Microplastic Exposure Disrupts Energy Homeostasis and Welfare in Goldfish

Area of Science:

• Environmental toxicology
• Aquatic ecology
• Fish physiology

Background:

• Microplastic pollution is a growing concern in aquatic environments.
• Fish welfare and energy balance are crucial for ecosystem health.
• Polystyrene microplastics are common environmental contaminants.

Purpose of the Study:

• To investigate the impact of polystyrene microplastics on goldfish energy balance and welfare.
• To assess behavioral, metabolic, neuroendocrine, and physiological responses to microplastic exposure.
• To understand the mechanisms underlying microplastic-induced disruptions in fish.

Main Methods:

• Goldfish (Carassius auratus) were exposed to 15 µm virgin polystyrene microplastics for 14 days.
• Integrated analysis of behavioral changes, feed intake, and metabolic rate (oxygen consumption).
• Neuroendocrine gene expression (orexigenic and anorexigenic pathways) and physiological stress markers (plasma cortisol) were measured.

Main Results:

• Microplastic exposure significantly reduced feed intake and feed anticipatory activity (anorexigenic effect).
• Neuroendocrine disruption observed with altered expression of appetite-regulating genes.
• Increased oxygen consumption, impaired growth, reduced hepatosomatic index, and elevated cortisol levels indicated metabolic stress and anxiety-like behavior.

Conclusions:

• Polystyrene microplastics disrupt energy homeostasis in goldfish.
• Microplastic exposure triggers neuroendocrine and physiological stress responses, compromising fish welfare.
• These disruptions impact the biological resilience of aquatic species to pollution.