DERMATOLOGY
Shaping the future of animal health
Cutaneous Adverse Food
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Dr Heidi Schroeder, BVSc MMedVet(Med)
Small Animal Physician
Willow Park Small Animal
Medicine Specialist Hospital,
Willow Glen, Pretoria Pretoria,
(012) 813 8009
[email protected]
CAFR is defined as an aberrant immunological response, most often to a food protein.11 Currently it is
believed that Type I (immediate, IgE mediated) hypersensitivity plays an important role in CAFR, although
this is still unproven. Type III (delayed, immune complex) and type IV (delayed, cell-mediated) hypersensitivity reactions have also been proposed.13 Gastrointestinal signs are only seen in 10 – 15 % of dogs with
CAFR.17
Non-immunologic adverse food reactions (AFRs) include food intolerance and food intoxication which
usually result in gastrointestinal signs.1, 13 Food intolerance may be due to digestive enzyme deficiencies or
idiosyncratic reactions to food additives such as colourants and preservatives and food intoxications due
to the ingestion of bacterial or fungal toxins.13
Pathogenesis
There are currently over 6000 recognised dietary allergens, which include glycoproteins, lipopolysaccharides and carbohydrates. Glycoproteins (molecular
weight of 10 – 70kDa, heat and acid stabile) are most
commonly associated with an allergic response.1 The
most important allergens implicated in CAFR cases
are beef, dairy products and wheat, followed by lamb,
In most cases the offending food source is one
that is fed often and can be part of the diet, a treat
or flavoured medication.16 Multiple sensitivities are
common – 64% of cases.6, 13 Clinical signs of antigen sensitization usually follow a long duration of
exposure – up to 2 years.15
chicken, egg, corn, fish, rice and soy.11 Food additives,
such as preservatives are very rarely documented to
cause CAFR.11
• Dogs that are allergic to beef are usually not sensitive to milk, but they should avoid liver, veal and
•
gelatin.
Dogs allergic to egg are usually [\