Granulometria e forma física da ração para frangos de corte

Abstract

Two experimental phases were conducted to evaluate the effects of corn particle size and diet physical form on the performance and production cost in broilers (Phase I) and the relative weight of organs (Phase II). A number of 936 male chickens and 1008 females were used in the first experimental phase and 312 male chickens and 312 female chickens in phase II. The broilers used was Cobb® from 1 to 45 days old (I) and from 1 to 35 days old (II). Treatments consisted of two mash and two pelleted diets (ground corn through sieve 3.8 mm and 7.0 mm). Similar treatments were used for both experimental phases. The experimental design was completely randomized in a 2 x 2 factorial design (two particle sizes x two physical forms), with six replicates of 39 birds each for males and six replicates of 42 birds each per treatment for females for phase I, and six replicates for II. In experimental phase I, PDI from pelleted physical form that was produced with 3,8mm grinding showed better results (p 0.05) than other treatments just for the males from 1 to 45 days of age. Birds fed by pelleted diets had greater feed intake, weight gain and better feed conversion than those fed mash diet for all females stages of raising and for males, just on phase from 1 to 23 and 1 to 41 days (p 0.05). No significant difference (p> 0.05) was observed between the type of processing and the grinding for males feed intake from 1 to 45 days stage. There was no influence of the physical form and particle size on the feasibility of birds in any phase (p> 0.05). For the second experimental phase birds fed by pelleted diets had higher abdominal fat than birds fed by mash, therefore they presented lower gizzard relative weight (p 0.05).