Inclusão de lisolecitina ou β-glucanas na dieta líquida de bezerros leiteiros: efeitos no desempenho, saúde e metabolismo

Abstract

Inclusion of lysolecithin or ß-glucans in the milk replacer for Holstein dairy calves:effects on performance, health and metabolism The study aimed to investigate how addition of β-glucans can affect calf's growth performance, health, and blood metabolites. Two experiments were conducted with thirty-two Holstein dairy calves each (16 calves per treatment/ experiment). Calves were individually housed in tropical shelters and blocked according to sex, date and weight at birth and randomly assigned to 1 of the treatments of Experiment 1: 1) Control; 2) Milk replacer supplemented with lysolecithin (4 g / day); and Experiment 2: 1) Control; 2) Milk replacer supplemented with ß-glucans (2g / day). Feed intake, and health score and fecal score were recorded daily during 56-d study in both experiments. Body weight were measured weekly and body measures biweekly in both experiments. Blood samples were collected weekly to determine metabolic indicators. Lysolecithin had no effect on dry matter intake (P >0.05). However, the lysolecithin improved average daily gain (P <0.04), final body weight (P <0.05), feed efficiency (P <0.02), and fecal score (P =0.04). Blood parameters were also not affected, except for total protein concentrations (P <0.01), which were lower in supplemented calves. In the experiment 2 the main effect of providing betaglucans to Holstein dairy calves during preweaning period is the improvement in feed efficiency (P =0.04), final body weight (P =0.05). Moreover, control calves were more likely to have a diarrhea bout than β-glucans calves OR 22.46 (95% CI: 15.14-33.32; P <0.0001). Overall, lysolecithin and β-glucans supplementation may improve feed efficiency, final body weight and fecal score during the preweaning phase.