Enrichment of medium-quality colostrum by adding colostrum replacer, combined or not with transition milk in the feeding of dairy calves.

Fifty Holstein calves were allocated in randomized blocks and distributed in a 2 × 2 factorial arrangement; (A) two sources of Ig: (1) Control: bovine colostrum (25% Brix); (2) Enriched colostrum: mid-quality bovine colostrum (20% Brix) enriched with colostrum replacer to 25% Brix; and (B) two transition feeding diets: (1) Whole milk (WM): supply of 4 L/day of whole milk for 3 days after the colostrum feeding; and (2) Formulated transition milk (FTM): supply 4 L/day of whole milk enriched with 70 g/L of colostrum replacer for 3 days after the colostrum feeding. Blood samples were collected at 0, 24, 48, and 72 h of age to determine total serum protein (TSP), glucose, non-esterified fatty acids (NEFA), erythrocyte and leukocyte concentrations. IgG was measured at 48 h. During the preweaning period, calves received 6 L/day of whole milk. Blood samples were collected weekly to determine TSP, glucose, and lactate. The colostrum protocols were equally efficient for transfer of passive immunity with IgG concentration at 48 h ≥ 49.6 g/L. Colostrum or transition feeding program did not influence the erythrocyte and leukocyte concentrations. The TSP concentration measured until 72 h was higher for calves fed maternal colostrum. Calves fed milk in the transition period had higher glucose concentrations. Calves receiving bovine colostrum and FTM had higher glucose concentrations in the preweaning period, while the enriched colostrum decreased plasma lactate concentrations. In summary, enrichment of mid-quality colostrum is an alternative in situations of a shortage of high-quality colostrum; however, feeding 4 L/day of FTM only for 3 days after colostrum feeding does not show additional benefits.

Essential oil blend supplementation in the milk replacer of dairy calves: Performance and health.

Supplementation of dairy calves with essential oils in the liquid diet can reduce the incidence and severity of infectious diseases and promote better performance. Our objective was to evaluate an essential oil blend containing peppermint, eucalyptus, and menthol crystals and its effect on performance and health during the pre and postweaning period of dairy calves. At birth, 40 dairy calves (34 males and 6 females) were blocked according to sex and birth weight, randomly assigned to one of two treatments-commercial milk replacer diluted at 14% (MR) and the same liquid diet plus essential oil blend (MREO) at a dose of 4 mL per calf per day, divided into two meals during the first 28 days of life. Calves were individually housed and fed 6 L/d of the liquid diet, divided into two meals, and received starter concentrate and water ad libitum. Weaning was gradually reduced by 1L per day at d 51 until complete weaning at 56 days. After weaning, calves were evaluated until 70 days of age, when the experimental period ended. Intake, fecal, and health scores were evaluated daily, weight and body measures were recorded weekly, and blood parameters were evaluated at weeks 1, 2, 3, 4, and 8. Calves fed MREO tended to have higher total dry matter intake during the preweaning period. Furthermore, MREO calves had lower health scores and fewer days with a health score ≥ 4 (suggestive of bronchopneumonia), tended to lower coughing days and fewer veterinary interventions preweaning, and tended to lower health scores postweaning. The supplementation with a blend of essential oils containing peppermint, eucalyptus, and menthol crystals can reduce respiratory problems. Further studies are needed to investigate the dose and the supplementation period.

Effect of Maternal or Formulated Transition Milk on the Health and Performance of Dairy Calves.

The study aimed to evaluate the effect of maternal or formulated transition milk with colostrum powder on the performance and health of dairy calves. After receiving 12% of their birth weight in high-quality colostrum, 36 Holstein calves (17 males and 19 females) were blocked according to sex, birth date and birth weight (29.16 kg ± 1.34) and randomly distributed into three treatments: (1) Milk: supplying 4 L/d of whole milk (WM) for three days (n = 12); (2) Transition milk (TM): supplying 4 L/d of maternal transition milk for three days (n = 12); (3) Formulated transition milk (FTM): supplying 4 L/d of whole milk enriched with 280 g/d of colostrum powder, for three days (n = 12). Daily feeding was split into two feedings, and after the sixth feeding of the transition diet calves were fed 6 L/d of whole milk and had ad libitum access to water and calf starter until 56 d, when the study ended. Calves fed TM or FTM presented a higher total solids intake (p < 0.05). Concentrations of glucose (p = 0.096) and lactate (p = 0.063), evaluated from 0 h to 72 h, tended to be higher in WM-fed calves compared to TM. There were no effects on calf's health or performance and weight; at the week 8 averaged 65.06 kg ± 1.85. All treatments resulted in adequate performance and good health, however, the potential benefits of providing TM or FTM were not seen in this study. The transition milk composition and the number of meals after colostrum feeding need more investigation.