Banca de DEFESA: MARCELA PORTELA SANTOS DE FIGUEIREDO

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : MARCELA PORTELA SANTOS DE FIGUEIREDO
DATE: 30/11/2023
TIME: 14:00
LOCAL: Deinfo
TITLE:

The generalized composition that generates growth/degrowth models applied to agricultural sciences

KEY WORDS:

Non-linear models; Animal growth; In vitro gas production technique; Model composition.

PAGES: 126
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUMMARY:

The objectives of this work were: To generalize the method of Santos et al (2019), adding the operation of function composition to the method and to create new models applied to agricultural science data. The first chapter is a literature review related to growth models applied to animal growth and the kinetics of gases produced by the in vitro technique. In the second chapter, the generalization of the method by Santos et al. (2019), adding the function composition operation. A new unicompartmental model was presented, created by the composition of the Brody model with that of Von Bertalanffy, which was applied to animal growth data of male chickens of the Antenas-Canada breed. The parameters were estimated using the least squares method of the R® software, using the nlsm function that uses the Levenberg-Marquardt algorithm. The proposed model was compared to the models: Logistic, Brody, Von Bertalanffy, Gompertz, Richards, through the criteria of goodness of fit Adjusted Coefficient of Determination R_(aj.)^2, Mean Square of the Residue (QMR), Information Criterion of Akaike (AIC) and Mean Absolute Deviation (DMA), Baysian Information Criterion (BIC), Adaptively Penalizing Likelihood (PAL) and Model Predictive Ability (ρ) to define the best model. The proposed model was the most adequate to fit the data of Athens Canadian Random Bred cockerels. Therefore, this work contributed, adding the composition operation. Furthermore, the model generated by this method is effective to fit data from Athens-Canada chickens. In the third chapter of the thesis, the stabilization points of the modified Logistic model (Shofiel, Pitt and Pell, 1994) were deduced and calculated and applied to the gas production of 7 experimental diets. These points were calculated for each compartment of the bicompartmental logistic model that was used to model the phenomenon. The stabilization points proved to be important to biologically interpret the studied phenomenon. The diets: semi-simplified based on a mixture of flour from cassava leaves and alfalfa hay, semi-simplified based on alfalfa hay and simplified based on a mixture of flour from cassava leaves and alfalfa hay, showed good results and are alternatives to the reference diet for feeding New Zealand rabbits.

COMMITTEE MEMBERS:
Externo à Instituição - CICERO CARLOS RAMOS DE BRITO - IFPE
Interno - FRANK SINATRA GOMES DA SILVA
Presidente - GUILHERME ROCHA MOREIRA
Interno - JOSIMAR MENDES DE VASCONCELOS
Externo à Instituição - JOÃO DE ANDRADE DUTRA FILHO - UFPE