Comparison of B-splines and non-linear functions to describe growth patterns and predict mature weight of female beef cattle

Abstract

The objective of this study was to compare the ability of Basis spline (B-spline) models and five non-linear functions (Richards, Brody, Von Bertalanffy, Gompertz and Logistic) to describe the growth of females of a beef cattle breed and predict cow mature weight (A). Random regression models that included animal variation within function parameters were fitted using mixed model procedures. Comparisons were made among these functions for goodness of fit, standardised residuals and biological interpretability of the growth curve parameters. The B-spline function showed the best goodness of fit and within non-linear functions, the Richards and Von Bertalanffy functions estimated bodyweight at different periods accurately. The method of fitting the residual variance that provided the best goodness of fit in the model was the constant plus power variance function. The Richards function was found to be the best non-linear function and was compared with the B-spline function to predict mature weight. When the A parameter was estimated using fixed effects, it had a low correlation with the actual mature weight of the cow and the use of this estimate yielded no more gain in predictive accuracy of mature weight than the use of average breed mature weight. When A was estimated using fixed and random effects, it had a moderate correlation with actual mature weight for the B-spline and Richards functions. The use of both types of effects to estimate the maturity index reduced the error compared with the use of average mature weight, especially for the B-spline function, which is recommended as the best function to describe animal growth and predict mature weight

Effects of Developmental Programming Caused by Maternal Nutrient Intake on Postnatal Performance of Beef Heifers and Their Calves

“…In our study, after the first calving, the calf LW at birth and growth rate were not affected by the early nutritional treatment, suggesting that maternal nutrition did not affect the performance of this second generation, at least during lactation. However, since females of these breeds reach maturity when they are 4 to 5 years old [29], further studies are needed to determine if the heifer growth delay at weaning would impact the attainment of adult weight and mature size. Regarding breed, PA heifers had higher growth rates during rearing, BCS at calving, and calf LW at weaning than PI heifers, in accordance with previous studies [30], which evidenced similar interbreed differences.…”

Comparison on accuracy of different nonlinear models in predicting growth of Podolica bulls

“…Moreover, Miguel et al (2012) found that the Brody model was the best to estimate the actual weight at different ages in castrated Brahman males, although the Gompertz model showed the best overall fit. In a recent study by Gano et al (2015) on Parda de Montaña breed, the Richards function provided the best goodness of fit as also suggested by DeNise and Brinks (1985) and Doren et al (1989). Moreover, Gano et al (2015) reported that the von Bertalanffy function also described the dataset satisfactorily, whereas the logistic equation had the worst fit.…”

“…In a recent study by Gano et al (2015) on Parda de Montaña breed, the Richards function provided the best goodness of fit as also suggested by DeNise and Brinks (1985) and Doren et al (1989). Moreover, Gano et al (2015) reported that the von Bertalanffy function also described the dataset satisfactorily, whereas the logistic equation had the worst fit. Goldberg and Ravagnolo (2015) analyzed the growth curves for Angus cows using different nonlinear models and the results showed that the Richards model was the best to fit the data.…”

Prediction of Live Body Weight Using Body Measurements for Jawa Brebes (Jabres) Cattle

“…Jabres cattle have strong correlation among body size parameter in every group except female Jabres cattle same or above 1 years old. It can be happen because the cattle growth after 2 years old did not obey the linear curve (Gano et al 2015). The same condition also happen for Bali cattle (Ni'am et al 2012).…”

“…Contrarily, the worst fit equation was obtained for female cattle with age same or above 1 years old. It can be happened because the growth of adult cattle after 2 years old is non-linear so the body weight prediction became harder (Gano et al 2015). The male cattle with age above 1 years only contained a few cattle with age above 2 years old, meanwhile the female cattle with age above 1aspects old contained many cattle with age above 2 years old.…”