EFEITO ASSOCIATIVO DA MONENSINA SÓDICA À VIRGINIAMICINA E/OU ÓLEOS ESSENCIAIS SOBRE O DESEMPENHO DE NOVILHOS TERMINADOS EM CONFINAMENTO

Abstract

The experiment was developed in Livestock Center (NUPRAN), of Midwest State University, in Guarapuava - PR, with the objective of evaluating the associative effect of monensin sodium on virginiamycin and/or essential oils on performance, nutrient consumption and Dry matter intake, apparent digestibility, ingestive behavior and, the carcass traits of finished bulls in confinement. It was used 32 steers crossbred angus, with average age 12 months and average weight of 376 kg. The animals were divided in four treatments with four replicates: T1 - monensin sodium (MO); T2 - monensin sodium + essential oil (MO+EO); T3 - monensin sodium + virginiamycin (MO+VI); T4 - monensin sodium + essential oil + virginiamycin (MO+EO+VI). The association MO+VI provided an increase in the average daily weight gain (ADG) of 24.44%, 22.35%, 21.10% and 17.31% in the weighings of 42, 63, 84 and 96 days, similar the association of MO+EO+VI that provided improvement of 21.94%, 13.59%, 15.45% and 14.75% respectively in the same weighings. The daily and total carcass gain were higher in the associations MO+VI and MO+EO+VI and provided an average gain of 16.67 kg over MO and MO+EO. In the parameters food efficiency, dry matter intake and nutrients expressed in kg day-1 and percentage of live weight, apparent digestibility, ingestive behavior and some carcass characteristics, no significant differences between treatments were observed. The fat thickness was higher when associated with any of the additives to MO, and the farm weight was higher in the associations containing VI.