RESUMEN

Age at first calving (AFC) is a measure of sexual maturity associated with the start of productive life of dairy animals. Additionally, a lower AFC reduces the generation interval and early culling of females. However, AFC has low heritability, making it a trait highly influenced by environmental factors. In this scenario, one way to improve the reproductive performance of buffalo cows is to select robust animals according to estimated breeding value (EBV) using models that include genotype-environment interaction (GEI) with the application of reaction norm models (RNMs). This can be achieved by understanding the genomic basis related to GEI of AFC. Thus, in this study, we aimed to predict EBV considering GEI via the RNM and identify candidate genes related to this component in dairy buffaloes through genome-wide association studies (GWAS). We used 1795 AFC records from three Murrah buffalo herds and formed environmental gradients (EGs) from contemporary group solutions obtained from genetic analysis of 270-day cumulative milk yield. Heritability estimates ranged from 0.15 to 0.39 along the EG. GWAS of the RNM slope parameter identified important genomic regions. The genomic window that explained the highest percentage of genetic variance of the slope (0.67%) was located on BBU1. After functional analysis, five candidate genes were detected, involved in two biological processes. The results suggested the existence of a GEI for AFC in Murrah buffaloes, with reclassification of animals when different environmental conditions were considered. The inclusion of genomic information increased the accuracy of breeding values for the intercept and slope of the reaction norm. GWAS analysis suggested that important genes associated with the AFC reaction norm slope were possibly also involved in biological processes related to lipid metabolism and immunity.

RESUMEN

This study aimed to compare AFM1 occurrence in different cheese types produced by organic and conventional systems; and to evaluate the risk of food exposure to AFM1. A total of 176 commercial cheeses of 17 types were analyzed, 84 of organic and 92 of conventional production. Determination of AFM1 was performed by high- performance liquid chromatography (HPLC), being detected in 30.5% of samples, with 4.8% of organic cheese samples presenting quantifiable AFM1 values between 0.88 and 1.50 µg/kg. On the other hand, 4.3% of conventional cheese samples with values between 0.79 and 6.70 µg/kg. Two conventional cheese samples were above the limit of AFM1 allowed for cheeses by the Brazilian legislation. No statistical difference were found between organic and conventional cheeses regarding the occurrence (p = 0.1780) and concentration of AFM1 (p = 0.1810), according to the Chi-square and the T test, respectively. Estimated daily intake (EDI) and hazard index (HI) of dietary exposure to AFM1 were 0.26 ng/kg/day and 1.28 ng/kg/day, respectively, for conventional cheese samples, and 0.09 ng/kg/day and 0.47 ng/kg/day for organic samples, with no statistical difference for EDI (p = 0.1729) and HI (p = 0.1802) between the two production systems. Comparison between several cheese types from conventional and organic systems indicated that AFM1 is an obstacle to dairy production. Control and prevention of AFM1 contamination, as well as detoxification methods in the final products, are necessary. In the case of organic products, additional research is needed in order to determine which control and detoxification methods should be allowed in this production system.

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RESUMEN

The aim of this study was to evaluate the population structure of Brazilian buffaloes using of pedigree information. The pedigree used in the analyses included records of 16,915 animals. The population parameters were obtained through the ENDOG software. The estimates of mean of inbreeding (F) and average relatedness (AR) coefficients were 3.22% and 5.99%, respectively. The average generation interval was 6.39 years. The effective number of founders and ancestors was 28 and 22, respectively. In this study, we concluded that the selection of individuals with lower AR is necessary to avoid an increase in matings between inbreeding individuals in this population, in order to obtain greater genetic gain by selection.

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RESUMEN

Pantaneiro cattle (Bos taurus taurus) is a breed locally adapted to the Brazilian Pantanal. Local breeds are essential for the quality production of organic systems based on planned grazing practices, because of their results in resilient and productive ecosystems, enhancing biodiversity. This study aimed to evaluate the performance of Pantaneira primiparous cows, and systems with reduced use of concentrate, simulating organic production conditions. Five animals, with an average body weight of 396.2 ± 43.5 kg, were kept in individual continuous grazing regimes and supplemented with different concentrate levels (1.2%, 0.9%, 0.6%, 0.3%, and 0.0% of body weight). The animals were allocated at random in a 5 × 5 Latin square design repeated twice during the study time. The cows had a low dry matter and nutrient intake with a reduction in concentrate level, with improvement in neutral detergent fiber digestibility and a reduction in total nutrient digestibility. No changes were observed in plasma glucose levels or urea excretion, but the plasma urea nitrogen decreased with reductions in concentrate levels. There was a reduction in milk yield, but the energy-corrected milk was not affected by the reduction in concentrate levels; furthermore, the milk yield efficiency was not affected. The milk fat content improved with the reduction in concentrate levels. The Pantaneira breed has the genetic potential for the maintenance of competitive production and quality in organic systems.

RESUMEN

Growth traits are important for the profitability of buffalo breeding systems, since in general, these animals are raised both for meat and milk. In this study, the single-step genomic BLUP method was employed to prospect the genomic regions' associated with weight at standard ages of 100, 210, 365, and 550 days in a buffalo population, aiming to identify genes with stronger expression for those characteristics. We found 6, 1, 2, and 5 SNPs significantly associated (p value < 10-5) with weight at 100, 210, 365, and 550 days of age, respectively, where those SNPs respectively explained 0.164, 0.040, 0.044, and 0.213% of the additive variance of each trait. SNP AX-85099682 (BBU24) was significant for weight at 100, 210, and 365 days, indicating the existence of a possible QTL affecting the initial growth rate of buffaloes. All told, eight genes (CBLB, TRNAG-UCC, GADD45B, LOC112583811, MGAT4C, KCNMA1, SLC5A2, and TGFB1I1) were identified as candidates for the growth traits of buffaloes. However, molecular and gene expression studies are necessary to validate these genes for subsequent use in programs for genetic improvement of the species.

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SUMMARY Objective to evaluate the effect of the inclusion of levels of crude Glycerin in the feeding of lambs in the biometric characteristics and testicular histological. 24 lambs were neutered, not confined with 93.79 ± 5.73 days of age and body weight of 20.22 ± 2.84 kg. The treatments tested were: 0; 2.5; 5.0 and 7.5% of crude Glycerin injection in dry matter of diet in place of maize. The animals were slaughtered using the criteria in body condition score of 2.5 to 3.5 on a scale ranging from 1 to 5, and the variables evaluated were the initial weight, final weight, hot carcass weight, fat cover thickness, body condition, and the biometric parameters: testicular weight, scrotal perimeter in the scrotum, testicle weight left and right volume of right and left testicle, testicular testicular length width, seminiferous tubule diameter and height of germinal epithelium. There was no significant influence of crude Glycerin levels on any of the variables analyzed, also there was no correlation between the features assessed with body condition. Positive correlations were observed between hot carcass weight and fat thickness (r=0,57, p= p 0,05)). There was positive correlation (r=0,55, p= p 0,05)) between scrotal perimeter and body weight. The tubule diameter (r=0,47, p=p 0,05) and height of the seminiferous epithelium (r=0,62, p=p 0,05) were correlated with testicular volume. The inclusion of increasing levels of crude Glycerin in the feeding of lambs Pantaneiros, did not influence the biometric characteristics and testicular histométrics of animals.

RESUMO Objetivou-se avaliar o efeito da inclusão de níveis de glicerina bruta na alimentação de cordeiros nas características biométricas e histológicas testiculares. Foram utilizados 24 cordeiros não castrados, confinados com 93,79 ± 5,73 dias de idade e peso corporal de 20,22±2,84kg. Os tratamentos testados foram: 0; 2,5; 5,0 e 7,5% de inclusão de glicerina bruta na matéria seca da dieta em substituição ao milho. Os animais foram abatidos usando a condição corporal como critério em escore de 2,5 a 3,5, em uma escala que varia de 1 a 5, sendo que as variáveis avaliadas foram o peso inicial, peso final, peso de carcaça quente, espessura de gordura de cobertura, condição corporal, e os parâmetros biométricos testiculares: perímetro escrotal, peso testicular no escroto, peso dos testículos direito e esquerdo, volume dos testículos direito e esquerdo, largura testicular, comprimento testicular, diâmetro de túbulo seminífero e altura de epitélio germinativo. Não houve influência significativa dos níveis de glicerina bruta sobre nenhuma das variáveis analisadas, também não houve correlação entre as características avaliadas com a condição corporal. Foram observadas correlações positivas entre o peso de carcaça quente e espessura de gordura de cobertura (r=0,57, p 0,05). Houve correlação positiva (r=0,55, p 0,05)) entre perímetro escrotal e peso corporal. O diâmetro do túbulo (r=0,47, p 0,05) e a altura do epitélio seminíferos (r=0,62, p 0,05) estiveram correlacionados com o volume testicular. A inclusão de níveis crescentes de glicerina bruta na alimentação de cordeiros Pantaneiros até 7,5% de inclusão não influencia nas características biométricas e histométricas testiculares dos animais.

RESUMEN

SUMMARY The objective was to assess the effect of inclusion of crude glycerin (CG) replacing corn in the diet of feedlot Pantaneiro lambs on the non-carcass components, regional and tissue composition, and carcass traits. Were used 24 not castrated males, in a completely randomized design with four treatments (0, 2.5, 5.0 and 7.5% of CG on DM basis). There was no effect of GB inclusion on non-carcass components. There was a quadratic effect for hot carcass weight, with lower value to 2.5% of CG. Regional and tissue composition of the carcass was not affected by the substitution of corn by CG. The tissue composition of shoulder and leg and instrumental traits of the shoulder were not affected by CG. There was a quadratic effect for the yellowness of the leg, with high value for 5.0% of GB. The ether extract content of shoulder showed decreased linear effect. The use of 7.5% of CG, in dry matter, can be recommend to replace corn of feedlot diets, without changing carcass traits and meat quality.

RESUMO Objetivou-se avaliar o efeito da inclusão de glicerina bruta (GB) em substituição ao milho, na dieta de cordeiros Pantaneiros confinados, sobre as características da carcaça e qualidade da paleta e do pernil. Foram utilizados 24 cordeiros machos, não castrados, em delineamento inteiramente casualizado, com quatro tratamentos (0, 2,5, 5,0 e 7,5% de GB em base da MS). Não houve efeito da inclusão de GB sobre os não componentes de carcaça. Houve efeito quadrático para peso de carcaça quente, com menor valor para 2,5% de GB. A composição regional e tecidual da carcaça não foi alterada pela substituição do milho pela GB. A composição tecidual da paleta e pernil e as características instrumentais da paleta não foram afetadas pelos teores de GB. Houve efeito quadrático para a intensidade de amarelo do pernil, com maior valor para 5,0% de GB. O teor de extrato etéreo da paleta apresentou efeito linear decrescente. Pode-se recomendar a utilização de 7,5% de GB, na matéria seca, em substituição ao milho, sem alteração das características da carcaça e qualidade da carne.

RESUMEN

SUMMARY The objective was to assess the effect of inclusion of crude glycerin (CG) replacing corn in the diet of feedlot Pantaneiro lambs on the non-carcass components, regional and tissue composition, and carcass traits. Were used 24 not castrated males, in a completely randomized design with four treatments (0, 2.5, 5.0 and 7.5% of CG on DM basis). There was no effect of GB inclusion on non-carcass components. There was a quadratic effect for hot carcass weight, with lower value to 2.5% of CG. Regional and tissue composition of the carcass was not affected by the substitution of corn by CG. The tissue composition of shoulder and leg and instrumental traits of the shoulder were not affected by CG. There was a quadratic effect for the yellowness of the leg, with high value for 5.0% of GB. The ether extract content of shoulder showed decreased linear effect. The use of 7.5% of CG, in dry matter, can be recommend to replace corn of feedlot diets, without changing carcass traits and meat quality.

RESUMO Objetivou-se avaliar o efeito da inclusão de glicerina bruta (GB) em substituição ao milho, na dieta de cordeiros Pantaneiros confinados, sobre as características da carcaça e qualidade da paleta e do pernil. Foram utilizados 24 cordeiros machos, não castrados, em delineamento inteiramente casualizado, com quatro tratamentos (0, 2,5, 5,0 e 7,5% de GB em base da MS). Não houve efeito da inclusão de GB sobre os não componentes de carcaça. Houve efeito quadrático para peso de carcaça quente, com menor valor para 2,5% de GB. A composição regional e tecidual da carcaça não foi alterada pela substituição do milho pela GB. A composição tecidual da paleta e pernil e as características instrumentais da paleta não foram afetadas pelos teores de GB. Houve efeito quadrático para a intensidade de amarelo do pernil, com maior valor para 5,0% de GB. O teor de extrato etéreo da paleta apresentou efeito linear decrescente. Pode-se recomendar a utilização de 7,5% de GB, na matéria seca, em substituição ao milho, sem alteração das características da carcaça e qualidade da carne.

RESUMEN

SUMMARY Objective to evaluate the effect of the inclusion of levels of crude Glycerin in the feeding of lambs in the biometric characteristics and testicular histological. 24 lambs were neutered, not confined with 93.79 ± 5.73 days of age and body weight of 20.22 ± 2.84 kg. The treatments tested were: 0; 2.5; 5.0 and 7.5% of crude Glycerin injection in dry matter of diet in place of maize. The animals were slaughtered using the criteria in body condition score of 2.5 to 3.5 on a scale ranging from 1 to 5, and the variables evaluated were the initial weight, final weight, hot carcass weight, fat cover thickness, body condition, and the biometric parameters: testicular weight, scrotal perimeter in the scrotum, testicle weight left and right volume of right and left testicle, testicular testicular length width, seminiferous tubule diameter and height of germinal epithelium. There was no significant influence of crude Glycerin levels on any of the variables analyzed, also there was no correlation between the features assessed with body condition. Positive correlations were observed between hot carcass weight and fat thickness (r=0,57, p= p 0,05)). There was positive correlation (r=0,55, p= p 0,05)) between scrotal perimeter and body weight. The tubule diameter (r=0,47, p=p 0,05) and height of the seminiferous epithelium (r=0,62, p=p 0,05) were correlated with testicular volume. The inclusion of increasing levels of crude Glycerin in the feeding of lambs Pantaneiros, did not influence the biometric characteristics and testicular histométrics of animals.

RESUMO Objetivou-se avaliar o efeito da inclusão de níveis de glicerina bruta na alimentação de cordeiros nas características biométricas e histológicas testiculares. Foram utilizados 24 cordeiros não castrados, confinados com 93,79 ± 5,73 dias de idade e peso corporal de 20,22±2,84kg. Os tratamentos testados foram: 0; 2,5; 5,0 e 7,5% de inclusão de glicerina bruta na matéria seca da dieta em substituição ao milho. Os animais foram abatidos usando a condição corporal como critério em escore de 2,5 a 3,5, em uma escala que varia de 1 a 5, sendo que as variáveis avaliadas foram o peso inicial, peso final, peso de carcaça quente, espessura de gordura de cobertura, condição corporal, e os parâmetros biométricos testiculares: perímetro escrotal, peso testicular no escroto, peso dos testículos direito e esquerdo, volume dos testículos direito e esquerdo, largura testicular, comprimento testicular, diâmetro de túbulo seminífero e altura de epitélio germinativo. Não houve influência significativa dos níveis de glicerina bruta sobre nenhuma das variáveis analisadas, também não houve correlação entre as características avaliadas com a condição corporal. Foram observadas correlações positivas entre o peso de carcaça quente e espessura de gordura de cobertura (r=0,57, p 0,05). Houve correlação positiva (r=0,55, p 0,05)) entre perímetro escrotal e peso corporal. O diâmetro do túbulo (r=0,47, p 0,05) e a altura do epitélio seminíferos (r=0,62, p 0,05) estiveram correlacionados com o volume testicular. A inclusão de níveis crescentes de glicerina bruta na alimentação de cordeiros Pantaneiros até 7,5% de inclusão não influencia nas características biométricas e histométricas testiculares dos animais.

RESUMEN

The objective was to evaluate the composition of carcass cuts and tissue of lambs shoulder and leg finished in feedlot receiving diets containing whole or disabled soybean grain with two concentrate levels (50% and 80% of DM). There were used 20 crossbreed entire male lambs, 120 days of age and initial body weight of 22.6 ± 2.06 kg. A completely randomized design was used, allocated in a factorial arrangement 2x2 (levels concentrate and processing of soybean grain). The slaughter criterion was body condition between 3 and 3.5. The weight of sirloin cut was superior with 80% of concentrate. In the shoulder tissue composition, the level of 50% concentrate increased the ratio of subcutaneous fat. In natura soybean provided higher values for weight and ratio of subcutaneous and total fat. For the leg tissue composition, the grain of disabled soybean showed higher muscle yield and muscle:bone ratio. Diets with 80% of concentrate, regardless of processing soybean grain, improved commercial yield and the diets containing disabled soybean more edible portion.

Objetivou-se avaliar a composição dos cortes da carcaça e tecidual da paleta e pernil de cordeiros terminados em confinamento, recebendo dietas contendo grão de soja in natura ou desativado com dois níveis de concentrado (50% e 80% da MS). Foram utilizados 20 cordeiros, machos não castrados, sem raça definida, com 120 dias de idade e peso corporal inicial de 22,6 ± 2,06 kg. O delineamento foi inteiramente ao acaso em esquema fatorial 2x2 (níveis de concentrado e processamento do grão de soja). O critério de abate foi determinado pela condição corporal entre 3 e 3,5. O peso do corte lombo foi superior para o nível de 80% de concentrado. Na composição tecidual da paleta, o nível de 50% de concentrado aumentou o rendimento de gordura subcutânea. O grão de soja in natura proporcionou maiores valores para peso e rendimento de gordura subcutânea e total. Para a composição tecidual do pernil, o grão de soja desativado proporcionou maior rendimento de músculo e para a relação músculo:osso. As dietas com 80% de concentrado, independentemente do processamento do grão de soja, proporcionaram melhor rendimento de cortes cárneos, e as dietas contendo grão de soja desativado maior porção comestível.

RESUMEN

The objective was to evaluate the composition of carcass cuts and tissue of lambs shoulder and leg finished in feedlot receiving diets containing whole or disabled soybean grain with two concentrate levels (50% and 80% of DM). There were used 20 crossbreed entire male lambs, 120 days of age and initial body weight of 22.6 ± 2.06 kg. A completely randomized design was used, allocated in a factorial arrangement 2x2 (levels concentrate and processing of soybean grain). The slaughter criterion was body condition between 3 and 3.5. The weight of sirloin cut was superior with 80% of concentrate. In the shoulder tissue composition, the level of 50% concentrate increased the ratio of subcutaneous fat. In natura soybean provided higher values for weight and ratio of subcutaneous and total fat. For the leg tissue composition, the grain of disabled soybean showed higher muscle yield and muscle:bone ratio. Diets with 80% of concentrate, regardless of processing soybean grain, improved commercial yield and the diets containing disabled soybean more edible portion.

Objetivou-se avaliar a composição dos cortes da carcaça e tecidual da paleta e pernil de cordeiros terminados em confinamento, recebendo dietas contendo grão de soja in natura ou desativado com dois níveis de concentrado (50% e 80% da MS). Foram utilizados 20 cordeiros, machos não castrados, sem raça definida, com 120 dias de idade e peso corporal inicial de 22,6 ± 2,06 kg. O delineamento foi inteiramente ao acaso em esquema fatorial 2x2 (níveis de concentrado e processamento do grão de soja). O critério de abate foi determinado pela condição corporal entre 3 e 3,5. O peso do corte lombo foi superior para o nível de 80% de concentrado. Na composição tecidual da paleta, o nível de 50% de concentrado aumentou o rendimento de gordura subcutânea. O grão de soja in natura proporcionou maiores valores para peso e rendimento de gordura subcutânea e total. Para a composição tecidual do pernil, o grão de soja desativado proporcionou maior rendimento de músculo e para a relação músculo:osso. As dietas com 80% de concentrado, independentemente do processamento do grão de soja, proporcionaram melhor rendimento de cortes cárneos, e as dietas contendo grão de soja desativado maior porção comestível.

RESUMEN

The objective of the present study was to estimate genetic parameters for test-day milk, fat and protein yields and 305-day-yields in Murrah buffaloes. 4,757 complete lactations of Murrah buffaloes were analyzed. Co-variance components were estimated by the restricted maximum likelihood method. The models included additive direct genetic and permanent environmental effects as random effects, and the fixed effects of contemporary group, milking number and age of the cow at calving as linear and quadratic covariables. Contemporary groups were defined by herd-year-month of test for test-day yields and by herd-year-season of calving for 305-day yields. The heritability estimates obtained by two-trait analysis ranged from 0.15 to 0.24 for milk, 0.16 to 0.23 for protein and 0.13 to 0.22 for fat, yields. Genetic and phenotypic correlations were all positive. The observed population additive genetic variation indicated that selection might be an effective tool in changing population means in milk, fat and protein yields.