Assessment of spatial variability of bedding variables in compost bedded pack barns with climate control system

Abstract

The aim of this research was to evaluate the spatial distribution of bedding variables in a climate-controlled compost bedded pack barn (CBP) equipped with an evaporative cooling system associated with a tunnel ventilation mode. The study was conducted on a farm in the West Mesoregion of Minas, MG, Brazil. The interior of the animal facility was divided into a mesh of 120 equidistant points, where the bedding surface temperature (t_b-sur), the bedding temperature at 0.20 m depth (t_b-20) and the bedding penetration resistance (PR_b) of layer 0 to 0.20 m depth were measured. Bedding samples were collected to obtain the moisture (M_b) and pH in the surface and at 0.20 m depth. Geostatistics technique was used to evaluate the dependence and spatial distribution. Through the bedding area, the t_b-sur presented low variability, with 6 ºC of amplitude, and t_b-20 presented highest values (up to 55 °C). The spatial distribution of M_b-20 was similar to that observed on the surface and its highest levels occurred in the region near the feed alley (> 40%). The distribution of pH was similar in both layers. The tendency of high PR_b occurred in the layer between 0.15 and 0.20 m (0 and 1500 kPa).

Key words
dairy cattle; compost barns; geostatistics; spatial variability