Fluid therapy for calf scours is stratified by dehydration severity, with oral electrolyte solution (OES) for mild-to-moderate cases and intravenous (IV) fluids reserved for severe dehydration.
Mild-to-moderate dehydration is managed with OES. Oral rehydration is of particular value because it permits treatment at the initial signs of scours, which reduces the severity of the condition in many cases.FDA DailyMed An… Re-Sorb (glucose, glycine, and electrolytes for oral solution) is one commercially available OES with an osmolarity of approximately 315 mOsm/kg and a pH of approximately 4.3.FDA DailyMed An… Key components of an effective OES are osmolality, sodium concentration, alkalinizing agent content (effective strong ion difference), and energy content — all of which influence abomasal emptying rate and the rate of sodium delivery to the small intestine.Frontiers in Ve…
Severe dehydration — defined as a calf that is recumbent, comatose, or in shock — requires IV fluid therapy; OES is contraindicated in this state because oral therapy is too slow.FDA DailyMed An… Four crystalloid solutions are recommended for IV use in dehydrated calves: lactated Ringer's solution and acetated Ringer's solution for dehydrated calves without severe acidosis; isotonic (1.3%) or hypertonic (5.0% or 8.4%) sodium bicarbonate for calves with diarrhea and severe metabolic acidosis with hyponatremia; and hypertonic NaCl (7.2%) followed by an OES or water load for rapid resuscitation.Frontiers in Ve… Of note, 0.9% NaCl, Ringer's solution, and 5% dextrose are equally acidifying, while lactated Ringer's and acetated Ringer's are neutral to mildly acidifying — neither is optimized for neonatal calves.Frontiers in Ve…
Hydration status is best estimated by measuring the magnitude of eye recession, duration of skin tenting in the lateral neck region, and urine specific gravity by refractometry.Frontiers in Ve…
Antimicrobial therapy is indicated for bacterial scours (E. coli, Salmonella) and systemic illness, but OES products such as Re-Sorb contain no antibacterial agents.FDA DailyMed An… Antimicrobial and other ancillary therapy is warranted in calves showing systemic illness.Journal of Dair… One documented treatment protocol for a systemically ill calf used ceftiofur hydrochloride (2.2 mg/kg SC q24h), penicillin G procaine (22,000 U/kg IM q12h), and flunixin meglumine (1.1 mg/kg IV q12h) alongside fluid therapy.Journal of the…
OES should not be continued as the sole nutritional source beyond the recommended treatment period — milk or milk replacer must be added to prevent nutritional deficiency.FDA DailyMed An…
| Dehydration Grade | Fluid Choice | Route | Key Caveat |
|---|---|---|---|
| Mild–moderate | OES (e.g., Re-Sorb; ~315 mOsm/kg) | Oral | Not for recumbent/comatose calves |
| Severe with metabolic acidosis | 1.3%, 5.0%, or 8.4% sodium bicarbonate | IV | Strongly alkalinizing; use for confirmed acidosis/hyponatremia |
| Severe, rapid resuscitation | 7.2% hypertonic NaCl + OES/water load | IV then oral | Follow with oral electrolytes after IV bolus |
| Dehydrated, no severe acidosis | Lactated Ringer's or acetated Ringer's | IV | Neither solution is optimized for neonatal calves |
| Bacterial scours with systemic signs | Antimicrobials + fluids | Per drug | OES contains no antibacterial agents |
Would you like guidance on how to assess and score dehydration grade at the bedside to select the appropriate fluid tier?