Testing the effect of different concentrations of formalin for decontamination of cattle manure

Abstract

Comparative studies of the use of formalin in concentrations of 2% and 4% were carried out for the processing of fresh and aged manure litter from dairy cows with a view to decontamination. For this purpose, changes in the quantities of contained in fertilizer materials microorganisms were tracked, as well as of pathogenic test strains of Proteus vulgaris, Pseudomonas aeruginosa и Staphylococcus epidermidis, differing in resistance to gentamicin and tetracycline antibiotics. Test bacteria were imported in fertilizer materials in quantities of 105 CFU / g of their total contents. It was found that treatment with formalin in the two tested concentrations of 2% and 4% ensures inactivation of the pathogenic test microorganisms and of Clostridium perfringens, contained in the tested samples of fresh and aged manure, even after 24 h. Inactivation of Esherichia coli, found in both manure samples, processing with 2% formalin, was achieved in 48 h, and at a concentration of 4% - only in 24 h. In fresh manure after treatment with 4% formalin all microorganisms were killed after 96 h, and in aged manure - even after 72 h. Administration of 2% formalin ensures destruction of all microorganisms in fresh and aged cattle manure for a period of 120 h= The use of formalin in a final concentration of 4% does not give much better results than double the smallest concentration of 2%, which is recommended for use.