EFFECT OF ACID STRESS ON THE EMBRYONIC-DEVELOPMENT OF THE COMMON CARP (CYPRINUS-CARPIO)

Sensitivity of eggs and sac fry of the common carp (Cyprinus carpio) to pH levels in the range of 4.5 to 7.5 was assessed up to 117 h after fertilization. Studied parameters were rate of embryonic development, time and duration of hatching, and spinal cord deformation. In the pH range between 4.75 and 5.2 egg mortality was highest and a delay in the rate of embryonic development and hatching was observed in the surviving embryos. A strong increase of spinal cord deformation of sac fry occurred in the lower pH ranges (pH 5.5-4.75). Common carp appeared to be more sensitive to acid stress than many other species of fish.