Meta-analytical study of total production of heat of broiler

Abstract

The determination of the total heat production of broiler chicken is an essential step to correctly predict the feed intake. The correction of broilers' feed intake according to the environmental conditions is essential to ensure enough nutrients supply for maximum productive performance. The objective of this project is to conduct a meta-analytic study to adjust the parameters of a mathematical model to estimate the heat production of broiler chicken. The model to be adjusted is: THP = HS + HR+HC+HU+HE+HF, where THP is the total heat produced, HS is sensible heat loss by housed birds, HR sensible heat loss through respiration, HC sensible heat loss by facilities, HU heat loss through cutaneous evaporation, HE evaporative heat loss through respiration and HF heat loss by drinking water. The input values of the model are ambient temperature, mixing ratio of the air, live weight of the bird, temperature of the drinking water. The output values are the total heat production and heat loss of the bird. Publications with information about total heat production, sensible heat for birds housed, sensible heat loss by installations and cutaneous heat loss by evaporation will be selected. The papers will be carefully selected considering appropriateness of methodology and consistency of results. After mounting the database, cluster and principal components analysis will be applied to understand the relationship structure of the data and the group formation by dissimilarity. The information related to the proposed theoretical model and other variables will be charted to allow a descriptive analysis of the studies included in the database. The meta-analysis will follow three sequential analysis: the graphical plot analysis, pearson correlation analysis and analysis of variance and covariance. After the analysis will be maintained at the base information that was statistically significant for its effects. Thus, four parameters will be adjusted: HS, HC, HU and HE. The main result of this project will be to provide a practical mathematical model to estimate the heat production of broilers through papers published in the literature and incorporate the adjusted model in the software AVINESP, which was developed by the research group in animal nutrition and modeling of UNESP campus Jaboticabal. Besides the dissemination of the results through publications in conferences and journals, lectures will also be conducted to demonstrate how the software works and its benefits to users. (AU)