Cornstarch is less allergenic than corn flour in dogs and cats previously sensitized to corn

Analysis of Intestinal Microbiota and Metabolic Pathways before and after a 2-Month-Long Hydrolyzed Fish and Rice Starch Hypoallergenic Diet Trial in Pruritic Dogs

Intestinal microbiota alterations were described in allergic individuals and may improve with diets. Farmina Ultra Hypo (FUH), a hydrolyzed fish/rice starch hypoallergenic diet, is able to improve clinical signs in allergic dogs. Study objectives were to determine microbiota differences in allergic dogs before and after feeding with FUH for eight weeks. Forty skin allergic dogs were evaluated clinically before and after the diet. Unresponsive dogs were classified as canine atopic dermatitis (CAD); responsive dogs relapsing after challenge with previous foods were classified as being food reactive (AFR), and those not relapsing as doubtful (D). Sequencing of feces collected pre- and post-diet was performed, with comparisons between and within groups, pre- and post-diet, and correlations to possible altered metabolic pathways were sought. Microbiota in all dogs was dominated by Bacteroidota, Fusobacteriota, Firmicutes and Proteobacteria, albeit with large interindividual variations and with some prevalence changes after the diet. In general, bacteria producing short-chain fatty acids were increased in all samples. CAD dogs showed pre-and post-diet microbiota patterns different from the other two groups. Bacteria taxa were enriched post-diet only in the AFR group. Changes in metabolic pathways were observed mainly in the CAD group. FUH may be able to improve intestinal microbiota and thus clinical signs of skin allergy.

Hydrolyzed chicken liver used as single source of animal protein in diet and its effect on cytokines, immunoglobulins, and fecal microbiota profile of adult dogs

Dogs with food allergies and enteropathies may require hydrolyzed diets to prevent or reduce clinical signs, therefore the protein sources used in these diets must be previously characterized and evaluated in healthy dogs. This study aimed to investigate the effects of a hydrolyzed chicken liver powder-based diet (HCLP) versus a poultry by-product meal and bovine meat and bone meal-based diet (Control), on complete blood count (CBC), cytokine, immunoglobulins responses (assessed on days 0, 15, 30 and 45), and fecal microbiota (assessed on day 45) in healthy adult dogs. The CBC did not differ between diets (P>0.05), remaining within reference range. Total plasma IL-4 concentrations were decreased over time independent of the dietary treatment (P<0.001). Total plasma IgA decreased on day 30 compared to days 0 and 45 in dogs fed the control diet (P<0.001). Total plasma IgE concentrations were reduced on days 30 and 45 in dogs fed the control diet, and on days 15 vs 30 and 15 vs 45 in dogs fed HCLP diet (P = 0.001). The 16S rRNA gene sequencing showed similar species richness and abundances of phyla and genera between diets (P>0.05). β-diversity principal coordinate analysis plots demonstrated that HCLP group had a higher similarity than control. Based on our results, healthy adult dogs fed a HCLP based diet maintained normal values for hematological and immunological characteristics, and fecal microbiota after 45 days of feeding.

The usefulness of a hydrolysed fish and rice starch elimination diet for the diagnosis of adverse food reactions in cats: an open clinical trial

BACKGROUND

Diagnosis of adverse food reaction (AFR) is based on an eight week elimination diet (ED) and is confirmed by relapse upon re-challenge with the previously fed diet. Hydrolysed EDs are commonly used for this purpose.

OBJECTIVE

To evaluate the commercially available hydrolysed fish protein and rice starch ED Farmina UltraHypo (FUH) for the diagnosis of feline AFR.

ANIMALS

Thirty-two nonseasonally pruritic cats.

METHODS AND MATERIALS

Pruritus was assessed with a new dual Visual Analog Scale, lesions with the Scoring Feline Allergic Dermatitis scale and Quality of Life with a validated questionnaire on days 0 and 56. Short-acting corticosteroids or oclacitinib were permitted during the first six weeks. Cats showing 50% pruritus and/or lesional improvement were separately challenged with their prior diet, fish and rice. Cats not responding to the study diet were fed another hydrolysed diet for two months.

RESULTS

Twenty-five cats completed the ED: four dropped out due to vomiting and/or diarrhoea, one owing to low palatability and two were lost to follow-up. In 17 cats, pruritus improved by >50% and these underwent dietary challenges. Of these, nine reacted to their prior diet and/or fish and/or rice and were diagnosed with AFR, while eight did not relapse (and a diagnosis of AFR was considered to be doubtful). Of the eight cats in which pruritus did not improve, four underwent a second ED with no improvement.

CONCLUSION AND CLINICAL IMPORTANCE

FUH may be a useful ED for the diagnosis of feline AFR, even in cats reacting to fish or rice.

Serum IgE and IgG responses to dietary antigens in dogs with and without cutaneous adverse food reactions

BACKGROUND

It is suspected that many canine cutaneous adverse food reactions (CAFR) are true immunological hypersensitivities; however, few specific dietary allergens have been identified.

OBJECTIVE

To compare serum immunoglobulin (Ig)E and IgG reactivity to specific food antigens in privately owned dogs with and without CAFR.

ANIMALS

Eighteen adult dogs with nonseasonal pruritus recruited from a hospital population.

METHODS AND MATERIALS

Dogs were fed an extensively hydrolysed poultry-based diet exclusively for 12 weeks. Serum was collected at the beginning of the trial. Canine atopic dermatitis extent and severity index and pruritus Visual Analog Scale scoring were performed at the beginning and end of the trial. Immunoblotting was performed to identify IgE and/or IgG binding to specific proteins in beef, egg, milk, chicken, pork, soy and wheat extracts.

RESULTS

A CAFR (defined as an unequivocal relapse of pruritus after dietary challenge) was diagnosed in 10 dogs, with 60% relapsing when fed chicken-based diets. Binding of subjects' IgG to almost all proteins in all extracts was seen regardless of reported dietary history. Few proteins were exclusively or predominantly bound by IgE in CAFR dogs. Exceptions included a 42 kDa band (chicken), a 52 kDa band (beef), a 46 kDa band (beef and milk) and a poorly defined high molecular weight protein or proteins (beef and milk).

CONCLUSION

This study demonstrated three protein bands and a poorly defined band predominantly recognized by sera from dogs with CAFR relative to non-CAFR dog sera. Almost all proteins were bound by IgG in all dogs, suggesting prior exposure to unreported foods.

The usefulness of short-course prednisolone during the initial phase of an elimination diet trial in dogs with food-induced atopic dermatitis

BACKGROUND

Food allergy is a possible cause of atopic dermatitis (AD) in dogs; it is typically diagnosed following an eight-week elimination diet trial (EDT) and a provocation with the original diet. This lengthy procedure is difficult for owners and its interpretation may be unclear.

HYPOTHESIS/OBJECTIVES

To test the effect of prednisolone used in the first weeks of an EDT in order to reduce the total time period for diagnosis. The goal was to perform food challenges earlier than after the traditionally recommended eight weeks.

ANIMALS

Fifty-three dogs with AD were included in the study.

METHODS AND MATERIALS

All dogs were fed a commercially available extensively hydrolyzed protein-based commercial pet food and treated with prednisolone for at least two weeks to control pruritus and inflammation. Dogs were challenged two weeks after prednisolone finished, provided that no flare had occurred. Dogs with relapsing signs were fed the hydrolyzate for at least eight weeks with or without further prednisolone treatment.

RESULTS

Ten of 53 dogs (19%) had no relapse after two weeks off prednisolone: they were subsequently challenged with their regular food, had a relapse of signs and were diagnosed with a food-induced AD within four to six weeks of starting the EDT. In the other dogs, signs remained uncontrolled without prednisolone or relapsed rapidly after its discontinuation: they were considered nonfood-allergic after an eight week EDT.

CONCLUSION AND CLINICAL IMPORTANCE

This study demonstrates that a shorter EDT is possible if the allergic pruritus and inflammation are initially controlled with a short course of glucocorticoids. This shortened trial is likely to improve owner adherence and facilitate the diagnosis of food allergy.