Effect of ultraviolet radiation on the immune response of Broad-snouted caiman (Caiman latirostris) injected with LPS from Escherichia coli

FERNÁNDEZ, LUCÍA; POLETTA, GISELA L.; AMAVET, PATRICIA S.; SIROSKI, PABLO A.

Lake Charles, Louisiana

Congreso; 23rd Working Meeting of the Crocodile Specialist Group (SSC-IUCN); 2014

Crocodile Specialist Group and McNease State University

Ultraviolet radiation (frequencies A and B) is necessary in many vital processes and all organisms have a dependence on it, directly or indirectly. In natural conditions, quantity and quality of UV radiation received by organisms depends on numerous factors. Under artificial conditions, it is possible to provide and regulate UV exposure, but an overexposure might induce adverse effects such as immune suppression. This may debilitate the recognition of some antigens even few days after the irradiation, with serious consequences on both animals and human health. Lipopolysaccharide (LPS) is a major component of the outer membrane of Gram negative bacteria and contains a toxic substance (Lipid A) that is recognized by the immune systems of higher eukaryotes, causing an inflammatory reaction. In this case, LPS was used to challenge an immune response in C. latirostris. Caimans of 3 months were maintained under different treatments of UVR intensities during ninety-five days and then injected with LPS or saline solution. Animal growth (weight, total and snout vent length), as well as immune response was evaluated. The results showed that immune parameters, as complement system, was only affected by the high intensities of UV exposure (p < 0,01) while growth of the animals was not affected by UVR exposure (p>0,05).