Abstract: The objective of this work was to estimate genetic parameters for bird carcass and meat quality traits, as well as to explore the genetic patterns of the breeding values of this population using cluster analyses. Data from 1,846 birds were used to estimate the genetic parameters of production and quality traits using the multiple-trait animal model, and cluster analyses were performed. The heritability estimates ranged from 0.08± 0.03 for meat pH measured 24 hours after slaughter to 0.85± 0.09 for body weight. The genetic correlations between production traits were high and positive. The genetic correlations between meat quality traits were low and were not informative due to the high standard errors (same magnitudes as those of the genetic correlations). The genetic correlations between meat production and quality traits were negative, except between production traits and meat lightness intensity. Based on breeding values (EBVs), the evaluated population can be divided into four groups through cluster analyses, and one group is suitable for selection because the birds presented EBVs above and around the average of the population, respectively, for production and quality traits. Therefore, it is possible to obtain genetic gains for production-related traits without decreasing meat quality.
Resumo: O objetivo deste trabalho foi estimar os parâmetros genéticos para características de carcaça e qualidade da carne de aves, bem como explorar o perfil dos valores genéticos desta população, com uso de análises de agrupamento. Foram utilizados dados de 1.846 aves para estimar os parâmetros genéticos de características de produção e qualidade por meio do modelo animal multicaracterística, e foram realizadas análises de agrupamento. As estimativas de herdabilidade variaram de 0,08± 0,03 para o pH da carne medido 24 horas após o abate a 0,85± 0,09 para o peso corporal. As correlações genéticas entre as características de produção foram altas e positivas. Já as correlações genéticas entre as características de qualidade da carne foram baixas e não foram informativas devido aos altos erros-padrão (mesmas magnitudes que as das correlações genéticas). As correlações genéticas entre as características de produção e de qualidade da carne foram negativas, exceto entre as características de produção e o teor de luminosidade da carne. Com base nos valores genéticos (VGs), a população avaliada pode ser dividida em quatro grupos por meio da análise de agrupamento, e um dos grupos é mais adequado para seleção, uma vez que as aves apresentaram VGs acima e em torno da média da população, respectivamente, para as características de produção e de qualidade da carne. Assim, é possível obter ganhos genéticos para características relacionadas à produção sem diminuir a qualidade da carne.
Lectins are carbohydrate-binding proteins of non-imune origin. This group of proteins is distributed widely in nature and they have been found in viruses, microorganisms, plants and animals. Lectins of plants have been isolated and characterized according to their chemical, physical-chemical, structural and biological properties. Among their biological activities, we can stress its fungicidal action. It has been previously described the effect of the lectins Dviol, DRL, ConBr and LSL obtained from the seeds of leguminous plants on the growth of yeasts isolated from vaginal secretions. In the present work the experiments were carried out in microtiter plates and the results interpreted by both methods: visual observations and a microplate reader at 530nm. The lectin concentrations varied from 0.5 to 256µg/mL, and the inoculum was established between 65-70% of trammitance. All yeast samples isolated from vaginal secretion were evaluated taxonomically, where were observed macroscopic and microscopic characteristics to each species. The LSL lectin did not demonstrate any antifungal activity to any isolate studied. The other lectins DRL, ConBr and DvioL, showed antifungal potential against yeast isolated from vaginal secretion. These findings offering offer a promising field of investigation to develop new therapeutic strategies against vaginal yeast infections, collaborating to improve women's health.
The objective of this study was to estimate genetic and phenotypic correlations of body weight at 6 weeks of age (BW6), as well as final carcass yield, and moisture, protein, fat and ash contents, using data from 3,422 F2 chickens originated from reciprocal cross between a broiler and a layer line. Variance components were estimated by the REML method, using animal models for evaluating random additive genetic and fixed contemporary group (sex, hatch and genetic group) effects. The heritability estimates (h²) for BW6, carcass yield and percentage of carcass moisture were 0.31 ± 0.07, 0.20 ± 0.05 and 0.33 ± 0.07, respectively. The h² for the percentages of protein, fat and ash on a dry matter basis were 0.48 ± 0.09, 0.55 ± 0.10 and 0.36 ± 0.08, respectively. BW6 had a positive genetic correlation with fat percentage in the carcass, but a negative one with protein and ash contents. Carcass yield, thus, appears to have only low genetic association with carcass composition traits. The genetic correlations observed between traits, measured on a dry matter basis, indicated that selection for carcass protein content may favor higher ash content and a lower percentage of carcass fat.