Análise multivariada das medidas morfométricas de potros da raça Mangalarga Marchador: análise de componentes principais

Abstract

RESUMO -Objetivou-se, com este trabalho, a avaliação morfométrica de potros da raça Mangalarga Marchador, a partir da análise de componentes principais. As medidas corporais foram efetuadas na semana do nascimento dos potros, em 55 potros e 41 potras; aos seis meses de idade, em 35 potros e 37 potras; e aos 12 meses de idade, em 19 potros e 31 potras. Foram efetuadas 25 mensurações lineares, envolvendo altura, comprimento, largura e perímetros, e 11 mensurações angulares. Na avaliação dos animais com 12 meses de idade, foram consideradas apenas 19 medidas lineares, além das 11 angulares. Nas potras e potros recém-nascidos, a análise reduziu o número de medidas lineares de 25 para 7 e 9, respectivamente, enquanto nas medidas angulares, a redução foi de 11 para 6 e 7, nas potras e potros, respectivamente. Nas potras e potros com seis meses de idade, observou-se decréscimo no número de medidas lineares de 25 para 8 e 9, respectivamente, enquanto nas medidas angulares, a redução foi de 11 para 6, em ambos os sexos. Nas potras e potros com 12 meses de idade, a redução das medidas lineares foi de 19 para 6 e 5, respectivamente, enquanto nas medidas angulares, de 11 para 6 e 5, nas potras e potros, respectivamente. A análise dos componentes principais foi eficiente em reduzir o número de medidas lineares e angulares necessárias para a avaliação morfométrica de potros, sendo a redução maior entre as medidas lineares do que entre as angulares, entretanto, os dois primeiros componentes principais, nas diferentes idades estudadas, não conseguiram explicar 80% da variação total disponível, o que impossibilitou a interpretação em um plano bidimensional. Palavras-chave: medidas angulares, eqüinos, medidas lineares, morfologia Multivariate Analysis of the Body Measures in Mangalarga Marchador Foals: Principal Components AnalysisABSTRACT -This work aimed to evaluate body measures of colts and fillies of Mangalarga Marchador breed with principal components analysis. Measures were performed at birth week, in 55 colts and 41 fillies; at six months of age, in 35 colts and 37 fillies; and at twelve months of age, in 19 colts and 31 fillies. There were made 25 linear measures, including height, length, width and girth, and 11 angular measures. Evaluation of animals with 12 months of age was made with 19 linear and 11 angular measures. Analysis of linear measures in newly born reduced the number of measures from 25 to 7 and 9 in fillies and colts, respectively, while for angular measures the reduction was from 11 to 6 and 7 in the fillies and colts, respectively. Analysis of linear measures in animals with six months age reduced the number of measures from 25 to 8 and 9, in the fillies and colts, respectively, while for angular measures the reduction was from 11 to 6, in both sexes. At twelve months of age the reduction of linear measures was from 19 to 6 and 5, for fillies and colts, respectively, while for angular measures the reduction was from 11 to 6 and 5, for fillies and colts, respectively. Principal components analysis was ef...

Principal component analysis of linear measures of young horses national champions of Mangalarga Marchador breed

“…The F-MB group showed the greatest variation with up to five PC. PINTO et al (2005) observed an even greater number of PC finding seven components to explain a minimum percentage of 80% of the total variation of horses less than 12 months old. Therefore, it is suggested that the younger the animal, the greater the variance of the body parts.…”

“…Comparisons of individual measurements demonstrate that trot horses have smaller widths between the eyes and jaw, as well as proportionally longer segments in the forelimbs, and thinner circumferences in the lower parts of these limbs (STAIGER et al, 2016). The selection of the MM breed gave the animals a smaller head, shorter body length, a larger diameter of the bone rays and an increase in the size of these animals within the standard values of the breed (PINTO et al, 2005). However, similarities and differences in conformation within the race can be noticed in relation to gender and type of marcha, especially regarding measurements related to limb flexion, frequency, and stride length (SANTIAGO et al, 2014).…”

“…Individuals with different gaits standarts, marcha batida or picada, do not come from different populations, and may be born with one phenotype or another (FONSECA et al, 2017). This gait characteristic of MM results from neuromotor coordination of movements, training and appropriate morphometric measures (PINTO et al, 2005).…”

Principal components for the in vivo and carcass conformations of Anglo-Nubian crossbred goats

“…This strong dimensional reduction had already been reported in other species, but the present study is the first to indicate this possibility also in goats. In newly born Mangalarga Marchador horses, PINTO et al (2005) applied PCA for morphometric measurements and observed a reduction from 25 to seven and nine in females and males, respectively, while for angular measurements the reduction was from 11 to six and seven traits in females and males, respectively. BARBOSA et al (2005) whole leg weight; breast weight; abdominal fat pad weight; weights of liver, gizzard, and heart; and carcass dry matter, fat, and crude protein contents, and of the11 quail carcass traits assessed, only four were sufficient for explaining a large variance percentage.…”

“…PINTO et al (2005), used PCA to identify redundant morphometric traits in Mangalarga Marchador horses. Similarly, BARBOSA et al (2005), applied PCA to 33 carcass traits in a swine population and identified 17 redundant traits.…”