The ontogenetic allometry of body morphology and chemical composition in dairy goat wethers

We studied the ontogenetic growth of goat wethers (castrated male goats) of the Saanen and Swiss Alpine breeds based on a large range of intraspecific body mass (BM). The body parts and the chemical constituents of the empty body were described by the allometric function by using BM and the empty bo...

Full description

Bibliographic Details
Main Authors: R.A.M. Vieira, N.M. Rohem Júnior, R.S. Gomes, T.S. Oliveira, L.C.R. Bendia, F.H.V. Azevedo, D.L. Barbosa, L.S. Glória, M.T. Rodrigues
Format: Article
Language:English
Published: Elsevier 2018-01-01
Series:Animal
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S1751731117001884
_version_ 1818894452272398336
author R.A.M. Vieira
N.M. Rohem Júnior
R.S. Gomes
T.S. Oliveira
L.C.R. Bendia
F.H.V. Azevedo
D.L. Barbosa
L.S. Glória
M.T. Rodrigues
author_facet R.A.M. Vieira
N.M. Rohem Júnior
R.S. Gomes
T.S. Oliveira
L.C.R. Bendia
F.H.V. Azevedo
D.L. Barbosa
L.S. Glória
M.T. Rodrigues
author_sort R.A.M. Vieira
collection DOAJ
description We studied the ontogenetic growth of goat wethers (castrated male goats) of the Saanen and Swiss Alpine breeds based on a large range of intraspecific body mass (BM). The body parts and the chemical constituents of the empty body were described by the allometric function by using BM and the empty body mass (EBM) as the predictors for morphological traits and chemical composition, respectively. We fitted the allometric scaling function by applying the SAS NLMIXED procedure, but to evaluate assumptions regarding variances in morphological and compositional traits, we combined the scaling function with homoscedastic (MOD1), and the heteroscedastic exponential (MOD2) and power-of-the-mean (MOD3) variance functions. We also predicted the ontogenetic growth by using the traditional log-log transformation and back-transformed results into the arithmetic scale (MOD4). We obtained predictions from MOD4 in the arithmetic scale by a two-step process, and evaluated MOD1, MOD2 and MOD3 by a model selection framework, and compared MOD4 with MOD1, MOD2 and MOD3 based on goodness-of-fit measures. Based on information criteria for model selection, heterogeneous variance functions were more likely to describe 10 over 36 traits with a low level of model selection uncertainty. One trait was predicted by averaging the MOD1 and MOD2 variance functions; and nine traits were better described by averaging the MOD2 and MOD3 variance functions. The predictions for other 16 traits were averaged from MOD1, MOD2 and MOD3. However, MOD4 better described 11 traits according to the goodness-of-fit measures. Depending on the variable being analyzed, the body parts and the chemical amounts exhibited the three types of allometric behavior with respect to BM and EBM, that is, positive, negative and isometric ontogenetic growth. Reference BMs, that is, 20, 27, 35 and 45 kg, were used to compute the net protein and energy requirements based on the first derivative of the scaling function, and the results were presented in reference to the EBM and EBM0.75. Both the net protein and energy requirements scaled to EBM0.75 increased from 20 to 45 kg of BM.
first_indexed 2024-12-19T18:28:43Z
format Article
id doaj.art-8f86684bb55a4ecd8619e4965729b388
institution Directory Open Access Journal
issn 1751-7311
language English
last_indexed 2024-12-19T18:28:43Z
publishDate 2018-01-01
publisher Elsevier
record_format Article
series Animal
spelling doaj.art-8f86684bb55a4ecd8619e4965729b3882022-12-21T20:10:46ZengElsevierAnimal1751-73112018-01-01123538553The ontogenetic allometry of body morphology and chemical composition in dairy goat wethersR.A.M. Vieira0N.M. Rohem Júnior1R.S. Gomes2T.S. Oliveira3L.C.R. Bendia4F.H.V. Azevedo5D.L. Barbosa6L.S. Glória7M.T. Rodrigues8Laboratório de Zootecnia, Centro de Ciências e Tecnologias Agropecuárias (CCTA), Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Av. Alberto Lamego 2000, Campos dos Goytacazes, RJ, CEP 28013-602, BrazilAnimal Science Graduate Program, CCTA/UENF, Campos dos Goytacazes, RJ, CEP 28013-602, BrazilAnimal Science Graduate Program, CCTA/UENF, Campos dos Goytacazes, RJ, CEP 28013-602, BrazilAnimal Science Graduate Program, CCTA/UENF, Campos dos Goytacazes, RJ, CEP 28013-602, BrazilAnimal Science Graduate Program, CCTA/UENF, Campos dos Goytacazes, RJ, CEP 28013-602, BrazilAnimal Science Graduate Program, CCTA/UENF, Campos dos Goytacazes, RJ, CEP 28013-602, BrazilAnimal Science Graduate Program, CCTA/UENF, Campos dos Goytacazes, RJ, CEP 28013-602, BrazilLaboratório de Zootecnia, Centro de Ciências e Tecnologias Agropecuárias (CCTA), Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Av. Alberto Lamego 2000, Campos dos Goytacazes, RJ, CEP 28013-602, BrazilDepartamento de Zootecnia, Centro de Ciências Agrárias, Universidade Federal de Viçosa, Viçosa, MG, CEP 36570-000, BrazilWe studied the ontogenetic growth of goat wethers (castrated male goats) of the Saanen and Swiss Alpine breeds based on a large range of intraspecific body mass (BM). The body parts and the chemical constituents of the empty body were described by the allometric function by using BM and the empty body mass (EBM) as the predictors for morphological traits and chemical composition, respectively. We fitted the allometric scaling function by applying the SAS NLMIXED procedure, but to evaluate assumptions regarding variances in morphological and compositional traits, we combined the scaling function with homoscedastic (MOD1), and the heteroscedastic exponential (MOD2) and power-of-the-mean (MOD3) variance functions. We also predicted the ontogenetic growth by using the traditional log-log transformation and back-transformed results into the arithmetic scale (MOD4). We obtained predictions from MOD4 in the arithmetic scale by a two-step process, and evaluated MOD1, MOD2 and MOD3 by a model selection framework, and compared MOD4 with MOD1, MOD2 and MOD3 based on goodness-of-fit measures. Based on information criteria for model selection, heterogeneous variance functions were more likely to describe 10 over 36 traits with a low level of model selection uncertainty. One trait was predicted by averaging the MOD1 and MOD2 variance functions; and nine traits were better described by averaging the MOD2 and MOD3 variance functions. The predictions for other 16 traits were averaged from MOD1, MOD2 and MOD3. However, MOD4 better described 11 traits according to the goodness-of-fit measures. Depending on the variable being analyzed, the body parts and the chemical amounts exhibited the three types of allometric behavior with respect to BM and EBM, that is, positive, negative and isometric ontogenetic growth. Reference BMs, that is, 20, 27, 35 and 45 kg, were used to compute the net protein and energy requirements based on the first derivative of the scaling function, and the results were presented in reference to the EBM and EBM0.75. Both the net protein and energy requirements scaled to EBM0.75 increased from 20 to 45 kg of BM.http://www.sciencedirect.com/science/article/pii/S1751731117001884bivariate allometrymodel averagingheteroscedasticitySaanenSwiss Alpine
spellingShingle R.A.M. Vieira
N.M. Rohem Júnior
R.S. Gomes
T.S. Oliveira
L.C.R. Bendia
F.H.V. Azevedo
D.L. Barbosa
L.S. Glória
M.T. Rodrigues
The ontogenetic allometry of body morphology and chemical composition in dairy goat wethers
Animal
bivariate allometry
model averaging
heteroscedasticity
Saanen
Swiss Alpine
title The ontogenetic allometry of body morphology and chemical composition in dairy goat wethers
title_full The ontogenetic allometry of body morphology and chemical composition in dairy goat wethers
title_fullStr The ontogenetic allometry of body morphology and chemical composition in dairy goat wethers
title_full_unstemmed The ontogenetic allometry of body morphology and chemical composition in dairy goat wethers
title_short The ontogenetic allometry of body morphology and chemical composition in dairy goat wethers
title_sort ontogenetic allometry of body morphology and chemical composition in dairy goat wethers
topic bivariate allometry
model averaging
heteroscedasticity
Saanen
Swiss Alpine
url http://www.sciencedirect.com/science/article/pii/S1751731117001884
work_keys_str_mv AT ramvieira theontogeneticallometryofbodymorphologyandchemicalcompositionindairygoatwethers
AT nmrohemjunior theontogeneticallometryofbodymorphologyandchemicalcompositionindairygoatwethers
AT rsgomes theontogeneticallometryofbodymorphologyandchemicalcompositionindairygoatwethers
AT tsoliveira theontogeneticallometryofbodymorphologyandchemicalcompositionindairygoatwethers
AT lcrbendia theontogeneticallometryofbodymorphologyandchemicalcompositionindairygoatwethers
AT fhvazevedo theontogeneticallometryofbodymorphologyandchemicalcompositionindairygoatwethers
AT dlbarbosa theontogeneticallometryofbodymorphologyandchemicalcompositionindairygoatwethers
AT lsgloria theontogeneticallometryofbodymorphologyandchemicalcompositionindairygoatwethers
AT mtrodrigues theontogeneticallometryofbodymorphologyandchemicalcompositionindairygoatwethers
AT ramvieira ontogeneticallometryofbodymorphologyandchemicalcompositionindairygoatwethers
AT nmrohemjunior ontogeneticallometryofbodymorphologyandchemicalcompositionindairygoatwethers
AT rsgomes ontogeneticallometryofbodymorphologyandchemicalcompositionindairygoatwethers
AT tsoliveira ontogeneticallometryofbodymorphologyandchemicalcompositionindairygoatwethers
AT lcrbendia ontogeneticallometryofbodymorphologyandchemicalcompositionindairygoatwethers
AT fhvazevedo ontogeneticallometryofbodymorphologyandchemicalcompositionindairygoatwethers
AT dlbarbosa ontogeneticallometryofbodymorphologyandchemicalcompositionindairygoatwethers
AT lsgloria ontogeneticallometryofbodymorphologyandchemicalcompositionindairygoatwethers
AT mtrodrigues ontogeneticallometryofbodymorphologyandchemicalcompositionindairygoatwethers