Silage of Prickly Pears (Opuntia spp.) Juice By-Products
Department of Veterinary Medicine and Animal Production, University of Federico II, via Federico Delpino 1, 80137 Napoli, Italy
Azienda Sanitaria Provinciale Agrigento Viale della Vittoria, 321-92100 Agrigento, Italy
Department of Agricultural, Food and Forest Science (SAAF), University of Palermo, Viale delle Scienze 13, 93011 Palermo, Italy
Author to whom correspondence should be addressed.
Received: 13 August 2020 / Revised: 17 September 2020 / Accepted: 18 September 2020 / Published: 22 September 2020
The cactus pear plant is a Cactaceae which originates from the Americas and is highly resistant to arid and hot environments. The plant is used as animal feedstuff in regions characterized by a lack of nutrient resources. In Italy, the fruits are known as prickly pears are usually eaten fresh by humans, and more recently have also started to be transformed into fruit juice. Various by-products (i.e., peel, pulp, and seeds) derived from the extraction of fruit juice are used for livestock feed due to their high amounts of fermentable structural carbohydrates. However, some of these by-products are difficult to conserve due to their high fermentability. The aim of the present study was to produce micro-silages of prickly pear by-products with different level of wheat straw (0, 5, and 10% as fed) and evaluate their chemical characteristics and fermentation kinetics using the in vitro gas production technique. Both chemical parameters (higher crude protein and lower neutral detergent fibre) and in vitro fermentation data demonstrated that the silage obtained with 5% of straw as the best-preserved (lower pH and ammonia nitrogen concentration).