Feed value evolution of whole discarded fruits and peels of two Moroccan Opuntia ficus-indica Mill. accessions

The use of crop and agro-industrial by-products in animal feeding is an alternative to fill the fodder deficit in low rainfall areas. The aim of the present study was to investigate the chemical composition and the in vitro dry matter digestibility (IVDMD) of whole discarded cactus fruits (WDCF) and their fruit peels (FP) for two accessions (spiny and spineless) during the three months when they are available. Forty samples were harvested from each accession once a month from an eight-year-old field. Each sample composed of ten WDCF. The results showed a significant effect (p<0.05) of the accession and the month for most studied parameters. For the three months combined, the average proportion of peel to whole fruit (FP/WDCF) was highest for the spiny accession compared to the spineless accession (50.4 vs. 46.1% dry matter (DM)). During the harvesting periods and for the two accessions, the DM averaged 16.9 and 16.3%; crude protein (CP) were 5.3 and 3.9% DM, respectively, for WDCF and FP. The neutral detergent fiber (NDF) was 24.9 and 11.5%; IVDMD was 77.7 and 90.7%; while the phosphorus (P) content was 0.09 and 0.07%, respectively, for WDCF and FP. With the harvesting period, for both products and the two accessions, the DM, Ash, CP and IVDMD decreased, while the three fiber components (NDF, ADF and ADL) increased. The nutritive value of the spiny accession collected in September had the highest value. Both WDCF and FP are supplementing the diets of ruminant cereal straw, while ensuring adequate protein and fiber in diets.