Influence of initial body weight, beak trimming, and inclusion of Na-butyrate in the diet on growth performance, body weight uniformity, and digestive tract traits of brown pullets from hatching to 16 wk of age

Abstract

The influence of initial BW and beak trimming on growth performance, BW uniformity, and gastrointestinal tract (GIT) traits was studied in brown pullets fed diets supplemented or not with 0.3% Na-butyrate (Butirex C4; Novation 2002 S. L.) from hatching to 16 wk of age. The GIT traits studied were the pH, relative weight (RW, g/kg BW), and fresh contents of the GIT organs and the relative length (cm/kg BW) of the small intestine and cecum, at 5, 10, and 16 wk of age. There were 12 treatments organized as a 2 × 2 × 3 factorial, with the initial BW of the pullets at hatching (34.2 vs. 37.9 g), beak trimming procedure [low (L-0) or high (H-0) intensity of infrared treatment applied at the hatchery, and traditional beak trimming at 8 d of age (F-8)], and inclusion of Na-butyrate in the diet (0 vs. 0.3%) as main effects. No interactions among main effects were detected for any of the variables studied and therefore, only main effects are presented