Objective—To assess effects of foods fortified with docosahexaenoic acid (DHA)–rich fish oil on cognitive, memory, psychomotor, immunologic, and retinal function and other measures of development in healthy puppies.
Animals—48 Beagle puppies.
Procedures—Puppies were assigned to 3 groups after weaning (n = 16/group) and received 1 of 3 foods (low-DHA, moderate-DHA, or high-DHA food) as their sole source of nutrition until 1 year of age. Visual discrimination learning and memory tasks, psychomotor performance tasks, and physiologic tests including blood and serum analysis, electroretinography, and dual-energy x-ray absorptiometry were performed at various time points. Anti-rabies virus antibody titers were evaluated 1, 2, 4, and 8 weeks after vaccination at 16 weeks of age.
Results—Foods had similar proximate analysis results but varied in concentration of DHA from fish oil; the high-DHA food also contained higher concentrations of vitamin E, taurine, choline, and l-carnitine than did other foods. The high-DHA group had significantly better results for reversal task learning, visual contrast discrimination, and early psychomotor performance in side-to-side navigation through an obstacle-containing maze than did the moderate-DHA and low-DHA groups. The high-DHA group had significantly higher anti-rabies antibody titers 1 and 2 weeks after vaccination than did other groups. Peak b-wave amplitudes during scotopic electroretinography were positively correlated with serum DHA concentrations at all evaluated time points.
Conclusions and Clinical Relevance—Dietary fortification with fish oils rich in DHA and possibly other nutrients implicated in neurocognitive development following weaning improved cognitive, memory, psychomotor, immunologic, and retinal functions in growing dogs.
Objective—To determine effects of dietary n-3 fatty
acids from Menhaden fish oil on plasma α-tocopherol
concentrations in Beagles.
Animals—32 female Beagles.
Procedure—For 82 days, dogs were fed diets that contained
1 of 2 ratios of n-6:n-3 fatty acids (40:1 [low n-3]
and 1.4:1 [high n-3]) and 1 of 3 concentrations of all- rac-
α-tocopheryl acetate (low, 17 mg/kg of diet; medium,
101 mg/kg; and high, 447 mg/kg) in a 2 X 3 factorial study.
Results—Diets high in n-3 fatty acids significantly
increased total content of n-3 fatty acids in plasma
(17.0 g/100 g of fatty acids), compared with low n-3
diets (2.02 g/100 g of fatty acids). Mean ± SEM plasma
concentration of cholesterol was significantly
lower in dogs consuming high n-3 diets (4.59 ± 0.48
mmol/L), compared with dogs consuming low n-3
diets (5.71 ± 0.48 mmol/L). A significant interaction
existed between the ratio for n-6 and n-3 fatty acids
and amount of α-tocopheryl acetate in the diet (plasma
α-tocopherol concentration expressed on a molar
basis), because the plasma concentration of α-tocopherol
was higher in dogs consuming low n-3 diets,
compared with those consuming high n-3 diets, at
the 2 higher amounts of dietary α-tocopheryl
acetate. Plasma α-tocopherol concentration
expressed relative to total lipid content did not reveal
effects of dietary n-3 fatty acids on concentration of
Conclusion and Clinical Relevance—Plasma
α-tocopherol concentration is not dependent on dietary
ratio of n-6 and n-3 fatty acids when α-tocopherol concentration
is expressed relative to the total lipid content
of plasma. (Am J Vet Res 2002;63:104–110)
Objective—To determine the effect of dietary n-6 to
n-3 fatty acid ratios and α-tocopheryl acetate concentration
on immune functions and T cell subpopulations
in healthy dogs.
Animals—Thirty-two 7- to 10-year old female Beagles.
Procedure—For 17 weeks, dogs were fed food that
contained low (1.4:1) or high (40:1) ratios of n-6 to n-3
fatty acids in combination with 3 concentrations of all
rac-α-tocopheryl acetate (low, 17 mg/kg of food;
medium, 101 mg/kg; high, 447 mg/kg). Dogs were
inoculated twice with a keyhole limpet hemocyanin
suspension at 13 and 15 weeks.
Results—After 12 weeks, dogs consuming low concentrations
of α-tocopheryl acetate had lower percentages
of CD8+ T cells, compared with dogs consuming
medium or high α-tocopheryl acetate concentrations.
Also, dogs consuming low α-tocopheryl
acetate concentrations had higher CD4+ to CD8+ T
cell ratios. On day 4 of week 15, the percentage of
CD8+ T cells was highest in dogs fed medium concentrations
of α-tocopheryl acetate, compared with
other dogs; however, the CD4+ to CD8+ T cell ratio
was higher only in dogs fed low concentrations of α-
tocopheryl acetate with high concentrations of n-3
fatty acids. Dogs consuming low concentrations of n-
3 fatty acids with medium concentrations of α-tocopheryl
acetate had the largest delayed-type hypersensitivity
(DTH) skin test response.
Conclusions and Clinical Relevance—An optimum
amount of dietary α-tocopheryl acetate concentration,
regardless of the dietary n-6 to n-3 fatty acid ratio,
stimulates the CD8+ T cell population. Effects of an
optimum amount of dietary α-tocopheryl acetate concentration
on the DTH response are blunted by dietary
n-3 fatty acids. (Am J Vet Res 2003;64:762–772)
Objective—To determine the effect of feeding a food with coconut oil and supplemental l-carnitine, lysine, leucine, and fiber on weight loss and maintenance in cats.
Design—Prospective clinical study.
Animals—50 overweight cats.
Procedures—The study consisted of 2 trials. During trial 1, 30 cats were allocated to 3 groups (10 cats/group) to be fed a dry maintenance cat 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 cats was fed the test food and caloric intake was adjusted to maintain a weight loss rate of 1%/wk (weight loss phase). Next, each cat 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). Cats were weighed and underwent dual-energy x-ray absorptiometry monthly. Metabolomic data were determined before (baseline) and after each phase.
Results—During trial 1, cats in groups 2 and 3 lost significantly more weight than did those in group 1. During trial 2, cats lost a significant amount of body weight and fat mass but retained lean body mass during the weight loss phase and continued to lose body weight and fat mass but gained lean body mass during the weight maintenance phase. Evaluation of metabolomic data suggested that fat metabolism was improved from baseline for cats fed the test food.
Conclusions and Clinical Relevance—Results suggested that feeding overweight cats the test food caused weight loss and improvements in body condition during the weight maintenance phase, possibly because the food composition improved energy metabolism.
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.
Objective—To determine direct and indirect costs associated with raccoon rabies incidents involving cattle herds in Hampshire County, WV, in 2008 and Guernsey County, Ohio, in 2010.
Design—Ex post cost analysis.
Animals—1 cattle herd in Hampshire County, WV, in 2008 and 1 cattle herd in Guernsey County, Ohio, in 2010.
Procedures—Data were collected for each incident through telephone and email interviews with 16 federal, state, and county agency personnel involved in the case investigations and coordinated responses for rabies in the cattle herds. To characterize the economic impact associated with rabies in the 2 cattle herds, cost analysis was conducted with 7 cost variables (salary and benefits for personnel involved in the response, human postexposure prophylaxis, indirect patient costs, rabies diagnostic testing, cattle carcass disposal, market value of euthanized cattle, and enhanced rabies surveillance). Estimates of direct costs were determined on the basis of agency records and other relevant data obtained from notes and reports made by agency staff at the time of the incident and from a review of the literature.
Results—Primary costs included the market value of euthanized cattle ($51,461 in West Virginia; $12,561 in Ohio), human postexposure prophylaxis ($17,959 in West Virginia; $11,297 in Ohio), and salary and benefits for personnel involved in the response ($19,792 in West Virginia; $14,496 in Ohio).
Conclusions and Clinical Relevance—These results should provide a basis for better characterization of the economic impact of wildlife rabies in cattle in the United States.
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.
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 dog's 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.
Animals—38 client-owned dogs with osteoarthritis examined at 2 university veterinary clinics.
Procedures—Dogs were randomly assigned to receive a typical commercial food (n = 16) or a test food (22) containing 3.5% fish oil omega-3 fatty acids. On day 0 (before the trial began) and days 45 and 90 after the trial began, investigators conducted orthopedic evaluations and force-plate analyses of the most severely affected limb of each dog, and owners completed questionnaires to characterize their dogs' arthritis signs.
Results—The change in mean peak vertical force between days 90 and 0 was significant for the test-food group (5.6%) but not for the control-food group (0.4%). Improvement in peak vertical force values was evident in 82% of the dogs in the test-food group, compared with 38% of the dogs in the control-food group. In addition, according to investigators' subjective evaluations, dogs fed the test food had significant improvements in lameness and weight bearing on day 90, compared with measurements obtained on day 0.
Conclusions and Clinical Relevance—At least in the short term, dietary supplementation with fish oil omega-3 fatty acids resulted in an improvement in weight bearing in dogs with osteoarthritis.