Investigating the effect of available phosphorus and calcium level on the potential of a multi-carbohydrase and phytase complex on growth performance, amino acids and phosphorus digestibility in broilers from 1 to 21 days of age

摘要

An experiment was carried out to investigate the influence of dietary available phosphorus (avP) and calcium (Ca) levels on the nutritional potential of a multi-carbohydrase and phytase complex (MCPC) on the apparent ileal digestibility (AID) of amino acids (AA) and phosphorus (P) and performance of broilers fed with corn-soybean meal based-diets from 1 to 21 day of age. A total of 400 one-day-old male Cobb 500 chicks were allocated to 4 treatments in a randomized complete block design with 2 x 2 factorial arrangements of treatments. The two factors were levels of avP and Ca (adequate =4.5 g avP and 9. 0 g Ca per kg or suboptimal =3.5 g av and 7.5 g Ca per kg) and levels of MCPC supplementation (0 or 200 mL per ton feed). Growth performance, feed intake (FI) and feed conversion ratio (FCR) were measured on day 21. Excreta samples were collected on days 19-21 and ileal digesta were collected from all birds on day 21. There was an interaction between avP and Ca levels and MCPC on the final body weight (P < 0.001), body weight gain (BWG, P < 0.001) and FI (P = 0.002) from 1 to 21 days of age. Regardless of the dietary level of avP and Ca, supplementation with MCPC improved (P < 0.001) the BWG and the FCR. An interaction (P < 0.05) was also observed between level of avP and Ca and MCPC on AID of Cys, Gly, His, Lys, Met, Ser, Thr, Tyr, and Val. The addition of MCPC also improved (P < 0.001) apparent ileal digestibility of overall amino acids (AA) by (4.0% and 5.9%) and P (39% and 37%) for adequate and suboptimal levels of avP and Ca, respectively. This study demonstrated that MCPC is an effective solution to improve the availability of AA and P for broilers and consequently the performance. It also highlighted the need to consider interactions with dietary avP and Ca levels to optimize the nutritional benefits of an enzyme solution combining multicarbohydrase and phytase activities in poultry nutrition.