Five important questions always must be asked and answered regarding fluid and
electrolyte therapy in ruminants: (1) Is
therapy needed? (2) What type of
therapy? (3) What route of administration? (4) How much should be administered? and (5) How fast should the
solution be administered? Food animal veterinarians routinely should carry the following commercially available
crystalloid solutions and have the knowledge of how to use the products appropriately:
Ringer's solution, 1.3% NaHCO3, acetated
Ringer's solution, HS (7.2% NaCl), 8% NaHCO3, 23%
calcium gluconate,
calcium-
magnesium solutions, and 50%
dextrose. Ruminants with a blood pH less than 7.20 should be treated intravenously with 1.3% or 8.0% NaHCO3, and those animals with a blood pH greater than 7.45 should be treated intravenously with
Ringer's solution. Oral
electrolyte solutions or intravenous acetated
Ringer's solution should be administered to ruminants with a blood pH greater than 7.20 but less than 7.45, and acetated
Ringer's solution is preferred to
lactated Ringer's solution. HS
solution should be administered whenever rapid
resuscitation is required.
Oral administration of
electrolyte solutions is underused in neonatal and adult ruminants. The optimal
solution for
oral administration to neonatal ruminants has a
sodium concentration between 90 and 130 mmol/L; a
potassium concentration between 10 and 20 mmol/L; a
chloride concentration between 40 and 80 mmol/L; 40 to 80 mmol/L of metabolizable (nonbicarbonate) base, such as
acetate or
propionate; and
glucose as an energy source. The optimal formulation for adult ruminants is unknown, but such a
solution should contain
sodium,
potassium,
calcium, magnesium, phosphate, and
propionate to facilitate
sodium absorption and to provide an additional source of energy to the animal. Acidemia is treated best by intravenous or
oral administration of NaHCO3. Alkalemia is treated best by
intravenous administration of
Ringer's solution and
oral administration of
chloride-rich
electrolytes such as KCl; the latter provides a physiologically more appropriate treatment than
oral administration of
vinegar or
acetic acid solutions.
Hypocalcemia is treated best by administering intravenous
calcium borogluconate solutions or oral CaCl2
gels. Hypomagnesemia is treated best by intravenous or subcutaneous administration of combined
calcium and
magnesium solutions.
Hypophosphatemia is treated best by
oral administration of feed-grade monosodium
phosphate.
Hypokalemia is treated best by
oral administration of feed-grade KCl;
hyperkalemia is treated best by
intravenous administration of 8.0% NaHCO3 or HS. The major challenges in treating fluid and
electrolyte disorders in ruminants are making treatment protocols more practical and less expensive and formulating an optimal
electrolyte solution for
oral administration to adult ruminants.