Mango and Avocado Byproducts as Feed Ingredients and Additives in Ruminant diet

The intensification of food-feed competitions and environmental concerns has driven research into unconventional feed sources for optimizing ruminant feeding. In this study, we explored the potential use of mango peel (MP), mango seed (MS), mango seed coat (MSC), avocado peel (AP), and avocado seed (AS) in two experiments. Experiment 1 evaluated the feed potential of these fruits byproducts by assessing their chemical composition, in vitro true digestibility, gas production, and volatile fatty acid production. In vitro true digestibility was determined using the Ankom DaisyII incubator. Among the various byproducts, MP and AP exhibited higher total phenolic content ranging from 121.50 to 243.69 (mg GAE/g) and antioxidant capacity from 342.92 to 366.63 (mg TE/g), indicating their potential to positively influence the rumen ecosystem. MP, MS, and AS showed higher digestibility (86.4–89.5%), increased gas production, and elevated metabolizable energy (8.41-9.59 MJ/kg DM), while MSC and AP exhibited lower values. Acetate-to-propionate ratio, a key methane indicator, was higher in AS (3.97), MSC (3.76), and MS (3.53), and lower in AP and MP (3.05 and 3.08, mmol/l respectively). Experiment 2 was conducted to assess the effectiveness of incorporating mango and avocado by-products extracts (20 mg) as feed additives, in comparison to alfalfa hay utilized as a control basal diet (200mg DM) across all groups. The findings demonstrated that the AS extract group exhibited the highest 24-hour gas production (47.3 ml/0.2 g DM) when compared to both the control and other extract groups (42.1 to 42.5 ml/0.2 g DM). MP and AP extracts significantly reduced acetate to propionate ratio compared to control and other extracts (P < 0.001). Furthermore, the extract groups exhibited a lower ammonia nitrogen concentration compared to the control. In conclusion, MP, MS, and AS show promising results as feed ingredients. Peel extracts of mango and avocado emerge as feed additives, modulating rumen fermentation parameters effectively.