Ingestive Behavior of Heifers Feeding with Marandu Grass Silage

The present study was aimed at assessing the ingestive behavior of ¾ Zebu × Holstein heifers confined to different levels of substitution of sorghum silage by marandu grass silage. Twenty heifers were used with initial average weight of 346.25 kg, divided into completely randomized experimental design with 5 repetitions and the following treatments: treatment 1) roughage fraction of the diet composed of 100% of sorghum silage; treatment 2) roughage fraction of the diet composed of 70% of sorghum silage and 30% of marandu grass silage; treatment 3) roughage fraction of the diet composed of 30% of sorghum silage and 70% of marandu grass silage and treatment 4) roughage fraction of the diet composed of 100% of marandu grass silage. Concentrate was provided (25.25% soybean meal, 73.44% ground corn and 1.31% mineral mixture, based on natural matter), made calculations for ingestion of 1.2% of the live weight. Visual observations were accomplished for determination of ingestive behavior, every 21 days. The substitution of sorghum silage by marandu grass silage increased time with feeding, it did not affect time with rumination, time of chew, number of chews a day nor number of meals a day, but it resulted in lower feed efficiency, without interfering in the rumination efficiency of dry matter (DM) and neutral detergent insoluble fiber (NDF).