PSXII-11 Apparent total-tract digestibility of nutrients in beef steers consuming bahiagrass hay treated with calcium oxide. (7th December 2018)

• Record Type: Journal Article
• Authors: Ciriaco, F; Henry, D; Dubeux, J; DiLorenzo, N
• Is Part Of: Journal of animal science. Volume 96(2018)Supplement 3
• Page Start: 427
• Page End: 427
• Publication Date: 2018-12-07
• Subjects: Livestock -- Periodicals; Livestock; Electronic journals; Periodicals; 636.005
• DOI: 10.1093/jas/sky404.935
• Languages: English
• ISSNs: 0021-8812

Abstract

Abstract: To determine the effects of CaO treated bahiagrass hay on apparent total-tract digestibility of nutrients in beef steers, 9 ruminally cannulated Angus crossbred steers (494 ± 145 kg BW) were used in a triplicated 3 x 3 Latin square design. Steers were housed at the University of Florida Feed Efficiency Facility (3 steers/pen), where daily individual intake was recorded via the GrowSafe system. Steers were randomly assigned to 1 of 3 treatments: 1) untreated dry hay (DH); 2) hay treated with 8.9% CaCO3 (DM basis) + water (to 50% DM; CC); or 3) hay treated with 5% CaO (DM basis) + water (to 50% DM; CO). Hay and fecal samples were collected for 4 consecutive d to determine apparent total-tract digestibility of DM, OM, CP, NDF, and ADF. Fecal samples were collected twice daily at 0800 h and 1600 h and were pooled within steer. Indigestible NDF (iNDF) was used as an internal indigestible marker. Concentrations of iNDF in feed and feces were determined by ruminal in situ incubations conducted for 288 h. The statistical model included the fixed effects of treatment, square, and period, and the random effect of animal within square. No treatment differences were observed for total-tract digestibility of DM (P = 0.186), OM (P = 0.169), or CP (P = 0.152); however, there was a treatment effect on NDF (P = 0.034) and ADF (P = 0.003) digestibility. Steers consuming DH had greater NDF (52.3%) and ADF (53.7%) digestibility when compared to CC (45.0% and 42.9%; P = 0.016 and P = 0.002; NDF and ADF, respectively) and CO (45.9% and 42.8%; P = 0.035 and P = 0.002; NDF and ADF respectively) steers. In conclusion, CaO failed to improve the digestibility of bahiagrass hay as indicated by decreased total tract digestibility of fiber fractions. Key Words: