Interpretive Summary: Evaluation of essential oils and a prebiotic for newborn dairy calves
By: Dr. Emily Taylor
Pathogenic bacteria pose as one of the leading causes of death in dairy calves due to dehydration from diarrhea. Antibiotics are commonly used to control pathogens, as well as having been a useful aid in improving calf performance. However, concerns about antibiotic resistance have resulted in strict antibiotic use in food animals. Thus, research evaluating alternatives to controlling the pathogenic bacteria are warranted.
An article recently published in Translational Animal Science evaluated feeding a liquid essential oil and prebiotic mixture (EOC) at birth in combination with the EOC in a milk replacer and its effect on growth, health, and the immunity of calves. The three treatments consisted of 1) 24/20% CP milk replacer 2) the milk replacer with the addition of EOC at a rate of 1.25g/d, or 3) treatment 2 with the addition of calves receiving two 10 mL oral doses of EOC at birth and again at 12h.
Treatment 3, calves receiving EOC after birth and 12h later, had greater IgA titers than those receiving EOC only in the milk replacer. These results suggest an improved immune status of the calves to fight off potential diseases and pathogens. Overall calf growth and health status were not impacted by the combination of essential oils in the milk replacer. The targeted rate of EOC was 2.5 g/d; however, a formulation error resulted in the EOC being underfed at 1.25 g/d. Three calves in treatment 2 died due to clostridial infections. The author made the assumption that the deaths were due to insufficient dosages of the essential oils.
This study resulted in a titration experiment, as previous work had been done at 2.5 g/d. The combination of the data with previous data provides useful information regarding the efficacy of an EOC feeding rate in dairy calves.