ABSTRACT
The main objective of the present study was to evaluate the effects of the dietary addition of different levels of rosemary powder (RP) and vitamin E (VitE) on broiler performance and gut gross morphometry. A total of 270 one-day-old Ross 308 male chicks were randomly assigned to nine dietary treatments with three replicates of10 birds each. Treatments consisted of diets were supplemented with 0, 0.5 or 1.0% RP and 0, 100 or 200 mg/kg VitE (alpha-tocopherol acetate). Feed intake and weight gain were recorded weekly. On day 42, one bird per replicate was euthanized after blood sampling. Gastrointestinal tract segments were measured and/or weighed. Means were compared by least significant difference. Overall, broilers fed1.0% RP presented lower (p< 0.05) feed intake, weight gain, and final weight body than those fed 0.5% RP. Broilers fed the 0.5% RP plus 200 mg/kg VitE diet presented higher weight gain (p<0.05) in than those in the control group (0% RP and 0 mg VitE). Jejunum length and weight, colon length and width, and right cecum weight were also negatively affected (p<0.05) by the 1.0% RP diet when compared with the 0.5% RP diet. We suggest that the dietary supplementation of 0.5% RP plus 200mg/kg of vitE improves broiler performance and does not have significant adverse effects on gross gut morphometry. Dietary VitE may play a potential protective role against the negative effects of high levels of RP.
Keywords:
Gut; nutrition; rosemary; vitamin E; weight gain.