A Narrative Review on the Unexplored Potential of Colostrum as a Preventative Treatment and Therapy for Diarrhea in Neonatal Dairy Calves

SIMPLE SUMMARY: The rate of death and disease in young dairy calves is alarmingly high, with diarrhea accounting for over half of all disease incidence. The majority of diarrhea cases are treated with antimicrobials, which may not be warranted. There is increasing concern related to the use of antimicrobials in food animals due to the emanant development of antimicrobial resistance. Bovine colostrum is densely packed with hundreds of nutrients and bioactives specifically tailored to improve calf health and development. As such, colostrum may have potential to be used an alternative to antimicrobials for the treatment of diarrhea. The objective of this review is to outline the causation and implication of diarrhea in young dairy calves and to explore the benefits of colostrum and its potential use as a therapy and preventative for diarrhea in pre-weaned calves. ABSTRACT: Diarrhea is the leading cause of morbidity and mortality in pre-weaned dairy calves and, as such, represents a significant animal health and welfare concern. Furthermore, digestive disease early in life is associated with several long-term consequences such as reduced growth rate and decreased milk yield during the first lactation, thus generating severe economic losses. The majority of diarrheic cases in young calves are treated with antimicrobials; however, it is necessary to develop alternative treatments, as excessive antimicrobial usage can lead to antimicrobial resistance and can negatively impact the gut microflora of a calf. Bovine colostrum is abundant in immune and bioactive factors that improve immune function and development. This rich and natural combination of immunoglobulins, natural antimicrobial factors, growth factors, anti-inflammatories and nutrients may be an attractive alternative to antimicrobials in the treatment of diarrhea in young dairy calves. There is evidence that supports the use of colostrum as an early treatment for diarrhea in young calves. Future research should investigate its therapeutic and economic effectiveness.