PSIX-42 Comparasion of cactus (Opuntia ficus-indica) digestion kinetics with alfafa (Medicago sativa) and orchard (Dactylis glomerata) hays

Abstract

Abstract Opuntia ficus-indica is highly regarded as an emergency feed for livestock during drought and as a mainstay for the wildlife population in temperate semi-arid and arid parts of the United States. The goal of this study was to assess the effects of replacing alfalfa and orchard grass with different levels of prickly pear on digestion and fermentation patterns. Three forages were evaluated: alfalfa, orchard grass and prickly pear. In order to determine kinetics of digestion, gas volumes were measured after incubation periods of 0, 3, 6, 12, and 24 h. Samples were run in triplicate with 2 blanks for a total of three periods. Data on gas production were fitted to the equation by Ørskov and McDonald (1979) using SAS software 9.4 (P ≤ 0.05; SAS Inst. Inc., Cary, NC) program. The gas volume observed from the soluble fraction ‘a’ and ‘b’ were similar (P > 0.05) for prickly pear amongst all treatments; no difference was observed between alfalfa and cactus. The rate of gas production ‘c’ was higher in cactus (16.5%, h-1) than alfalfa and orchard grass (11.5%, h-1 and 7.7%, h-1, respectively). The extent ‘a +b’ of gas volumes revealed no difference among the test forages. Prickly pear showed a faster rate of degradation compared to alfalfa and orchard grass. A rapid rate of digestion means a faster passage of the material through the digestive tract. Thus, the higher values obtained for the ‘c’ and similar ‘a + b’ parameters in prickly pear compared to alfalfa or orchard grass, may signal it as a good potential alternative feed in arid and semi-arid areas.