Inclusion of Secale cereale and Pentosanases in the Ration of Laying Hens: Exploring its Effect on Egg Production and Concentrate Intake and Searching the Optimal Combination in a Diet

Background and Objective: Antinutritional factors are usually found in cereals, these correspond to molecular complexes structured by carbohydrates present in the grains, which increase the viscosity of the food bolus, resulting in diminished organic matter digestibility, food intake and egg production. These polymers are known as soluble non-starch polysaccharides (NSPs). The objective of this experiment was to assess the effect of incorporating Secale cereale (SEc) and pentosanases (EEp) in the diets of laying hens (Lohmann LSL hybrid) on their egg production (EP) and concentrate consumption (CC), optimal combination between the main factors was estimated for EP and CC. Materials and Methods: The trial was carried out on a commercial egg-producing poultry farm (Valparaíso Region, Chile). A completely randomized experimental design was used, with a 4×5 factorial arrangement of two factors (four levels for SEc and five levels for EEp). Ten repetitions were used per treatment, where each experimental unit corresponded to one cage with five hens. A contour curvature analysis was carried out to determine the optimal level of inclusion of SEc with EEp. The experimental period lasted 84 days. Results: There was an interaction effect of SEc and EEp on EP and CC. The optimum level of inclusion for EP was 200 g kg–1 SEc and 1 g kg–1 EEp, with average production of 396 units, for CC, the optimum value observed corresponded to 200 g kg–1 SEc with 0.5 g kg–1 EEp (47.56 kg). The lowest EP and CC responses, regardless of the EEp level in the diet, was observed with the inclusion of 600 g kg–1 SEc. The contour area curvature analysis for EP gave a high response curve zone between 130-390 g kg–1 SEc and 0.38-1.57 g kg–1 EEp, the highest response levels for CC were 120-350 g kg–1 SEc and 0.43-1.75 g kg–1 EEp. Conclusion: In this research it was possible to establish that high level of SEc inclusion in the diet affects negatively eggs production and concentrate intake. However, when pentosanases are included in the diet improve these variables. These results suggest possible antinutritional factors of SEc that could have caused negative effects on the hens' physiological response.