Economic valuation of zootechnical indicators in a tropical dairy goat production system

Abstract

The objective of our study was to promote advances in the economic valuation method of zootechnical indicators in dairy goat farming by incorporating the analysis of the modeling of biological relationships between the indicators. A Multiple Linear Regression model was developed to predict milk production as a function of zootechnical indexes and to determine which indicators influenced and in what proportion the quantity of liters sold. The absolute and relative economic values of these indicators were then calculated. Milk production was influenced by prolificacy (P=0.00325), age at kidding (P=0.01886), duration of lactation (P=< 2e-16) and parity number (P=0.00575), with absolute and relative economic values respectively as follows: $ 0,086/kid/female/year and 62.3% for prolificacy, -$ 0.001/female/month and -0.5% for age at kidding, $ 0.002/female/day and 1.5% for duration of lactation, and $ 0.051/female/parity and 36.7% for parity number. High values for the age at first kidding and interval between kiddings may be responsible for the effect of age and parity number. In conclusion, the procedures were herein employed and validated to improve the economic valuation method proved to be viable and efficient for application in dairy goat farming. In the situation analyzed, more than 90% of the economic value was obtained by prolificacy and parity number; however, the scarcity of research on these aspects of goat farming and the different indicators analyzed demonstrate the need for continuity of research in order to improve the methods so that their use in the field is applicable in more accessible ways.