To observe the effects of supplemental dietary d-α-tocopherol in relation to dietary energy on growth and immune status in dairy calves, 32 newborn Holstein bull calves were assigned to 1 of 4 treatments for 5 wk in a 2 × 2 factorial, randomized complete block, split-plot design. Calves received moderate growth (MG) or low growth (LG) all-milk dietary treatments, formulated to support daily gains of 0.5 or 0.25 kg/d, respectively, per the dietary energy recommendation for milk-fed calves according to the National Research Council's Nutrient Requirements of Dairy Cattle. Calves in both groups were either injected i.m. with Vital E-A+D (injectable solution of vitamins E, A, and D) on d 1 and supplemented with Emcelle Tocopherol (micellized vitamin E) via milk daily (MG-S and LG-S), or were not supplemented (MG-C and LG-C) during the study period. Total weight gain of MG calves was greater than that of LG calves and tended to be greater in MG-S calves than in MG-C calves. Calves receiving vitamin supplementation demonstrated greater concentrations of plasma α-tocopherol, retinol, and 25-(OH)-vitamin D than did control calves, whereas MG calves demonstrated a lower concentration of plasma α-tocopherol than did LG calves. The apparent increased utilization of α-tocopherol by MG calves was accompanied by a rise in serum haptoglobin, a positive acute-phase protein and indicator of inflammation, especially in MG-C calves. Serum amyloid A, also a positive acute-phase protein, was not different among groups, but was elevated from baseline in all groups during wk 1 through 3. Plasma IgG1 concentrations were higher in MG-S and LG-S calves than in their nonsupplemented dietary counterparts, whereas plasma IgG2, IgA, and IgM concentrations were not different among groups. In summary, dietary supplementation of d-α-tocopherol improved plasma α-tocopherol status and tended to increase growth in calves fed for 0.5 kg of average daily gain. Vitamin supplementation ameliorated the rise of serum haptoglobin associated with acute inflammation in MG calves, and may have improved passive transfer of maternal antibody. These results indicate a role for α-tocopherol in prevention of proinflammatory state associated with greater dietary energy and onset of infectious disease.

Thirty Holstein calves were obtained from 2 dairy farms in central Iowa at birth and randomly assigned to 1 of 6 treatment groups: (1) colostrum deprived (CD), no vitamins; (2) colostrum replacer (CR), no vitamins; (3) CR, vitamin A; (4) CR, vitamin D3; (5) CR, vitamin E; and (6) CR, vitamins A, D3, E, with 5 calves per treatment in a 14-d study. Calves were fed pasteurized whole milk (CD) or fractionated colostrum replacer (CR) at birth (d 0) and injected with vitamins according to treatment group. From d 1 through d 14 of the study, all calves were fed pasteurized whole milk (PWM) supplemented with vitamins as assigned. All calves were inoculated with Mycobacterium avium ssp. paratuberculosis on d 1 and 3 of age. Calves fed CR acquired IgG1 and haptoglobin in serum within 24 h of birth, whereas CD calves did not. The CR-fed calves were 2.5 times less likely to develop scours, and CR calves supplemented with vitamins D3 and E also demonstrated a decreased incidence of scours. Serum vitamin levels of A, D, and E increased within treatment group by d 7 and 14 of the study. Interestingly, synergistic effects of supplemental vitamins A, D3, and E on serum 25-(OH)-vitamin D were observed at d 7, resulting in higher levels than in calves administered vitamin D only. Further, vitamin D3 deficiency was observed in CD and CR calves fed a basal diet of pasteurized whole milk and no supplemental vitamins. Colonization of tissues with Mycobacterium avium ssp. paratuberculosis was negligible and was not affected by colostrum feeding or vitamin supplementation. Results demonstrated passive transfer of haptoglobin to neonatal calves, and potential health benefits of supplemental vitamins D3 and E to calves fed pasteurized whole milk.

Avi-Lution® is a defined, patented, synbiotic product containing Saccharomyces cerevisiae, Enterococcus faecium, and Bacillus spp. Broiler chickens (n = 1,250) were experimentally treated as uninoculated controls (uCon), inoculated controls (iCon) with Clostridium perfringens, or inoculated and treated with bacitracin methylene disalicylate (BMD) at 55 mg/kg as an infected/treated control or Avi-Lution® at 1.0 (AvL1) or 2.0 (AvL2) g/kg in feed for 42 d. Each treatment was applied to 10 replicate pens of 25 straight-run, newly hatched chicks. Pens treated with AvL1, AvL2, or BMD showed improved growth, feed efficiency, or mortality from necrotic enteritis compared with iCon pens at d 14, 28, and 42. No differences in these measurements, however, were observed between pens treated with AvL1 and AvL2, which suggests that Avi-Lution® was effective at 1.0 g/kg in feed. Despite improved performance, BMD, AvL1, and AvL2 treatments did not decrease the severity of intestinal lesion scores through 42 d of age compared with the infected control. These results demonstrate that Avi-Lution® improved growth performance and feed conversion rates in broilers challenged with Clostridium perfringens despite no difference in severity of intestinal lesion scores.