Effects of beta-mannanase in corn-soybean meal diets on laying hen performance

Recently, a patented enzyme product (beta-Mannanase, Hemicell(R)) has been shown to improve feed conversion in corn-soybean diets fed to broilers and swine. The mechanism of beta-Mannanase is to degrade beta-mannan, which is an antinutritional factor existing in many legumes, including soybean and c anola meals. The objective of this study was to determine whether or not pe rformance can be improved by including beta-Mannanase in diets of commercia l laying hens, 18 through 66 wk of age. A 2 x 2 x 2 factorial arrangement o f treatments was employed. There were two energy sequences of 2,9262,907-2, 885 and 2,827-2,808-2,786 kcal ME/kg, which changed at 33 and 43 wk of age respectively; two dietary enzyme levels (0 and 110 units/g); and two Hy-Lin e strains (W36 and W77). Hen-day production, hen-housed production, BW, fee d intake, mortality, egg weight, and specific gravity data were collected b iweekly. Data were analyzed in four cycles teach with six 2-wk periods) and also for the whole experiment. beta-Mannanase increased egg weight from 51 .4 to 51.7 g/egg (P < 0.05) in the first 12-wk cycle. This effect was consi stent across energy levels. beta-Mannanase significantly improved hen-day a nd hen-housed production after the first cycle. Hen-day production of the,b eta-Mannanase group was 0.70, 1.07, and 1.5% greater than the control for c ycles two, three, and four, respectively (P < 0.01). After 30 wk of age, av erage hen-day production of hens fed the low-energy diets with beta-Mannana se was similar or superior to that of hens fed the high-energy diets withou t the enzyme. The study indicates that beta-Mannanase is capable of increas ing egg weight in commercial layers at early stages of production, and incr easing egg production, particularly delaying the postpeak decline in produc tivity.