Evaluation of ruminal pH continuous measurement methodology through accuracy, precision and robustness

• Grant number: 11/19531-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2011
• End date: May 31, 2012
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Nutrition and Feeding
• Principal Investigator: Carolina Tobias Marino
• Grantee: Beatriz Villar da Trindade
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The present research work aims to compare the ruminal pH standard measurement methodology to automatic continuous measurement through accuracy, precision and robustness. The standard methodology is defined by manual collection through vacuum pump in rumen cannulated animals and the measurement is performed by a pH sensor. The continuous automatic methodology is defined by a data logger system which is inserted in the rumen and pH measurement is automatically done with an interval previously defined. The data logger system which will be tested was acquired through financial support (FAPESP process nº 2008/55776-5) with import invoice INV-2009-98 under coordination of the researcher Prof. Dr. Paulo Henrique Mazza Rodrigues in the postdoc research of Dra. Carolina Tobias Marino (FAPESP process nº 2008/50805-7). Six cows nonpregnant and nonlactating cows with average body weight 730 ± 70 kg will be used in two Latin squares 3x3. Three treatments will be tested concerning different energetic sources in the diet: control, soybean and citrus pulp. Each experimental period will have 21 d where ruminal pH collection will be done at the last day at 0; 1.5; 3.0; 4.5; 6.0; 7.5; 9.0; 10.5 and 12 h after morning meal. The data loggers for continuous measurement will be maintained in the rumen during the same period of manual collection. The values of rumen pH obtained by the alternative method (continuous and continuous adjusted) will be compared to those obtained by the manua method for the evaluation of accuracy, precision and robustness.(AU)