EFEITO DA UTILIZAÇÃO DE MANANOLIGOSSACARÍDEOS (MOS) E DE ÁCIDOS ORGÂNICOS ASSOCIADOS À MOS, COM E SEM ANTIBIÓTICOS, NA DIETA DE POEDEIRAS PRODUTORAS DE OVOS AVERMELHADOS

The present study aimed to compare the productive performance of Isa Brown -egg laying hens (32 to 52 weeks of age) fed a corn-soybean meal diet. The birds were randomly allocated into individual cages (40 cages/treatment) in a total of 240 animals. Feed and water were provided ad libitum. Treatments consisted of: T1- control (basal diet=BD); T2- D + antibiotic; T3- BD + mannanoligosaccharide (MOS) (0.05%); T4- BD + antibiotic + MOS; T5- BD + organic acid/MOS (OAM) (0.1%) and T6- BD + antibiotic + OAM. Body weight, egg production, egg weight, egg mass, feed conversion/dozen eggs and per egg mass, internal quality of eggs (egg yolk color, albumen height, Haugh units), eggs external quality (specific gravity, egg shell percentage) and time of storage were not affected by dietary treatments. The data were subjected to ANOVA and the means were compared by Tukey test. Results indicated that birds fed OAM and MOS without antibiotic had lowest feed consumption, without altering laying performance. KEYWORDS: Antibiotic, growth promoters, laying hens, mannanoligosaccharide, organic acids.