Genetic variability of Guzerat cattle raised in northern Brazil, based on pedigree analysis / [Variabilidade genética do gado Guzerat criado no norte do Brasil, com base na análise do pedigree]

Genealogical data comprised 45,711 animals born between 1901 and 2016, with 48,127 animals in the pedigree file. Population structure was analyzed in terms of pedigree completeness, individual inbreeding coefficient (F), generation interval (L), rate of inbreeding (ΔF), effective population size (Ne), effective number of founders (ff), and effective number of ancestors (fa). The herd initially consisted of 13 bulls and 14 cows, and there were variations in the number of selected bulls and cows throughout the analyzed period, with 2,575 bulls, 13,691 cows, and 45,711 births recorded at the end of 2016. In total, 48.81% of the cows had only one progeny. Most dams (47.59%) were between three and seven years old, with a mean L in the population of 7.9 years. According to the results, 52.75% of the cows, 44.92% of the bulls, and 63.71% of the calves of the Guzerat breed in the northern region of Brazil showed some degree of inbreeding, with small-magnitude coefficients (0.56, 0.83, and 0.71% for cows, bulls, and calves, respectively). This fluctuation did not hinder the genetic evolution of the herd in the region. The effective population size does not seem to compromise the maintenance of genetic variability in the breed.

Os dados genealógicos compreenderam 45.711 animais nascidos entre 1901 e 2016, com 48.127 animais no arquivo de pedigree. A estrutura populacional foi analisada em termos de completude de pedigree, coeficiente de endogamia individual (F), intervalo de geração (L), taxa de endogamia (ΔF), tamanho efetivo da população (Ne), número efetivo de fundadores (ff) e número efetivo de ancestrais (fa). O rebanho consistia inicialmente de 13 touros e 14 vacas, e houve variações no número de touros e vacas selecionados ao longo do período analisado, com 2.575 touros, 13.691 vacas e 45.711 nascimentos registrados no final de 2016. No total, 48,81% das vacas tiveram apenas uma progênie. A maioria das barragens (47,59%) tinha entre três e sete anos, com média de L na população de 7,9 anos. De acordo com os resultados, 52,75% das vacas, 44,92% dos touros e 63,71% dos bezerros da raça Guzerá na região Norte do Brasil apresentaram algum grau de endogamia, com coeficientes de pequena magnitude (0,56, 0,83 e 0,71% para vacas, touros e bezerros, respectivamente). Essa flutuação não impediu a evolução genética do rebanho na região. O tamanho efetivo da população não parece comprometer a manutenção da variabilidade genética na raça.

Transplantation of amniotic membrane-derived multipotent cells ameliorates and delays the progression of chronic kidney disease in cats.

Chronic kidney disease (CKD) is a common clinical condition in domestic cats, characterized by tubulointerstitial, vascular and glomerular inflammation and severe fibrosis. Studies in rodent model of induced CKD have shown a decrease and stabilization of the clinical condition. In this study was evaluated the safety and effect of intrarenal and intravenous infusion of allogeneic mesenchymal stem cells (AMSCs) derived from feline amniotic membrane in cats with naturally occurring CKD. Cat AMSCs were harvested after mechanical and enzymatic digestion of amnion. A healthy cat received intrarenal injection of AMSCs guided by ultrasound in both kidneys (5 × 105  cells/kidney). Nine cats with CDK received repeated intravenous infusions of AMSCs (2 × 106 cells × 2 treatments). The clinical parameters of healthy cat did not change, but sedation and general anaesthesia was required. The number of interventions stressed the animal, and he developed transient haematuria after AMSC injection. Cats with CDK registered a significant improvement of renal function (decrease in serum creatinine and urine protein concentrations and increase in urine specific gravity). The kidney architecture and morphology did not change following the treatment. The feline AMSCs have a renoprotective effect and improve renal function in cats with naturally occurring CKD, stabilizing the clinical condition and disease progression. Thus, intravenous injection of AMSCs may be an important tool to provide welfare in cats with chronic kidney disease.

Exigência de lisina digestível para poedeiras semipesadas de 50 a 66 semanas de idade / Digestible lysine requirement for laying hens from 50 to 66 weeks of age

Com o objetivo de determinar a exigência de lisina digestível para poedeiras semipesadas no período de 50 a 66 semanas de idade, foi realizado experimento utilizando-se 150 poedeiras Shaver Brown, distribuídas em delineamento inteiramente ao acaso, com cinco tratamentos (níveis de lisina digestível: 0,79; 0,82; 0,85; 0,88 e 0,91%), seis repetições e cinco aves por unidade experimental. Foram avaliados a produção de ovos, peso médio e a massa de ovos, consumo de ração e de lisina, conversão alimentar por massa e por dúzia de ovos, gravidade específica, unidade Haugh, o índice de gema e albúmen, porcentagem de albúmen, gema e casca. O consumo de ração, a conversão alimentar por massa e dúzia de ovos, a produção, o peso e a massa de ovos não foram influenciados (P>0,05) pelos níveis de lisina digestível. Houve aumento linear no consumo de lisina (P<0,01) com o incremento dos níveis desse aminoácido nas rações. As porcentagens de albúmen, gema e casca não foram influenciadas (P>0,05) pelos níveis de lisina digestível estudados. Os níveis de lisina influenciaram de forma quadrática (P>0,05) a unidade Haugh e o índice de albúmen, sendo estimados os níveis de 0,884 e 0,868% de lisina digestível, respectivamente. Para o índice de gema, a associação do modelo quadrático ao Linear Response Plateau (LRP) estimou o nível de 0,903% de lisina digestível. Quando o objetivo é maximizar a qualidade interna dos ovos, recomenda-se o nível dietético de 0,884%, 0,868% e 0,903% de lisina digestível para unidade Haugh, índice de albúmen e índice de gema, respectivamente(AU)

With the objective of determining the requirement of digestible lysine for brown-egg laying hens in the period from 50 to 66 weeks of age, an experiment was carried out using 150 Shaver Brown laying hens, distributed in a completely randomized design, with five treatments (digestible lysine levels: 0.79, 0.82, 0.85, 0.88 and 0.91%), six replications and five birds per experimental unit. The production of eggs, weight and the egg mass, feed intake and lysine, feed mass and dozen eggs, specific gravity, Haugh unit, yolk and albumen index, percentage of albumen, yolk and bark were analyzed. Feed intake, feed conversion per dozen of eggs s and per egg mass, egg production, egg weight and egg mass were not influenced (P>0.05) by digestible lysine levels. There was a linear increase in lysine intake (P<0.01) with increasing levels of this amino acid in the diets. The albumen, yolk and shell percentages were not influenced (P>0.05) by studied digestible lysine levels. Lysine levels had a quadratic effect (P>0.05) Haugh unit and albumen index being estimated as 0.884 and 0.868% digestible lysine levels, respectively. For yolk index, the association of the quadratic model to Linear Response Plateau (LRP) estimated the level of 0.903% digestible lysine. When the aim is to maximize the internal egg quality, a dietary level of 0.884%, 0.868% and 0.903% digestible lysine for Haugh unit, albumen index and yolk index, respectively is recommended(AU)

Exigência de lisina digestível para poedeiras semipesadas de 50 a 66 semanas de idade / Digestible lysine requirement for laying hens from 50 to 66 weeks of age

Com o objetivo de determinar a exigência de lisina digestível para poedeiras semipesadas no período de 50 a 66 semanas de idade, foi realizado experimento utilizando-se 150 poedeiras Shaver Brown, distribuídas em delineamento inteiramente ao acaso, com cinco tratamentos (níveis de lisina digestível: 0,79; 0,82; 0,85; 0,88 e 0,91%), seis repetições e cinco aves por unidade experimental. Foram avaliados a produção de ovos, peso médio e a massa de ovos, consumo de ração e de lisina, conversão alimentar por massa e por dúzia de ovos, gravidade específica, unidade Haugh, o índice de gema e albúmen, porcentagem de albúmen, gema e casca. O consumo de ração, a conversão alimentar por massa e dúzia de ovos, a produção, o peso e a massa de ovos não foram influenciados (P>0,05) pelos níveis de lisina digestível. Houve aumento linear no consumo de lisina (P<0,01) com o incremento dos níveis desse aminoácido nas rações. As porcentagens de albúmen, gema e casca não foram influenciadas (P>0,05) pelos níveis de lisina digestível estudados. Os níveis de lisina influenciaram de forma quadrática (P>0,05) a unidade Haugh e o índice de albúmen, sendo estimados os níveis de 0,884 e 0,868% de lisina digestível, respectivamente. Para o índice de gema, a associação do modelo quadrático ao Linear Response Plateau (LRP) estimou o nível de 0,903% de lisina digestível. Quando o objetivo é maximizar a qualidade interna dos ovos, recomenda-se o nível dietético de 0,884%, 0,868% e 0,903% de lisina digestível para unidade Haugh, índice de albúmen e índice de gema, respectivamente.

With the objective of determining the requirement of digestible lysine for brown-egg laying hens in the period from 50 to 66 weeks of age, an experiment was carried out using 150 Shaver Brown laying hens, distributed in a completely randomized design, with five treatments (digestible lysine levels: 0.79, 0.82, 0.85, 0.88 and 0.91%), six replications and five birds per experimental unit. The production of eggs, weight and the egg mass, feed intake and lysine, feed mass and dozen eggs, specific gravity, Haugh unit, yolk and albumen index, percentage of albumen, yolk and bark were analyzed. Feed intake, feed conversion per dozen of eggs s and per egg mass, egg production, egg weight and egg mass were not influenced (P>0.05) by digestible lysine levels. There was a linear increase in lysine intake (P<0.01) with increasing levels of this amino acid in the diets. The albumen, yolk and shell percentages were not influenced (P>0.05) by studied digestible lysine levels. Lysine levels had a quadratic effect (P>0.05) Haugh unit and albumen index being estimated as 0.884 and 0.868% digestible lysine levels, respectively. For yolk index, the association of the quadratic model to Linear Response Plateau (LRP) estimated the level of 0.903% digestible lysine. When the aim is to maximize the internal egg quality, a dietary level of 0.884%, 0.868% and 0.903% digestible lysine for Haugh unit, albumen index and yolk index, respectively is recommended.

Inclusão da epistasia em modelo de avaliação genética de bovinos de corte compostos / The effect of the inclusion of epistasis on the genetic evaluation model of beef cattle composite

Dados de bovinos compostos foram analisados para avaliar o efeito da epistasia nos modelos de avaliação genética. As características analisadas foram os pesos aos 205 (P205) e 390 dias (P390) e perímetro escrotal aos 390 dias (PE390). As análises foram realizadas pela metodologia de máxima verossimilhança considerando-se dois modelos: o modelo 1 incluiu como covariáveis os efeitos aditivos diretos e maternos, e os não aditivos das heterozigoses para os efeitos diretos e para o materno total, e o modelo 2 considerou também o efeito direto de epistasia. Para comparação dos modelos, foram utilizados o critério de informação de Akaike (AIC) e o critério de informação Bayesiano de Schwartz (BIC), e o teste de razão de verossimilhança. A inclusão da epistasia no modelo de avaliação genética pouco alterou as estimativas de componentes de (co)variâncias genéticas aditivas e, consequentemente, as herdabilidades. O teste de verossimilhança e o critério de Akaike sugeriram que o modelo 2, que inclui a epistasia, apresentou maior aderência aos dados para todas as características analisadas. O critério BIC indicou este modelo como o melhor apenas para P205. Para análise genética dessa população, o modelo que considerou o efeito de epistasia foi o mais adequado.(AU)

Composite bovine data was analyzed with the objective of evaluating the effect of the epistasis parameter in the models of genetic evaluation. The analyzed characteristics were weight at 205 (W205) and 390 days (P390), and scrotal circumference at 390 days (SC390). The analysis were done by the maximum likelihood method, considering two models: model 1, which included as covariates the direct and maternal additive effects, and non-additive of the heterozygosis for the direct and total maternal, and model 2, which also considered the direct epistasis direct. The Akaike Information Criteria (AIC) and the Bayesiano of Schwartz Information Criteria (BIC) were used for the comparison of the models and the test of ratio of likelihood. The inclusion of the epistasis effects on the model of the genetic evaluation did not alter much the estimation of the genetic additive (co)variances components and, consequently the heritability. However, it was significantly superior by the likelihood ratio test for the studied characteristics. Through the BIC, model 2 was more adequate only for W205. For the genetic analysis of that population the model that considers the epitasis is the more adequate.(AU)

Inclusão da epistasia em modelo de avaliação genética de bovinos de corte compostos / The effect of the inclusion of epistasis on the genetic evaluation model of beef cattle composite

Dados de bovinos compostos foram analisados para avaliar o efeito da epistasia nos modelos de avaliação genética. As características analisadas foram os pesos aos 205 (P205) e 390 dias (P390) e perímetro escrotal aos 390 dias (PE390). As análises foram realizadas pela metodologia de máxima verossimilhança considerando-se dois modelos: o modelo 1 incluiu como covariáveis os efeitos aditivos diretos e maternos, e os não aditivos das heterozigoses para os efeitos diretos e para o materno total, e o modelo 2 considerou também o efeito direto de epistasia. Para comparação dos modelos, foram utilizados o critério de informação de Akaike (AIC) e o critério de informação Bayesiano de Schwartz (BIC), e o teste de razão de verossimilhança. A inclusão da epistasia no modelo de avaliação genética pouco alterou as estimativas de componentes de (co)variâncias genéticas aditivas e, consequentemente, as herdabilidades. O teste de verossimilhança e o critério de Akaike sugeriram que o modelo 2, que inclui a epistasia, apresentou maior aderência aos dados para todas as características analisadas. O critério BIC indicou este modelo como o melhor apenas para P205. Para análise genética dessa população, o modelo que considerou o efeito de epistasia foi o mais adequado.

Composite bovine data was analyzed with the objective of evaluating the effect of the epistasis parameter in the models of genetic evaluation. The analyzed characteristics were weight at 205 (W205) and 390 days (P390), and scrotal circumference at 390 days (SC390). The analysis were done by the maximum likelihood method, considering two models: model 1, which included as covariates the direct and maternal additive effects, and non-additive of the heterozygosis for the direct and total maternal, and model 2, which also considered the direct epistasis direct. The Akaike Information Criteria (AIC) and the Bayesiano of Schwartz Information Criteria (BIC) were used for the comparison of the models and the test of ratio of likelihood. The inclusion of the epistasis effects on the model of the genetic evaluation did not alter much the estimation of the genetic additive (co)variances components and, consequently the heritability. However, it was significantly superior by the likelihood ratio test for the studied characteristics. Through the BIC, model 2 was more adequate only for W205. For the genetic analysis of that population the model that considers the epitasis is the more adequate.

Non-additive genetic effects on weights and performance of a Brazilian Bos taurus x Bos indicus beef composite.

The aim of the present study was to evaluate the heterosis effects on weaning weight at 205 days (WW, n = 146,464), yearling weight at 390 days (YW, n = 69,315) and weight gain from weaning to yearling (WG, n = 59,307) in composite beef cattle. The fixed models were: RM, which included contemporary groups, class of age of dam, outcrossing percentages for direct and maternal effects, and additive direct and maternal (AM) breed effects; R, RM model, minus AM breed effects, and H, RM model, minus additive breed effects. The estimates for W205 were in general positive (P < 0.01). The R and H models resulted in similar estimates, but they were very different from the ones estimated by the RM model. For W390, the R and H models resulted in general positive estimates (P < 0.05). For WG, the RM model resulted in general significant heterosis effects (P < 0.05). It can be concluded that the RM model seems to supply estimates of better quality (P < 0.01).

Ajustamento para heterogeneidade de variâncias para produção de leite e gordura entre rebanhos da raça Pardo-Suíça no Brasil / Adjustment for heterogeneity of variance for milk and fat yield among herds of Brown Swiss in Brazil

Para verificar o efeito da inclusão das interações reprodutor x rebanho e reprodutor x rebanho-ano como fator de ajustamento da heterogeneidade de variância, registros de produção de leite e gordura foram estratificados, com base no desvio-padrão fenotípico da produção de leite ajustada, em duas classes: baixo (<1.280kg) e alto (>1.280kg) desvio-padrão. Três modelos foram utilizados, sem e com interação reprodutor x rebanho e reprodutor x rebanho-ano, em análises de característica única, geral e em cada classe de desvio-padrão. Médias e componentes de variâncias foram maiores na classe de alto desvio-padrão. Na classe de baixo desvio-padrão, a herdabilidade não se alterou com a inclusão dos efeitos de interação no modelo, sendo de 0,34 para produção de leite e de 0,32 para produção de gordura. Na classe de alto desvio-padrão, as herdabilidades foram: 0,37, 0,35 e 0,36, e de 0,35, 0,32 e 0,35, para produção de leite e gordura, nos modelos sem, com interação reprodutor x rebanho e com interação reprodutor x rebanho-ano, respectivamente. A inclusão do efeito de interação reprodutor x rebanho nos modelos foi significativa (P<0,01) para produção de gordura, em análise geral e na classe de alto desvio-padrão, pelo teste da razão de verossimilhança.(AU)

In order to verify the effect of including the interactions of sire x herd and the sire x herd-year, as a adjust factor of the variance heterogeneity, registers of milk and fat yields were classified into two classes of standard deviation: low (<1.280kg) and high (>1.280kg), based on phenotypic standard deviation of the milk production adjusted. Three models, without and with interaction of sire x herd and sire x herd-year, were used in the general univariate analyses and in each standard deviation class. Averages and variance components were higher in the high standard deviation. In the class of low standard deviation, heritability didn't alter with the inclusion of the interaction effects in the model, being of 0.34 for milk yield and 0.32 for fat yield. In the class of high standard deviation, heritabilities were: 0.37, 0.35 and 0.36, and of 0.35, 0.32 and 0.35, for milk and fat yield, in the models without and with interaction of sire x herd and with interaction of sire x herd-year, respectively. The inclusion of the interaction of sire x herd was significant (P<0.01) for fat yield, in general analyses and in the high standard deviation class, in the likelihood ratio test.(AU)

Ajustamento para heterogeneidade de variâncias para produção de leite e gordura entre rebanhos da raça Pardo-Suíça no Brasil / Adjustment for heterogeneity of variance for milk and fat yield among herds of Brown Swiss in Brazil

Para verificar o efeito da inclusão das interações reprodutor x rebanho e reprodutor x rebanho-ano como fator de ajustamento da heterogeneidade de variância, registros de produção de leite e gordura foram estratificados, com base no desvio-padrão fenotípico da produção de leite ajustada, em duas classes: baixo (<1.280kg) e alto (>1.280kg) desvio-padrão. Três modelos foram utilizados, sem e com interação reprodutor x rebanho e reprodutor x rebanho-ano, em análises de característica única, geral e em cada classe de desvio-padrão. Médias e componentes de variâncias foram maiores na classe de alto desvio-padrão. Na classe de baixo desvio-padrão, a herdabilidade não se alterou com a inclusão dos efeitos de interação no modelo, sendo de 0,34 para produção de leite e de 0,32 para produção de gordura. Na classe de alto desvio-padrão, as herdabilidades foram: 0,37, 0,35 e 0,36, e de 0,35, 0,32 e 0,35, para produção de leite e gordura, nos modelos sem, com interação reprodutor x rebanho e com interação reprodutor x rebanho-ano, respectivamente. A inclusão do efeito de interação reprodutor x rebanho nos modelos foi significativa (P<0,01) para produção de gordura, em análise geral e na classe de alto desvio-padrão, pelo teste da razão de verossimilhança.

In order to verify the effect of including the interactions of sire x herd and the sire x herd-year, as a adjust factor of the variance heterogeneity, registers of milk and fat yields were classified into two classes of standard deviation: low (<1.280kg) and high (>1.280kg), based on phenotypic standard deviation of the milk production adjusted. Three models, without and with interaction of sire x herd and sire x herd-year, were used in the general univariate analyses and in each standard deviation class. Averages and variance components were higher in the high standard deviation. In the class of low standard deviation, heritability didn't alter with the inclusion of the interaction effects in the model, being of 0.34 for milk yield and 0.32 for fat yield. In the class of high standard deviation, heritabilities were: 0.37, 0.35 and 0.36, and of 0.35, 0.32 and 0.35, for milk and fat yield, in the models without and with interaction of sire x herd and with interaction of sire x herd-year, respectively. The inclusion of the interaction of sire x herd was significant (P<0.01) for fat yield, in general analyses and in the high standard deviation class, in the likelihood ratio test.

Genetic parameters for growth traits of a Brazilian Bos taurus x Bos indicus beef composite.

The genetic analysis of composite data is very complicated, mainly because it is necessary to adjust data to the effects of heterosis and breed complementarity, and because there is usually considerable confounding of these data with several other effects, such as contemporary group effects, breed composition of the animal and maternal breed composition, among others. Data on birth weight (n = 151,083), weaning weight adjusted to 205 days (n = 137,257), yearling weight adjusted to 390 days (n = 61,410), weight gain from weaning to yearling (n = 56,653), and scrotum circumference (n = 23,323) and muscle score (n = 54,770), both adjusted to 390 days, from Bos taurus x Bos indicus composite beef calves born from 1994 to 2003 were analyzed to estimate (co)variance components and genetic parameters of growth traits. The animals belonged to the Montana Tropical program. Estimation was made by three models that approach adjustment to heterozygosis in order to suggest the best model. The RM model included contemporary groups, class of age of dam, outcrossing percentages for direct and maternal effects, and direct and maternal additive genetic breed effects as covariates; the R model was the same as RM, but without additive maternal breed effects, and H was the same as RM, but not considering any additive breed effect. Both R2 values and consistency of genetic parameters indicate that the more complex model (RM), which considers maternal and individual additive genetic breed effect, produces the best estimates when compared to other models. The R model seems to overestimate (co)variance components. The magnitudes of direct and maternal heritability estimates, obtained in this study, would permit genetic improvement for weight and growth traits, as much by selection of direct genetic effects for weight and growth as for the improvement of maternal performance, but in different lineages. Therefore, the correlations between these effects were unfavorable.

Genetic parameters for growth traits of a Brazilian Bos taurus x Bos indicus beef composite

The genetic analysis of composite data is very complicated, mainly because it is necessary to adjust data to the effects of heterosis and breed complementarity, and because there is usually considerable confounding of these data with several other effects, such as contemporary group effects, breed composition of the animal and maternal breed composition, among others. Data on birth weight (n = 151,083), weaning weight adjusted to 205 days (n = 137,257), yearling weight adjusted to 390 days (n = 61,410), weight gain from weaning to yearling (n = 56,653), and scrotum circumference (n = 23,323) and muscle score (n = 54,770), both adjusted to 390 days, from Bos taurus x Bos indicus composite beef calves born from 1994 to 2003 were analyzed to estimate (co)variance components and genetic parameters of growth traits. The animals belonged to the Montana Tropical® program. Estimation was made by three models that approach adjustment to heterozygosis in order to suggest the best model. The RM model included contemporary groups, class of age of dam, outcrossing percentages for direct and maternal effects, and direct and maternal additive genetic breed effects as covariates; the R model was the same as RM, but without additive maternal breed effects, and H was the same as RM, but not considering any additive breed effect. Both R2 values and consistency of genetic parameters indicate that the more complex model (RM), which considers maternal and individual additive genetic breed effect, produces the best estimates when compared to other models. The R model seems to overestimate (co)variance components. The magnitudes of direct and maternal heritability estimates, obtained in this study, would permit genetic improvement for weight and growth traits, as much by selection of direct genetic effects for weight and growth as for the improvement of maternal performance, but in different lineages. Therefore, the correlations between these effects were unfavorable.

Avaliaçäo de frangos de corte utilizando técnicas de análise multivariada: I - Características de carcaça / Carcass traits multivariate analysis techniques in broilers evaluation

Foram utilizadas técnicas de análise multivariada para comparar dois híbridos obtidos de linhas de frango de corte desenvolvidas pela Universidade Federal de Viçosa com dois híbridos comerciais. As características avaliadas foram: peso ao abate (PAB), peso da carcaça (PC), peso do peito (PP), peso da contra-coxa (PCC), peso da coxa (PCX) e rendimento de carcaça (RCA). A análise de variância multivariada indicou diferença significativa entre os vetores de médias das características. Pelo teste de Roy, observou-se que para PC e PP os produtos comerciais foram superiores e para PCX e RCA näo houve diferenças significativas entre os produtos comercias e os cruzamentos. Quanto à funçäo discriminante linear de Fisher, observou-se superioridade significativa dos produtos comerciais pelo teste de Roy

Avaliação de frangos de corte utilizando técnicas de análise multivariada: I - Características de carcaça

Multivariate analyses were used to compare two hybrids obtained from two strains of broilers developed by Federal University of Viçosa (UFV) with two commercial hybrids. The evaluated traits were: slaughter weight (PAB), carcass weight (PC), breast weight (PP), upper thigh weight (PCC), thigh weight (PCX) and carcass yield (RCA). Multivariate analyses, showed significant differences among mean vectors of traits. The Roy test indicated the commercial products were better for PC and PP, and no differences between commercial products and UFV crosses were observed for PCX and RCA. The discriminant linear function of Fisher also indicated that commercial products were better than UFV crosses by the test of Roy.

Foram utilizadas técnicas de análise multivariada para comparar dois híbridos obtidos de linhas de frango de corte desenvolvidas pela Universidade Federal de Viçosa com dois híbridos comerciais. As características avaliadas foram: peso ao abate (PAB), peso da carcaça (PC), peso do peito (PP), peso da contra-coxa (PCC), peso da coxa (PCX) e rendimento de carcaça (RCA). A análise de variância multivariada indicou diferença significativa entre os vetores de médias das características. Pelo teste de Roy, observou-se que para PC e PP os produtos comerciais foram superiores e para PCX e RCA não houve diferenças significativas entre os produtos comercias e os cruzamentos. Quanto à função discriminante linear de Fisher, observou-se superioridade significativa dos produtos comerciais pelo teste de Roy.