Casca de tucumã (Astrocaryum aculeatum G. Mey) na alimentação de vacas leiteiras

Abstract

Milk production in the Amazonas region faces challenges related to forage seasonality and high feed costs, highlighting the need for sustainable alternatives for animal feeding. In this context, the present study aimed to evaluate the effects of including tucumã peel (Astrocaryum aculeatum G. Mey) as a substitute for BRS Capiaçu elephant grass in the diet of dairy cows on ingestive behavior, nutrient intake, apparent digestibility, milk yield, milk composition, and milk fatty acid profile. Lactating Jersey cows were assigned to a 4 × 4 Latin square design and fed diets containing 0, 5, 10, and 15% tucumã peel inclusion. The inclusion of this agro-industrial by-product did not impair ingestive behavior, dry matter intake, or nutrient digestibility, indicating the maintenance of nutritional efficiency and ruminal function. Milk yield and chemical composition remained unchanged, demonstrating that productive performance was maintained across all inclusion levels. Regarding the milk fatty acid profile, a significant linear decrease was observed for palmitic (C16:0), tricosanoic (C23:0), and lignoceric (C24:0) acids, whereas oleic acid (C18:1 cis-9) increased linearly with tucumã peel inclusion. Additionally, a reduction in the atherogenicity index and an increase in the hypocholesterolemic-to-hypercholesterolemic fatty acid ratio (h/H) were observed, indicating improvements in the nutritional quality of milk fat and potential benefits for human health. The reduction in palmitic acid associated with the increase in oleic acid suggests the production of milk with lower atherogenic potential and a more favorable lipid profile for cholesterol metabolism. It is concluded that the inclusion of up to 15% tucumã peel in the diet of dairy cows is a promising alternative for Amazonian dairy production systems, as it maintains animal productive performance, adds value to a regional agro-industrial by-product, and improves the nutritional quality of the milk produced.