Abstract
The accumulation of ammonia in fish ponds regularly occurs in intensive aquaculture systems, and the inclusion of yucca extract is recognized as a practical solution to adsorb the waterborne ammonia. In this context, the study was planned to investigate the possible regulatory roles of yucca extract on the performances of common carp exposed to acute ammonia stress. Fish with similar initial weight were assigned to four groups (triplicates) where fish in the control group reared without ammonia exposure and without yucca treatment whereas the second group was exposed to ammonia (10 mg/L) without yucca treatment. The third group treated with yucca (0.75 mg/L) without ammonia while the fourth group exposed with ammonia and treated with yucca. The groups were named as the control, the ammonia, the yucca, and the ammonia/yucca. After 30 days, the growth performance, survival rate, total protein, albumin, and globulin of fish treated with yucca extract had the highest values (P < 0.05) followed by control and those exposed to acute ammonia stress and treated with yucca. The feed conversion ratio (FCR) displayed the lowest value in fish treated with yucca without ammonia stress while the highest FCR was in fish exposed to ammonia without yucca (P < 0.05). The uric acid and urea levels displayed the lowest value in fish treated with yucca without ammonia stress while the highest uric acid and urea were in fish exposed to ammonia without yucca (P < 0.05). The levels of blood creatinine, aspartate aminotransferase (AST), alkaline phosphatase (ALP), and alanine aminotransferase (ALT) implemented the highest values in fish exposed to acute ammonia stress without yucca while the lowest values were in the group of fish treated with yucca without ammonia exposure (P < 0.05). The expression of hepatic catalase (CAT), superoxide dismutase (SOD), and interleukin (IL-10) genes were upregulated in fish treated with yucca and downregulated in fish exposed to acute ammonia stress. Heat shock protein (HSP70), interleukin (IL-8), tumor necrosis factor-alpha (TNF-α), interferon gamma (IFN-γ), and interleukin (IL-1β) were upregulated in fish exposed to acute ammonia stress and downregulated in the group of fish treated with yucca extract (P < 0.05). The histopathological study revealed that fish exposed to acute ammonia stress had inflammatory and abnormal features while yucca extract induced anti-inflammation influences. Hence, the study concluded that the treatment of yucca extract is recommended to protect common carp from the toxicity of waterborne ammonia.
•Common carp exposed with waterborne ammonia for 30 days and treated with or without yucca.•Fish treated with yucca had higher growth and survival rates than those exposed to ammonia.•Fish exposed with acute ammonia displayed impaired hepato-renal function, antioxidative capacity, and immunity.•Yucca extract regulated the pro-inflammatory and anti-inflammatory genes of fish stressed with ammonia.•The histopathological study revealed abnormal features under ammonia exposure, but fish treated with yucca showed normal features.