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1.
Res Vet Sci ; 166: 105099, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38091815

RESUMEN

This study aimed to assess the predictive ability of parametric models and artificial neural network method for genomic prediction of the following indicator traits of resistance to gastrointestinal nematodes in Santa Inês sheep: packed cell volume (PCV), fecal egg count (FEC), and Famacha© method (FAM). After quality control, the number of genotyped animals was 551 (PCV), 548 (FEC), and 565 (FAM), and 41,676 SNP. The average prediction accuracy (ACC) calculated by Pearson correlation between observed and predicted values and mean squared errors (MSE) were obtained using genomic best unbiased linear predictor (GBLUP), BayesA, BayesB, Bayesian least absolute shrinkage and selection operator (BLASSO), and Bayesian regularized artificial neural network (three and four hidden neurons, BRANN_3 and BRANN_4, respectively) in a 5-fold cross-validation technique. The average ACC varied from moderate to high according to the trait and models, ranging between 0.418 and 0.546 (PCV), between 0.646 and 0.793 (FEC), and between 0.414 and 0.519 (FAM). Parametric models presented nearly the same ACC and MSE for the studied traits and provided better accuracies than BRANN. The GBLUP, BayesA, BayesB and BLASSO models provided better accuracies than the BRANN_3 method, increasing by around 23% for PCV, and 18.5% for FEC. In conclusion, parametric models are suitable for genome-enabled prediction of indicator traits of resistance to gastrointestinal nematodes in sheep. Due to the small differences in accuracy found between them, the use of the GBLUP model is recommended due to its lower computational costs.


Asunto(s)
Genoma , Nematodos , Ovinos , Animales , Teorema de Bayes , Nematodos/genética , Genotipo , Fenotipo , Redes Neurales de la Computación , Modelos Genéticos , Polimorfismo de Nucleótido Simple
2.
Braz. j. biol ; 82: e243114, 2022. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1278478

RESUMEN

Littoraria angulifera (Lamarck, 1822) is an estuarine gastropod of tropical occurrence, which lives mainly on trunks of mangrove tree species. This study aimed to evaluate the population attributes of this species, such as abundance, space-time distribution, sex ratio and recruitment in mangroves in Bahia State, northeastern Brazil. The specimens were collected monthly throughout 2018, on trunks of the red mangrove Rhizophora mangle L. at two heights and on two horizontal levels. Specimens that were on the marine grass Spartina alterniflora Loisel were also collected. After counting, biometrics and sexing, the specimens were returned alive to the environment. The average size and weight of L. angulifera was higher (p<0.05) in places with taller and less sparse trees and the vertical distribution on the trunks showed a preference for strata close to the soil. Both results are related to shading and protection against desiccation. Females were more abundant than males, at an approximate sex ratio F: M of 1.4: 1. Recruits were observed throughout the period, showing continuous reproduction of the species with a recruitment peak in spring (September to November). The study revealed the importance of keep the mangroves intact to allow the maintenance of the natural stocks of the species.


Littoraria angulifera (Lamarck, 1822) é um gastrópode estuarino, de ocorrência tropical, que vive principalmente sobre troncos de espécies arbóreas de mangue. Este estudo teve como objetivo avaliar os atributos populacionais dessa espécie, como abundância, distribuição espaço-temporal, razão sexual e recrutamento em manguezais do estado da Bahia, nordeste do Brasil. Os espécimes foram coletados mensalmente ao longo de 2018, em troncos do mangue vermelho Rhizophora mangle L. em duas alturas e em dois níveis horizontais. Também foram coletados espécimes que estavam na grama marinha Spartina alterniflora Loisel. Após contagem, biometria e sexagem, os espécimes foram devolvidos vivos ao ambiente. O tamanho e peso médios de L. angulifera foram maiores (p<0,05) em locais com árvores mais altas e menos esparsas e a distribuição vertical nos troncos mostrou preferência por estratos próximos ao solo. Ambos os resultados estão relacionados ao sombreamento e proteção contra a dessecação. As fêmeas foram mais abundantes que os machos, em uma proporção sexual aproximada F: M de 1,4: 1. Recrutas foram observados ao longo do período, mostrando reprodução contínua da espécie, com um pico de recrutamento na primavera (setembro a novembro). O estudo revelou a importância de manter os manguezais intactos para permitir a manutenção dos estoques naturais da espécie.


Asunto(s)
Animales , Masculino , Femenino , Rhizophoraceae , Gastrópodos , Árboles , Brasil , Densidad de Población
3.
Braz. j. biol ; 82: 1-10, 2022. map, tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1468528

RESUMEN

Littoraria angulifera (Lamarck, 1822) is an estuarine gastropod of tropical occurrence, which lives mainly on trunks of mangrove tree species. This study aimed to evaluate the population attributes of this species, such as abundance, space-time distribution, sex ratio and recruitment in mangroves in Bahia State, northeastern Brazil. The specimens were collected monthly throughout 2018, on trunks of the red mangrove Rhizophora mangle L. at two heights and on two horizontal levels. Specimens that were on the marine grass Spartina alterniflora Loisel were also collected. After counting, biometrics and sexing, the specimens were returned alive to the environment. The average size and weight of L. angulifera was higher (p<0.05) in places with taller and less sparse trees and the vertical distribution on the trunks showed a preference for strata close to the soil. Both results are related to shading and protection against desiccation. Females were more abundant than males, at an approximate sex ratio F: M of 1.4: 1. Recruits were observed throughout the period, showing continuous reproduction of the species with a recruitment peak in spring (September to November). The study revealed the importance of keep the mangroves intact to allow the maintenance of the natural stocks of the species.


Littoraria angulifera (Lamarck, 1822) é um gastrópode estuarino, de ocorrência tropical, que vive principalmente sobre troncos de espécies arbóreas de mangue. Este estudo teve como objetivo avaliar os atributos populacionais dessa espécie, como abundância, distribuição espaço-temporal, razão sexual e recrutamento em manguezais do estado da Bahia, nordeste do Brasil. Os espécimes foram coletados mensalmente ao longo de 2018, em troncos do mangue vermelho Rhizophora mangle L. em duas alturas e em dois níveis horizontais. Também foram coletados espécimes que estavam na grama marinha Spartina alterniflora Loisel. Após contagem, biometria e sexagem, os espécimes foram devolvidos vivos ao ambiente. O tamanho e peso médios de L. angulifera foram maiores (p<0,05) em locais com árvores mais altas e menos esparsas e a distribuição vertical nos troncos mostrou preferência por estratos próximos ao solo. Ambos os resultados estão relacionados ao sombreamento e proteção contra a dessecação. As fêmeas foram mais abundantes que os machos, em uma proporção sexual aproximada F: M de 1,4: 1. Recrutas foram observados ao longo do período, mostrando reprodução contínua da espécie, com um pico de recrutamento na primavera (setembro a novembro). O estudo revelou a importância de manter os manguezais intactos para permitir a manutenção dos estoques naturais da espécie.


Asunto(s)
Animales , Gastrópodos/crecimiento & desarrollo , Humedales , Densidad de Población
4.
Braz. j. biol ; 822022.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468715

RESUMEN

Abstract Littoraria angulifera (Lamarck, 1822) is an estuarine gastropod of tropical occurrence, which lives mainly on trunks of mangrove tree species. This study aimed to evaluate the population attributes of this species, such as abundance, space-time distribution, sex ratio and recruitment in mangroves in Bahia State, northeastern Brazil. The specimens were collected monthly throughout 2018, on trunks of the red mangrove Rhizophora mangle L. at two heights and on two horizontal levels. Specimens that were on the marine grass Spartina alterniflora Loisel were also collected. After counting, biometrics and sexing, the specimens were returned alive to the environment. The average size and weight of L. angulifera was higher (p 0.05) in places with taller and less sparse trees and the vertical distribution on the trunks showed a preference for strata close to the soil. Both results are related to shading and protection against desiccation. Females were more abundant than males, at an approximate sex ratio F: M of 1.4: 1. Recruits were observed throughout the period, showing continuous reproduction of the species with a recruitment peak in spring (September to November). The study revealed the importance of keep the mangroves intact to allow the maintenance of the natural stocks of the species.


Resumo Littoraria angulifera (Lamarck, 1822) é um gastrópode estuarino, de ocorrência tropical, que vive principalmente sobre troncos de espécies arbóreas de mangue. Este estudo teve como objetivo avaliar os atributos populacionais dessa espécie, como abundância, distribuição espaço-temporal, razão sexual e recrutamento em manguezais do estado da Bahia, nordeste do Brasil. Os espécimes foram coletados mensalmente ao longo de 2018, em troncos do mangue vermelho Rhizophora mangle L. em duas alturas e em dois níveis horizontais. Também foram coletados espécimes que estavam na grama marinha Spartina alterniflora Loisel. Após contagem, biometria e sexagem, os espécimes foram devolvidos vivos ao ambiente. O tamanho e peso médios de L. angulifera foram maiores (p 0,05) em locais com árvores mais altas e menos esparsas e a distribuição vertical nos troncos mostrou preferência por estratos próximos ao solo. Ambos os resultados estão relacionados ao sombreamento e proteção contra a dessecação. As fêmeas foram mais abundantes que os machos, em uma proporção sexual aproximada F: M de 1,4: 1. Recrutas foram observados ao longo do período, mostrando reprodução contínua da espécie, com um pico de recrutamento na primavera (setembro a novembro). O estudo revelou a importância de manter os manguezais intactos para permitir a manutenção dos estoques naturais da espécie.

5.
Braz J Biol ; 82: e243114, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34133568

RESUMEN

Littoraria angulifera (Lamarck, 1822) is an estuarine gastropod of tropical occurrence, which lives mainly on trunks of mangrove tree species. This study aimed to evaluate the population attributes of this species, such as abundance, space-time distribution, sex ratio and recruitment in mangroves in Bahia State, northeastern Brazil. The specimens were collected monthly throughout 2018, on trunks of the red mangrove Rhizophora mangle L. at two heights and on two horizontal levels. Specimens that were on the marine grass Spartina alterniflora Loisel were also collected. After counting, biometrics and sexing, the specimens were returned alive to the environment. The average size and weight of L. angulifera was higher (p<0.05) in places with taller and less sparse trees and the vertical distribution on the trunks showed a preference for strata close to the soil. Both results are related to shading and protection against desiccation. Females were more abundant than males, at an approximate sex ratio F: M of 1.4: 1. Recruits were observed throughout the period, showing continuous reproduction of the species with a recruitment peak in spring (September to November). The study revealed the importance of keep the mangroves intact to allow the maintenance of the natural stocks of the species.


Asunto(s)
Gastrópodos , Rhizophoraceae , Animales , Brasil , Femenino , Masculino , Densidad de Población , Árboles
7.
Braz. j. biol ; 80(2): 424-430, Apr.-June 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1132364

RESUMEN

Abstract The gastropod Littoraria angulifera (Littorinidae) is an exclusively estuarine mollusk with Neotropical anfiatlantic distribution. Recent studies indicate a possible use of the species as bioindicator. The aim of this study was to analyze the shell height, as well as to perform a morphometric analysis of the reproductive apparatus of L. angulifera collected in 22 sampling points located between latitudes 13º54'S and 15º44'S in the South Atlantic, State of Bahia, Northeastern Brazil. The specimens were obtained in different estuarine environments including mangroves, as well as on rocks and concrete walls in places close to ports, shipyards and berths during January and February 2014. All specimens (n = 880) were analyzed regarding the sex and shell height/morphology, 440 were analyzed about the reproductive apparatus morphometry and 15 in histological description. The average shell height of animals from artificial substrates in nautical areas was lower (p<0.05) than the animals from mangroves, mainly in preserved areas, evidencing relation with human impacts and desiccation. The morphometric analysis of L. angulifera reproductive tract allowed us to conclude that the length of prostate in males and of palial oviduct in females may be useful in the reproductive evaluation of the species.


Resumo O gastrópode Littoraria angulifera (Littorinidae) é um molusco exclusivamente estuarino com distribuição anfiatlântica neotropical. Estudos recentes indicam um possível uso dessa espécie como bioindicadora. No presente estudo teve-se por objetivos analisar a altura da concha, assim como realizar uma análise morfométrica do aparato reprodutor de L. angulifera coletada em 22 pontos amostrais localizados entre as latitudes 13º54'S e 15º44'S no Atlântico Sul, Estado da Bahia, Nordeste do Brasil. Os exemplares foram obtidos em diferentes ambientes estuarinos, incluindo manguezais, assim como sobre rochas e paredes de concreto em lugares próximos a portos, estaleiros e atracadouros, durante janeiro e fevereiro de 2014. Todos os espécimes (n = 880) foram analisados quanto à morfologia/ altura da concha e sexo, 440 quanto à morfometria do aparelho reprodutor e 15 em descrição histológica. A média de altura da concha de animais de substratos artificiais em áreas náuticas foi menor (p<0,05) do que de animais de manguezais, principalmente de áreas preservadas, evidenciando relação com o impacto antrópico e a dessecação. A análise morfométrica do trato reprodutivo de L. angulifera levou à conclusão que o comprimento da próstata em machos e do oviduto palial em fêmeas pode ser útil na avaliação reprodutiva da espécie.


Asunto(s)
Animales , Masculino , Femenino , Gastrópodos , Reproducción , Brasil
8.
Braz J Biol ; 80(2): 424-430, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31482972

RESUMEN

The gastropod Littoraria angulifera (Littorinidae) is an exclusively estuarine mollusk with Neotropical anfiatlantic distribution. Recent studies indicate a possible use of the species as bioindicator. The aim of this study was to analyze the shell height, as well as to perform a morphometric analysis of the reproductive apparatus of L. angulifera collected in 22 sampling points located between latitudes 13º54'S and 15º44'S in the South Atlantic, State of Bahia, Northeastern Brazil. The specimens were obtained in different estuarine environments including mangroves, as well as on rocks and concrete walls in places close to ports, shipyards and berths during January and February 2014. All specimens (n = 880) were analyzed regarding the sex and shell height/morphology, 440 were analyzed about the reproductive apparatus morphometry and 15 in histological description. The average shell height of animals from artificial substrates in nautical areas was lower (p<0.05) than the animals from mangroves, mainly in preserved areas, evidencing relation with human impacts and desiccation. The morphometric analysis of L. angulifera reproductive tract allowed us to conclude that the length of prostate in males and of palial oviduct in females may be useful in the reproductive evaluation of the species.


Asunto(s)
Gastrópodos , Animales , Brasil , Femenino , Masculino , Reproducción
9.
Parasitology ; 146(5): 580-587, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30486907

RESUMEN

The clinical manifestation and course of Leishmania infections depend on factors such as species, virulence and host-immunity. Although trypanosomatids are considered to have clonal propagation, genetic hybridization has produced successful natural hybrid lineages. Hybrids displaying strong selective advantages may have an impact on pathogenesis and the eco-epidemiology of leishmaniasis. Thus, characterization of phenotypic properties of Leishmania hybrids could bring significant insight into the biology, infectivity, pathogenicity and transmission dynamics of these atypical strains. The present study focuses on phenotypic features and survival capacity of Leishmania infantum/Leishmania major hybrid isolates as compared with representative putative parental species, L. infantum and L. major. In vitro assays (growth kinetics, susceptibility to different conditions) and in vivo infection (parasite detection and histopathological alterations) showed that hybrids present higher growth capacity and decreased susceptibility to reactive oxygen species. Furthermore, evaluation of infected spleen tissue suggests that hybrids induce a stronger immune reaction than their putative parents, leading to the development of white pulp hyperplasia in B-lymphocyte compartments. Overall, these hybrids have shown high plasticity in terms of their general behaviour within the different phenotypic parameters, suggesting that they might have acquired genetic features conferring different mechanisms to evade host cells.


Asunto(s)
Hibridación Genética , Leishmania infantum/fisiología , Leishmania major/fisiología , Leishmaniasis/parasitología , Longevidad , Fenotipo , Animales , Femenino , Leishmania infantum/crecimiento & desarrollo , Leishmania major/crecimiento & desarrollo , Ratones , Ratones Endogámicos BALB C
10.
J Microencapsul ; 34(6): 560-570, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28805476

RESUMEN

The aim of this work was to obtain microencapsulated stable Aspergillus niger peptidases by post fermentation spray drying. The enzymatic extract was evaluated before and after spray drying microencapsulation to verify the effects of five different process parameters on the extract enzymatic activity, i.e. air flow, extract feed rate, drying temperature, homogenising time and weight ratio of extract to encapsulation material. The optimal conditions were determined by desirability functions and experimentally confirmed. Additionally, the stability of the microparticles was assessed during 60 days at 4 °C, 25 °C and 40 °C. The results revealed that the microparticles stored at 4 °C retained approximately 100% of their proteolytic activity at nine days of storage. Considering the industrial adaptation of the bioprocess and the prospect of commercial application of the proteases, the evaluation of different parameters for drying enzymes is required as a valuable alternative to obtain biotechnological products with high added value.


Asunto(s)
Aspergillus niger/enzimología , Fibras de la Dieta/metabolismo , Fermentación , Residuos Industriales , Péptido Hidrolasas/química , Composición de Medicamentos , Estabilidad de Enzimas
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