Feeding colostrum and transition milk facilitates digestive tract functionality recovery from feed restriction and fasting of dairy calves

The objective of this study was to evaluate the digestive tract recovery and metabolism feeding either bovine colostrum (BC), transition milk (TM), or replacer (MR) after an episode feed restriction fasting (FRF) in dairy calves. Thirty-five Holstein male calves (22 ± 4.8 d old) were involved a 50-d study. After 3 2 L rehydration solution twice daily 19 h (d 1 study), randomly assigned one 5 treatments (n = 7): offered pooled BC during 4 (C4) 10 (C10) days, TM (TM4) (TM10) MR for (CTRL) at rate 720 g/d DM content. Then, all fed same program, gradually decreasing from 3L once 12.5% until weaning 42), concentrate feed, water, straw ad libitum 50. Citrulline, Cr-EDTA, β-Hydroxybutyrate (BHB), nonesterified fatty acids (NEFA) serum complete blood count (CBC) determined on −3, 1, 2, 11 relative FRF, except BHB NEFA −3. Volatile (VFA), lactoferrin (LTF), IgA microbiota (Firmicutes Bacteroidetes ratio Fecalis prausnitzii) analyzed feces before morning feeding. Health scores recorded −3 14 as well 23 30. Feed concentrate, MR, intake daily, body weight weekly afterward. Calf performance, intake, CBC, fecal LTF concentrations parameters similar among throughout Serum greater TM4, TM10 C10 compared with CTRL ones 11, lower than other treatments, long (C10 TM10) remained those shorter (C4 TM4) CTRL. citrulline but they C4, C10, 5, only Fecal tended be CTRL, calves, C4 animals. propionate proportion lesser TM4 while butyrate non-normal Results showed that may help recover intestinal functionality, provide gut immune protection, increase liver acid oxidation FRF episode.