Intravenous fluid therapy of calves

Plasma amino acid abnormalities in calves with diarrhea

Since few studies have been published investigating plasma amino acid abnormalities in calves with illnesses, the aim of this study was to examine plasma amino acid abnormalities in calves with diarrhea. Forty-three Holstein calves aged 10.9 ± 5.6 days old were used for this study. Thirty-one of the 43 calves exhibited clinical signs of diarrhea without severe acidemia. The other 12 healthy calves were used as the control. Concentrations of plasma essential amino acids, non-essential amino acids, branched-chain amino acids, glucogenic amino acids, and ketogenic amino acids in diarrheic calves with hypoaminoacidemia were significantly lower than those in healthy calves. No significant differences were observed between diarrheic calves with normoaminoacidemia and healthy calves when looking at these parameters.

Hypoglycemia and failure of respiratory compensation are risk factors for mortality in diarrheic calves in Hokkaido, northern Japan

The aim of present study was to identify risk factors among laboratory findings for mortality in calves with diarrhea. A retrospective analysis was conducted utilizing medical records of 221 diarrheic calves (10.4 ± 3.7 days old) with no concurrent severe disorders that were treated with intravenous fluid therapy from the initial examination. Thirty-eight of the diarrheic calves (17.2%) died within 35 days from the initial examination. Multivariate logistic regression analysis indicated that hypoglycemia (OR 3.09; 95% CI 1.22–7.87; P=0.02) and failure of respiratory compensation (OR 2.63; 95% CI 1.05–6.62; P=0.04) were the major risk factors associated with a negative outcome in diarrheic calves. According to the Kaplan-Meyer analysis, diarrheic calves with hypoglycemia and/or failure of respiratory compensation had a significantly shorter survival than calves without these factors.

Small volume resuscitation with hypertonic sodium chloride solution in cattle undergoing surgical correction of abomasal volvulus

A randomized clinical trial was conducted to compare the efficacy of rapid intravenous (IV) infusion of a 7.2% hypertonic saline solution with that of continuous application of an isotonic solution in stabilizing the circulation of cows with abomasal volvulus. Cattle treated with hypertonic saline had a significantly greater reduction in volume deficit within the first 10 min of therapy than cows treated with isotonic saline (from 5.9 ± 4.8 to 2.1 ± 4.4 L/100 kg vs. 7.0 ± 4.5 to 4.9 ± 3.8 L/100 kg, respectively). The central venous pressure (CVP) of the cows given the hypertonic saline rose within the first 10 min of therapy from 7.3 ± 3.5 to 10.8 ± 3.4 cm H2O, while the CVP of the cattle treated with isotonic saline did not increase significantly during this time. Sixty minutes after the start of the infusion, the CVP of the isotonic group was still significantly lower than that of the hypertonic group (9.5 ± 2.1 vs. 10.3 ± 3.3 cm H2O, respectively). Within the first 60 min, the base excess decreased from 5.5 ± 6.9 to 4.7 ± 6.2 mmol/L in the hypertonic group whereas it increased from 5.6 ± 5.7 to 6.8 ± 5.4 mmol/L in the isotonic group. These results suggest that for cows with abomasal volvulus, IV therapy with hypertonic saline may improve the haemodynamic and circulatory situation considerably faster and more effectively than continuous infusion with isotonic saline.

Intravenous hypertonic saline solution (7.5%) and oral electrolytes to treat of calves with noninfectious diarrhea and metabolic acidosis

Objective

The aim of this study was to compare the efficacy of treating osmotic diarrhea and dehydration in calves with hypertonic saline solution (HSS) IV, isotonic electrolyte solution (IES) PO, and a combination of these 2 solutions (HSS + IES).

Experimental Design

Eighteen male calves 8–30 days of age were used to evaluate the efficacy of 3 methods of fluid therapy after induction of osmotic diarrhea and dehydration. The diarrhea and dehydration were induced by administration of saccharose, spironolactone, and hydrochlorothiazide for 48 hours. The animals were randomly divided into 3 experimental groups: Group 1: 7.2% hypertonic saline solution‐HSS (5 mL/kg IV); Group 2: oral isotonic electrolyte solution IES (60 mL/kg PO); or Group 3: HSS+IES. Clinical signs and laboratory finding observed 48 hours post‐induction (Time 0) included diarrhea, dehydration, lethargy, and metabolic acidosis.

Results

Calves treated with HSS + IES experienced decreases in hematocrit, total protein concentration, albumin concentration, urea nitrogen concentration, and plasma volume as well as increases in blood pH, blood bicarbonate concentration, and central venous pressure between 1 and 3 hours post‐treatment. These findings also were observed in animals treated with IES, however, at a slower rate than in the HSS + IES‐treated animals. Animals treated with HSS continued to display signs of dehydration, lethargy, and metabolic acidosis 24 hours post‐treatment.

Conclusion

Treatment with a combination of HSS and IES produced rapid and sustainable correction of hypovolemia and metabolic acidosis in calves with noninfections diarrhea and dehydration.

Importance of the effective strong ion difference of an intravenous solution in the treatment of diarrheic calves with naturally acquired acidemia and strong ion (metabolic) acidosis

BACKGROUND

The effect of sodium bicarbonate on acid-base balance in metabolic acidosis is interpreted differently by Henderson-Hasselbalch and strong ion acid-base approaches. Application of the traditional bicarbonate-centric approach indicates that bicarbonate administration corrects the metabolic acidosis by buffering hydrogen ions, whereas strong ion difference theory indicates that the co-administration of the strong cation sodium with a volatile buffer (bicarbonate) corrects the strong ion acidosis by increasing the strong ion difference (SID) in plasma.

OBJECTIVE

To investigate the relative importance of the effective SID of IV solutions in correcting acidemia in calves with diarrhea.

ANIMALS

Twenty-two Holstein-Friesian calves (4-21 days old) with naturally acquired diarrhea and strong ion (metabolic) acidosis.

METHODS

Calves were randomly assigned to IV treatment with a solution of sodium bicarbonate (1.4%) or sodium gluconate (3.26%). Fluids were administered over 4 hours and the effect on acid-base balance was determined.

RESULTS

Calves suffered from acidemia owing to moderate to strong ion acidosis arising from hyponatremia and hyper-D-lactatemia. Sodium bicarbonate infusion was effective in correcting the strong ion acidosis. In contrast, sodium gluconate infusion did not change blood pH, presumably because the strong anion gluconate was minimally metabolized.

CONCLUSIONS

A solution containing a high effective SID (sodium bicarbonate) is much more effective in alkalinizing diarrheic calves with strong ion acidosis than a solution with a low effective SID (sodium gluconate). Sodium gluconate is ineffective in correcting acidemia, which can be explained using traditional acid-base theory but requires a new parameter, effective SID, to be understood using the strong ion approach.

Development of a diagnostic diagram for rapid field assessment of acidosis severity in diarrheic calves

OBJECTIVE

To develop a diagnostic diagram for rapid field assessment of acidosis severity in diarrheic calves.

DESIGN

Prospective cross-sectional study.

ANIMALS

148 Piedmontese calves (38 calves in preliminary experiments; 83 diarrheic calves and 27 healthy control calves in the primary experiment).

PROCEDURES

Physical examination was performed and a standard data collection form was completed for each calf. Blood samples were obtained and submitted for evaluation of acid-base balance, performance of a CBC, and measurement of electrolyte and total protein concentrations.

RESULTS

Severe metabolic acidosis (extracellular base excess more negative than -10 mmol/L) was associated with abnormal mental status, delayed or absent suckle reflex, abnormal posture or gait, enophthalmos, and cold oral mucosal membranes. Clinical signs associated with severe metabolic acidosis were arranged into a grid to create a diagnostic diagram. Sensitivity and specificity of the diagnostic diagram for the prediction of severe metabolic acidosis were 88% and 79%, respectively.

CONCLUSIONS AND CLINICAL RELEVANCE

Use of the diagnostic diagram may aid differentiation between severe and nonsevere acidosis patterns as determined on the basis of clinical signs.

Comparison of the effects of intravenous administration of isotonic and hypertonic sodium bicarbonate solutions on venous acid-base status in dehydrated calves with strong ion acidosis

OBJECTIVE-To compare the effects of IV administration of isotonic (1.3%) and hypertonic (8.4%) sodium bicarbonate (NaHCO(3)) solutions on acid-base status in dehydrated calves with strong ion (metabolic) acidosis. DESIGN-Randomized controlled clinical trial. ANIMALS-50 calves with diarrhea and severe dehydration. PROCEDURES-Calves were randomly assigned to receive isotonic NaHCO(3) solution (65 mL/kg [29.5 mL/lb], IV) over 3 hours (n = 30) or hypertonic NaHCO(3) solution (10 mL/kg [4.5 mL/lb], IV) over 20 minutes (20). Blood samples were collected at 0 hours (immediately prior to solution administration) and at 0.5, 1, 2, and 4 hours after administration began. Samples were submitted for blood gas analysis, serum biochemical analysis, and determination of blood Na(+), K(+), and Cl(-) concentrations and percentage change in plasma volume. RESULTS-Calves that received isotonic NaHCO(3) solution had an increase in venous blood pH, HCO(3) concentration, and base excess; a small, transient increase in Po(2); and no change in Pco(2) within 4 hours after administration began. Calves that received hypertonic NaHCO(3) solution had an immediate increase in venous blood pH, HCO(3) concentration, and base excess; a small, transient increase Pco(2); and no change in Po(2) within 0.5 hours after treatment began. Plasma volume increased to a greater extent following administration of isotonic solution than after administration of hypertonic solution. CONCLUSIONS AND CLINICAL RELEVANCE-IV administration of 8.4% NaHCO(3) solution in small volumes provided fast and effective improvement of severe acid-base abnormalities in calves with severe strong ion acidosis but did not improve hydration status as well as administration of a larger volume of isotonic NaHCO(3) solution.

Bovine coronavirus associated syndromes

Bovine coronaviruses, like other animal coronaviruses, have a predilection for intestinal and respiratory tracts. The viruses responsible for enteric and respiratory symptoms are closely related antigenically and genetically. Only 4 bovine coronavirus isolates have been completely sequenced and thus, the information about the genetics of the virus is still limited. This article reviews the clinical syndromes associated with bovine coronavirus, including pneumonia in calves and adult cattle, calf diarrhea, and winter dysentery; diagnostic methods; prevention using vaccination; and treatment, with adjunctive immunotherapy.

Comparison of the alkalizing effects of bicarbonate precursors in calves with experimentally induced metabolic acidosis

The aims of this study were to confirm whether commercial acetated Ringer's solution, which contains 28 mM of sodium acetate, is superior to commercial lactated Ringer's solution in alkalizing effects in calves with experimentally induced metabolic acidosis. Twenty calves with experimentally induced mild acidosis were intravenously administered isotonic saline, DL-lactated, L-lactated or acetated Ringer's solution at a dose of 80 ml/kg body weight (BW). The acetated Ringer's solution induced a significantly greater increase in venous HCO(3)(-) and base excess concentrations than the other fluids during the early phases of extracellular fluid replacement in mild metabolic acidosis. Therefore, the alkalizing effect of commercial acetated Ringer's solution is superior to commercial DL- and L-lactated Ringer's solution in treatment of mild metabolic acidosis in calves.

Treatment of calf diarrhea: intravenous fluid therapy

Severely dehydrated calves that are unable to suckle need intravenous fluids for effective resuscitation. Intravenous fluid therapy is also indicated for sick calves without obvious dehydration, such as calves with strong ion acidosis, ruminal acidosis (rumen drinkers), severe pneumonia, septicemia, or hypothermia. This article presents an updated overview of intravenous fluid therapy for calves, recent insights into the development of metabolic acidosis in young calves resulting from accumulation of D-lactate, a simplified algorithm for intravenous fluid therapy, and a procedure for ear vein catheterization under field conditions.

Clinical efficacy of intravenous hypertonic saline solution or hypertonic bicarbonate solution in the treatment of inappetent calves with neonatal diarrhea

Background: The clinical efficacy of IV administered hypertonic saline solution and hypertonic bicarbonate solution (HBS) in the treatment of inappetent diarrheic calves has not been compared yet.

Hypothesis: HBS is more advantageous than hypertonic saline in the treatment of calves with severe metabolic acidosis.

Animals: Twenty‐eight dehydrated, inappetent calves with neonatal diarrhea.

Methods: In 2 consecutive clinical studies, calves were initially treated with saline (5.85%; 5 mL/kg body weight [BW] over 4 minutes; study I: N = 16) or bicarbonate solution (8.4%; 10 mL/kg BW over 8 minutes; study II: N = 12), respectively, followed by oral administration of 3 L isotonic electrolyte solution 5 minutes after injection. Clinical and laboratory variables were monitored for 72 hours.

Results: Treatment failed in 6 calves of study I and in 1 calf of study II as indicated by a deterioration of the general condition. All treatment failures had more severe metabolic acidosis compared with successfully treated calves before treatment. In the latter, rehydration was completed within 18 hours after injection; metabolic acidosis was corrected within 24 hours (study I) and 6 hours (study II) after injection.

Conclusions and Clinical Importance: Diarrheic calves with slight metabolic acidosis (base excess [BE] >−10 mM) can be treated successfully with hypertonic saline. HBS is appropriate in calves without respiratory problems with more severe metabolic acidosis (BE up to −20 mM). Intensive care of the calves is required to ensure a sufficient oral fluid intake after the initial IV treatment.

Disease management of dairy calves and heifers

This article focuses on the most important diseases of dairy calves and heifers and presents clinical approaches that can improve detection, diagnosis, and treatment of herd-based problems. A systematic herd investigation strategy is pivotal to define the problems, understand important risk factors, develop a plan, and make recommendations for disease management accurately. A review of records, colostrum and feeding routines, housing and bedding management, routine procedures, vaccination, and treatment protocols begins the investigation and determines which diagnostic procedures and testing strategies are most useful. Disease management is most effective when the problem source is well defined and the exposure can be limited, calf immunity can be enhanced, or a combination of both. Screening examinations performed regularly or done at strategic time points improves detection of disease, can be used to monitor treatment outcomes, and can avoid disease outbreaks.

Relationship between depression score and acid-base status in Japanese Black calves with diarrhea

We evaluated the relationship between depression score and acid-base status in 84 purebred and crossbred Japanese Black calves. The bicarbonate (p<0.001) and base excess concentrations (p<0.001) were significantly and negatively correlated with the depression scores of the calves. The proposed diagnostic cutoff point for a depression score that indicates severe metabolic acidosis (BE < -10 mM) is 6.5 based on analysis of the ROC curve. The sensitivity and specificity were 88.4% and 81.2%, respectively. The depression scoring system is a useful tool for evaluation of the acid-base status of purebred and crossbred Japanese Black calves. In addition, a depression score of 6.5 suggests severe metabolic acidosis and that intravenous infusion of sodium bicarbonate solution is necessary.

Effects of hypertonic sodium bicarbonate solution on electrolyte concentrations and enzyme activities in newborn calves with respiratory and metabolic acidosis

OBJECTIVE

To determine concentrations of electrolytes, total bilirubin, urea, creatinine, and hemoglobin; activities of some enzymes; and Hct and number of leukocytes and erythrocytes of newborn calves in relation to the degree of acidosis and treatment with a hypertonic sodium bicarbonate (NaHCO(3)) solution.

ANIMALS

20 acidotic newborn calves with a blood pH < 7.2 and 22 newborn control calves with a blood pH > or = 7.2.

PROCEDURES

Approximately 10 minutes after birth, acidotic calves were treated by IV administration of 5% NaHCO(3) solution. The amount of hypertonic solution infused was dependent on the severity of the acidosis.

RESULTS

Treatment resulted in a significant increase in the mean +/- SEM base excess from -8.4 +/- 1.2 mmol/L immediately after birth to 0.3 +/- 1.1 mmol/L 120 minutes later. During the same period, sodium concentration significantly increased from 145.3 +/- 0.8 mmol/L to 147.8 +/- 0.7 mmol/L. Mean chloride concentration before NaHCO(3) administration was significantly lower in the acidotic calves (99.6 +/- 1.1 mmol/L) than in the control calves (104.1 +/- 0.9 mmol/L). Calcium concentration in acidotic calves decreased significantly from before to after treatment. Concentrations of potassium, magnesium, and inorganic phosphorus were not affected by treatment.

CONCLUSIONS AND CLINICAL RELEVANCE

Administration of hypertonic NaHCO(3) solution to acidotic neonatal calves did not have any adverse effects on plasma concentrations of several commonly measured electrolytes or enzyme activities. The treatment volume used was smaller, compared with that for an isotonic solution, which makes it more practical for use in field settings.

Enteral fluid therapy in large animals

Enteral fluids administered alone, or in conjunction with intravenous fluids, are reported to be useful for the treatment of dehydration and electrolyte loss associated with diarrhoea in a number of species, following exercise in horses and for feed impaction of the large intestine of horses. Enteral fluids are suitable for treatment of mild to moderately dehydrated patients with some intact intestinal epithelium and motile small intestine. In patients that will drink voluntarily or tolerate nasal intubation the use of enteral fluids may avoid the complications associated with intravenous fluid administration. However the labour costs associated with repeated nasal intubation in intensively managed patients requiring large volumes of fluids may make the use of enteral fluids less economical than intravenous fluid administration. Enteral fluid use alone is contraindicated in patients that are severely dehydrated and/or in hypovolaemic shock, however, if used in conjunction with intravenous fluids, the effects of villous atrophy and malnutrition may be ameliorated and the duration of hospitalisation shortened. There is a variety of commercially available enteral fluids available to veterinary practitioners. While the key components of these fluids are sodium, chloride and carbohydrates, the amounts of ions and other ingredients such as potassium, alkalising agents, amino acids and shortchain fatty acids may vary. The species of the animal, the underlying condition, and the constituents of the fluid, should influence the choice of an enteral fluid.

Fluid and electrolyte therapy in ruminants

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.

Effects of intravenous infusion of hypotonic lactated Ringer's solution on calves with diarrhea

The effects of intravenous infusion of hypotonic lactated Ringer's (LR: n=14) on plasma volume and venous blood gases were compared to those of hypotonic Ringer's solutions (RS: n=7) in diarrheic Japanese Black breed calves with metabolic acidosis. Venous blood samples were collected immediately before and after, and at 24 hr after the fluid infusion therapy. The LR and RS infusions increased relative plasma volume to 147.1 +/- 25.5% and 134.2 +/- 18.6%, respectively, just after the fluid therapy. The LR infusion induced an increase in the BE value (+5.1 +/- 4.8 mM) at 24 hr compared to that of RS. LR infusion should be explored as a treatment for dehydration and moderate metabolic acidemia caused by naturally occurring diarrhea in calves.

Comparison of the Effects of Isotonic and Hypertonic Sodium Bicarbonate Solutions on Acidemic Calves Experimentally Induced by Ammonium Chloride Administration

The objectives of this study were to evaluate and compare the effects of intravenously (IV) administered infusion of isotonic solution (ISB) or hypertonic sodium bicarbonate solution (HSB) on acid-base equilibrium and the plasma osmolarity in acidemic calves experimentally induced by 5 M-NH(4)Cl, IV infusion (1.0 ml/kg, over 1 hr). The ISB and HSB infusion induced progressive and significant increases in their HCO(3)(-) and BE levels that persisted throughout the period of fluid administration. The plasma osmolarity in the ISB groups was significantly decreased. The plasma osmolarity in the HSB group was significantly higher than in the calves in the other groups (p<0.05). ISB solution might be safe and effective for treating and reviving conscious calves from experimentally induced metabolic acidosis.

Effect of intravenous infusion of isotonic sodium bicarbonate solution on acidemic calves with diarrhea

The effect of 1.35% isotonic sodium bicarbonate solution (ISB) administered intravenously on acid-base equilibrium was examined in 18 acidemic Japanese black beef calves with spontaneous diarrhea. The infusion volumes of ISB were decided based on the first half volumes of base needed. In 72.2% (13/18) of calves, improvement of acidemia was detected. There was good correlation (r=0.693, p<0.01) between infused volume of ISB and changes in base excess (y=1.097x + 4.762). Infusion volumes of ISB were 7.5, 10.2, 12.9 and 15.7 ml/kg, respectively, enough to correcting the first half of 5, 10, 15 and 20 mEq/l of base deficit in acidemic calves. Our finding suggested that ISB could be used to correct metabolic acidosis without altering electrolyte concentrations in calves.

Evaluation of isotonic sodium bicarbonate solution for alkalizing effects in conscious calves

After intravenous (i.v.) infusion of various volumes of 1.35%-isotonic sodium bicarbonate solution (ISB), acid-base equilibrium, blood pressure, plasma volume and biochemical parameters in healthy Holstein calves were studied. Four calves each were randomly assigned to the low-dose (LD; i.v. infusion of 5 ml/kg ISB), middle-dose (MD; i.v. infusion of 10 ml/kg ISB) and the high-dose groups (HD; i.v. infusion of 15 ml/kg ISB). Administration volumes of ISB in the LD, MD and HD groups were decided based on the first half volumes of 5, 10 and 15 mEq of base requirement by the acceptable equation. Systemic, pulmonary artery and central venous pressures, cardiac output and plasma osmotic pressure were not changed by ISB infusion and remained constant throughout the experiment for all groups. There was good correlation (r(2) = 0.950) between relative changes in base excess and infused volume of bicarbonate (y=2.491x). The coefficient of distribution for bicarbonate ions was calculated to be 0.401 (=1/2.491). Therefore, it is suggested that a value of 0.4 would be most appropriate when calculating the base requirements in calves. Therefore, the first half volumes of ISB correcting base deficits of 5, 10 and 15 mEq in calves were estimated to be 6, 12 and 18 ml/kg, respectively. On the basis of the findings in this study, ISB may be used to correct metabolic acidosis without altering the plasma osmotic pressure, hemodynamic status and respiratory function in the calves.

Effect of isotonic and hypotonic lactated ringer's solutions with dextrose intravenously administered to dehydrated heifers

To determine the effects of rapid infusion of essential fluids in a volume of hypotonic lactated Ringer's solution, the central venous pressure (CVP) and acid-base equilibrium were investigated in to mildly dehydrated heifers. Mild dehydration was induced in 9 Holstein heifers by withholding food and water until 7.0+/-5.7% of plasma volume had been lost. The heifers were randomly assigned to the ILG (lactated Ringer's + 5% dextrose), HLG (1/2 lactated Ringer's + 2.2% dextrose) or HRG (1/2 Ringer's + 2.5% dextrose) groups with 3 heifers in each group. Heifers received 30 ml/kg of one of the fluids, at a flow rate of 20 ml/kg/hr. The rapid intravenous (IV) infusions of HLG and HRG used in this study were found to be safe and effective in increasing plasma volume without increasing CVP, even though the infusion was given to the jugular vein at a dosage of 30 ml/kg. However, ILG infusion induced progressive increases in CVP, reaching 9.0+/-2.0 mmHg. No clinical signs, such as moist rales on auscultation, moist cough, jugular vein congestion, ophthalmoptosis, salivation or arrhythmia, were observed throughout the fluid infusion. The relative changes in base excess (rBE) for the ILG and HRG groups were significantly decreased until the end of fluid infusion. As for the HLG group, rBE slightly decreased until the end of the fluid infusion. Then the values significantly increased and exceeded the pre-infusion value at the end of the experiment. While IV infusion of HLG inhibited acidification caused by dilution, HRG infusion induced diluted acidification. It is suggested that HLG infusion should be examined as a treatment for cattle with dehydration and moderate metabolic acidosis, since rapid infusion of HLG may be more beneficial for rehydrating cattle with metabolic acidosis than current treatment.