Publication Date:
2024-03-15
Description:
Acidification (OA), a global threat to the world's oceans, is projected to significantly grow if CO2 continues to be emitted into the atmosphere at high levels. This will result in a slight decrease in pH. Since the latter is a logarithmic scale of acidity, the higher acidic seawater is expected to have a tremendous impact on marine living resources in the long-term. An 8-week laboratory experiment was designed to assess the impact of the projected pH in 2100 and beyond on fish survival, health, growth, and fish meat quality. Two projected scenarios were simulated with the control treatment, in triplicates. The control treatment had a pH of 8.10, corresponding to a pCO2 of 321.37 ± 11.48 µatm. The two projected scenarios, named Predict_A and Predict_B, had pH values of 7.80-pCO2 = 749.12 ± 27.03 and 7.40-pCO2 = 321.37 ± 11.48 µatm, respectively. The experiment was preceded by 2 weeks of acclimation. After the acclimation, 20 juvenile black sea breams (Acanthopagrus schlegelii) of 2.72 ± 0.01 g were used per tank. This species has been selected mainly due to its very high resistance to diseases and environmental changes, assuming that a weaker fish resistance will also be susceptibly affected. In all tanks, the fish were fed with the same commercial diet. The seawater's physicochemical parameters were measured daily. Fish samples were subjected to physiological, histological, and biochemical analyses. Fish growth, feeding efficiency, protein efficiency ratio, and crude protein content were significantly decreased with a lower pH. Scanning electron microscopy revealed multiple atrophies of microvilli throughout the small intestine's brush border in samples from Predict_A and Predict_B. This significantly reduced nutrient absorption, resulting in significantly lower feed efficiency, lower fish growth, and lower meat quality. As a result of an elevated pCO2 in seawater, the fish eat more than normal but grow less than normal. Liver observation showed blood congestion, hemorrhage, necrosis, vacuolation of hepatocytes, and an increased number of Kupffer cells, which characterize liver damage. Transmission electron microscopy revealed an elongated and angular shape of the mitochondrion in the liver cell, with an abundance of peroxisomes, symptomatic of metabolic acidosis.
Keywords:
Acanthopagrus schlegelii; Alkalinity, total; Alkalinity, total, standard deviation; Animalia; Aragonite saturation state; Aragonite saturation state, standard deviation; Behaviour; Bicarbonate ion; Bicarbonate ion, standard deviation; Calcite saturation state; Calcite saturation state, standard deviation; Calculated using CO2calc; Calculated using seacarb after Nisumaa et al. (2010); Carbon, inorganic, dissolved; Carbon, inorganic, dissolved, standard deviation; Carbonate ion; Carbonate ion, standard deviation; Carbonate system computation flag; Carbon dioxide; Category; Chordata; Coast and continental shelf; Condition factor; Condition factor, standard deviation; Containers and aquaria (20-1000 L or 〈 1 m**2); Feed conversion efficiency; Feed conversion efficiency, standard deviation; Feed conversion ratio; Feed conversion ratio, standard deviation; Feed intake; Feed intake, standard deviation; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Gain; Gain, standard deviation; Growth/Morphology; Hepatosomatic index; Hepatosomatic index, standard deviation; Laboratory experiment; Mass; Mass, standard deviation; Mortality/Survival; Nekton; North Pacific; OA-ICC; Ocean Acidification International Coordination Centre; Other studied parameter or process; Partial pressure of carbon dioxide, standard deviation; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Pelagos; pH; pH, standard deviation; Potentiometric; Potentiometric titration; Protein efficiency ratio; Protein efficiency ratio, standard deviation; Proximate composition; Proximate composition, standard deviation; Registration number of species; Salinity; Salinity, standard deviation; Single species; Species; Specific growth rate; Specific growth rate, standard deviation; Survival; Survival rate, standard deviation; Temperate; Temperature, water; Temperature, water, standard deviation; Treatment; Type; Uniform resource locator/link to reference
Type:
Dataset
Format:
text/tab-separated-values, 651 data points
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