Colostrum

Colostrum is an important substance for young mammals, including puppies and kittens, and is responsible for a large percentage of passive transfer of immunity from the mother to the offspring. In animals that do not receive maternal placental transfer of immunity (e.g. ruminants), colostrum is almost necessary for life. In other species, colostrum is an important substance early in life, though not completely required for immune system development. In addition to antibodies, colostrum also contains important growth factors and bioactive compounds that are important for infant growth. During the first ~24 hours after birth, the newborn’s gut has increased permeability to more effectively absorb the bioactive compounds present in colostrum.

Given the important functions colostrum plays on the growth and immune system of newborns, bovine colostrum (BC) has been investigated in adult humans to establish whether a benefit in overall immune health or gut health can be detected when given to adults. Systematic reviews in human medicine have shown interesting effects in preventing upper respiratory illness in athletes and reducing intestinal permeability in both healthy and sick subjects, though conflicting results persist in pediatric and geriatric populations(Guberti et al., 2021).

In veterinary medicine, specifically regarding adult dogs, research suggests that bovine colostrum may indeed influence systemic and local immune responses. Dogs fed BC-supplemented diets have demonstrated significantly higher vaccine-specific plasma IgG levels and increased fecal IgA levels, suggesting a positive impact on gut-associated lymphoid tissue(Satyaraj et al., 2013). Furthermore, supplementation has been linked to increased diversity and stability within the gut microbiota.

Thus, while the profound effects of colostrum in newborns are unique due to neonatal gut permeability, data suggests that oral administration in adults may still provide measurable immunomodulatory benefits. There is increasing research being conducted in young puppies and kittens evaluating the use of bovine colostrum in this growing pediatric population. However, that assessment is beyond the scope of this review.

Lastly, the harvesting of bovine colostrum deserves consideration. Since bovine colostrum is crucial for the health of the newborn calf, ethically sourced colostrum should be collected when there is a “surplus” of colostrum, and not at the expense of denying the newborn calf. Establishing this data in commercially available products appears worthwhile.