, also the non-additive genes were more important and there was a reciprocal effect. CONCLUSIONS: There is a greater expression of the CAT and EST enzymes in moistened seeds at seven days and there is less expression of heat-resistant proteins and the SAD gene at seven days of moistening. Also, there are variations in the expression of the APX, SOD and ZmMPK5 genes in dried and moistened seeds, as well as among the genotypes studied.


Assuntos
Regulação da Expressão Gênica de Plantas , Germinação/genética , Termotolerância/genética , Zea mays/genética , Água , Zea mays/embriologia , Zea mays/enzimologia
9.
J Exp Bot ; 70(18): 4793-4806, 2019 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-31278409

RESUMO

Emergence at an appropriate time and place is critical for maximizing plant fitness and hence sophisticated mechanisms such as seed dormancy have evolved. Although maternal influence on different aspects of dormancy behavior has been identified, its impact under field conditions and its relation to plant fitness has not been fully determined. This study examined maternal effects in Polygonum aviculare on release of seed primary dormancy, responses to alternating temperatures, induction into secondary dormancy, and field emergence patterns as influenced by changes in the sowing date and photoperiod experienced by the mother plant. Maternal effects were quantified using population threshold models that allowed us to simulate and interpret the experimental results. We found that regulation of dormancy in P. aviculare seeds by the maternal environment is instrumental for maximizing plant fitness in the field. This regulation operates by changing the dormancy level of seeds dispersed at different times (as a consequence of differences in the sowing dates of mother plants) in order to synchronize most emergence to the seasonal period that ultimately guarantees the highest reproductive output of the new generation. Our results also showed that maternal photoperiod, which represents a clear seasonal cue, is involved in this regulation.


Assuntos
Dormência de Plantas , Polygonum/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Aptidão Genética , Germinação , Temperatura
10.
Plant Biol (Stuttg) ; 20(2): 252-262, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29106773

RESUMO

Even though exhaustively studied, dormancy alleviation in diaspores of Urochloa humidicola (Rendle) Morrone & Zuloaga remains a mystery. To clarify this, we asked the following question: could dormancy alleviation in diaspores of this species be associated with ageing, GA/ABA balance and remaining structures of the panicoid spikelet? We answer this question using diaspores of U. humidicola cv. BRS Tupi as a biological model, a cultivar with a wide edaphoclimatic range in Neotropical areas and whose diaspores possess 'deep dormancy' when dispersed. We analysed both germination and early plant development using a split-plot model. Our findings demonstrate that dormancy alleviation in diaspores of U. humidicola is a synergic phenomenon driven by crosstalk between age, GA/ABA balance and remaining structures of the panicoid spikelet covering caryopses, since this interaction acts on the dynamics of germination and early plant development. We demonstrate that: (i) spreading germination time is a maternal survival mechanism of this species, which has repercussions for occupational aggressiveness of the species; (ii) remaining structures of the panicoid spikelet covering caryopses are the main modulator of embryo development. These structures control the after-ripening process, which is modulated by some molecular factor. We also highlight that it is necessary to review concepts about dormancy of dispersal units in this grass species.


Assuntos
Dormência de Plantas/fisiologia , Poaceae/fisiologia , Dispersão de Sementes , Ecologia , Germinação/fisiologia , Poaceae/anatomia & histologia , Sementes/anatomia & histologia , Sementes/fisiologia , Clima Tropical , Água/metabolismo
11.
Acta Sci. Anim. Sci. ; 39(3): 323-328, July.-Sept.2017. tab
Artigo em Inglês | VETINDEX | ID: vti-716828

RESUMO

The data set for estimation of genetic and phenotypic parameters of reproductive traits in Kordi sheep were collected from 1996 to 2013. The reproductive traits included age at first lambing (AFL), number of lambs born (NLB/EL) and weaned (NLW/EL) per ewe in each lambing, total weight of lambs born (TWLB/EL) and weaned (TWLW/EL) per ewe in each lambing, total number of lambs born (TNLB) and weaned (TNLW) per ewe, total weight of lambs born (TWLB) and weaned (TWLW) per ewe. The genetic parameters were estimated through restricted maximum likelihood method using WOMBAT. The effects of environmental factors (year of lambing, type of birth, maternal age at lambing) on all reproductive traits were significant (p 0.01). Direct heritability, maternal heritability and the ratio of maternal permanent environmental variance to phenotypic variance for reproductive traits were estimated in the range from 0.07 to 0.18, 0.03 to 0.08 and 0.01 to 0.03, respectively. Genetic and phenotypic correlations between reproductive traits were estimated to be positive and within the range of 0.09 to 0.96 and 0.02 to 0.29, respectively. The results suggest that selection based on number of lambs born per ewe can be more effective than other traits in improving reproductive performance in Kordi ewes.(AU)


O conjunto de dados para a estimativa de parâmetros genéticos e fenotípicos de características reprodutivas em ovinos Kordi foi coletado de 1996 a 2013. As características reprodutivas incluíram idade ao primeiro parto, número de cordeiros nascidos e desmamados por ovelha em cada parição, peso total de cordeiros nascidos e desmamados por ovelha em cada parição, número total de cordeiros nascidos e desmamados por ovelha, peso total de cordeiros nascidos e desmamados por ovelha. Os parâmetros genéticos foram estimados pelo método de máxima verossimilhança restrita usando WOMBAT. Os efeitos dos fatores ambientais (ano de parto, tipo de nascimento, idade materna de parição) em todas as características reprodutivas foram significativos (p < 0,01). A herdabilidade direta, a herdabilidade materna e a razão entre variância ambiental permanente materna e variância fenotípica para características reprodutivas foram estimadas na faixa de 0,07 a 0,18; de 0,03 a 0,08 e de 0,01 a 0,03, respectivamente. As correlações genéticas e fenotípicas entre as características reprodutivas foram estimadas como sendo positivas e na faixa de 0,09 a 0,96 e de 0,02 a 0,29, respectivamente. Os resultados sugerem que a seleção baseada no número de cordeiros nascidos por ovelha pode ser mais eficaz do que outras características para melhorar o desempenho reprodutivo em ovelhas Kordi.(AU)


Assuntos
Animais , Ovinos/anatomia & histologia , Ovinos/genética , Fenômenos Genéticos , Fenômenos Reprodutivos Fisiológicos/genética , Hereditariedade
12.
Acta sci., Anim. sci ; 39(3): 323-328, July.-Sept.2017. tab
Artigo em Inglês | VETINDEX | ID: biblio-1459728

RESUMO

The data set for estimation of genetic and phenotypic parameters of reproductive traits in Kordi sheep were collected from 1996 to 2013. The reproductive traits included age at first lambing (AFL), number of lambs born (NLB/EL) and weaned (NLW/EL) per ewe in each lambing, total weight of lambs born (TWLB/EL) and weaned (TWLW/EL) per ewe in each lambing, total number of lambs born (TNLB) and weaned (TNLW) per ewe, total weight of lambs born (TWLB) and weaned (TWLW) per ewe. The genetic parameters were estimated through restricted maximum likelihood method using WOMBAT. The effects of environmental factors (year of lambing, type of birth, maternal age at lambing) on all reproductive traits were significant (p 0.01). Direct heritability, maternal heritability and the ratio of maternal permanent environmental variance to phenotypic variance for reproductive traits were estimated in the range from 0.07 to 0.18, 0.03 to 0.08 and 0.01 to 0.03, respectively. Genetic and phenotypic correlations between reproductive traits were estimated to be positive and within the range of 0.09 to 0.96 and 0.02 to 0.29, respectively. The results suggest that selection based on number of lambs born per ewe can be more effective than other traits in improving reproductive performance in Kordi ewes.


O conjunto de dados para a estimativa de parâmetros genéticos e fenotípicos de características reprodutivas em ovinos Kordi foi coletado de 1996 a 2013. As características reprodutivas incluíram idade ao primeiro parto, número de cordeiros nascidos e desmamados por ovelha em cada parição, peso total de cordeiros nascidos e desmamados por ovelha em cada parição, número total de cordeiros nascidos e desmamados por ovelha, peso total de cordeiros nascidos e desmamados por ovelha. Os parâmetros genéticos foram estimados pelo método de máxima verossimilhança restrita usando WOMBAT. Os efeitos dos fatores ambientais (ano de parto, tipo de nascimento, idade materna de parição) em todas as características reprodutivas foram significativos (p < 0,01). A herdabilidade direta, a herdabilidade materna e a razão entre variância ambiental permanente materna e variância fenotípica para características reprodutivas foram estimadas na faixa de 0,07 a 0,18; de 0,03 a 0,08 e de 0,01 a 0,03, respectivamente. As correlações genéticas e fenotípicas entre as características reprodutivas foram estimadas como sendo positivas e na faixa de 0,09 a 0,96 e de 0,02 a 0,29, respectivamente. Os resultados sugerem que a seleção baseada no número de cordeiros nascidos por ovelha pode ser mais eficaz do que outras características para melhorar o desempenho reprodutivo em ovelhas Kordi.


Assuntos
Animais , Fenômenos Genéticos , Ovinos/anatomia & histologia , Ovinos/genética , Fenômenos Reprodutivos Fisiológicos/genética , Hereditariedade
13.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);68(4): 1043-1052, jul.-ago. 2016. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: lil-792477

RESUMO

Compararam-se dois modelos (com ou sem o efeito materno) na estimativa de parâmetros genéticos por meio do fator de Bayes (FB) e do critério de informação da deviance (DIC). Adicionalmente, avaliaram-se as tendências genéticas, maternas e fenotípicas em características de crescimento de bovinos da raça Tabapuã do estado da Bahia. O modelo que incluiu o efeito materno proporcionou menores valores de FB (167629,2; 117341,2 e 124804,8) e DIC (174550,0; 120242,7 e 128037,2) para pesos aos 205 (P205), 365 (P365) e 550 (P550) dias de idade, respectivamente. As estimativas médias, a posteriori, das herdabilidades diretas e maternas foram 0,33; 0,43 e 0,44 e 0,15; 0,14 e 0,16 para as três características, respectivamente. As tendências genéticas para o efeito direto foram de 0,4415 e 0,3613kg/ano para P205 e P365 e representam incrementos de apenas 0,25 e 0,15% nas médias das características ao ano. As tendências genéticas maternas para as três características demonstraram perdas e indicam ausência de seleção de matrizes para boa habilidade materna. Apesar de existir variabilidade genética suficiente para justificar ganhos genéticos via seleção, estes e os ganhos fenotípicos foram pequenos, sugerindo necessidade de melhorias genéticas e ambientais.(AU)


We compared two models (with or without maternal effect) in the estimation of genetic parameters through Bayes Factor (BF) and the Deviance Information Criterion (DIC). Additionally, we evaluated the genetic, maternal and phenotypic trends in Tabapuã bovine growth characteristics in the state of Bahia. The model that included the maternal effect provided smaller BF values (167,629.2; 117,341.2 and 124,804.8) and DIC (174,550.0; 120,242.7 and 128,037.2) for weights at 205 (W205), 365 (W365) and 550 (W550) days of age, respectively. The average estimates, a posteriori, the direct and maternal heritability (0.33, 0.43 and 0.44) and (0.15, 0.14 and 0.16) for the three characteristics, respectively. Genetic trends for direct effect were 0.4415 and 0.3613kg/year for W205 and W365 and presented increases of 0.25 and 0.15% in the average characteristics of the year. The phenotypic trend for W205 was 0.7039kg/year. Maternal genetic trends for the three characteristics showed losses and indicate absence of selection matrices for good maternal ability. Despite the magnitude of the estimated direct and maternal heritability, they indicate genetic gain opportunities, genetic and phenotypic trends indicated few direct gains and no gains for maternal ability.(AU)


Assuntos
Animais , Bovinos , Fenômenos Genéticos , Hereditariedade/genética , Fenótipo , Teorema de Bayes
14.
Arq. bras. med. vet. zootec. (Online) ; 68(4): 1043-1052, jul.-ago 2016. ilus, tab
Artigo em Português | VETINDEX | ID: vti-340757

RESUMO

We compared two models (with or without maternal effect) in the estimation of genetic parameters through Bayes Factor (BF) and the Deviance Information Criterion (DIC). Additionally, we evaluated the genetic, maternal and phenotypic trends in Tabapuã bovine growth characteristics in the state of Bahia. The model that included the maternal effect provided smaller BF values (167,629.2; 117,341.2 and 124,804.8) and DIC (174,550.0; 120,242.7 and 128,037.2) for weights at 205 (W205), 365 (W365) and 550 (W550) days of age, respectively. The average estimates, a posteriori, the direct and maternal heritability (0.33, 0.43 and 0.44) and (0.15, 0.14 and 0.16) for the three characteristics, respectively. Genetic trends for direct effect were 0.4415 and 0.3613kg/year for W205 and W365 and presented increases of 0.25 and 0.15% in the average characteristics of the year. The phenotypic trend for W205 was 0.7039kg/year. Maternal genetic trends for the three characteristics showed losses and indicate absence of selection matrices for good maternal ability. Despite the magnitude of the estimated direct and maternal heritability, they indicate genetic gain opportunities, genetic and phenotypic trends indicated few direct gains and no gains for maternal ability.(AU)


Compararam-se dois modelos (com ou sem o efeito materno) na estimativa de parâmetros genéticos por meio do fator de Bayes (FB) e do critério de informação da deviance (DIC). Adicionalmente, avaliaram-se as tendências genéticas, maternas e fenotípicas em características de crescimento de bovinos da raça Tabapuã do estado da Bahia. O modelo que incluiu o efeito materno proporcionou menores valores de FB (167629,2; 117341,2 e 124804,8) e DIC (174550,0; 120242,7 e 128037,2) para pesos aos 205 (P205), 365 (P365) e 550 (P550) dias de idade, respectivamente. As estimativas médias, a posteriori, das herdabilidades diretas e maternas foram 0,33; 0,43 e 0,44 e 0,15; 0,14 e 0,16 para as três características, respectivamente. As tendências genéticas para o efeito direto foram de 0,4415 e 0,3613kg/ano para P205 e P365 e representam incrementos de apenas 0,25 e 0,15% nas médias das características ao ano. As tendências genéticas maternas para as três características demonstraram perdas e indicam ausência de seleção de matrizes para boa habilidade materna. Apesar de existir variabilidade genética suficiente para justificar ganhos genéticos via seleção, estes e os ganhos fenotípicos foram pequenos, sugerindo necessidade de melhorias genéticas e ambientais.(AU)


Assuntos
Animais , Bovinos , Bovinos/genética , Fenótipo , Hereditariedade/genética , Teorema de Bayes
15.
Front Physiol ; 7: 690, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28119633

RESUMO

Studies on the yolk and albumen content in bird eggs, and the effects of variations in their relative loads in the phenotype of the birds, have revealed multiple consequences at different levels of biological organization, from biochemical traits to behavior. However, little is known about the effect of albumen variation on energetics performance during development and early ontogeny, despite the fact that variation in energy expenditure may have consequences in terms of fitness for both feral and domestic species. In this work, we evaluated experimentally whether variations in the content of albumen of Gallus gallus eggs could generate differences in metabolic rates during embryonic development. Additionally, we assessed changes in the activity of mitochondrial enzymes (cytochrome c oxidase and citrate synthase) in skeletal muscles and liver. Finally, we evaluated the success of hatching of these embryos and their metabolic rates (MR) post-hatching. The results revealed a significant reduction in MR in the last fifth of embryonic life, and reduced catabolic activities in the skeletal muscle of chicks hatched from albumen-removed eggs. However, the same group demonstrated an increase in catabolic activity in the liver, suggesting the existence of changes in energy allocation between tissues. Besides, we found a decrease in hatching success in the albumen-removed group, suggesting a negative effect of the lower albumen content on eggs, possibly due to lower catabolic activities in skeletal muscle. We also found a compensatory phenomenon in the first week after hatching, i.e., birds from albumen-removed eggs did not show a decrease in MR either at thermoneutral temperatures or at 10°C, compared to the control group. Collectively, our data suggest that a reduction in albumen may generate a trade-off between tissue metabolic activities, and may explain the differences in metabolic rates and hatching success, supporting the immediate adaptive response (IAR) hypothesis.

16.
R. cient. eletr. Med. Vet. ; 25: 1-15, jul. 2015. tab, ilus
Artigo em Português | VETINDEX | ID: vti-691004

RESUMO

Os peixes oferecem vantagens técnicas em relação aos demais vertebrados por apresentarem um sistema biológico menos especializado, permitindo certas manipulações que são impraticáveis em outros. Algumas das facilidades são: fecundação externa, alta fecundidade e diferenciação sexual controlável. Desta forma o desenvolvimento de novas tecnologias com o domínio da técnica de androgênese possibilita sua aplicação na conservação de espécies ameaçadas de extinção, revitalização e no melhoramento genéticos de espécies de interesse econômico e ambiental. (AU)


Fish offer technical advantages compared to other vertebrates because they have a less specialized biological system, allowing certain manipulations that are impractical in others. Some facilities are: external fertilization, high fertility and controllable sexual differentiation. Thus the development of new technologies in the field of androgenesis technique enables its application in conservation of endangered species, revitalization and genetic improvement of species of economic and environmental interests. (AU)


Assuntos
Animais , Fertilização , Fertilidade , Técnicas Reprodutivas , Peixes , Aquicultura
17.
Rev. cient. eletrônica med. vet ; 25: 1-15, jul. 2015. tab, ilus
Artigo em Português | VETINDEX | ID: biblio-1494186

RESUMO

Os peixes oferecem vantagens técnicas em relação aos demais vertebrados por apresentarem um sistema biológico menos especializado, permitindo certas manipulações que são impraticáveis em outros. Algumas das facilidades são: fecundação externa, alta fecundidade e diferenciação sexual controlável. Desta forma o desenvolvimento de novas tecnologias com o domínio da técnica de androgênese possibilita sua aplicação na conservação de espécies ameaçadas de extinção, revitalização e no melhoramento genéticos de espécies de interesse econômico e ambiental.


Fish offer technical advantages compared to other vertebrates because they have a less specialized biological system, allowing certain manipulations that are impractical in others. Some facilities are: external fertilization, high fertility and controllable sexual differentiation. Thus the development of new technologies in the field of androgenesis technique enables its application in conservation of endangered species, revitalization and genetic improvement of species of economic and environmental interests.


Assuntos
Animais , Fertilidade , Fertilização , Peixes , Técnicas Reprodutivas , Aquicultura
18.
Ciênc. rural ; Ciênc. rural (Online);44(1): 111-116, Jan. 2014. tab
Artigo em Português | LILACS | ID: lil-697033

RESUMO

Objetivou-se nesse trabalho, estimar os parâmetros genéticos para características de crescimento em ovinos da raça Santa Inês através do Método da Máxima Verossimilhança Restrita (REML). Os componentes de (co)variâncias e os parâmetros genéticos foram estimados pelo Software MTDFREML (Multiple Trait Derivative-Free Restricted Maximum Likelihood). As características avaliadas em modelos uni e bicaracterística foram: peso ao nascimento (PN) e peso ao desmame (P90). Além dos efeitos fixos de sexo, grupo contemporâneo e tipo de parto, foram utilizados os seguintes efeitos aleatórios: efeito genético aditivo direto, efeito genético aditivo materno e efeito residual. As estimativas de herdabilidade aditiva direta para PN foram 0,20 e 0,21, para os modelos uni e bicaracterística, respectivamente. As estimativas de herdabilidade aditiva direta para P90 foram 0,04 e 0,07, para os modelos uni e bicaracterística, respectivamente. A correlação genética entre PN e P90 foi de 0,11, indicando que ambas as características devem ser trabalhadas simultaneamente.


The objective of this study is to estimate genetic parameters for growth traits in sheep Santa Ines breed by Restricted Maximum Likelihood (REML). The (co)variance components and genetic parameters were estimated by MTDFREML Software (Multiple Trait Derivative-Free Restricted Maximum Likelihood). The characteristics evaluated in single and two-trait models were: birth weight (BW) and weaning weight (WW). In addition to the fixed effects of sex, contemporary group and parity type, we used the following random effects: direct genetic effect, maternal additive genetic and residual effects. The direct additive heritability estimates for BW were 0.20 and 0.21 for single and two-trait models, respectively. Heritability estimates for direct additive WW were 0.04 and 0.07 for single and two-trait models, respectively. The genetic correlation between BW and WW was 0.11, indicating that both traits should be worked on simultaneously.

19.
Ci. Rural ; 44(1): 111-116, jan. 2014. tab
Artigo em Português | VETINDEX | ID: vti-324150

RESUMO

Objetivou-se nesse trabalho, estimar os parâmetros genéticos para características de crescimento em ovinos da raça Santa Inês através do Método da Máxima Verossimilhança Restrita (REML). Os componentes de (co)variâncias e os parâmetros genéticos foram estimados pelo Software MTDFREML (Multiple Trait Derivative-Free Restricted Maximum Likelihood). As características avaliadas em modelos uni e bicaracterística foram: peso ao nascimento (PN) e peso ao desmame (P90). Além dos efeitos fixos de sexo, grupo contemporâneo e tipo de parto, foram utilizados os seguintes efeitos aleatórios: efeito genético aditivo direto, efeito genético aditivo materno e efeito residual. As estimativas de herdabilidade aditiva direta para PN foram 0,20 e 0,21, para os modelos uni e bicaracterística, respectivamente. As estimativas de herdabilidade aditiva direta para P90 foram 0,04 e 0,07, para os modelos uni e bicaracterística, respectivamente. A correlação genética entre PN e P90 foi de 0,11, indicando que ambas as características devem ser trabalhadas simultaneamente.(AU)


The objective of this study is to estimate genetic parameters for growth traits in sheep Santa Ines breed by Restricted Maximum Likelihood (REML). The (co)variance components and genetic parameters were estimated by MTDFREML Software (Multiple Trait Derivative-Free Restricted Maximum Likelihood). The characteristics evaluated in single and two-trait models were: birth weight (BW) and weaning weight (WW). In addition to the fixed effects of sex, contemporary group and parity type, we used the following random effects: direct genetic effect, maternal additive genetic and residual effects. The direct additive heritability estimates for BW were 0.20 and 0.21 for single and two-trait models, respectively. Heritability estimates for direct additive WW were 0.04 and 0.07 for single and two-trait models, respectively. The genetic correlation between BW and WW was 0.11, indicating that both traits should be worked on simultaneously.(AU)


Assuntos
Funções Verossimilhança , Ovinos , Modelos Animais
20.
Semina ciênc. agrar ; 34(1): 359-366, 2013.
Artigo em Português | LILACS-Express | VETINDEX | ID: biblio-1499123

RESUMO

The objective of this study was to analyze a data set with 205 records from a Nellore breed cattle, evaluating the influence of environmental factors on weaning weight adjusted to 205 days of age (W205), preweaning average daily gain (ADG) and number of days to gain 160 kg (D160). The data came from a farm in São Paulo State and were collected from 2007 to 2010. The statistical analysis was accomplished using the least squares method, with a model that included the fixed effects of contemporary group, sire and cow age at calving, and error as random effect. The same model was used to analyze 124 records of weight adjusted to 90 days of age (W90). The effects of contemporary group and sire were significant. The cow age at calving was not significant for any performance trait analyzed, except for W90 (P 0.05). The estimated means were 140.67 ± 20.08 kg, 0.539 ± 0.097 kg/day and 306.42 ± 55.84 days, for W205, ADG e D160, respectively. The weightless calves were born in February (115.65 kg) and the heaviest in July (156.18 kg). The males were 5.8% superior than females. The importance of non genetic effects indicates the need to consider them when estimating genetic parameters and breeding values for selection purpose.


O objetivo deste trabalho foi analisar os dados de pesagens de animais da raça Nelore Mocha, provenientes de um rebanho no Estado de São Paulo no período de 2007 a 2010, avaliando a influência de fatores ambientais sobre as características pré-desmama observadas. Foram utilizadas 205 observações de peso à desmama ajustado para 205 dias de idade (P205), ganho médio diário do nascimento à desmama (GMD) e dias para o animal ganhar 160 kg do nascimento à desmama (D160) pelo Método dos Quadrados Mínimos, utilizando-se um modelo contendo os efeitos fixos de grupo de contemporâneo (data de nascimento, mês de nascimento, sexo e data juliana de desmama), pai e idade da vaca ao parto e, como efeito aleatório, o erro. Utilizando o mesmo modelo, foram analisadas 124 observações de peso ajustado aos 90 dias de idade (P90). Os efeitos de grupo de contemporâneo (GC) e de pai influenciaram significativamente todas as características estudadas. Para P90 verificou-se o efeito da idade da vaca ao parto (P 0,05). As médias e desvios padrão observados foram de 140,67 ± 20,08 kg, 0,539 ± 0,097 kg/dia e 306,42 ± 55,84 dias, para P205, GMD e D160, respectivamente. Os animais mais leves foram os nascidos em fevereiro (115,65 kg) e os mais pesados em julho (156,18 kg). Os machos apresentaram valores de médias estimadas para GC de 5,8% superiores que as fêmeas. A importância dos efeitos não genético

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