FieldDxAcute Undifferentiated Diarrhea of Newborn Farm AnimalsClinical signs, differential diagnosis, treatment and prevention in cattle and pigs.
Overview
A general label for neonatal scours before the specific causative agent has been identified. Any of several possible infectious agents (rotavirus, coronavirus, Cryptosporidium, E. coli, Salmonella) -- "undifferentiated" means the specific one has not yet been confirmed in this case.
Clinical signs
- Loose to watery faeces with varying dehydration, dullness and weakness.
- Enterotoxigenic E. coli: sudden profuse liquid faeces, rapid depression and recumbency, with possible death within 12-24 hours.
- Salmonella: high fever, depression, bloody or mucoid faeces, abdominal pain and straining.
- Clostridium perfringens: acute depression, bloody diarrhoea and abdominal pain, often fatal within hours.
- Rotavirus or coronavirus: moderate depression and voluminous soft faeces with mucus, lasting several days.
- Cryptosporidium: persistent diarrhoea that may not respond to treatment, often with emaciation.
Predisposing factors
- Calves that get too few maternal antibodies through colostrum, which the page calls a key predisposing factor.
- Poor housing, weather exposure, or an inadequate or inappropriate diet.
- Contaminated calving and calf-rearing areas, spread by carrier cows and sick calves.
- Milk replacers with poor-quality or soy protein, or indigestible non-milk carbohydrate.
Treatment
- Eliminate the causative agent where identified, and correct and maintain water, acid-base, and electrolyte balance with oral or parenteral fluid therapy.
- Vaccinating the pregnant dam 6 and 2 weeks before parturition raises colostral antibody levels against the common neonatal diarrhea pathogens.
Source
MSD Veterinary Manual — Diarrhea in Neonatal Ruminants (accessed 2026-08-11)
MSD Veterinary Manual — Diarrhea in Neonatal Ruminants (accessed 2026-10-29)
Condensed and attributed, never reproduced whole. Open the full entry in the app.