Deficiencies of Ventilation on the Microclimate Hall of Laying Hens

Abstract

Welfare of laying hens, production are conditioned microclimate (Teusdea V., 1996). The study was conducted in a hall laying hens, growing bedding permanently, with poor ventilation and microclimate of impaired hall. Axial fans in the number 2 is located on the same wall, filled with natural through the mouths of the inlet located 30 cm from the ground on the longitudinal walls. In the paper referred to the factors temperature, temperature and pH of the litter, the concentration of ammonia. Determinations are made at the ends and center hall laying hens at breathing level (BL) and 1 m from the ground (1m). pH was determined in surface and depth and temperature the sameat litter level. Temperature recorded in the present winter season between 19.5-20.2C B.L, slightly higher values at 1m, influenced by the presence heating system located at distance of 2.2 m from the ground. In the warm season the value growing from one hour to another, which shows poor ventilation capacity, the values situating during the day between 20.2-27C far from the limit of confort 13-19C (MAN.C., 2007); litter on the surface temperature is 18-23.4C in depth 19.8-25C, pH litter surface 8.6-9 pH unit, in depth: 8.7-9.4 pH unit. Temperature and pH favors increased litter decomposition processes of organic matter which is reflected by an increased release of NH3, values obtained at 10 ppm BL-7 ppm (1m), in winter months and peak season for hot 20ppm BL, 1 m (high values compared to the normal (MARIANA dine 2003); at the end of the fans are good, ranging between 5-7 ppm. Following the comparison of the three variables is found as follows: comparison of pH (8.78 ± 0.304 unit.pH) and litter temperature (21.76 ± 5.72C) shows very significant value P < 0.0001, (t = 10.13 for 38 G.L); comparison between litter temperature (21.76 ± 5.72C) and ammonia (9.83 ± 2.37 ppm) is very significant. In conclusion: litter temperature is the decisive factor in increasing the pH level of litter and ammonia production.