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- Author or Editor: William S. Swecker x
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Abstract
Objective—To determine the effects of a low or high sodium (Na) diet with or without furosemide administration on plasma electrolyte concentrations and the renin-angiotensin-aldosterone system in healthy dogs.
Animals—20 healthy adult dogs.
Procedure—Dogs were randomly allotted to 4 groups of 5 dogs each as follows: dogs fed a low Na diet (0.08% Na and 0.8% chloride [Cl] on a dry matter [DM] basis); dogs fed a low Na diet with added NaCl (1.0% Na and 2.2% Cl on a DM basis); dogs fed a low Na diet and treated with furosemide (2 mg/kg of body weight, PO, q 12 h); and dogs fed a low Na diet with added NaCl and treated with furosemide. Plasma electrolyte concentrations were measured on days 0, 21, and 35. Plasma renin activity and aldosterone concentration were analyzed by use of radioimmunoassays on days 0, 21, 35, and 53.
Results—Furosemide treatment significantly decreased plasma Cl concentration and significantly increased plasma renin activity and aldosterone concentration. Dogs fed a low Na diet had significantly higher plasma renin activities and plasma aldosterone concentrations. A significant interaction between a low Na diet and furosemide administration resulted in the lowest plasma Cl concentrations, highest plasma renin activities, and highest plasma aldosterone concentrations.
Conclusions and Clinical Relevance—In healthy dogs, feeding a low Na diet and administering furosemide resulted in an additive effect on plasma Cl concentration, renin activity, and aldosterone concentration, which may be an important consideration for treating dogs with cardiac disease. (Am J Vet Res 2001;62:1793–1796)
Abstract
Objective—To determine effects of breed and supplemental administration of vitamin E and selenium (Se) during late gestation on circulating concentrations of these micronutrients in periparturient Jerseys and Holsteins.
Design—Randomized controlled clinical study.
Animals—16 Jersey and 36 Holstein cows.
Procedure—Cows were allotted to blocks on the basis of breed and expected parturition date. Cows within blocks were randomly assigned to be given vitamin E or Se parenterally 3 to 4 weeks prior to anticipated parturition in a 2 × 2 factorial design.
Results—Results of ANOVA indicated Jerseys had higher blood concentrations of Se and lower serum concentrations of vitamin E than Holsteins at the end of lactation. Jerseys had higher blood concentrations of Se than Holsteins 3 to 4 weeks prior to parturition and at parturition. Selenium administration increased blood concentrations of Se at parturition. Administration of nutrients did not affect serum concentrations of vitamin E at parturition or 2 to 3 weeks after parturition or blood concentrations of Se 2 to 3 weeks after parturition.
Conclusions and Clinical Relevance—Jerseys and Holsteins consuming rations of comparable Se content differ in blood concentrations of Se during the nonlactating period, suggesting breed-related differences in Se metabolism during late lactation and the nonlactating period. Parenteral administration of Se 3 to 4 weeks prior to anticipated parturition increased blood concentrations of Se at parturition; however, Se concentrations of both groups at parturition were considered within the reference range for clinically normal cattle. (Am J Vet Res 2000;61:1052–1056)
Abstract
Objective—To determine effects of breed and oral vitamin E supplementation during late gestation on serum vitamin E and IgG concentrations in beef cows that calved in late winter and late summer and in neonatal calves.
Animals—73 Angus and 43 Hereford primiparous and multiparous cows and their calves.
Procedure—Cows in groups that were homogeneous regarding breed and age distribution were randomly allotted to groups that were orally supplemented (n = 59) or not supplemented (57) with vitamin E beginning 30 days prior to onset of 65-day calving seasons. Supplemental vitamin E was provided in a vitamin-mineral mix offered free-choice until parturition.
Procedure—Cows that calved in late winter and were supplemented orally with vitamin E had higher serum vitamin E concentrations at calving and after calving than did unsupplemented cows; differences between groups before calving were not significant. Calves from supplemented multiparous cows had higher vitamin E concentrations than did calves from unsupplemented cows. Winter-born calves from supplemented Hereford cows had heavier 205-day adjusted weaning weights than did winter-born calves from unsupplemented Hereford cows. Supplementation did not affect vitamin E or IgG concentrations in the herd that calved in late summer and did not affect calf growth.
Conclusions and Clinical Relevance—Oral vitamin E supplementation during late gestation may be economically beneficial in certain cow-calf operations in which late-gestation cows are consuming stored forages. ( Am J Vet Res 2001;62:921–927)
Abstract
Objective—To evaluate the long-term risk of recurrence of calcium oxalate (CaOx) cystic calculi in dogs of various breeds fed 1 of 2 therapeutic diets.
Design—Retrospective cohort study.
Animals—135 dogs with a history of CaOx cystic calculi.
Procedures—Medical records for 4 referral hospitals were searched to identify dogs that had had CaOx cystic calculi removed. Owners were contacted and medical records evaluated to obtain information on postoperative diet, recurrence of signs of lower urinary tract disease, and recurrence of cystic calculi. Dogs were grouped on the basis of breed (high-risk breeds, low-risk breeds, and Miniature Schnauzers) and diet fed after removal of cystic calculi (diet A, diet B, and any other diet [diet C], with diets A and B being therapeutic diets formulated to prevent recurrence of CaOx calculi).
Results—Breed group was a significant predictor of calculi recurrence (as determined by abdominal radiography or ultrasonography), with Miniature Schnauzers having 3 times the risk of recurrence as did dogs of other breeds. Dogs in diet group A had a lower prevalence of recurrence than did dogs in diet group C, but this difference was not significant in multivariable analysis.
Conclusions and Clinical Relevance—Results indicated that Miniature Schnauzers had a higher risk of CaOx cystic calculi recurrence than did dogs of other breeds. In addition, findings suggested that diet may play a role in decreasing recurrence, but future prospective studies are needed to validate these observations.