Random regression models with different residual variance structures for describing litter size in swine

Objetivou-se comparar modelos de regressão aleatória com diferentes estruturas de variância residual, a fim de se buscar a melhor modelagem para a característica tamanho da leitegada ao nascer (TLN). Utilizaram-se 1.701 registros de TLN, que foram analisados por meio de modelo animal, unicaracterística, de regressão aleatória. As regressões fixa e aleatórias foram representadas por funções contínuas sobre a ordem de parto, ajustadas por polinômios ortogonais de Legendre de ordem 3. Para averiguar a melhor modelagem para a variância residual, considerou-se a heterogeneidade de variância por meio de 1 a 7 classes de variância residual. O modelo geral de análise incluiu grupo de contemporâneo como efeito fixo; os coeficientes de regressão fixa para modelar a trajetória média da população; os coeficientes de regressão aleatória do efeito genético aditivo-direto, do comumde-leitegada e do de ambiente permanente de animal; e o efeito aleatório residual. O teste da razão de verossimilhança, o critério de informação de Akaike e o critério de informação bayesiano de Schwarz apontaram o modelo que considerou homogeneidade de variância como o que proporcionou melhor ajuste aos dados utilizados. As herdabilidades obtidas foram próximas a zero (0,002 a 0,006). O efeito de ambiente permanente foi crescente da 1a (0,06) à 5a (0,28) ordem, mas decrescente desse ponto até a 7a ordem (0,18). O comum-de-leitegada apresentou valores baixos (0,01 a 0,02). A utilização de homogeneidade de variância residual foi mais adequada para modelar as variâncias associadas à característica tamanho da leitegada ao nascer nesse conjunto de dado.The objective of this work was to compare random regression models with different residual variance structures, so as to obtain the best modeling for the trait litter size at birth (LSB) in swine. One thousand, seven hundred and one records of LSB were analyzed. LSB was analyzed by means of a random-regression, single-characteristic animal model. The fixed and random regressions were represented by continuous functions over the farrowing order, adjusted by third-order Legendre’s orthogonal polynomials. To obtain the best modeling for the residual variance, variance heterogeneity was assumed by means of 1 to 7 classes of residual variance. The general analysis model included a contemporary group; the fixed regression coefficients for modeling the population’s average trajectory; the random regression coefficients of the direct additive genetic effects both of the litter and of the animal’s permanent environment; and the residual random effect. The likelihood-ratio test, Akaike’s information criterion, and Schwarz’s Bayesian information criterion appointed the model that considered variance homogeneity as being the one that provided the best adjustment to the data used. Overall, the heritabilities obtained were close to zero (0.002 to 0.006). Regarding the permanent environment proportion, different magnitudes were observed for the farrowing order: increasing from the 1st (0.06) to the 5th (0.28) orders and decreasing from there to the 7th order (0.18). The common litter effect presented low values (from 0.01 to 0.02). The use of residual variance homogeneity was more suitable for modeling variances associated to the trait litter size at birth in this data set.publishe

Genetic diversity of the Brazilian Creole cattle Pe-duro assessed by microsatellites and mitochondrial DNA

The objective of this study was to describe the genetic diversity and structure of the largest Pe-duro population by assessing variation at ten autosomal microsatellite (STR) loci and mitochondrial DNA (mtDNA) sequences. The mean expected heterozygosity was 0.755, the mean observed heterozygosity was 0.600 and significant inbreeding coefficient (Fis) and deviations from the Hardy-Weinberg equilibrium in most of analyzed loci demonstrate the impact of inbreeding and homozygosis on this population. A more in-depth genetic analysis could be achieved by expanding the STR list. The analysis of mtDNA provided evidence of ancestral African taurine haplotypes in Pe-duro and excluded maternal Zebuine introgression. In this report, the main Pe-duro population is genetically portrayed by sampling approximately 40% of it. As this herd represents the core of the Pe-duro conservation program, these findings are of outstanding value for the management and preservation of this Brazilian 'native' cattle breed.National Council for Scientific and Technological Development (CNPq)National Council for Scientific and Technological Development - CNPqFoundation to Support Education, Research and Care of the Hospital of the Medical School of Ribeirao Preto, Universidade de Sao Paulo - FAEPAFoundation to Support Education, Research and Care of the Hospital of the Medical School of Ribeirao Preto, Universidade de Sao Paulo FAEP

Age and weight estimate on the first breeding in the Brazilian Pantanal heifers

Esto trabajo tuvo como objetivo estimar la edad y peso a la primera monta de novillas de las razas Nelore (N), Pantaneira (P) y Mestizas Pantaneira x Nelore (PxN). Se utilizó un total de 98 hembras, siendo 51, 24 y 23 pertenecientes a las razas N, P y PxN, respectivamente. El análisis estadístico de los datos no reveló diferencia significativa (P = 0,3595) para el peso a la primera monta entre las razas estudiadas. El análisis de varianza no reveló diferencia significativa (P = 0,307) entre las edades a la primera monta entre razas, mostrando 3,5, 3,4 y 3,2 años para las novillas P, N y ½PxN, respectivamenteThe objective of this work was to estimate the age and live weight at the first breeding in the Nelore (N), Pantaneira (P), and crossbreeding Pantaneira x Nelore (PxN) heifers. A total of 98 females was used for treatments, 51, 24 and 23 from N, P and PxN heifers, respectively. The statistical analysis did not show any significant difference (P = 0.3595) to live weight in the first breeding among breeds. The variance analysis did not show any significant difference (P = 0.307) of age among breeds, showing 3.5, 3.4 and 3.2 years to P, N and ½PxN heifers, respectivel

Estimativa de la edad y peso a la primera monta de novillas en el Pantanal brasileño

The objective of this work was to estimate the age and live weight at the first breeding in the Nelore (N), Pantaneira (P), and crossbreeding Pantaneira x Nelore (PxN) heifers. A total of 98 females was used for treatments, 51, 24 and 23 from N, P and PxN heifers, respectively. The statistical analysis did not show any significant difference (P = 0.3595) to live weight in the first breeding among breeds. The variance analysis did not show any significant difference (P = 0.307) of age among breeds, showing 3.5, 3.4 and 3.2 years to P, N and ½PxN heifers, respectively.The objective of this work was to estimate the age and live weight at the first breeding in the Nelore (N), Pantaneira (P), and crossbreeding Pantaneira x Nelore (PxN) heifers. A total of 98 females was used for treatments, 51, 24 and 23 from N, P and PxN heifers, respectively. The statistical analysis did not show any significant difference (P = 0.3595) to live weight in the first breeding among breeds. The variance analysis did not show any significant difference (P = 0.307) of age among breeds, showing 3.5, 3.4 and 3.2 years to P, N and ½PxN heifers, respectively.Esto trabajo tuvo como objetivo estimar la edad y peso a la primera monta de novillas de las razas Nelore (N), Pantaneira (P) y Mestizas Pantaneira x Nelore (PxN). Se utilizó un total de 98 hembras, siendo 51, 24 y 23 pertenecientes a las razas N, P y PxN, respectivamente. El análisis estadístico de los datos no reveló diferencia significativa (P = 0,3595) para el peso a la primera monta entre las razas estudiadas. El análisis de varianza no reveló diferencia significativa (P = 0,307) entre las edades a la primera monta entre razas, mostrando 3,5, 3,4 y 3,2 años para las novillas P, N y ½PxN, respectivamente

Genetic diversity of asses’ five populations through the use of microsatellites markers

Genetic characterization of five asinine populations, corresponding to two Brazilian breeds (Nordestina - two populations - and Marchador Brasileiro), a local breed of Portugal (Burro de Miranda) and a diverse group of individuals from different Iberian populations was performed based on 193 animals. Fifteen microsatellites markers were analyzed in order to estimate the inter/intra population variability as well as to know the genetic relationship between Brazilian and Iberian asses. The results showed that the majority of loci were not at Hardy-Weinberg equilibrium in the investigated populations due to a significant excess of homozygotes (P<0.05). Brazilian populations are not linked to European populations. The two Nordestina breed populations showed a well-defined structure and can be considered as two distinct populations. The Conservation Nucleus of Marchador Brasileiro breed, however, showed two different clusters, probably due to its reduced size with individuals from different origins (FIS = 0.2714). These donkeys are a high priority for the conservation of genetic resources. The information generated by microsatellites can be used for mating strategies in order to recover their diversity, especially regarding to the excess of homozygotes. There will be a new sampling in this Nucleus, in order to know more precisely the level of inbreeding present to supervise its diversity

The genetic ancestry of American Creole cattle inferred from uniparental and autosomal genetic markers

Cattle imported from the Iberian Peninsula spread throughout America in the early years of discovery and colonization to originate Creole breeds, which adapted to a wide diversity of environments and later received influences from other origins, including zebu cattle in more recent years. We analyzed uniparental genetic markers and autosomal microsatellites in DNA samples from 114 cattle breeds distributed worldwide, including 40 Creole breeds representing the whole American continent, and samples from the Iberian Peninsula, British islands, Continental Europe, Africa and American zebu. We show that Creole breeds differ considerably from each other, and most have their own identity or group with others from neighboring regions. Results with mtDNA indicate that T1c-lineages are rare in Iberia but common in Africa and are well represented in Creoles from Brazil and Colombia, lending support to a direct African influence on Creoles. This is reinforced by the sharing of a unique Y-haplotype between cattle from Mozambique and Creoles from Argentina. Autosomal microsatellites indicate that Creoles occupy an intermediate position between African and European breeds, and some Creoles show a clear Iberian signature. Our results confirm the mixed ancestry of American Creole cattle and the role that African cattle have played in their development.Fil: Ginja, Catarina. Universidad de Porto. Facultad de Ciências. Centro de Investigação em Biodiversidade e Recursos Genéticos; PortugalFil: Gama, Luis Telo. Universidade de Lisboa. Faculdade de Medicina Veterinaria; PortugalFil: Cortés, Oscar. Universidad Complutense de Madrid; EspañaFil: Martin Burriel, Inmaculada. Universidad de Zaragoza; EspañaFil: Vega Pla, Jose Luis. Servicio de Cría Caballar de las Fuerzas Armadas. Laboratorio de Investigación Aplicada; EspañaFil: Penedo, Cecilia. University of California; Estados UnidosFil: Sponenberg, Phil. Virginia-Maryland Regional College of Veterinary Medicine; Estados UnidosFil: Cañón Ferreras, Francisco Javier. Universidad Complutense de Madrid; EspañaFil: Sanz, Arianne. Universidad de Zaragoza; EspañaFil: Egito, Andrea Alves do. Embrapa Gado de Corte; BrasilFil: Alvares, Luz Angela. Universidad Nacional de Colombia; ColombiaFil: Giovambattista, Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; ArgentinaFil: Agha, Saif. Ain Shams University. Faculty of Agriculture, Animal Production Department; EgiptoFil: Rogberg Muñoz, Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; ArgentinaFil: Cassiano Lara, Maria Aparecida. Centro de Genética e Reprodução. Instituto de Zootecnia; BrasilFil: Delgado, Juan Vicente. Universidad de Córdoba; EspañaFil: Martinez, Amparo. Universidad de Córdoba; Españ

The genetic ancestry of American Creole cattle inferred from uniparental and autosomal genetic markers

Cattle imported from the Iberian Peninsula spread throughout America in the early years of discovery and colonization to originate Creole breeds, which adapted to a wide diversity of environments and later received influences from other origins, including zebu cattle in more recent years. We analyzed uniparental genetic markers and autosomal microsatellites in DNA samples from 114 cattle breeds distributed worldwide, including 40 Creole breeds representing the whole American continent, and samples from the Iberian Peninsula, British islands, Continental Europe, Africa and American zebu. We show that Creole breeds differ considerably from each other, and most have their own identity or group with others from neighboring regions. Results with mtDNA indicate that T1c-lineages are rare in Iberia but common in Africa and are well represented in Creoles from Brazil and Colombia, lending support to a direct African influence on Creoles. This is reinforced by the sharing of a unique Y-haplotype between cattle from Mozambique and Creoles from Argentina. Autosomal microsatellites indicate that Creoles occupy an intermediate position between African and European breeds, and some Creoles show a clear Iberian signature. Our results confirm the mixed ancestry of American Creole cattle and the role that African cattle have played in their development.Fil: Ginja, Catarina. Universidad de Porto. Facultad de Ciências. Centro de Investigação em Biodiversidade e Recursos Genéticos; PortugalFil: Gama, Luis Telo. Universidade de Lisboa. Faculdade de Medicina Veterinaria; PortugalFil: Cortés, Oscar. Universidad Complutense de Madrid; EspañaFil: Martin Burriel, Inmaculada. Universidad de Zaragoza; EspañaFil: Vega Pla, Jose Luis. Servicio de Cría Caballar de las Fuerzas Armadas. Laboratorio de Investigación Aplicada; EspañaFil: Penedo, Cecilia. University of California; Estados UnidosFil: Sponenberg, Phil. Virginia-Maryland Regional College of Veterinary Medicine; Estados UnidosFil: Cañón Ferreras, Francisco Javier. Universidad Complutense de Madrid; EspañaFil: Sanz, Arianne. Universidad de Zaragoza; EspañaFil: Egito, Andrea Alves do. Embrapa Gado de Corte; BrasilFil: Alvares, Luz Angela. Universidad Nacional de Colombia; ColombiaFil: Giovambattista, Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; ArgentinaFil: Agha, Saif. Ain Shams University. Faculty of Agriculture, Animal Production Department; EgiptoFil: Rogberg Muñoz, Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; ArgentinaFil: Cassiano Lara, Maria Aparecida. Centro de Genética e Reprodução. Instituto de Zootecnia; BrasilFil: Delgado, Juan Vicente. Universidad de Córdoba; EspañaFil: Martinez, Amparo. Universidad de Córdoba; Españ

The genetic ancestry of American Creole cattle inferred from uniparental and autosomal genetic markers

Cattle imported from the Iberian Peninsula spread throughout America in the early years of discovery and colonization to originate Creole breeds, which adapted to a wide diversity of environments and later received infuences from other origins, including zebu cattle in more recent years. We analyzed uniparental genetic markers and autosomal microsatellites in DNA samples from 114 cattle breeds distributed worldwide, including 40 Creole breeds representing the whole American continent, and samples from the Iberian Peninsula, British islands, Continental Europe, Africa and American zebu. We show that Creole breeds difer considerably from each other, and most have their own identity or group with others from neighboring regions. Results with mtDNA indicate that T1c-lineages are rare in Iberia but common in Africa and are well represented in Creoles from Brazil and Colombia, lending support to a direct African infuence on Creoles. This is reinforced by the sharing of a unique Y-haplotype between cattle from Mozambique and Creoles from Argentina. Autosomal microsatellites indicate that Creoles occupy an intermediate position between African and European breeds, and some Creoles show a clear Iberian signature. Our results confrm the mixed ancestry of American Creole cattle and the role that African cattle have played in their development.Este trabajo tiene una enmienda, a la que puede accederse haciendo clic en el primer enlace de "Documentos relacionados".Facultad de Ciencias Veterinaria