Adjustment of non-linear models for growth in Morada Nova sheep breed / Ajuste de modelos não lineares para o crescimento em ovinos da raça Morada Nova
Contini, Ênio; Junqueira Oliveira, Elisa; Lopes Dias Costa, Ricardo; Geraldi Mendonça, Gabriela; Eugênio Vercesi Filho, Aníbal; Fernanda Simili, Flavia; El Faro, Lenira; Cristina Paro de Paz, Claudia.
B. Indústr. Anim.;
71: 30-30, 2014.
Artigo
em Inglês
| VETINDEX
| ID: vti-467241
Resumo
Performance evaluation of adapted animals to local conditions for economic traits is essential for the preservation of species and their genetic resources. The size of Morada Nova breed herds have decreased over time, becoming restricted to a few regions. Other races have been used with higher frequency because of their production and adaptation, and are important as a source of food and income for local communities. The objective of this research was to evaluate the application of nonlinear models to describe the growth curve of Morada Nova sheep. Records of 1604 weights of 250 lambs from Nova Odessa municipality, being 934 repeated measurements of female and 670 repeated measurements of male, obtained between 2012-2013 were used. The average birth weight observed was 2.50 ± 0.690 kg. The nonlinear models used to adjust the data were Brody Yt = A (1 - be-kt); Von Bertalanffy Yt = A (1 - be-kt)3; Richards Yt = A (1 - be-kt)m; Logistic Yt = A (1 + e-kt)-m and Gompertz Yt = Ae -be(-kt). The models were fitted by Gauss-Newton using the NLIN procedure of SAS (SAS Inst., Inc., Cary, NC). The parameters that make up the functions are Y = body weight at the age t; A = asymptotic weight that represents the average adulthood weight; K = Maturation rate, an indicator of the speed with which the animal approaches its adult size, maturity of the individual in relation to age is the fractioO artigo não apresenta resumo em português.
Biblioteca responsável:
BR68.1
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