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Abstract

Objective—To determine the effects of 3 commercially available, orally administered electrolyte solutions (OAEs) on abomasal luminal pH and emptying rate in dairy calves, compared with the effect of orally administered milk replacer.

Design—Randomized crossover study.

Animals—6 male dairy calves (age, 12 to 31 days).

Procedures—Calves were surgically instrumented with an abomasal cannula and were administered 4 treatments in randomized order: all-milk protein milk replacer, high-glucose high-bicarbonate OAE, high-glucose high-bicarbonate OAE containing glycine, and low-glucose OAE containing acetate and propionate. Abomasal luminal pH was measured with a miniature glass pH electrode prior to treatment administration and every second afterward for 24 hours.

Results—Feeding of orally administered milk replacer resulted in a rapid increase in mean abomasal luminal pH from 1.3 to 5.8, followed by a gradual decrease to preprandial values by 8 hours afterward (mean 24-hour pH, 3.2). High-glucose high-bicarbonate OAEs caused a large and sustained increase from 1.3 to 7.5 (mean 24-hour pH, 4.1 for the solution without glycine and 3.5 for the solution with glycine). In contrast, feeding of the acetate-containing OAE was followed by only a mild and transient increase (mean 24-hour pH, 2.1); luminal pH returned to preprandial values by 3 hours after ingestion.

Conclusions and Clinical Relevance—Ingestion of a bicarbonate-containing OAE resulted in sustained abomasal alkalinization in dairy calves. Because persistently high abomasal luminal pH may facilitate growth of enteropathogenic bacteria, administration of OAEs containing a high bicarbonate concentration (> 70mM) is not recommended for calves with diarrhea.

Full access
in Journal of the American Veterinary Medical Association

SUMMARY

Data at admission and at surgery were collected on 458 cows with right displacement of the abomasum or abomasal volvulus, to derive multiple logistic regression models for predicting postsurgical outcome (productive, salvaged, or terminal). The derived models contained few and easily obtained variables. The weight associated with each variable was determined objectively. Three admission variables (heart rate, base excess, and plasma chloride concentration), and 5 surgical variables (heart rate, base excess, diagnosis, method of decompression used, and appearance of abomasal serosa) were used in the final models. Predicted outcomes that used the admission and surgical models were closely related with actual outcomes. Total correct classification for satisfactory (productive) versus unsatisfactory outcome (salvaged and terminal) was 78.2% for the admission model and 82.7% for the surgical model. Combining data on cows with productive and salvaged outcomes as satisfactory outcome, and terminal as unsatisfactory outcome, total correct classification was 90.7% for the admission model and 93.2% for the surgical model. Using predicted probabilities, the market value of productive and salvaged cows, and the medical and surgical costs, one can calculate the expected economic value of each outcome. Treatment can be justified if the sum of the expected value of productive and salvaged outcome exceeds the sum of the medical and surgical costs and the expected salvaged value of the cow that was not treated surgically.

Free access
in American Journal of Veterinary Research

SUMMARY

Renal electrolyte and net acid excretion were characterized during generation and maintenance of hypochloremic metabolic alkalosis in a ruminant model. Two phases of renal response with regard to sodium and net acid excretion were documented. An initial decrease in net acid excretion was attributable to increase in bicarbonate excretion with associated increase in sodium excretion. As the metabolic disturbance became more advanced, a second phase of renal excretion was observed in which sodium and bicarbonate excretion were markedly decreased, leading to increase in net acid excretion and development of aciduria. Throughout the metabolic disturbance, chloride excretion was markedly decreased; potassium excretion also decreased. These changes were accompanied by increase in plasma renin and aldosterone concentrations. There was apparent failure to concentrate the urine optimally during the course of the metabolic disturbance, despite increasing plasma concentration of antidiuretic hormone.

Free access
in American Journal of Veterinary Research

Summary

Radiographic and surgical findings were compared in 123 cattle suspected of having traumatic reticuloperitonitis. Radiography of the reticulum proved to be a sensitive test for detection of a foreign body (fb). An abnormal fb position on a radiograph was a good predictor of fb perforation. If an fb was fully attached to a magnet, it was unlikely to be perforating the reticular wall. When abnormal reticulum size, abnormal reticulum location, and gas shadows adjacent to the reticulum were found simultaneously on a radiograph, hepatic or perireticular abscess was likely. Reticular radiography proved to be a useful diagnostic aid in cattle suspected of having traumatic reticuloperitonitis.

Free access
in Journal of the American Veterinary Medical Association

Summary

Clinical and surgical findings in 458 dairy cows with right displacement of the abomasum or abomasal volvulus (av) were analyzed to determine the association between these variables and the outcome (productive, salvaged, or terminal) of the affected cow.

Heart rate at initial examination was higher in the salvaged and terminal groups of cows (P < 0.0001) than in the productive group. The plasma Na+ concentration was lower in the salvaged and terminal groups of cows (P < 0.0001) than in the productive group. The plasma C1 concentration was lower in the salvaged group of cows than in cows with either productive or terminal outcomes (P < 0.0001). Anion gap was significantly higher (P < 0.0001) in the salvaged and terminal groups than in cows classified as productive.

On the basis of surgical findings, cattle with right displacement of the abomasum were more likely to survive than cows with av. Cows that required fluid decompression of the abomasum via abomasotomy were less likely to survive than those in which gaseous decompression was performed. Cows with evidence of vascular compromise of the abomasal wall were less likely to survive than those with normal abomasal serosa.

Preoperative heart rate and anion gap had positive correlations with the presence of abomasal necrosis, whereas temperature, venous blood pH, plasma bicarbonate, and base excess concentrations had negative correlations.

Cows in terminal stages of av were likely to have a mixed primary acid-base disturbance, consisting of metabolic alkalosis with superimposed metabolic acidosis. These findings were highly correlated with abomasal necrosis.

Free access
in Journal of the American Veterinary Medical Association

Summary

Nine adult female sheep were each surgically fitted with an Ivan and Johnston reentrant cannula in the cranial part of the duodenum just distal to the pylorus. By diversion (loss) of abomasal outflow, this model has been shown to consistently induce hypochloremic, hypokalemic metabolic alkalosis, accompanied by hyponatremia and dehydration. Each sheep was subjected to 3 treatment trials, each preceded by a 24-hour prediversion period, and a diversion period during which a syndrome of hypochloremia (68 ± 2 mEq/L), hypokalemia, hyponatremia, and metabolic alkalosis was induced.

Development of this syndrome was attributable to losses of large amounts of acid and electrolytes in the abomasal effluent. Mean total electrolyte contents of the effluent were: Cl, 650 ± 27 mEq; Na+, 388 ± 23 mEq; and K+, 123 ± 12 mEq, with total volume loss ranging from 3.6 to 10.0 L of gastric contents and pH ranging from 3 to 5. Decreases in plasma electrolyte concentrations also can be attributed to decreased intake, because anorexia developed shortly after the onset of diversion. Electrolyte losses in urine during diversion were minimal for Cl (mean ± sem, 12.0 ± 5.1 mEq), but were greater for Na+ (124.2 ± 14.5 mEq) and K+ (185.1 ± 31.2 mEq).

Treatments consisted of 0.9% NaCl (300 mosm/L), 3.6% NaCl (1,200 mosm/L), and 7.2% NaCl (2,400 mosm/L) administered over a 2-hour period, with the administered volume determined by the estimated total extracellular fluid Cl deficit. Significant difference was not found among treatments, with all solutions resulting in return of clinicopathologic and physical variables to prediversion values within 12 hours of treatment. We concluded that rapid iv replacement of Cl, with small volumes of hypertonic saline solution, is safe and effective for correction of experimentally induced hypochloremic, hypokalemic, metabolic alkalosis in sheep.

Free access
in American Journal of Veterinary Research

SUMMARY

Five adult 40- to 50-kg female sheep were surgically fitted with a reentrant cannulae placed in the proximal part of the duodenum just distal to the pylorus. By diversion of abomasal outflow, this model has been shown to produce hypochloremic metabolic alkalosis accompanied by dehydration, hypokalemia, and hyponatremia. Each sheep was subjected to 3 separate, 12-hour iv treatment trials, in each case preceded by a control period of 48 hours, and a diversion period of 36 to 96 hours, during which a hypochloremic (Cl ≤ 60 ± 2 mEq/L) metabolic alkalosis with hypokalemia and hyponatremia was produced.

Treatment 1, consisting of 6 L of isotonic Na gluconate, was designed to replace volume without replenishing the Cl deficit. Although hydration improved, plasma Cl decreased further, and the sheep became increasingly weak and depressed. Treatment 2, consisting of 2 L of 1.8% NaCl, was designed to replace the Cl deficit without replacing total volume. Plasma Na+ and Cl concentrations returned to normal during the 12 hours of treatment; acid-base balance and plasma K+ concentrations returned to normal within 36 hours of treatment. During treatment 3 (control, no treatment), measured metabolic values changed minimally. We concluded that the iv replacement of Cl without K+ is effective in the correction of experimentally induced hypochloremic metabolic alkalosis in sheep.

Free access
in American Journal of Veterinary Research

Abstract

Objective—To determine the seroprevalence of antibody against canine influenza virus H3N8 in a group of pet dogs that participate in flyball in Pennsylvania.

Design—Serologic survey.

Animals—Dogs attending a flyball tournament in Downingtown, Pa, from November 13 to 14, 2009.

Procedures—Blood samples were collected from dogs following owner consent. Medical, travel, and activity history of the dogs for the previous 10.5 months was obtained from owners. Serum was harvested and submitted to Cornell University Diagnostic Laboratory for measurement of antibody against canine influenza virus H3N8 via hemagglutination inhibition testing.

Results—Serum samples were obtained from 100 of 256 dogs participating in the flyball event. Although 3 of the 100 (3%) samples had positive results for antibody against canine influenza, none of the associated dogs had respiratory signs of infection (eg, coughing, sneezing, or nasal or ocular discharge) in the 10.5 months prior to testing. Eleven dogs had a history of respiratory signs, but none of those dogs had antibody against canine influenza H3N8. In addition, none of the study dogs had been vaccinated against canine influenza H3N8.

Conclusions and Clinical Relevance—Although canine influenza is considered enzootic in certain areas of the country (eg, Pennsylvania or New York), this study identified a low seroprevalence in dogs considered at high risk for infection given their life conditions and geographic origins. More research is warranted to elucidate the prevalence of exposure to the H3N8 virus in competitive sporting dogs and determine whether vaccination is warranted in such dogs.

Full access
in Journal of the American Veterinary Medical Association

Summary

Effects of increased dietary chloride and reduced sodium and potassium ion concentrations on coxofemoral joint conformation, as assessed by radiography, were examined in growing dogs. Dietary electrolyte balance was quantified by dietary anion gap (dag), defined as Na+ + K+ - Cl- in milliequivalents per 100 g of food. Diets had anion gap ranging from 8 to 41 mEq/100 g of food. One hundred sixty-seven pups from 27 litters representing 5 breeds were studied during the period of rapid growth. The extent of subluxation of the femoral head was measured on radiographs, using the method of Norberg. On average, less subluxation of the femoral head (P < 0.05) was observed when diets with lower dag were fed. Differences in dag balance did not result in different rates of weight gain; therefore, the reduction in coxofemoral joint subluxation attributable to low dag was unrelated to weight gain. Norberg angles measured at 30 weeks of age were highly correlated with coxofemoral joint status at 2 years of age, as measured by the Swedish diagnostic system and the scoring system of the Orthopedic Foundation for Animals (|r| ≥ 0.70, P < 0.0002, n = 24). This diet-related improvement in coxofemoral joint subluxation would be expected, on average, to delay or mitigate the characteristic clinical and radiographic signs of hip dysplasia in growing dogs.

Free access
in American Journal of Veterinary Research

Summary

Forty-eight 8-week-old Labrador Retrievers were allotted to 2 groups of 24 dogs each; 1 group was fed ad libitum and the other group was given 25% less of the same feed until the dogs were 2 years old. Radiography of the hip joints was done when the dogs were 30, 42, 54, 78, and 104 weeks old. Subluxation was measured by the Norberg angle on radiographs made with the dog in the standard (extended limb) position. Independent of age at which the radiography was done, there was less subluxation of the femoral heads in the limit-fed dogs. Using the Swedish method of hip joint evaluation on the same radiographs, it was found that fewer dogs on limited food intake had signs of hip dysplasia.

Radiographs done when dogs were 2 years old, for all the methods used (Norberg angle in standard and frog-limb position, the Orthopedic Foundation for Animals [ofa] score, and the Swedish score), revealed less hip dysplasia (less joint subluxation and less degenerative joint disease) in the limit-fed dogs. Using the ofa method, 7 of the 24 limit-fed dogs and 16 of the 24 ad libitum-fed dogs were diagnosed as having hip dysplasia. Similarly, using the Swedish method, 5 of the 24 limit-fed dogs and 18 of the 24 ad libitum- fed dogs were diagnosed as having hip dysplasia. The food-intake-related differences were significant both for the ofa score and for the Swedish score. There was a significant correlation between the Norberg angle measured on radiographs made with the dog in the standard position when it was 30 weeks old and the result obtained when the dog was 2 years old by the ofa and Swedish methods. The findings support the clinical recommendation to avoid overfeeding of growing dogs, particularly in breeds prone to canine hip dysplasia.

Free access
in Journal of the American Veterinary Medical Association