Abstract

CORTES CUEVAS, Arturo et al. Lysine bioavailability in two soybean meals with different level of urease activity in broiler chicks. Rev. mex. de cienc. pecuarias [online]. 2014, vol.5, n.1, pp.17-24. ISSN 2448-6698.

In order to study bioavailability of lysine of two soybeans meals (PSA and PSB) for broilers with different urease activity (UA of 0.11 and 0.17 units of pH change), an experiment was performed. Two hundred and ten (210) chicks Ross were used from 1 to 21 d of age, in a completely randomized design with 7 treatments with three replicates each one. Treatments were: 1) Basal diet sorghum-soybean meal (deficient in lysine), 2) Basal diet+0.05% L-lysine, 3) Basal diet+0.10% L-lysine, 4) Basal diet+0.05% lysine from PSA, 5) Basal diet+0.10% lysine from PSA, 6) Basal diet+0.05% lysine from PSB and 7) Basal diet+0.10% lysine from PSB. The growth results obtained were explained by multiple linear regression equation, based on the data of weight gain, consumption of synthetic lysine and intakes of lysine from soybean meals: Y=X1+ Y= 375.419 + 0.0378 X1 + 0.0366 X2 + 0.0376 X3; where X1 accounted supplementation with L-lysine, X2 with PSA (with addition of raw hull) and X3 with PSB (with addition of cocked hull). Comparison of the PSA or PSB slopes with the L-lysine slope (i.e. 100 % bioavailability) showed them all to have >95 % lysine availability: PS A= 97 %, PSB= 99 %. These results indicate that UA of soybean meal affected the bioavailability of lysine; therefore more than 0.12 urcase activity units of pH change, lower is the availability.

Keywords : Soybean meal; Urease activity; Broilers; Lysine bioavailability; Performance.