Dietary arginine and repeated handling increase disease resistance and modulate innate immune mechanisms of Senegalese sole (Solea senegalensis Kaup, 1858)

10 páginas, 4 figuras, 4 tablas

Stress is known to impair immune function and disease resistance in fish. In the present study, repeated handling was employed as a chronic stressor in order to verify whether its attributed immunosuppressive effects could be minimized by dietary arginine supplementation. Therefore, Senegalese sole (Solea senegalensis) were air exposed daily for 3 min during 14 days (handling) or left undisturbed (control). In addition, both control and handled specimens were fed 3 diets with graded levels of arginine (Arg 4.4, Arg 5.7 and Arg 6.9 g 16 g 1 N). Following the 14 days stress challenge and feeding on those diets, fish were infected with Photobacterium damselae subsp. piscicida (strain PC566.1; LD50 5 103 cfu mL 1) and fed the same experimental diets. Respiratory burst activity and nitric oxide production of headekidney leucocytes increased parallel to dietary arginine supplementation. HIF-1, HAMP-1, MIP1-alpha and gLYS expression values and some humoral parameters augmented in control specimens fed the Arg 5.7 and Arg 6.9 diets. Interestingly, repeated acute stress increased both disease resistance and some innate immune mechanisms in handled fish. The role of dietary arginine and repeated handling on Senegalese sole innate immunity and disease resistance are discussed.

This study was partially supported by project CSD2007-00002 Aquagenomics funded by the program Consolider-Ingenio 2010 from the SpanishMinisterio de Ciencia e Innovación. SPAROS participation in this study had the support of project ANYFISH, co-funded by PO Algarve 21, QREN and FEDER (European Union). Benjamín Costas benefited from grant by Fundação para a Ciência e a Tecnologia, Portugal (SFRH/BD/38697/2007).

Peer reviewed