Effect of glycerine and essential oils (anacardium occidentale and ricinus communis) on animal performance, feed efficiency and carcass characteristics of crossbred bulls finished in a feedlot system

Abstract

The effect of corn substitution by glycerine and essential oils on animal performance, apparent digestibility and red and white blood cells of crossbred bulls finished in feedlot was evaluated. Thirty bulls with average weight of 311±28.8 kg and 22±2 month-old were allocated in three diets: CON (without glycerine or essential oils), GLY (with glycerine) and GEO (with glycerine and essential oils). The bulls were fed a diet of sorghum silage, cracked corn, soybean meal, urea, limestone and mineral salt. Three grams of cashew and castor oil/animal/day were included in GEO diet. Animals were kept in feedlot for 115 days and slaughtered at average weight of 467±40.6 kg. No differences (P<0.05) among diets regarding final body weight, average daily gain and feed conversion were reported. Ether extract intake was higher (P<0.05) in CON diet compared to the others. Dry matter, organic matter and crude protein digestibility was higher (P<0.05) in GLY diet compared to CON. Acid detergent fibre digestibility was higher (P<0.05) in CON compared to GLY diet. Nonfibrous carbohydrate, fibrous carbohydrate and ether extract digestibility were similar (P>0.05) among diets. No effect of glycerine and essential oil addition on total blood cholesterol, triglycerides, haemogram, leukogram and plasmatic proteins was observed. Corn replacement by glycerine and essential oils addition did not affect (P>0.05) carcass weight, dressing and conformation, carcass length and cushion thickness.