Quality and possible use of effluents from caiman farms

SIMONCINI, M. S.; LEIVA, P. M. L.; FORNI, M.; CARRIZO, M.; LARRIERA, A.; GONZALEZ, M.A.; PIÑA, C. I.; IMHOF, S.

Chetumal

Congreso; XXVI Working Meeting Crocodiles Specialist Group - UICN; 2022

Crocodiles Specialist Group - UICN

Caiman farms discard large volume of water andsuspended solids (rest of food and feces). Those effluents most of the times arestocked in pools without any use. Our objective was to characterize chemical,physical and microbiological residual waters of those lagoons (both at surface andbottom). The effluent presented low content of dry mater and ashes at surfaceor bottom (0.13% on 0-60 cm and 0.17% on deeper than 60 cm), nutrients werelow, pH slightly alkaline, and electric conductivity was a little bit lowerthan the critical value 2dS/m. Sodium (406.5 mg/L) and nitrogen (about 100mg/L) were in high concentration, but phosphorus was very low (5.9 mg/L).Content of Ca, Mg, and K was 97.5, 25, and 107.5 mg/L, respectively, and increasedwith depth. Levels of BOD and COD indicated the water was slightly contaminated(20.6 mg O2/L) and under levels of industrial effluents (24.8 mg O2/L).Microbiological analysis did not register Salmonella,but Escherichia coli was present,also we found total anaerobics, and coliforms. Based on results a possible useis for agriculture, production of trees, or species used to feed livestock. Forevery option amount of pathogens must be determinate and if they exceedregulated values they should be reduced.