Black Soldier Fly Larvae Meal in Extruded Diets for Giant Anteaters ( Myrmecophaga tridactyla ): Effects on Digestibility and Physiological Responses

Nutritional management of giant anteaters (Myrmecophaga tridactyla) under human care remains challenging due to their highly specialised insectivorous diet and the limited knowledge of their nutritional requirements. The development of adequate diets is therefore essential for the success of ex situ conservation programmes. This study evaluated the nutritional potential of increasing inclusion levels of defatted black soldier fly larvae meal (Hermetia illucens) in extruded diets for giant anteaters. Four adult females were assigned to a 4 × 4 Latin square design and fed diets containing 0%, 18%, 36%, or 54% insect meal. Feed intake, apparent nutrient digestibility, faecal score, and haematological and biochemical parameters were evaluated. No significant effects of treatment were observed on feed and water intake, faecal output, or apparent digestibility coefficients of the main nutrients (p > 0.05). Digestibility values were high across all treatments, indicating good adaptation of the species to extruded diets containing insect-derived ingredients. Most haematological and biochemical parameters remained within reference ranges. However, higher inclusion levels of insect meal were associated with reduced total plasma protein and coagulation-related proteins (p < 0.05), likely due to overestimation of crude protein content associated with chitin. An increase in relative eosinophil counts was also observed at higher inclusion levels (p < 0.05). These results demonstrate that black soldier fly larvae meal can be included in extruded diets for giant anteaters without impairing nutrient utilisation or overall metabolic health. However, accurate protein evaluation is required when formulating insect-based diets. The use of such ingredients represents a promising strategy to improve nutritional management and support conservation programmes for this species.