Effects of the inclusion of two extracts derived from the olive industry on growth performance, antiparasitic protection, and antioxidant activity in broiler chicken diets from 0 to 45 d

Abstract

The objective of the present study was to investigate the optimal inclusion rate of 2 independent extracts with different properties derived from the olive industry [triterpenic acid extract (TAE) and a polyphenol extract (PE)] on productive performances in broiler chickens from 0 to 45 d under challenging conditions. In addition, antiparasitic protection of the TAE was evaluated at d 21 and d 28 through intestinal scoring and oocyst counts, as well as the blood antioxidant activity of the PE at d 45. Wood shavings as bedding material came from a commercial farm with a coccidia load sufficient to create a subclinical coccidiosis situation with minor macroscopic lesions, and a nutritional challenge was imposed using poor raw materials to cause intestinal dysbiosis. There were 9 dietary treatments (8 replicates/treatment and 15 broiler chickens/pen), a positive control (PC) supplemented with commercial coccidiostat (Na monensin), 4 increasing concentrations of TAE (30, 60, 90, and 120 ppm), and 4 increasing concentrations of PE (10, 20, 30, and 40 ppm). For the overall experiment the PC had greater average daily gain (ADG) and average daily feed intake (ADFI) (P < 0.001) than the mean of TAE treatments. Besides, the ADG, body weight, and ADFI increased linearly throughout the whole experiment as the TAE level of the feed increased. With respect to the anticoccidial activity, the 120 ppm TAE treatment showed greater concentration of E. acervuline DNA copies at 21 d than the 30 ppm TAE treatment (P < 0.05), the rest of the treatments being intermediate. Concerning the PE treatments, for the overall experiment, ADG was the greatest in the PC treatment (P < 0.001), and the ADFI was similar in the PC treatment to the mean of PE treatments. There was no effect of the PE on antioxidant activity. In conclusion, under the conditions of this study, the inclusion of TAE does not reach the productive performance indicators achieved by a commercial coccidiostat in our intestinal challenge situations. Also, the inclusion of PE has a positive effect on productive performance on the overall period.