Studies On Biology Bed For Feeder Pigs

Biology-Bed is a housing system where the mixture of bedding, faeces and urine is stored in a thick on the floor in the pen. The layer with organic material degrades aerobically in a slow composting process. One biology bed model was established in bench-scale laboratory, and was studied. The study conducted in three parts.Part1:Sawdust, soil, wheat bran and so on were mixed and made to two group of fermentation of high temperature and low temperature. Four pigs with 20 kg BW were fed in low temperature groups. Bedding temperature in top, middle and bottom layer was measured. Ferment ability results showed that the temperature rose rapidly in high temperature fermentation group whose fermentation was formed, but lasted only eleven days; control group and low temperature fermentation group (before feeding pigs) were close to room temperature and the bedding didn't ferment. The temperature of dunging area in low temperature fermentation group (after feeding pigs) went stable in fifteen days and was kept in 52℃.It suggested that native biology bed was available and high temperature ferment can be used for epidemic prevention sanitation management after to kill bacteriums and worms.Part2:The concentration of PM₁₀ and the rate of ventilation indoor were measured, and the characteristics of production volume of dust and vapor were also analyzed, and then temperature of the bed on situations of adding sawdust and stop raising pig were masured, and studied the environment of the biology bed and one in Zhenjang TC. The results showed that the concentration of PM₁₀ descended among with the fermentation process and finally maintained in 0.254 mg/m³.The practical ventilation rate was 0.31m³/s.The volume of PM₁₀ and vapor produced from bedding was 1.453mg/min·m² and 0.198±0.010g /min·m² respectively. After adding sawdust, the temperature of the litter was raised about 6-11℃and it declined 16℃after stop raising pigs. The results in Zhenjiang TC show that the concentration of PM₁₀ in door was 0.392mg/m³ and NH₃ was 0.893mg/m³.There was very little propionic acid, and acetic acid and butyric acid can not be seen within the measurable area of the equipment, and aerobic fermentation was mostly.The concentration of cuprum in air-dried feces and the litter used 3years was 350mg/kg and 380mg/kg, and the concentration of cuprum in surface layer is 226 mg/kg which was higher than the middle layer's in litter used 1 year.Part3:The relationship between the resting position of pigs and thermal environment was studeed. During the temperature of environment between 29℃-32℃in summer and5.9℃-6.7℃in winter, the temperature of bio-bed around 31℃-37℃in summer and 17.5℃-23.8℃in winter.The average of respiration rate reached 57/min in summer and 22.8/min in winter.The proportion of resting position was 81% in summer and was only 47.8% in winter.The maintenance behavior on the concrete ground was highly to 73% in summer and he maintenance behavior on the bio-bed was highly to 83.6% in winter, and the proportion of scattering was 60% in summer and the proportion of physical contact was 37.0% in winter. The heat preservation of bio-bed put press on heat loss of pigs in summer, and had a good effect in winter.