Diet makes the difference (Sponsored by Iams)

Nutritional management is a simple but powerful tool in controlling the clinical signs of atopy in dogs. A recent double-blind study compared the performance of three commercial veterinary diets in atopic dogs regarding pruritus, skin lesions, and overall atopy severity and found that diet does make a difference.

Of the three diets compared (diet A, Iams® Veterinary Formulas Skin & Coat Response™ FP; diet B, ROYAL CANIN Veterinary Diet™ Canine Hypoallergenic HP 19™; diet C, Hill's® Prescription Diet® d/d® Potato & Salmon Formula Canine), diet A was significantly more effective at managing pruritus, skin lesions, and overall atopy severity in moderately to severely atopic dogs than diet B. Dogs fed diet C did not show significant differences vs. diet A in improvement of the clinical signs.

Client education

The diets in this study varied in ingredient and nutrient composition; however, the study results of this and previous studies suggest that the dietary omega-6:omega-3 fatty acid ratio may be important in managing the clinical signs of atopy (data on file, P&G Pet Care, 2008).

Client education

Reference

1. Scott DW, Miller WH, Griffen GE. Skin immune system and allergic skin disease. In: Muller & Kirk's Small Animal Dermatology. 5th ed. Philadelphia, Pa: WB Saunders Co, 2001;543-666.

Case study: Cindy

Subject: Cindy, an 11-year-old spayed female golden retriever; adopted by the author in May 2007.

History: Cindy's previous owner put her up for adoption citing chronic dermatologic problems. Cindy's prior medical records were unattainable.

Clinical findings on initial examination: Cindy had generalized pruritis, a yeasty odor, a greasy haircoat, and bilateral otitis externa. She was alopecic over the lumbar area and tail. She also had alopecia, lichenification, and hyperpigmentation of her periocular, perineal, caudal thigh, and ventral abdominal areas.

Management: Cindy was fed a hypoallergenic diet, Eukanuba Veterinary Diets (now Iams Veterinary Formulas) Skin & Coat Response FP, and other foods and treats were eliminated. She was bathed two to three times per week using hypoallergenic shampoo and her ears were treated topically with Otomax (Schering-Plough)?once a day for three days.

Progress: After one month of feeding Response FP, Cindy started to grow hair on her lumbar area and tail. Her ears produced less discharge and her pruritis began to diminish. After four months, she had regrown all of her fur. She continues to have minor flare-ups with otitis but she is 90% better and at this point is being managed exclusively with Response FP.

Expert advice

Douglas DeBoer, DVM, DACVD, with the University of Wisconsin-Madison's School of Veterinary Medicine, discusses food allergy and a hypoallergenic diet.

The main challenge in treating atopic dermatitis is formulating a lifelong, individualized management plan for each pet based on its unique clinical picture. This usually involves a combination of treatment choices, including allergen avoidance. While challenging for most environmental allergens, food allergen avoidance is vital for pets with a food allergy component to their disease.

Because studies generally conclude that between one in eight and one in 20 pets with atopic dermatitis may also have food allergies, it is important to perform a hypoallergenic diet trial on all pets diagnosed with atopic dermatitis. A hypoallergenic diet can also be fed as a longer-term maintenance diet when a diet trial has established the presence of food allergy.

In addition to the hypoallergenic formulation, many of these diets contain specific ingredients that may help to diminish the inflammatory response in skin, augment cutaneous barrier function, or both in allergic pets, no matter the type of allergy. For example, feeding a diet that contains high levels of anti-inflammatory fatty acids to a pet with atopic dermatitis, with or without food allergy, may provide partial relief while avoiding the need for fatty acid supplementation via capsules or liquid supplements. Supplying anti-inflammatory fatty acids through the food source also guarantees client compliance with the regimen and may decrease the total monthly cost for the client.

The key point is that clients must be vigilant for the life of the pet with food allergies, not only in feeding hypoallergenic diets, but avoiding table scraps, rawhides, and conventional treats. For pets without food allergies, a therapeutic diet can still form the basis of their diet.