Development of a novel rumen-protected lysine delivery system using beeswax and carnauba wax lipid matrices combined with natural tannins for ruminant nutrition

Abstract

Incorporating bypass protein into ruminant diets is essential for delivering intact essential amino acids, such as lysine, to the small intestine, thereby improving nutrient absorption, animal growth, milk yield, and overall health. This strategy contributes to more efficient and sustainable livestock production. This study investigated the use of beeswax (BW) and carnauba wax (CW) lipid matrices to microencapsulate lysine (Lys) for targeted post-ruminal delivery, with additional protection provided by tannins extracted from Mimosa tenuiflora hay. A completely randomized experiment was designed in a 2 × 4 factorial arrangement for lysine protection, with two types of encapsulants (shell), BW and CW for Lys protection (core), with a shell-to-core ratio of 2:1 and four levels of tannin, i.e., 0; 1; 2; 3% inclusion based on the dry matter of the wax mass as the adjuvant to the material, totaling eight experimental treatments, including BWLys_0%; BWLys_1%; BWLys_2%; and BWLys_3% and CWLys_0%; CWLys_1%; CWLys_2%; and CWLys_3%. The preparation of microencapsulated Lys as a bypass protein source was carried out fusion-emulsification method. The evaluation of the material showed that the microencapsulation yield improved with the inclusion of tannin, ranging from 75 to 79% for bypass Lys microencapsulated in BWLys_0% and BWLys_3%, and from 80 to 84.5% for bypass Lys microencapsulated in CWLys_0% and CWLys_3%, respectively. The microencapsulation efficiency also improved with the addition of tannin, ranging from 81 to 85% for BWLys_0% and BWLys_3% and from 79 to 89% for CWLys_0% and CWLys_3%. Among all formulations, the 3% CW treatment (CWLys_3%) exhibited the most effective Lys retention and the highest resistance to ruminal degradation. The findings confirmed the potential of lipid-based encapsulation, particularly when combined with tannins, to protect amino acids and improve their bioavailability for small ruminants.