Background: Although adequate colostrum intake and properly used antibiotics can provide much protection for the bovine neonate, increased antibiotic scrutiny and consumer demand for organic products have prompted investigations of natural immunomodulators for enhancing calf health. One plant-based immunomodulator, Morinda citrifolia (noni) fruit, is a wellrecognized natural product that has a broad range of immunomodulatory effects.Hypothesis: Neonatal calves fed noni puree would demonstrate whole blood phagocytic capacity in Gram-negative and Gram-positive in vitro assays.Animals: Blood samples from 18 neonatal Holstein bull calves. Methods: Calves were divided into 2 groups: Group 1 comprised control calves, whereas Group 2 received 30 mL of noni puree twice a day in milk replacer. Day 0 blood samples were obtained between 36 and 48 hours of age before the first feeding of puree. Ethylenediaminetetraacetic acid anticoagulated blood was collected from each calf on days 0, 3, 7, and 14. Bactericidal assays were performed to estimate the percentage killing of Escherichia coli and Staphylococcus epidermidis.Results: Blood samples from noni puree-fed calves displayed significantly more E. coli bacterial killing than did controls on day 14, and although differences were not significant on days 0, 3, and 7, bacterial killing progressively increased over time. There was no significant difference between the groups for S. epidermidis killing.Conclusions and Clinical Importance: The immunomodulatory effect of noni puree may prove valuable in the future as production animal antibiotic use becomes more restricted. Additional clinical trials are warranted to investigate the clinical application of noni puree in promoting calf health.

Developmental immaturity of the immune system renders neonatal calves vulnerable to infectious causes of morbidity and mortality. Juice made from the Morinda citrifolia fruit (noni) reportedly has immune enhancing, antibacterial, and antiinflammatory effects. The objective of this study was to evaluate the potential immune-modulating effects of feeding noni puree to neonatal calves on T-cell activation on CD4 + , CD8 + , and γδ T cells. Sixteen newborn Holstein bull calves were acquired in pairs from local dairies and confirmed to have adequate passive transfer at 24 h of age. The calves were divided into 2 groups: group 1 (n = 8) was composed of control calves, and group 2 (n = 8) received 30 mL of noni puree twice daily in milk replacer. Blood samples were collected from each calf on d 0, 3, 7, and 14. Mitogeninduced activation of CD4 + , CD8 + , and γδ T-cell receptor-positive T cells was evaluated by measurement of the upregulation of the interleukin 2 receptor, CD25, using 2-color flow cytometry. Concanavalin A and phytohemagglutinin were used as global mitogens. Noni puree-fed calves had an increase in CD25 expression on concanavalin A-stimulated CD4 + (P = 0.03 for parametric and nonparametric analysis) and CD8 + T cells (P = 0.04 for parametric analysis) on d 3 of the study, or approximately 4 to 5 d postpartum. There was also an effect over time for CD8 + T cells (P = 0.03 for nonparametric analysis). Further studies are warranted to determine the cellular mechanisms responsible for these findings and whether noni supplementation in dairy calves translates to improved health and well-being.

We have previously reported that Morinda citrifolia (noni) puree modulates neonatal calves developmental maturation of the innate and adaptive immune system. In this study, the effect of noni puree on respiratory and gastrointestinal (GI), health in preweaned dairy calves on a farm with endemic salmonellosis was examined. Two clinical trials were conducted whereby each trial evaluated one processing technique of noni puree. Trials 1 and 2 tested noni versions A and B, respectively. Puree analysis and trial methods were identical to each other, with the calf as the experimental unit. Calves were designated to 1 of 3 treatment groups in each trial and received either: 0, 15 or 30 mL every 12 hr of noni supplement for the first 3 weeks of life. Health scores, weaning age, weight gain from admission to weaning, and weaned by 6 weeks, were used as clinical endpoints for statistical analysis. In trial 1, calves supplemented with 15 mL noni puree of version A every 12 hr had a higher probability of being weaned by 6 weeks of age than control calves (P = 0.04). In trial 2, calves receiving 30 mL of version B every 12 hr had a 54.5% reduction in total medical treatments by 42 days of age when compared to controls (P = 0.02). There was a trend in reduced respiratory (61%), and GI (52%) medical treatments per calf when compared to controls (P = 0.06 and 0.08, respectively). There were no differences in weight gain or mortality for any treatment group in either trial.