The modulatory impact of Arabic gum and lecithin on the efficiency of cold-stressed Nile tilapia (Oreochromis niloticus)

Abstract

Tilapia are commonly used in aquaculture but are sensitive to cold, limiting their culture in colder regions. Thus, the purpose of this investigation was to examine how lecithin and/or Arabic gum could help Nile tilapia cope with cold stress during the winter season. In a 3×3 factorial feeding study, tilapia fingerlings with an average initial weight of 7.56 ± 0.10 g were given nine different diets (crude protein: 305 g kg⁻¹; gross energy: 19.47 MJ kg⁻¹) for 60 days during the winter. The diet formulations included three levels of Arabic gum (0 g, 2 g, and 4 g kg⁻¹), with each level receiving three different dosages of lecithin (0 g, 5 g, and 10 g kg⁻¹). After the trial, tilapia fed the food enriched with 4 g kg⁻¹ Arabic gum and 10 g kg⁻¹ lecithin showed the highest specific growth rate, fish survival, weight gain, and the lowest feed conversion ratio. Low-density lipoprotein cholesterol and cholesterol levels were highest in fish given the control diet. The groups fed diets with 10 g kg⁻¹ lecithin and 4 g kg⁻¹ Arabic gum showed higher levels of triglycerides and HDL-C. Significant decreases in alanine aminotransferase, glucose, aspartate aminotransferase, and cortisol activities were also observed (P < 0.05) with the same diet. Fish fed a diet enriched with 4 g kg⁻¹ Arabic gum and 10 g kg⁻¹ lecithin showed the highest levels of serum calcium, potassium, sodium, and chlorine, as well as the highest transcription of Δ9D. The same diet was shown to have the lowest levels of malondialdehyde and the highest activity levels for other antioxidant enzymes such as glutathione peroxides, superoxide dismutase, glutathione, catalase, and total antioxidant capacity. Tilapia raised in cold-stressed winter conditions had improved survival and performance when fed a diet containing 4 g kg⁻¹ of Arabic gum and 10 g kg⁻¹ of lecithin.