| Abstract | Eleven St. Croix ewes (49 ± 8.5 kg initial BW) were used in a crossover design to evaluate effects of restricted drinking water availability on feed intake and digestion. Ewes were housed indoors and fed a 51% concentrate pelleted diet containing 18% CP and 33% NDF at 160% of their calculated ME requirement for maintenance of 44.4 g/kg BW0.75 DMI. Periods were 4 wk, with 3 wk for adaptation and 1 wk for total collection of feces. Ad libitum or baseline water intake by individual ewes was determined for 2 wk before the study (3,761 ± 144 g/d). In each period, 5 or 6 ewes were offered water at 75% of baseline intake for 1 wk and subsequently restricted to 50% (RE), while the other ewes were offered the baseline amount (AL). Some water was refused in wk 4, with intake of 2,442 and 1,688 g/d for AL and RE, respectively (SEM = 171.7). Intake of DM was similar (P = 0.582) between treatments (860 and 811 g/d for AL and RE, respectively). Apparent total tract digestibility of DM (67.2 and 62.1%; SEM = 1.30), OM (68.1 and 63.0%; SEM = 1.30), and NDF (44.3 and 34.0%; SEM = 2.46) were greater (P < 0.05) for RE vs. AL, and CP digestibility tended (P = 0.072) to differ (71.1 and 67.2% for RE and AL, respectively; SEM = 1.16). In conclusion, restricted drinking water availability did not influence intake of a 51% concentrate pelleted diet but increased digestibility, presumably by increasing digesta residence time in the gastrointestinal tract. |
