Comparison of haemocytic parameters among flat oyster Ostrea edulis stocks with different susceptibility to bonamiosis and the Pacific oyster Crassostrea gigas

► Differences in THC, DHC and respiratory burst between oyster species were found. ► Bonamia ostreae affects THC, DHC and respiratory burst of Ostrea edulis. ► No studied parameter explained differences in susceptibility between O. edulis stocks.