[Microflora in swine slurry as a parameter in determining the efficiency of deodorizing treatment. I. Continuous and discontinuous aeration treatment].

Liquid manure from the pig, fresh and stored, was treated by continuous and discontinuous aeration. The purpose was to achieve a biologically stabilized and deodorized organic material. The samples which were aerated intermittently had good decomposition rates for nitrogen compounds and even so good deodorization effects. In spite of a minimum of dissolved oxygen of appr. 0.2 mg/l, good deodorization could be achieved by intermittent aeration for 23 days. Simultaneous processes of nitrification and denitrification were observed in optimal aerated manure similar to activated sludge processes. On the other hand, significant shifts on the microflora could be shown, whereby the main part of the biota consists in the gramnegative, non fermentative organisms. In non-deodorized liquid manure, members of the genus Bacillus advanced in their growth rates. In addition to Alcaligenes-Pseudomonas organisms, the group of nonfermentative cocci (e. g. Moraxella spp., Paracoccus spp.) dominated. Their growth development during the treatment agreed very well with the results of decomposition and deodorization. The existence of Bifidobacterium and of Aerococcus in aerated pig slurry was not ascribed before.