ImmuCell is a small animal health company focused on preventing scours (diarrhea) in newborn calves. Scours is the leading cause of death in pre-weaned calves, and ImmuCell's core product, First Defense, addresses this by delivering pre-formed, pathogen-specific antibodies directly to newborn calves at birth. Unlike vaccines, which require an active immune response, First Defense provides passive, immediate immunity — a key differentiator that ImmuCell argues results in significantly higher neutralizing antibody levels than competing vaccine-based products. First Defense covers the three primary causes of neonatal calf scours: E. coli, bovine coronavirus, and bovine rotavirus, and is sold in several formats including bolus, gel tube, and a bulk powder for large calf-rearing operations. The higher-tier Tri-Shield format, covering all three pathogens, accounts for roughly two-thirds of product sales. ImmuCell sells through national and regional animal health distributors to dairy operations, calf ranches, and beef producers. Revenue is driven by dose volume, price — First Defense carries roughly a 2.5x premium to competing vaccines — and mix shift toward higher-priced formats. Manufacturing costs are largely fixed, so gross margins are sensitive to production volumes. ImmuCell previously pursued Re-Tain, a mastitis treatment, as a second product line, but halted that effort after repeated FDA approval delays and is now redeploying those manufacturing assets to expand First Defense capacity. Growth priorities include domestic sales force expansion, international markets, and yield improvements to grow production capacity.