Kevin A. Hahn

Multicenter veterinary practice assessment of the effects of omega-3 fatty acids on osteoarthritis in dogs

OBJECTIVE To assess the effect of food containing high concentrations of fish oil omega-3 fatty acids and a low omega-6-omega-3 fatty acid ratio on clinical signs of osteoarthritis in dogs. DESIGN Randomized, double-blinded, controlled clinical trial. ANIMALS 127 client-owned dogs with osteoarthritis in 1 or more joints from 18 privately owned veterinary clinics. PROCEDURES Dogs were randomly assigned to be fed for 6 months with a typical commercial food or a test food containing a 31-fold increase in total omega-3 fatty acid content and a 34-fold decrease in omega-6-omega-3 ratio, compared with the control food. Dog owners completed a questionnaire about their dogs arthritic condition, and investigators performed a physical examination and collected samples for a CBC and serum biochemical analyses (including measurement of fatty acids concentration) at the onset of the study and at 6, 12, and 24 weeks afterward. RESULTS Dogs fed the test food had a significantly higher serum concentration of total omega-3 fatty acids and a significantly lower serum concentration of arachidonic acid at 6, 12, and 24 weeks. According to owners, dogs fed the test food had a significantly improved ability to rise from a resting position and play at 6 weeks and improved ability to walk at 12 and 24 weeks, compared with control dogs. CONCLUSIONS AND CLINICAL RELEVANCE Ingestion of the test food raised blood concentrations of omega-3 fatty acids and appeared to improve the arthritic condition in pet dogs with osteoarthritis.

A multicenter study of the effect of dietary supplementation with fish oil omega-3 fatty acids on carprofen dosage in dogs with osteoarthritis.

OBJECTIVE To determine the effects of feeding a diet supplemented with fish oil omega-3 fatty acids on carprofen dosage in dogs with osteoarthritis. DESIGN Randomized, controlled, multisite clinical trial. ANIMALS 131 client-owned dogs with stable chronic osteoarthritis examined at 33 privately owned veterinary hospitals in the United States. PROCEDURES In all dogs, the dosage of carprofen was standardized over a 3-week period to approximately 4.4 mg/kg/d (2 mg/lb/d), PO. Dogs were then randomly assigned to receive a food supplemented with fish oil omega-3 fatty acids or a control food with low omega-3 fatty acid content, and 3, 6, 9, and 12 weeks later, investigators made decisions regarding increasing or decreasing the carprofen dosage on the basis of investigator assessments of 5 clinical signs and owner assessments of 15 signs. RESULTS Linear regression analysis indicated that over the 12-week study period, carprofen dosage decreased significantly faster among dogs fed the supplemented diet than among dogs fed the control diet. The distribution of changes in carprofen dosage for dogs in the control group was significantly different from the distribution of changes in carprofen dosage for dogs in the test group. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that in dogs with chronic osteoarthritis receiving carprofen because of signs of pain, feeding a diet supplemented with fish oil omega-3 fatty acids may allow for a reduction in carprofen dosage.

Dose‐Titration Effects of Fish Oil in Osteoarthritic Dogs

BACKGROUND Food supplemented with fish oil improves clinical signs and weight bearing in dogs with osteoarthritis (OA). OBJECTIVE Determine whether increasing the amount of fish oil in food provides additional symptomatic improvements in OA. ANIMALS One hundred and seventy-seven client-owned dogs with stable chronic OA of the hip or stifle. METHODS Prospective, randomized clinical trial using pet dogs. Dogs were randomly assigned to receive the baseline therapeutic food (0.8% eicosopentanoic acid [EPA] + docosahexaenoic acid [DHA]) or experimental foods containing approximately 2- and 3-fold higher EPA+DHA concentrations. Both veterinarians and owners were blinded as to which food the dog received. On days 0, 21, 45, and 90, serum fatty acid concentrations were measured and veterinarians assessed the severity of 5 clinical signs of OA. At the end of the study (day 90), veterinarians scored overall arthritic condition and progression of arthritis based on their clinical signs and an owner interview. RESULTS Serum concentrations of EPA and DHA rose in parallel with food concentrations. For 2 of 5 clinical signs (lameness and weight bearing) and for overall arthritic condition and progression of arthritis, there was a significant improvement between the baseline and 3X EPA+DHA foods (P=.04, .03, .001, .0008, respectively) but not between the baseline and the 2X EPA+DHA foods. CONCLUSIONS AND CLINICAL IMPORTANCE Increasing the amount of fish oil beyond that in the baseline food results in dose-dependent increases in serum EPA and DHA concentrations and modest improvements in the clinical signs of OA in pet dogs.

Effect of feeding a weight loss food beyond a caloric restriction period on body composition and resistance to weight gain in dogs

OBJECTIVE To determine the effect of feeding a food with coconut oil and supplemental L-carnitine, lipoic acid, lysine, leucine, and fiber on weight loss and maintenance in dogs. DESIGN Prospective clinical study. ANIMALS 50 overweight dogs. PROCEDURES The study consisted of 2 trials. During trial 1, 30 dogs were allocated to 3 groups (10 dogs/group) to be fed a dry maintenance dog food to maintain body weight (group 1) or a dry test food at the same amount on a mass (group 2) or energy (group 3) basis as group 1. During trial 2, each of 20 dogs was fed the test food and caloric intake was adjusted to maintain a weight loss rate of 1% to 2%/wk (weight loss phase). Next, each dog was fed the test food in an amount calculated to maintain the body weight achieved at the end of the weight loss phase (weight maintenance phase). Dogs were weighed and underwent dual-energy x-ray absorptiometry monthly. Metabolomic data were determined before (baseline) and after each phase. RESULTS During trial 1, dogs in groups 2 and 3 lost significantly more weight than did those in group 1. During trial 2, dogs lost a significant amount of body weight and fat mass but retained lean body mass (LBM) during the weight loss phase and continued to lose body fat but gained LBM during the weight maintenance phase. Evaluation of metabolomic data suggested that fat metabolism and LBM retention were improved from baseline for dogs fed the test food. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that feeding overweight dogs the test food caused weight loss and improvements in body condition during the weight-maintenance phase, possibly because the food composition improved energy metabolism.

Analysis of lomustine drug content in FDA-approved and compounded lomustine capsules

OBJECTIVE To determine the lomustine content (potency) in compounded and FDA-approved lomustine capsules. DESIGN Evaluation study. SAMPLE 2 formulations of lomustine capsules (low dose [7 to 11 mg] and high dose [40 to 48 mg]; 5 capsules/dose/source) from 3 compounders and from 1 manufacturer of FDA-approved capsules. PROCEDURES Lomustine content was measured by use of a validated high-pressure liquid chromatography method. An a priori acceptable range of 90% to 110% of the stated lomustine content was selected on the basis of US Pharmacopeia guidelines. RESULTS The measured amount of lomustine in all compounded capsules was less than the stated content (range, 59% to 95%) and was frequently outside the acceptable range (failure rate, 2/5 to 5/5). Coefficients of variation for lomustine content ranged from 4.1% to 16.7% for compounded low-dose capsules and from 1.1% to 10.8% for compounded high-dose capsules. The measured amount of lomustine in all FDA-approved capsules was slightly above the stated content (range, 104% to 110%) and consistently within the acceptable range. Coefficients of variation for lomustine content were 0.5% for low-dose and 2.3% for high-dose FDA-approved capsules. CONCLUSIONS AND CLINICAL RELEVANCE Compounded lomustine frequently did not contain the stated content of active drug and had a wider range of lomustine content variability than did the FDA-approved product. The sample size was small, and larger studies are needed to confirm these findings; however, we recommend that compounded veterinary formulations of lomustine not be used when appropriate doses can be achieved with FDA-approved capsules or combinations of FDA-approved capsules.