Influence of oregano extract on the intestine, some plasma parameters and growth performance in chickens

The effect of oregano essential oil on growth performance, intestinal alkaline phosphatase (IAP) level, enterocyte proliferative ability, plasma proteins, and plasma minerals (calcium and magnesium) were studied in 1 day-old Ross 308 hybrid broiler chickens under commercial conditions during 42 experiment. Chickens fed oregano oil supplemented diet (0.707 g/kg) had significantly higher body weight gain (BWG) in the grower (19-29 d) and finisher (30-42 d) periods. Total plasma immunoglobulin levels were lower while mineral levels were higher during the finisher period. Significant decrease of IAP activity was demonstrated in animals fed oregano oil supplemented diet on 29, and 42 days of the experiment. Proliferative activity of enterocytes significantly increased in the finisher period along duodenal villi in animals treated with essential oil extracted from oregano. We suppose that higher body performance was probably the result of higher digestibility in the digestive tract. It is suggested that the antibacterial effect of carvacrol caused a lower number of intestinal bacteria, decrease of immunoglobulins and increase of investigated plasma proteins.