Analysis of internal environment in individual houses with different coverages for calves undergoing a program of supplementary light

• Grant number: 10/08271-5
• Support type: Scholarships in Brazil - Doctorate
• Effective date (Start): December 01, 2010
• Effective date (End): March 31, 2012
• Field of knowledge: Agronomical Sciences - Animal Husbandry
• Principal researcher: Holmer Savastano Junior
• Grantee: Priscilla Ayleen Bustos Mac-Lean
• Home Institution: Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil

Abstract

This project aims to assess the physical installation for individual housing of calves at weaning, through the analysis of different types of coverage and their indexes of thermal comfort in the microenvironment. Moreover, it will seek the optimization of ingestive behavior, through a program of supplemental light. The analysis of both aspects listed above will happen in two phases, in search of better performance. The first will analyze the thermal performance of roofing tile cement and recycled material with and without aluminum coating from thermal comfort indices (radiant heat load, black globe temperature index and temperature and humidity index) calculated based on air temperature, black globe temperature, dew point temperature, wind speed and relative humidity. The second phase will be installed next to a tropical system of huts for calves, box type, with one calf per experimental unit, during the summer 2011. Will be used 24 Jersey calves housed in calving with coverage of the tile that provide the best results in the first phase. Two treatments are compared, one with a program of supplementary light, which will consist of 18 hours of light and 6 hours of artificial light per day, compared with plants without artificial lighting. Will also be measured the physiological thermoregulation of animals (respiratory rate, rectal temperature, surface temperature and body temperature flow), development variables (height, thoracic circumference and length of the animal) and blood variables. Ingestive behavior is analyzed in three stages of the experiment (first, fifth and seventh weeks) and the behavior before the system of supplementary light. As a result, it is expected that the environments covered by the tiles provide thermal comfort for the animal to perform its normal behavior and that the program of light differentiates the food intake of the calves so they can spend the growing phase in less time.