Nutritional improvement of cactus fruit scraps with addition of alfalfa or Atriplex halimus, and comparison of two animal feed preservation methods (silage and solar drying)

Abstract

This work aimed to study the effect of adding alfalfa (Medicago sativa L.) and Atriplex halimus L. on biochemical properties, microbial flora, ferment silage and solar-dried cactus fruit scraps. Alfalfa and Atriplex were added to cactus silage to improve nutrient quality. Three mixtures were prepared: M1 based on cactus, M2 based on cactus and alfalfa, and M3 based on cactus and Atriplex. Bran and wheat straw were added to the mixtures to improve the moisture content. After adding alfalfa and Atriplex, the protein content of the pre-ensiling material increased (p < 0.05), reaching 10.63% DM for M1, 16.35% DM for M2, and 17.22% DM for M3. During ensilage, a significant amount of sugar and protein was degraded. All silage treatments achieved stable pH values (M1: 4.35, M2: 4.55, and M3: 4.54). The M2 and M3 treatments had the highest amount of protein. After drying, the protein content of the dried treatments was higher than that of the ensiled treatments (8.05% DM for M1, 14.96% DM for M2, and 15.36% DM for M3). In both storage methods, the microbial population declined. However, silage reduces coliforms, yeasts and moulds more efficiently than solar drying. The drying operation preserves remarkedly the nutritional quality of the mixtures while ensiling reduces the number of undesirable microorganisms.