Pica is a compulsive craving to ingest substances that are not normal feed items, such as soil, sand, wood, feces, or other non-nutritive materials. In horses, pica can reflect nutritional deficiencies (particularly of sodium, phosphorus, or trace minerals), gastrointestinal parasitism, boredom, or underlying systemic disease. Coprophagy (eating feces) is normal in foals during the first few weeks of life as a mechanism to inoculate the hindgut with beneficial microflora, and should not be confused with pathological pica. Wood chewing in mature horses, while sometimes classified under pica, more often reflects inadequate forage intake or stereotypic behavior rather than a mineral hunger. Dirt and sand ingestion can lead to sand accumulation in the large colon, contributing to sand colic, a form of gastrointestinal obstruction; this risk is heightened in horses kept on sandy substrates without adequate forage. Diagnosis involves dietary history, serum biochemistry and mineral analysis, and fecal egg counts to rule out gastrointestinal parasite burden. Management addresses the underlying cause: correcting mineral imbalances through dietary supplementation, increasing forage availability, and enriching the horse’s environment to reduce boredom. Rubber stall mats and raised feeders reduce incidental soil ingestion. For context on correcting mineral gaps through ration balance that minimize nutritional gaps and on sand colic from accumulated ingested soil related to sand accumulation.
Further Reading
- pica (Wikipedia)
- For behavioral context and management of pica and related stereotypies: behavior problems in horses including pica — Merck Veterinary Manual