Mitigating the impact of winter temperatures on striped catfish (Pangasianodon hypophthalmus) using functional feed additives

The drop in temperature during the winter months can lead to a decrease in growth, induce metabolic stress, and increase mortality incidences. The present study evaluated the potential of functional feed additives in mitigating the negative impacts of winter-rearing conditions in striped catfish (Pangasianodon hypophthalmus). Four test diets were evaluated over a twelve-week feed trial: (1) zinc-acetate (Zn-acetate), (2) selenomethionine (Se-Met), (3) β-glucan, and (4) control with no added feed additive. The survival rate in the β-glucan (95.00%) and Zn-acetate (93.30%) dietary groups was higher than the control (78.30%) and Se-Met (85.00%). Fish fed with the β-glucan had the highest weight gain (20.75% increase), specific growth rate (13.75% increase), and lower feed conversion ratio (9.64 % decrease). However, feed additives did not influence the fatty acid profiles or whole-body proximate composition. Although, Zn-acetate and Se-Met had higher body ash content. Serum cortisol and glucose levels were lower in β-glucan and Zn-acetate than in other treatment groups. All feed additives resulted in higher superoxide dismutase, glutathione peroxidase, and catalase activity in the liver and muscle. This study found that β-glucan and zinc-acetate can improve cold stress resistance and offer a sustainable strategy for catfish rearing over winter.