Double-buffered sodium butyrate addition improved egg mass and feed efficiency of layers fed low energy-protein diet

     

In a context of rising prices of feed ingredients, the improvement of the overall feed digestibility and maximum utilization of nutrients in the feedstuffs should be a priority. Previous studies have shown the benefit of a double-buffered sodium butyrate (DBSB) on the performance and intestinal health of broilers fed low energy and protein diets (LEP). The aim of the study was to evaluate the effect of this uncoated form of sodium butyrate (DBSB) on the performance and feed efficiency of layers. A total of 384 Hy-line W-80 layers were allocated in individual cages in a completely randomized design. For each treatment there were 8 repetitions, being each line of 24 individual cages an experimental unit. The layers were weighted at the beginning and at the end of the trial. From week 56 to 59 of age two diets were used for dietary treatments. LEP diet was formulated to obtain a reduction in energy and protein considering the standard recommendations (Hy-line, 2019): -3% of AME, -2,5% of Crude Protein and the same amount reduction for digestible lysine, threonine, and sulfur amino acids (M+C). LEP+DBSB group was fed with the LEP diet supplemented with 600ppm of DBSB (Butylin 54, Dietaxion SAS). The measured parameters were feed intake (FI), number of collected eggs (EggN) and their weight (EggW), enabling to calculate the mass of eggs produced (EggM) and the feed conversion ratio (FCR). Mortality was used to correct the feed intake. Data were statistically analysed using ANOVA, followed by a Duncan test for comparisons of means. No difference in FI, EggN and EggW was observed between treatments (P> 0.05). However, hens in LEP group laid significantly (P< 0.05) less EggM (3,1%). Regarding the FCR, significant differences were obtained between the groups (P< 0.05) for feed efficiency per kg of egg mass, with the LEP diet presenting the worst performance (3,7%). There was no significant difference in FCR per dozens of eggs (P> 0.05) but tended to be improved with DBSB (2,8%). The use of DBSB in layers fed LEP diets improved egg mass and feed efficiency per kg egg mass, so could be considered an important strategy to feed cost savings and excretion reduction.

Key Words: layers, sodium butyrate, egg mass, feed efficiency.