Feeding propolis or essential oils (cashew and castor) to bulls: performance, digestibility, and blood cell counts

Abstract

Background: in cattle production systems, antibiotics are commonly fed to cattle to prevent diseases, metabolic disorders, and to improve feed efficiency. Considerable effort has been devoted towards developing alternatives to the use of antibiotics. Objective: to evaluate the effect of propolis or cashew and castor oils on animal performance, feed intake, digestibility, and blood cell counts of young bulls. Methods: bulls were kept in a feedlot for 49 days. Starting on the 40th day, feces were sampled for five days to estimate digestibility using indigestible dry matter (DM) as a marker. Bulls were fed a control diet (CON) with sorghum silage (41% DM) and cracked corn, soybean meal, glycerine, limestone, and mineral salt. The propolis-supplemented group (PRO) received 3 g/animal/d in the concentrate. The essential oils-supplemented group (OIL) received 3 g/animal/d (1.5 g cashew oil + 1.5 g castor oil) added to the concentrate. Results: final body weight, average daily gain and feed efficiency were better for bulls fed the OIL diet. Propolis or essential oils had no effect on feed intake and digestibility. There was no effect of propolis or essential oils on blood cell counts. Red blood cell concentration was greater in the last day of the experiment, while the number of white blood cells was lower. Conclusions: dietary addition of propolis did not affect bull performance or feed efficiency. The addition of essential oils improved performance. Feed intake, digestibility, and blood cell counts were similar in all treatments.

Keywords

• antioxidants
• biodiesel
• cattle
• co-products
• feedlot
• plant oils
• aceites de plantas
• antioxidante
• biodiesel
• bovino
• cebadero
• co-productos