Armazenamento pós-colheita afeta a digestibilidade in vitro e a produção de gases de cladódios de cultivares de palma forrageira?

Abstract

The forage cactus plays a fundamental role in animal feed, especially during drought periods in Northeastern Brazil. However, the cultivation and use of this forage require significant labor investment throughout the entire process, from planting to harvesting and daily transport for animal feeding. This study hypothesized that post-harvest storage of the forage cactus cultivars ‘Orelha de Elefante Mexicana’ (Opuntia stricta [Haw.] Haw.) and ‘Miuda’ (Opuntia cochenillifera (L.) Mill), for up to 56 days, may interfere by reducing the digestibility levels and gas production of the forage. The objective was to evaluate the effect of different post-harvest storage times on the in vitro digestibility and in vitro total gas production parameters of the forage cactus cultivars ‘Orelha de Elefante Mexicana’ and ‘Miuda’. The experiment was conducted at the Experimental Farm of the Federal Rural University of Pernambuco (UFRPE) Prof. Antônio de Pádua Maranhão Fernandes, located in Garanhuns - PE, Brazil. The forage cactus used was obtained from a one-year-old cactus plantation established on the farm, preserving the mother cladode during harvest. The experiment was conducted in a completely randomized design, with repeated measures over time and four replicates. Two experiments were carried out, with each cultivar of forage cactus evaluated independently. Eight experimental treatments were evaluated: 0, 8, 16, 24, 32, 40, 48, and 56 days of post-harvest storage. During storage, the aim was to maintain the cladodes without damage throughout the experimental period, with storage taking place in a covered warehouse open on the sides. The samples for analysis were composed of cladodes of different orders and from different parts of the piles. The variables evaluated were in vitro Dry Matter Digestibility (IVDMD), Indigestible Neutral Detergent Fiber (iNDF), and in vitro Total Gas Production (TGP). An analysis of variance was performed, using Tukey’s test with a significance level of 5%. The forage from Orelha de Elefante Mexicana showed high IVDMD, being 823.1 g/kg at time 0 (no storage), and an average of 660.2 g/kg from 8 to 56 days post-harvest. For iNDF, high levels were observed for Orelha de Elefante Mexicana as the storage time increased, with the 40 and 56-day post-harvest times being statistically superior to time 0 (no storage). For Miúda, iNDF on days 32, 40, and 48 of post-harvest storage was 43% higher than at time 0 (no storage). For gas production and fiber carbohydrate degradation, values of 251.5 and 153 mL/g DM were observed, respectively. The forage from Miúda presented high IVDMD at times 0 and 8 (738.4 and 726.4 g/kg), and higher gas production at times 0 and 8 (267.7 and 179.9 mL/g DM, respectively). Both forage cactus cultivars can be stored post-harvest for up to 56 days without significant compromise in digestibility levels and gas production.