Performance, sanity and blood parameters in dairy calves supplemented with mannan oligosaccharides and mannan-rich fraction

This study aimed to evaluate the potential of mannanoligosaccharides (MOS) and the mannan-rich fraction (MRF) to improved performance in suckling calves. Forty-eight calves were used, 20 males and 28 females. The calves were allocated to four experimental groups: control group (basal diet: concentrate and whole milk); MRF: basal diet + 3g/animal/day of MRF (Actigen™); MOS: basal diet + 2g/animal/day of MOS (Viligen™); MRF+MOS: basal diet + 3g/animal/day MRF + 2g/animal/day MOS. Calves were monitored from birth to 60 days of age for rectal temperature, fecal score, concentrate intake, performance, and blood parameters. The data were analyzed as a randomized block design, adjusting the calf's birth weight as a covariate. The data were subjected to analysis of variance, and when significant, the Tukey's test was applied, with significance considered at P < 0.05. To evaluate the change in fecal score, fever occurrence and blood parameters throughout the age, we assessed five distinct variance-covariance matrix structure with significance considered at P < 0.05. Performance and health were not affected by supplementation (P>0.05), therefore, calves exhibited higher fecal scores, greater number of days with diarrhea and higher rectal temperatures, during second and third weeks of age (P<0.0001). It was observed that the blood parameters variables were similar between the treatments (P>0.05), however, we observed that all blood parameters change according to the age (P<0.0001). Prebiotic supplementation did not influence health, performance or blood parameters in milk-fed calves, however, significant age-related changes in fecal scores, rectal temperature, and blood metabolites were observed over age.