The effect of drying method temperature, collection method, and marker type on apparent ileal amino acid digestibility in 21-day-old broilers fed corn-soybean meal-barley based diet

Abstract

For accurate estimation of nutrient digestibility, an ideal drying and sampling method is required to preserve the quality of the digesta. A standard corn-soybean meal (corn-SBM) broiler starter diet was fed from d 0 to 10 before birds were placed on the experimental diets until d 21. One hundred and sixty-eight male Cobb 500 broiler chicks were used to evaluate the effect of two drying methods (freeze-dryer vs. forced air-oven) and two drying temperatures (40 vs. 55°C) (Exp 1), while ninety-six chicks were used to evaluate the effect of flushing and squeezing as well as marker types (titanium vs. chromium) on apparent ileal DM, N, Ca, P, and AA digestibility (Exp 2). There were seven (Exp 1) or eight (Exp 2) replicate cages per treatment with 6 birds/cage. Digesta from the distal two thirds of the ileum was obtained from birds following euthanasia on d 21 by squeezing (Exp 1) and squeezing or flushing (Exp 2). Samples collected were stored in the freezer at -20°C until they were either freeze-dried (FD) or oven-dried (OD) at 40 or 55°C. There were no interactions between the drying methods and drying temperatures (Exp 1) on apparent ileal DM, N, and AA digestibility. Met had the highest (92.3%) while Cys had the lowest (73.8%) digestibility value. In Exp 2, no interaction between sampling methods and marker types was observed. The effect of sampling methods was not significant except for Arg and Met where squeezing resulted in higher (P < 0.05) digestibility values. Furthermore, apparent ileal His, Ile, Cys, Ser, and Tyr digestibility tended to be higher (P < 0.1) in squeezed digesta compared to the flushed digesta. Results from these studies showed that OD ileal digesta at 40 or 55°C had no negative effect on apparent ileal AA digestibility. Likewise, marker type did not influence apparent ileal AA digestibility values.

High doses of phytase on growth performance and apparent ileal amino acid digestibility of broilers fed diets with graded concentrations of digestible lysine

“…Therefore, the effect of treatment on the AID of amino acids can still be described as reported because the magnitude of the response to phytase would be the same, regardless of the drying conditions. In addition, the AID coefficients for amino acids in the current trial are similar to the AID of amino acids reported by Cowieson et al (2006) and Olojede et al (2018) using similar drying conditions or greater than those reported by Ravindran et al (2001), also using digesta samples dried at 80 °C. The absolute amino acid digestibility coefficients obtained from any experiment are an estimate of the average amino acid digestibility over the duration of the trial and reported as a point in time measurement.…”

Effect of low‐temperature drying on the nitrogenous compounds and inositol phosphates in broiler chickens and cecectomized laying hen excreta

“…The drying methods did not consistently affect the amino acids, but the highest concentrations were observed when the samples were dried at 60°C for most amino acids. In another study, prececal amino acid digestibility did not differ when the digesta samples were freeze‐dried or dried in a forced‐air drying chamber at 40 and 55°C (Olojede et al 2018). We are not aware of any published study describing the effects of drying on the inositol phosphate concentrations in excreta.…”