DIGESTIVE ALLOMETRY IN BROILERS SUPPLEMENTED WITH OREGANO FLOUR AS A GROWTH PROMOTER

Abstract

The objective of the trial was to evaluate the relative weight of different organs and allometric changes of the gastrointestinal tract of broilers, supplemented with oregano leaf meal (HO) as a growth promoter, in mixing proportions with the balanced feed (AB). At 21 days of the starter phase and 42 days of fattening, the weight of the proventriculus, gizzard, duodenum, jejunum and ileum was quantified; as well as, their respective allometric coefficients were determined; in addition, the entire small intestine. A completely randomized experimental design was used, with a total of 208 Ross line chicks distributed in four treatments: T1= 100% balanced feed (AB100%); T2= Balanced feed+0.25% oregano flour (AB+0.25%HO); T3= Balanced feed+0.50% oregano flour (AB+0.50%HO) and T4= Balanced feed+0.75% oregano flour (AB+0.75%HO), with four repetitions, each experimental unit constituted by 13 birds. An analysis of variance was performed on the quantified variables and the average values were compared by Tukey at 5% probability. The concentration of 0.25% HO in combination with BA favored the values obtained for the relative weights at 21 and 42 days of the duodenum, jejunum, ileum, as well as for the entire small intestine. All organs showed slow allometric growth (CA<1) in relation to body weight in the initial and fattening phase, except for the proventriculus, which showed greater growth (CA>1).