CHEMICAL CHARACTERIZATION OF PIG MANURE DRY AND MATURE ORIGINATING FROM THREE LEVELS OF ENERGY

Abstract

The objective of this study was to determine the optimal conditions of the diet that will generate excreta of pigs with a chemical composition more suited to the needs of organic fertilizers. Twelve pigs were subjected to three levels of maintenance metabolizable energy (EMM): high (3.5 EMM), medium (2.5 EMM) and low (1.5 EMM). A portion of the excreta was collected composting to maturity. Factorial design was used and data were statistically analyzed using SAS version 9.0. The measured variables included feed and grass intake, manure production, total nitrogen, carbon, temperature, pH and C/ N ratio. The highest feed intake was corresponded to the high energy level (1.112 kg/d), while the low and medium energy levels had higher grass/forage intake values (0.103 and 0.095 kg/day). The high energy level recorded increased total dry matter (DM) consumption (1.197 kg/day), while the excreta production was higher in the low and medium energy levels (0.298 and 0.295 kg/day). During the 21 days of composting period, the high and medium energy levels recorded higher temperatures (60 °C) versus the low energy group (58 °C). Regarding the pH, no significant differences were detected. Among the tested energy levels, the low level showed highest C/N ratio (10.0:1). The mature excreta had higher C/N ratio (10.6:1) as compared to the dry excreta (8.1:1).