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The aim of this study was to evaluate the effect of the polymorphic FecGE allele on reproductive traits in Santa Inês and Morada Nova ewes. The traits evaluated were as follows: total progeny weights at birth (PWB) and weaning (PWW) and progeny survival rates at birth (PSRB) and weaning (PSRW). A total of 389 animals, belonging to two Santa Inês herds and one Morada Nova herd, were genotyped. There was a difference between the averages for all the traits studied regarding type of parturition, herd/breed, genotype/herd, and genotype/type of parturition. For each additional progeny, if the female was FecGE/E, the PWB decreased by 1.02 kg and the PWW by 3.16 kg, also with a 0.04% reduction in PSRB and no change in PSRW. If the female was FecGE/+, the reduction in PWB was 0.24 kg, with an increase in PSRW by 0.11%, but no change in PWW and PSRB. In general, these results demonstrate that FecG+/+ females have a better ability to increase their number of progenies without reducing PWB and PWW (also similar to FecGE/+). Thus, it is suggested that further studies on the association between the traits of interest and candidate genes in sheep should be carried out so that the regions which have the greatest effect on the expression of these traits are actually identified. It was not possible to verify the effect of the FecGE allele on the PWB, PWW, PSRB, and PSRW in these Morada Nova and Santa Inês herds.

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The study's objective was to compare the genomic prediction ability methods for the traits milk yield, milk composition and somatic cell count of Saanen Brazilian goats. Nine hundred forty goats, genotyped with an Axiom_OviCap (Caprine) panel, Affimetrix customized array with 62,557 single nucleotide polymorphisms (SNPs), were used for the genomic selection analyses. The genomic methods studied to estimate the effects of SNPs and direct genomic values (DGV) were as follows: (a) genomic BLUP (GBLUP), (b) Bayes Cπ and (c) Bayesian Lasso (BLASSO). Estimated breeding values (EBV) and deregressed estimated breeding values (dEBV) were used as response variables for the genomic predictions. The prediction ability was assessed by Pearson's correlation between DGV and response variables (EBV and dEBV). Regression coefficients of the response variables on the DGV were obtained to verify if the genomic predictions were biased. In addition, the mean square error of prediction (MSE) was used as a measure of verification of model fit to the data. The means of prediction accuracy, when EBV was used as a response variable, were 0.68, 0.68 and 0.67 for GBLUP, Bayes Cπ and BLASSO, respectively. With dEBV, the mean prediction accuracy was 0.50 for all models. The averages of the EBV regression coefficients on DGV were 1.08 for all models (GBLUP, Bayes Cπ and BLASSO), higher than those obtained for the regression coefficient of dEBV on DGV, which presented values of 1.05, 1.05 and 1.08 for GBLUP, Bayes Cπ and BLASSO, respectively. None of the methods stood out in terms of prediction ability; however, the GBLUP method was the most appropriate for estimating the DGV, in a slightly more reliable and less biased way, besides presenting the lowest computational cost. In the context of the present study, EBV was the preferred response variables considering the genomic prediction accuracy despite dEBV also presented lower bias.

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This study aimed to estimate the genetic parameters for somatic cell count (SCC) and the genetic association between SCC and milk production traits using two different methods of SCC normalization. The dataset contained information on 8870 lactation records of 6172 Guzerá dairy cows selected for dual-purpose from 95 herds. The lactation means of SCC were normalized in two ways: (a) SCC1 = log10 (SCC) and (b) SCC2 = log2 (SCC/100) + 3. Multivariate analyses were performed considering milk production traits over the course of 305 days of lactation. Estimates of the variance components and genetic parameters were carried out by the Bayesian inference method, applying Gibbs sampling. Single chains of 2,000,000 iterations were used, with sampling discards of the first 5000 chains and a sampling period of every 50 iterations. The deviation of information criteria (DIC) was used to evaluate the best transformation for standardization of the SCC data, comparing analysis 1 (milk production traits over 305 days and SCC1) with analysis 2 (milk production traits over 305 days and SCC2). According to the data structure of this study, SCC1 normalization was the most efficient method and produced better estimates than normalization by the SCC2 method. The heritability estimates for SCC were low regardless of the transformation method used, indicating a small possibility of expressive genetic gains from the direct selection of these traits. However, the repeatability indicated the potential for increasing heritability estimates if the effects of the permanent environment were reduced. The genetic correlations between the milk yield and SCC traits do not indicate the possibility of a correlated genetic gain from the direct selection of one trait. However, concomitant selection for milk production traits and SCC will likely not affect the individual response either.

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The aim of this study was to evaluate the effects of different concentrations of BMP4 on activation, development and mRNA expression of GDF9, BMP15, PCNA, Bax and Bcl2 in cultured bovine follicles enclosed in ovarian tissues. Ovarian tissue fragments were cultured for 6 days in α-MEM+ alone or supplemented with different concentrations of BMP4 (10, 50 or 100 ng/ml). Classical histology was performed to analyze follicle growth and morphology, while real-time PCR was used to analyze mRNA levels in fresh and cultured tissues. After 6 days, the culture of ovarian tissue in α-MEM+ alone or supplemented with 10, 50 or 100 ng/ml BMP4 promoted follicular activation. The different concentrations of BMP4 maintained the percentage of normal follicles similar to results of the control. The presence of 100 ng/ml BMP-4 in culture medium increased oocyte and follicular diameters of primary and secondary follicles when compared with those follicles from uncultured control or cultured in α-MEM+ alone (P < 0.05). The tissues cultured in the presence of increasing concentrations of BMP4 had an increase in mRNA expression of the tested genes, but despite this the differences were not statistically significant. In conclusion, 100 ng/ml BMP4 promotes an increase in diameters of follicles and oocytes of primary and secondary follicles after 6 days of in vitro culture.

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Objetivou-se quantificar a produção e a composição química do leite das ovelhas Rabo Largo, mantidas sob dois sistemas de alimentação durante a fase lactacional. Foram utilizadas 60 ovelhas, primíparas e multíparas entre um e quatro anos de idade, amamentando um ou dois cordeiros, mantidas sob dois sistemas de alimentação, com peso vivo médio inicial de 43 kg e 40,5 kg para o lote suplementado e lote não suplementado, respectivamente. Foi medida a produção de leite semanalmente, através do método indireto da dupla pesagem, após o período do colostro. Foram coletadas também amostras do leite, a cada semana, para a determinação da composição química. Os dados de produção de leite foram analisados como medidas repetidas no tempo e entre grupo de fatores. Os fatores considerados foram ano e períodos chuvoso e seco no início de lactação, ordem de lactação, interação tipo de parto e sexo das crias e entre os lotes. Para efeito de comparação de médias entre os lotes, utilizou-se o teste de média dos mínimos quadrados com nível de significância de 5%. Verificou-se que o lote suplementado obteve maior produção de leite do que o lote não suplementado, exceto nas duas últimas semanas de lactação. O pico de produção ocorreu durante a segunda semana de lactação para ambos os lotes. As ovelhas da raça Rabo Largo sem acesso a suplementação responderam de maneira positiva expressando adaptabilidade as condições semiáridas com potencial leiteiro semelhante a outras raças ovinas, e quando suplementadas obtém-se maior produção e manutenção dos mais elevados níveis dos componentes químicos do leite na última semana de lactação.

The aim of this study was to quantify the production and the chemical composition of the milk of ewes of Rabo Largo breed raised under two feeding systems during the lactation. Sixty ewes, primiparous and multiparous, aged one to four, years nursing one or two lambs were raised under two feeding systems, with average body weight of 43 kg and 40.5 kg for the groups supplemented and not supplemented, respectively. The milk yield were measured weekly, using the indirect method of double weighing, after a period of colostrum. Milk samples were also collected every week for determination of the chemical composition. The data of daily milk production were analyzed with repeated measures over time and across groups of factors. The subject factors considered were year and rainy and dry periods in early lactation, lactation order, interaction between type of lambing and sex of the offspring and between the batches. For comparison of means between batches, we used the average of the least squares with a significance level of 5%. It was found that the supplemented group presented a higher milk yield than the not supplemented group, except to the two last weeks old lactation. Already peak production occurred during the second week of lactation for both lots. The dietary supplementation increases the production and maintained the highest levels of the chemical components of milk in the last week of lactation.

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Objetivou-se quantificar a produção e a composição química do leite das ovelhas Rabo Largo, mantidas sob dois sistemas de alimentação durante a fase lactacional. Foram utilizadas 60 ovelhas, primíparas e multíparas entre um e quatro anos de idade, amamentando um ou dois cordeiros, mantidas sob dois sistemas de alimentação, com peso vivo médio inicial de 43 kg e 40,5 kg para o lote suplementado e lote não suplementado, respectivamente. Foi medida a produção de leite semanalmente, através do método indireto da dupla pesagem, após o período do colostro. Foram coletadas também amostras do leite, a cada semana, para a determinação da composição química. Os dados de produção de leite foram analisados como medidas repetidas no tempo e entre grupo de fatores. Os fatores considerados foram ano e períodos chuvoso e seco no início de lactação, ordem de lactação, interação tipo de parto e sexo das crias e entre os lotes. Para efeito de comparação de médias entre os lotes, utilizou-se o teste de média dos mínimos quadrados com nível de significância de 5%. Verificou-se que o lote suplementado obteve maior produção de leite do que o lote não suplementado, exceto nas duas últimas semanas de lactação. O pico de produção ocorreu durante a segunda semana de lactação para ambos os lotes. As ovelhas da raça Rabo Largo sem acesso a suplementação responderam de maneira positiva expressando adaptabilidade as condições semiáridas com potencial leiteiro semelhante a outras raças ovinas, e quando suplementadas obtém-se maior produção e manutenção dos mais elevados níveis dos componentes químicos do leite na última semana de lactação.(AU)

The aim of this study was to quantify the production and the chemical composition of the milk of ewes of Rabo Largo breed raised under two feeding systems during the lactation. Sixty ewes, primiparous and multiparous, aged one to four, years nursing one or two lambs were raised under two feeding systems, with average body weight of 43 kg and 40.5 kg for the groups supplemented and not supplemented, respectively. The milk yield were measured weekly, using the indirect method of double weighing, after a period of colostrum. Milk samples were also collected every week for determination of the chemical composition. The data of daily milk production were analyzed with repeated measures over time and across groups of factors. The subject factors considered were year and rainy and dry periods in early lactation, lactation order, interaction between type of lambing and sex of the offspring and between the batches. For comparison of means between batches, we used the average of the least squares with a significance level of 5%. It was found that the supplemented group presented a higher milk yield than the not supplemented group, except to the two last weeks old lactation. Already peak production occurred during the second week of lactation for both lots. The dietary supplementation increases the production and maintained the highest levels of the chemical components of milk in the last week of lactation.(AU)

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A multivariate approach was adopted to evaluate the relationship among traits measured in the performance testing of Morada Nova sheep, verify the efficiency of a ranking method used in these tests and identify the most significant traits for use in future analyses. Data from 150 young rams participating in five versions of the performance tests for the Morada Nova breed were used. Twenty traits were measured in each animal: initial weight (IW), final weight (FW), average daily weight gain (ADG), loin eye area (LEA), scrotal circumference (SC), fat thickness (FT), conformation (C), precocity (Pc), muscularity (M), breed features (BF), legs (L), withers height (WH), chest width (CW), rump height (RH), rump width (RW), rump length (RL), body length (BL), body depth (BD), heart girth (HG) and body condition scoring (BCS). The Pearsons correlation coefficients ranged from 0.10 to 0.93, with the highest correlations were between body weight variables and morphometric measurements. The three first principal components explained 72.28% of the total variability among all traits. The variables related to animal size defined the first principal component, whereas those related to visual appraisal and suitability for meat production defined the second and third principal components, respectively. The combination of traits from the principal component analysis showed that the ranking met...(AU)

Objetivou-se neste trabalho adotar uma abordagem multivariada para avaliar a relação entre as características medidas nos testes de desempenho de ovinos Morada Nova para verificar a eficácia do método de classificação utilizado nestes testes, e identificar as características mais importantes para serem usadas em análises futuras. Foram utilizados dados de 150 carneiros jovens participantes de cinco edições do teste de desempenho da raça Morada Nova. Vinte características foram mensuradas em cada animal: peso inicial (PI), peso final (PF), ganho de peso médio diário (GPMD), área de olho de lombo (AOL), perímetro escrotal (PE), espessura de gordura (EG), conformação (C), precocidade (Pc), musculosidade (M), tipo racial (TP), aprumos (A), altura de cernelha (AC), largura de peito (LP), altura da garupa (AG), largura da garupa (LG), comprimento da garupa (CG), comprimento corporal (CC), profundidade (P), perímetro torácico (PT) e escore de condição corporal (ECC). Os Coeficientes de correlação de Pearson variaram de 0,10 a 0,93, sendo que as maiores correlações foram entre as variáveis de peso corporal e medidas morfométricas. Os três primeiros componentes principais explicaram 72,28% da variabilidade total entre todas as variáveis. As variáveis relacionadas ao porte do animal obtiveram maiores ponderadores no primeiro componente principal, enquanto as características relacionada...(AU)

Assuntos

RESUMO

A multivariate approach was adopted to evaluate the relationship among traits measured in the performance testing of Morada Nova sheep, verify the efficiency of a ranking method used in these tests and identify the most significant traits for use in future analyses. Data from 150 young rams participating in five versions of the performance tests for the Morada Nova breed were used. Twenty traits were measured in each animal: initial weight (IW), final weight (FW), average daily weight gain (ADG), loin eye area (LEA), scrotal circumference (SC), fat thickness (FT), conformation (C), precocity (Pc), muscularity (M), breed features (BF), legs (L), withers height (WH), chest width (CW), rump height (RH), rump width (RW), rump length (RL), body length (BL), body depth (BD), heart girth (HG) and body condition scoring (BCS). The Pearsons correlation coefficients ranged from 0.10 to 0.93, with the highest correlations were between body weight variables and morphometric measurements. The three first principal components explained 72.28% of the total variability among all traits. The variables related to animal size defined the first principal component, whereas those related to visual appraisal and suitability for meat production defined the second and third principal components, respectively. The combination of traits from the principal component analysis showed that the ranking met...

Objetivou-se neste trabalho adotar uma abordagem multivariada para avaliar a relação entre as características medidas nos testes de desempenho de ovinos Morada Nova para verificar a eficácia do método de classificação utilizado nestes testes, e identificar as características mais importantes para serem usadas em análises futuras. Foram utilizados dados de 150 carneiros jovens participantes de cinco edições do teste de desempenho da raça Morada Nova. Vinte características foram mensuradas em cada animal: peso inicial (PI), peso final (PF), ganho de peso médio diário (GPMD), área de olho de lombo (AOL), perímetro escrotal (PE), espessura de gordura (EG), conformação (C), precocidade (Pc), musculosidade (M), tipo racial (TP), aprumos (A), altura de cernelha (AC), largura de peito (LP), altura da garupa (AG), largura da garupa (LG), comprimento da garupa (CG), comprimento corporal (CC), profundidade (P), perímetro torácico (PT) e escore de condição corporal (ECC). Os Coeficientes de correlação de Pearson variaram de 0,10 a 0,93, sendo que as maiores correlações foram entre as variáveis de peso corporal e medidas morfométricas. Os três primeiros componentes principais explicaram 72,28% da variabilidade total entre todas as variáveis. As variáveis relacionadas ao porte do animal obtiveram maiores ponderadores no primeiro componente principal, enquanto as características relacionada...

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O presente estudo teve como objetivo determinar a ocorrência da infecção por Cryptosporidium spp. em cabritos de Quixadá, Ceará, Brasil. Participaram do estudo 400 cabritos, com idade entre três e 360 dias, de ambos os sexos, com e sem padrão racial definido, procedentes de 25 estabelecimentos rurais distribuídos em três circuitos. As fezes foram cadastradas de acordo com o aspecto e cor, distribuídas em tubos tipo "eppendorf®" e congeladas in natura a -20°C, até o momento das extrações de DNA genômico do parasito com auxílio de kit comercial. Para amplificação de fragmentos da subunidade 18S do RNA ribossômico (rRNA) foi utilizada a "Nested"-PCR. A ocorrência de Cryptosporidium spp em cabritos de Quixadá foi de 7,50% (30/400). A frequência no período seco e no chuvoso foi de 9,55% (19/199) e 5,47% (11/201), respectivamente (χ²=2,39 e P>0,05). Amostras positivas foram identificadas em 64,00% (16/25) das propriedades estudadas e dessas amostras 50,00% (15/30) e 70,00% (21/30) tinham as fezes com aspecto e cor normais, respectivamente, sugerindo que cabritos assintomáticos estão eliminando oocistos. Não foi observada positividade para Cryptosporidium spp. em animais com 301 a 360 dias, demonstrando que animais mais velhos apresentam menos possibilidade de se infectarem com o parasito...

The present study aimed to determine the occurrence of infection by Cryptosporidium spp. in goat kids from Quixadá, Ceará, Brazil. The study included 400 goat kids of both sexes, 3 to 360 days old, with or without defined breed, originating from 25 farms distributed in three circuits. Feces were registered in accordance with the appearance and color, distributed into tubes Eppendorf tubes and frozen in natura at-20°C until the moment of extraction of genomic DNA from the parasite with the aid of a commercial kit. For amplification of fragments of the 18S subunit of ribosomal RNA (rRNA) was used to Nested PCR. The occurrence of Cryptosporidium spp. in goats kids of the Quixadá was 7.50% (30/400). The frequency in the dry period and rainy was 9.55% (19/199) and 5.47% (11/201) respectively (χ²=2.39 and P>0.05). Positive samples were identified in 64.00% (16/25) of the studied farms, and from these samples 50.00% (15/30) and 70.00% (21/30) had feces with normal appearance and color respectively, suggesting that the asymptomatic goats were eliminating oocysts. No positivity for Cryptosporidium spp. was observed in 301 to 360-day-old goats, demonstrating that older animals have less chance to become infected with the parasite...

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O presente estudo teve como objetivo determinar a ocorrência da infecção por Cryptosporidium spp. em cabritos de Quixadá, Ceará, Brasil. Participaram do estudo 400 cabritos, com idade entre três e 360 dias, de ambos os sexos, com e sem padrão racial definido, procedentes de 25 estabelecimentos rurais distribuídos em três circuitos. As fezes foram cadastradas de acordo com o aspecto e cor, distribuídas em tubos tipo "eppendorf®" e congeladas in natura a -20°C, até o momento das extrações de DNA genômico do parasito com auxílio de kit comercial. Para amplificação de fragmentos da subunidade 18S do RNA ribossômico (rRNA) foi utilizada a "Nested"-PCR. A ocorrência de Cryptosporidium spp em cabritos de Quixadá foi de 7,50% (30/400). A frequência no período seco e no chuvoso foi de 9,55% (19/199) e 5,47% (11/201), respectivamente (χ²=2,39 e P>0,05). Amostras positivas foram identificadas em 64,00% (16/25) das propriedades estudadas e dessas amostras 50,00% (15/30) e 70,00% (21/30) tinham as fezes com aspecto e cor normais, respectivamente, sugerindo que cabritos assintomáticos estão eliminando oocistos. Não foi observada positividade para Cryptosporidium spp. em animais com 301 a 360 dias, demonstrando que animais mais velhos apresentam menos possibilidade de se infectarem com o parasito.(AU)

The present study aimed to determine the occurrence of infection by Cryptosporidium spp. in goat kids from Quixadá, Ceará, Brazil. The study included 400 goat kids of both sexes, 3 to 360 days old, with or without defined breed, originating from 25 farms distributed in three circuits. Feces were registered in accordance with the appearance and color, distributed into tubes Eppendorf tubes and frozen in natura at-20°C until the moment of extraction of genomic DNA from the parasite with the aid of a commercial kit. For amplification of fragments of the 18S subunit of ribosomal RNA (rRNA) was used to Nested PCR. The occurrence of Cryptosporidium spp. in goats kids of the Quixadá was 7.50% (30/400). The frequency in the dry period and rainy was 9.55% (19/199) and 5.47% (11/201) respectively (χ²=2.39 and P>0.05). Positive samples were identified in 64.00% (16/25) of the studied farms, and from these samples 50.00% (15/30) and 70.00% (21/30) had feces with normal appearance and color respectively, suggesting that the asymptomatic goats were eliminating oocysts. No positivity for Cryptosporidium spp. was observed in 301 to 360-day-old goats, demonstrating that older animals have less chance to become infected with the parasite.(AU)

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Objetivou-se estimar parâmetros genéticos para características de crescimento em ovinos da raça Somalis Brasileira. Os dados utilizados neste estudo foram provenientes do rebanho da Embrapa Caprinos e Ovinos, localizado na cidade de Sobral - CE. Os dados continham registros de 1.120 animais no arquivo de pedigree. As características analisadas foram: peso ao nascer (PN), peso ao desmame (PD), ganho de peso do nascimento ao desmame (GND) e peso adulto (PA). As estimativas dos componentes de (co)variâncias e os parâmetros genéticos foram obtidos pelo método da Máxima Verossimilhança Restrita não Derivativa (DFREML), utilizando o programa MTDFREML. Nas análises unicaracterística, as herdabilidades foram de magnitude baixa a moderada. As magnitudes das herdabilidades maternas foram todas superiores às herdabilidades diretas. As herdabilidades das análises multicaracterísticas entre PN, PD e GND superaram as análises unicaracterísticas. As correlações genéticas apresentaram grande variação quanto aos seus valores.

The aim of this study was to estimate genetic parameters for growth traits in Somalis Brasileira hair sheep breed. The data used in this study were from the flock of Embrapa Caprinos and Ovinos, located in the city of Sobral - CE, Brazil. Data contained records of 1,120 animals in the pedigree file. The analyzed traits were birth weight (PN), weaning weight (PD), weight gain from birth to weaning (GND) and adult weight (PA). Estimates of (co)variances and genetic parameters were obtained by Derivative Free Restricted Maximum Likelihood Method (DFREML) using the MTDFREML software. The heritabilities were low to moderate in univariate analysis. The maternal heritabilities were higher than direct heritabilities. The heritabilities in multivariate analysis exceeded those in univariate analysis. The values of genetic correlations varied widely.

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Objetivou-se avaliar os efeitos da utilização da bagana de carnaúba (Copernicia prunifera (Mill.) H.E. Moore) (BC), como fonte de volumoso, sobre as características da carcaça de cordeiros terminados em confinamento. Foram utilizados 30 cordeiros mestiços Santa Inês x SRD desmamados, com peso corporal médio de 16,9 + 1,56 kg e idade média de 80 dias. Foram formuladas dietas com cinco níveis de substituição do feno de capim-tyfton 85 (Cynodon spp.) (FT) pela BC: 0%BC e 100%FT (testemunha); 25%BC e 75%FT; 50%BC e 50%FT; 75%BC e 25%FT; 100%BC e 0%FT. Os teores de umidade, proteína e cinzas da carne não foram influenciados pelas dietas. O peso ao abate, peso de carcaça quente, peso de carcaça fria e os rendimentos de carcaça quente e de carcaça fria diminuíram à medida que o FT era substituído pela BC. Os itens quebra ao resfriamento e perda ao jejum não foram influenciados pelas dietas. Os valores mais elevados para comprimentos de carcaça e de pernil, peso de pernil, peso de paleta e pesos de pernil, de paleta e de lombo foram observados no tratamento testemunha, enquanto os valores mais baixos foram observados no tratamento que recebeu apenas BC. Verificou-se o efeito das dietas sobre as porcentagens de tecido ósseo no pernil e na paleta e sobre as porcentagens de tecido ósseo, conectivo e adiposo do lombo. Conclui-se que a inclusão da bagana de carnaúba na dieta interfere negativamente no consumo e, consequentemente, nas características.

It were evaluated the effects of bagana of carnaúba (Copernicia prunifera (Mill.) H.E. Moore) (BC), as roughage source, on carcass characteristics of lambs finished in confinement. Thirty crossbred weaned lambs with 16.9 + 1.56 kg initial average weight and 80-day of age were used. Five diets with increasing levels of substitution of tifton 85 grass (Cynodon spp.) hay (FT) by BC were set: 0%BC and 100%FT; 25%BC and 75%FT; 50%BC and 50%FT; 75%BC and 25%FT; 100%BC and 0%FT. The levels of moisture, protein and ash of meat were not affected by diets. The highest slaughter weight, hot carcass weight, cold carcass weight and the yields of both hot carcass and cold carcass decreased as FT was replaced by BC. The chilling loss and fasting loss items were not affected by diets. The greatest values for lengths of carcass and ham, weight of ham, weight of shoulder and weight of loin were observed in control treatment, while the lower values were found in the treatment where the animals received only BC. It was observed effect of diets on percentages of bone tissues of ham and shoulder, and on percentages of bone, fat and connective tissue of the loin. It was concluded that the inclusion of bagana of carnauba in diet negatively interferes on intake and carcass quality of lambs in feedlot.

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RESUMO

Objetivou-se avaliar os efeitos da utilização da bagana de carnaúba (Copernicia prunifera (Mill.) H.E. Moore) (BC), como fonte de volumoso, sobre as características da carcaça de cordeiros terminados em confinamento. Foram utilizados 30 cordeiros mestiços Santa Inês x SRD desmamados, com peso corporal médio de 16,9 + 1,56 kg e idade média de 80 dias. Foram formuladas dietas com cinco níveis de substituição do feno de capim-tyfton 85 (Cynodon spp.) (FT) pela BC: 0%BC e 100%FT (testemunha); 25%BC e 75%FT; 50%BC e 50%FT; 75%BC e 25%FT; 100%BC e 0%FT. Os teores de umidade, proteína e cinzas da carne não foram influenciados pelas dietas. O peso ao abate, peso de carcaça quente, peso de carcaça fria e os rendimentos de carcaça quente e de carcaça fria diminuíram à medida que o FT era substituído pela BC. Os itens quebra ao resfriamento e perda ao jejum não foram influenciados pelas dietas. Os valores mais elevados para comprimentos de carcaça e de pernil, peso de pernil, peso de paleta e pesos de pernil, de paleta e de lombo foram observados no tratamento testemunha, enquanto os valores mais baixos foram observados no tratamento que recebeu apenas BC. Verificou-se o efeito das dietas sobre as porcentagens de tecido ósseo no pernil e na paleta e sobre as porcentagens de tecido ósseo, conectivo e adiposo do lombo. Conclui-se que a inclusão da bagana de carnaúba na dieta interfere negativamente no consumo e, consequentemente, nas características. (AU)

It were evaluated the effects of bagana of carnaúba (Copernicia prunifera (Mill.) H.E. Moore) (BC), as roughage source, on carcass characteristics of lambs finished in confinement. Thirty crossbred weaned lambs with 16.9 + 1.56 kg initial average weight and 80-day of age were used. Five diets with increasing levels of substitution of tifton 85 grass (Cynodon spp.) hay (FT) by BC were set: 0%BC and 100%FT; 25%BC and 75%FT; 50%BC and 50%FT; 75%BC and 25%FT; 100%BC and 0%FT. The levels of moisture, protein and ash of meat were not affected by diets. The highest slaughter weight, hot carcass weight, cold carcass weight and the yields of both hot carcass and cold carcass decreased as FT was replaced by BC. The chilling loss and fasting loss items were not affected by diets. The greatest values for lengths of carcass and ham, weight of ham, weight of shoulder and weight of loin were observed in control treatment, while the lower values were found in the treatment where the animals received only BC. It was observed effect of diets on percentages of bone tissues of ham and shoulder, and on percentages of bone, fat and connective tissue of the loin. It was concluded that the inclusion of bagana of carnauba in diet negatively interferes on intake and carcass quality of lambs in feedlot. (AU)

Assuntos

RESUMO

The genetic parameters for growth, reproductive and maternal traits in a multibreed meat sheep population were estimated by applying the Average Information Restricted Maximum Likelihood method to an animal model. Data from a flock supported by the Programa de Melhoramento Genético de Caprinos e Ovinos de Corte (GENECOC) were used. The traits studied included birth weight (BW), weaning weight (WW), slaughter weight (SW), yearling weight (YW), weight gain from birth to weaning (GBW), weight gain from weaning to slaughter (GWS), weight gain from weaning to yearling (GWY), age at first lambing (AFL), lambing interval (LI), gestation length (GL), lambing date (LD - number of days between the start of breeding season and lambing), litter weight at birth (LWB) and litter weight at weaning (LWW). The direct heritabilities were 0.35, 0.81, 0.65, 0.49, 0.20, 0.15 and 0.39 for BW, WW, SW, YW, GBW, GWS and GWY, respectively, and 0.04, 0.06, 0.10, 0.05, 0.15 and 0.11 for AFL, LI, GL, LD, LWB and LWW, respectively. Positive genetic correlations were observed among body weights. In contrast, there was a negative genetic correlation between GBW and GWS (-0.49) and GBW and GWY (-0.56). Positive genetic correlations were observed between AFL and LI, LI and GL, and LWB and LWW. These results indicate a strong maternal influence in this herd and the presence of sufficient genetic variation to allow mass selection for growth traits. Additive effects were of little importance for reproductive traits, and other strategies are necessary to improve the performance of these animals.

RESUMO

We determined the polymorphism C242T of the aromatase gene (Cyp19) and its allelic frequency, as well as the effect of the variants on productive and reproductive traits in 71 purebred Santa Inês sheep, 13 purebred Brazilian Somali sheep, nine purebred Poll Dorset sheep, and 18 crossbred 1/2 Dorper sheep. The animals were genotyped using the PCR-RFLP technique. The influence of the animal's genotype on its performance or on the performance of its lambs was analyzed by the least square method. Another factor assessed was the importance of the animal's genotype in analysis models for quantitative breeding value estimates, and whether there were differences among the averages of breeding values of animals with different genotypes for this gene. In the sample studied, no AA individuals were observed; the AB and BB frequencies were 0.64 and 0.36, respectively. All Brazilian Somali sheep were of genotype BB. All 1/2 Dorper BB animals presented a lower age at first lambing, and the Santa Inês BB ewes presented a lower lambing interval. In these same genetic groups, AB ewes presented higher litter weight at weaning. This is evidence that BB ewes have a better reproductive performance phenotype, whereas AB ewes present a better maternal ability phenotype. However, in general, animals with genotype AB presented better average breeding values than those with genotype BB.

RESUMO

We determined the polymorphism C242T of the aromatase gene (Cyp19) and its allelic frequency, as well as the effect of the variants on productive and reproductive traits in 71 purebred Santa Inês sheep, 13 purebred Brazilian Somali sheep, nine purebred Poll Dorset sheep, and 18 crossbred 1/2 Dorper sheep. The animals were genotyped using the PCR-RFLP technique. The influence of the animal's genotype on its performance or on the performance of its lambs was analyzed by the least square method. Another factor assessed was the importance of the animal's genotype in analysis models for quantitative breeding value estimates, and whether there were differences among the averages of breeding values of animals with different genotypes for this gene. In the sample studied, no AA individuals were observed; the AB and BB frequencies were 0.64 and 0.36, respectively. All Brazilian Somali sheep were of genotype BB. All 1/2 Dorper BB animals presented a lower age at first lambing, and the Santa Inês BB ewes presented a lower lambing interval. In these same genetic groups, AB ewes presented higher litter weight at weaning. This is evidence that BB ewes have a better reproductive performance phenotype, whereas AB ewes present a better maternal ability phenotype. However, in general, animals with genotype AB presented better average breeding values than those with genotype BB.

Assuntos

RESUMO

The genetic parameters for growth, reproductive and maternal traits in a multibreed meat sheep population were estimated by applying the Average Information Restricted Maximum Likelihood method to an animal model. Data from a flock supported by the Programa de Melhoramento Genético de Caprinos e Ovinos de Corte (GENECOC) were used. The traits studied included birth weight (BW), weaning weight (WW), slaughter weight (SW), yearling weight (YW), weight gain from birth to weaning (GBW), weight gain from weaning to slaughter (GWS), weight gain from weaning to yearling (GWY), age at first lambing (AFL), lambing interval (LI), gestation length (GL), lambing date (LD - number of days between the start of breeding season and lambing), litter weight at birth (LWB) and litter weight at weaning (LWW). The direct heritabilities were 0.35, 0.81, 0.65, 0.49, 0.20, 0.15 and 0.39 for BW, WW, SW, YW, GBW, GWS and GWY, respectively, and 0.04, 0.06, 0.10, 0.05, 0.15 and 0.11 for AFL, LI, GL, LD, LWB and LWW, respectively. Positive genetic correlations were observed among body weights. In contrast, there was a negative genetic correlation between GBW and GWS (-0.49) and GBW and GWY (-0.56). Positive genetic correlations were observed between AFL and LI, LI and GL, and LWB and LWW. These results indicate a strong maternal influence in this herd and the presence of sufficient genetic variation to allow mass selection for growth traits. Additive effects were of little importance for reproductive traits, and other strategies are necessary to improve the performance of these animals.

RESUMO

O objetivo deste trabalho foi estudar o efeito da covariância entre os efeitos direto e materno sobre as estimativas dos parâmetros genéticos e nas predições dos valores genéticos, direto e materno, para a característica dias para ganhar 160 kg (D160) na fase pré-desmama. Os parâmetros e as predições dos valores genéticos foram estimados utilizando o aplicativo MTDFREML. O modelo 1 incluiu os efeitos genéticos direto e materno e de ambiente permanente, além do efeito fixo de grupo contemporâneo e da covariável idade da vaca ao parto, assumindo a covariância entre o efeito direto e materno (sigmaam 0); o modelo 2, considerou os mesmos efeitos do modelo 1, mas a covariância entre os efeitos direto e materno foi considerada nula (sigmaam=0). As estimativas de correlação de classificação dos animais pelos valores genético foram realizadas utilizando a correlação de Spearman. As estimativas de herdabilidade direta e materna para D160 foram respectivamente, 0,12 ± 0,01 e 0,09 ± 0,02, sob o modelo 1, e 0,12 ± 0,01 e 0,07 ± 0,02, sob o modelo 2. A correlação genética entre os efeitos direto e materno foi de -0,14 ± 0,12 (modelo 1). A inclusão da covariância entre os efeitos direto e materno nos modelos de análises não alterou a estimativa dos parâmetros genéticos e a classificação dos animais pela ordem dos valores genéticos estimados, quando se considerou toda a população. Entretanto, verificou-se que à medida que diminui a proporção de animais selecionados diminui a correspondência entre a classificação dos animais obtida pelos dois modelos.

Assuntos

RESUMO

O objetivo deste trabalho foi estudar o efeito da covariância entre os efeitos direto e materno sobre as estimativas dos parâmetros genéticos e nas predições dos valores genéticos, direto e materno, para a característica dias para ganhar 160 kg (D160) na fase pré-desmama. Os parâmetros e as predições dos valores genéticos foram estimados utilizando o aplicativo MTDFREML. O modelo 1 incluiu os efeitos genéticos direto e materno e de ambiente permanente, além do efeito fixo de grupo contemporâneo e da covariável idade da vaca ao parto, assumindo a covariância entre o efeito direto e materno (sigmaam 0); o modelo 2, considerou os mesmos efeitos do modelo 1, mas a covariância entre os efeitos direto e materno foi considerada nula (sigmaam=0). As estimativas de correlação de classificação dos animais pelos valores genético foram realizadas utilizando a correlação de Spearman. As estimativas de herdabilidade direta e materna para D160 foram respectivamente, 0,12 ± 0,01 e 0,09 ± 0,02, sob o modelo 1, e 0,12 ± 0,01 e 0,07 ± 0,02, sob o modelo 2. A correlação genética entre os efeitos direto e materno foi de -0,14 ± 0,12 (modelo 1). A inclusão da covariância entre os efeitos direto e materno nos modelos de análises não alterou a estimativa dos parâmetros genéticos e a classificação dos animais pela ordem dos valores genéticos estimados, quando se considerou toda a população. Entretanto, verificou-se que à medida que diminui a proporção de animais selecionados diminui a correspondência entre a classificação dos animais obtida pelos dois modelos. (AU)

The aim of this work was to study the effect of the covariance between maternal and direct effects on estimatives of genetic parameters and on predictions of breeding values for days to gain 160 kg in the pre-weaning period (D160). The analysis were carried out using the MTDFREML software. The model 1 included the direct and maternal genetic effects and permanent environmental effect and the fixed effects of the contemporaneous group and the covariable age of dam at calving, assuming the covariance between maternal and direct effect (sam¹0); the model 2 included the same effects of model 1, but the covariance between maternal and direct effects was considered zero (sam=0). The rank correlations were obtained using Spearman correlation. The direct and maternal heritabilities for D160, were respectively, 0.12 ± 0.01 and 0.09 ± 0.02, for the model 1, and 0.12 ± 0.01 and 0.07 ± 0.02, for the model 2. The correlation between maternal and direct effects was -0.14 ± 0.12 (model 1). The inclusion of the covariance between maternal and direct effects in the analysis models had no influence on the genetic parameters and on the rank of the animals classified by breeding values, when all population was considered. However, as it reduced the proportion of selected animal was reduced there was a corresponding reduction on ranking animals through the two models. (AU)

Assuntos