Effect of storage time of multiple-nutrient blocks on intake and digestibility of prairie hay by sheeps

Abstract

Twelve intact male African hair sheep (4 mo of age and 16 kg liveweight) were used to compare the digestibilities of three diets: T1 (control), Brachiaria humidicola hay ad libitum; (T2), hay plus a multinutrient block (MB) stored for 15 d; T3, hay plus aMB stored for 45 d. The sole formula (%) of the MB’s was: cane molasses, 40.0%; corn meal, 26.75%; ground limestone, 10.0%; salt, 10.0%; mineral supplement, 8.0%; urea, 5.0%; and sulfur, 0.25%. Following 12 d to accustom the animals to metabolism stalls, feces and urine were collected for 6 d. Daily dry matter (DM) intake from hay increased from 697 g in T1 to 700 g in T2 (P<.05) and 657 g in T3 (P>.05), while corresponding increases in totalDM(P<.05) were to 902 and 834 g in T2 and T3.DM digestibility of T1 was lowest (49.8%), that of T2 highest (69.9%) and that of T3 intermediate (63.4%), all three differing (P<.05); the same was true of crude protein digestibility (62.9, 75.6 and 72.0% for T1, T2, and T3). DM digestibility of the MB, determined by difference, was 141% and 110% for T2 and T3, indicating positive associative effects of MB on digestion of the hay. Daily nitrogen retention in the body was 39.9, 68.4 and 62.7 g in T1, T2, and T3, with three differences (P<.05). The fresher MB gave better results, but the MB stored for a longer period retained a large part of its effectiveness to improve the diet based on prairie hay.