Compost inclusion level in soil on chemical composition and in vitro dry matter digestibility of native and improved cactus forage varieties

• Published in: Journal of animal science 2016-10, Vol.94, p.307-307
• Main Authors: Santos-Haliscak, J A, Kawas, J, Durazo, H Fimbres, Moreno-Degollado, G, Vázquez-Alvarado, R E, Olivares-Sáenz, E, Andrade-Montemayor, H
• Format: Article
• Language: English
• Subjects: Ashes; Beds; Cactus; Calcium; Chemical composition; Composting; Composts; Digestibility; Dry matter; Flux density; Hemicellulose; Hydroxyapatite; Iron; Lignin; Livestock; Livestock feeds; Manganese; Moisture content; Nitrogen; Phosphorus; Proteins; Soil chemistry; Soil moisture; Studies; Water content; Zinc
• ISSN: 0021-8812; 1525-3163
• DOI: 10.2527/jam2016-0643

The objective of this study was to determine DM and protein production per hectare, chemical composition, and in vitro digestibility of two cactus varieties planted in soil with three compost levels. A randomized complete block design with a factorial arrangement of treatments, with the two cactus varieties, one with spines (WS) and one without spines (WOS), four seasons (summer, fall, and winter of 2013 and spring 2014) and three levels of compost (0, 61, and 122 tons/ha) was conducted. Compost was purchased from a local feedlot. The WS variety was Forrajero Mina and the WOS was COPENA F1. These were planted in double rows, with a spacing of 0.5 m between plants and 0.6 m between rows in 1.2-m-wide beds. The design included 5 beds (repetitions), for a total of 300 plants per variety and 600 for the entire experiment. The WS variety had higher concentrations of NDF (30.5 vs. 22.3%; P = 0.001), hemicellulose (17.5 vs. 7.9%; P = 0.001), ash in NDF (4.09 vs. 3.14%; P = 0.005), iron (59.8 vs. 49.8 ppm; P = 0.020), and manganese (41.1 vs. 34.3 ppm; P = 0.005), whereas the WOS variety had higher concentrations of lignin (1.4 vs. 0.7%; P = 0.001), ash in ADF (0.92 vs. 0.45%; P = 0.03), calcium (3.1 vs. 2.9%; P = 0.001), and zinc (44.6 vs. 39.0 ppm; P = 0.03). In vitro DM digestibility was higher (79 vs. 67%; P = 0.001) for the WOS variety. The inclusion of compost increased DM (2.8 to 4.4 tons/ha; P = 0.018) and CP (196 to 556 kg/ha; P = 0.001) production, lignin (0.83 to 1.22%; P = 0.008), phosphorus (0.10 to 0.23%; P = 0.001), and zinc (36.7 to 44.1 ppm; P = 0.025) while decreasing the concentration of ash in ADF (0.93 to 0.51%; P = 0.031). The two cactus varieties had high ash and moisture content, which may reduce the energy density of this feed for livestock. Nitrogen associated with the ADF fraction (0.65%) may reduce nitrogen availability for bacteria in the rumen.