Table of Contents (continued) 



Host-Parasite relationship 2U 



Incubation period 2\\ 



Change in virulence during an epizootic 2h 



Species specificity 27 



Age specificity 27 



Size specificity 28 



Organ specificity 28 



Effect of water temperatures 28 



Nutritional effect 28 



Immunity in recovered fish 30 



Effect of chemotherapy 30 



Effect of crowding 30 



Spread of the disease in the hatchery 30 



Discussion and Conclusion 30 



Etiology 30 



Source of the virus 31 



Control of the disease 33 



Acknowledgments 35 



Literature cited „ . 36 



