Determining the average particle size consumed (APSC) between two genetic strains (GS) receiving starter diets varying in feed form (FF) and feed quality (FQ)

A previous companion study utilized a 2 GS (Fast Growing (FG) or High Yielding (HY)) x 2 FF (Crumbles (C) or Intact Pellets (IP)) x 3 FQ (Low, Medium, or High) factorial arrangement to determine their impact on broiler performance. The two FF, C or P, were fed in the starter diet (d 0-18) as one of three FQ: low-2210 µm (C) or 40% intact pellets (IP), medium-3010 µm (C) or 60% IP, and high-3388 µm (C) or 80% IP. From 0-18 d, feeding increased FQ improved overall BW and BWG. The current study determined the APSC from d 0-6 and d 0-18 among these GS, FF, and FQ. This study utilized a sub-sample of pens from the companion study. From d 0-6 and 0-18, HY GS had a higher APSC. At d 0-18, GS x FF interacted, demonstrating that APSC only differed between GS when pellets were fed, with HY consuming a larger size. A FF x FQ interaction on 0-6 and 0-18 d demonstrated that, regardless of FF broilers fed high FQ, had larger APSC. For birds fed low and medium FQ as a C, APSC was larger, but smaller when fed as IP. Correlations were found showing that as APSC increased, d 0-6 BW, BW gain, and FCR improved; this also occured for d 0-18 FCR. Data suggest that APSC is dependent upon GS and FF presented; further research is needed to verify APS preference when provided ad libitum amounts of each particle size.