Models for the analysis of growth curves for rearing tinamous (Rhynchotus rufescens) in captivity

Abstract

Growth curves models provide a visual assessment of growth as a function of time, and prediction body weight at a specific age. This study aimed at estimating tinamous growth curve using different models, and at verifying their goodness of fit. A total number 11,639 weight records from 411 birds, being 6,671 from females and 3,095 from males, was analyzed. The highest estimates of a parameter were obtained using Brody (BD), von Bertalanffy (VB), Gompertz (GP,) and Logistic function (LG). Adult females were 5.7% heavier than males. The highest estimates of b parameter were obtained in the LG, GP, BD, and VB models. The estimated k parameter values in decreasing order were obtained in LG, GP, VB, and BD models. The correlation between the parameters a and k showed heavier birds are less precocious than the lighter. The estimates of intercept, linear regression coefficient, quadratic regression coefficient, and differences between quadratic coefficient of functions and estimated ties of quadratic-quadratic-quadratic segmented polynomials (QQQSP) were: 31.1732±2.41339; 3.07898± 0.13287; 0.02689±0.00152; -0.05566±0.00193; 0.02349±0.00107, and 57 and 145 days, respectively. The estimated predicted mean error values (PME) of VB, GP, BD, LG, and QQQSP models were, respectively, 0.8353; 0.01715; -0.6939; -2.2453; and -0.7544%. The coefficient of determination (R²) and least square error values (MS) showed similar results. In conclusion, the VB and the QQQSP models adequately described tinamous growth. The best model to describe tinamous growth was the Gompertz model, because it presented the highest R² values, easiness of convergence, lower PME, and the easiness of parameter biological interpretation

Non-Linear Model to Describe Growth Curves of Commercial Turkey in the Tropics of Mexico

“…Based on the criteria established to compare the models, the best fit of the von Bertalanffy and the Gompertz models indicates that they can be used to model the growth curve of Hybrid turkey reared under the management conditions of tropical southern Mexico. These results agree with the findings of Tholon & Queiroz (2007) in tinamous (Rhynchotus rufescens), when comparing the von Bertalanffy, Gompertz, Logistic, Brody and quadratic-quadratic-quadratic segmented polynomial models. Sengul & Kiraz (2005) found that the Morgan-Mercer-Floding (MMF) model fitted better the data of Large White turkeys, followed by the Gompertz, Logistic, and Richards models.…”

“…Mature or asymptotic weight (A) estimates for the three models that converged was higher for males than for females, indicating that male turkeys matured more slowly and it took more time to reach mature body weight than female turkeys ( Table 2). The highest A value was obtained by the von Bertalanffy model and the lowest by the Logistic model, as previously reported by Tholon & Queiroz (2007) *A= Body weight at maturity; b= integration constant; k= relative growth coefficient or maturity index; T I = age at inflection point; W I =body weight at age of inflection point.…”

“…In Bronze turkey, Ersoy et al (2006) obtained k values of 0.39 and 0.24 kg/week for females and males, respectively. Tholon & Queiroz (2007), in tinamous, determined higher k values with the Logistic model (0.037 kg/day), followed by the Gompertz (0.050 kg/ day), the von Bertalanffy (0.005 kg/day) and the Brody (0.003 kg/day) models.…”

Estimation of (co)variance components and genetic parameters for weights of red-winged tinamou using random regression models

“…Using nonlinear functions to describe the growth of this bird, Tholon & Queiroz (2007) obtained estimates of mature weight, expressed as asymptotic weight, of 648.2 and 806.4 g when logistic and Brody models were applied, respectively.…”

Growth Models and Analysis of Crustacean Growth Data

“…logistic models when a = 0, a = 2/3, a → 1 and a = 2 as summarised in Figure 3.1 (Berry et al, 1988;Birch, 1999;Tholon & Queiroz, 2007).…”