Differing opinions of raw food diet research

Toxicosis with grapes or raisins causing acute kidney injury and neurological signs in dogs

Background

The ingestion of grapes or raisins has been reported to cause acute kidney injury (AKI) in dogs, with a clinical picture dominated by early gastrointestinal signs and rapidly developing uremia. Ataxia is mentioned in a few reports, but not further characterized.

Objectives

To evaluate the clinical, laboratory, and pathological features of dogs diagnosed with grape or raisin toxicosis (GRT) with emphasis on renal and neurological manifestations, compared to a control group of dogs with AKI from other causes.

Animals

Fifteen client‐owned dogs with GRT and 74 control dogs.

Methods

Retrospective study over 17 months.

Results

All dogs with GRT were presented with severe AKI (grade 4, n = 5; grade 5, n = 10). Eleven dogs (73%) had marked forebrain, cerebellar, or vestibular signs. These manifestations dominated the clinical picture in some dogs, but were not associated with the severity of azotemia or the presence of systemic hypertension. Eight dogs (53%) survived, and 5 dogs experienced a complete neurological recovery. Causes of death were unrelated to the neurological manifestations. Neuropathological examination of 4 dogs did not identify any structural central nervous system abnormality. Only 2 control dogs (3%) displayed neurological signs with seizures unrelated to the AKI; 42 control dogs (57%) survived.

Conclusions and Clinical Importance

Severe forebrain, cerebellar, or vestibular signs may be an important feature of GRT and dominate the early clinical picture. The described features suggest a reversible functional brain injury specific to GRT and unrelated to uremia.

The effect of a raw vs dry diet on serum biochemical, hematologic, blood iron, B12 , and folate levels in Staffordshire Bull Terriers

Background

To date, very few studies have compared the effects of different types of feeding practices on canine physiology, such as feeding exclusively dry, raw, or homemade foods.

Objectives

We aimed to report the changes in hematologic, serum biochemical, plasma folate, B₁₂, and whole blood iron levels in dogs fed two different diets.

Methods

A pilot study was developed to compare the effects of a heat‐processed high carbohydrate (HPHC) and nonprocessed high‐fat (NPHF) diet. A total of 33 client‐owned Staffordshire Bull Terriers were used; 18 had canine atopic dermatitis, seven were healthy, and eight were grouped as “borderline” dogs since they did not fulfill at least six of Favrot's criteria. The comparisons were made between the diet groups at the end visit of the diet intervention, as well as within the diet groups during the study.

Results

Significant differences between and within the diet groups were observed, although the majority of outcomes remained within the RIs. The median time of diet intervention was 140 days. Red blood cell counts, mean cell hemoglobin concentrations, and platelet counts were significantly higher, and mean cell hemoglobin, mean cell volume, alkaline phosphatase, inorganic phosphorus, and cholesterol were significantly lower in the dogs fed the NPHF diet compared with those fed the HPHC diet after the diet trial was completed. In addition, folate, B₁₂, and iron decreased significantly in the NPHF diet group.

Conclusions

This pilot study indicated that diet had an impact on blood values, although most remained within RIs, pointing out the need for further studies.

Household Food Items Toxic to Dogs and Cats

Several foods that are perfectly suitable for human consumption can be toxic to dogs and cats. Food-associated poisoning cases involving the accidental ingestion of chocolate and chocolate-based products, Allium spp. (onion, garlic, leek, and chives), macadamia nuts, Vitis vinifera fruits (grapes, raisins, sultanas, and currants), products sweetened with xylitol, alcoholic beverages, and unbaked bread dough have been reported worldwide in the last decade. The poisoning episodes are generally due to lack of public knowledge of the serious health threat to dogs and cats that can be posed by these products. The present review aims to outline the current knowledge of common food items frequently involved in the poisoning of small animals, particularly dogs, and provides an overview of poisoning episodes reported in the literature.

Canine renal pathology associated with grape or raisin ingestion: 10 cases

Ten dogs suffered acute renal failure after ingesting > or = 3 g/kg (dry matter) of grapes or raisins. All dogs had degeneration or necrosis (or both) of proximal renal tubules with basement membranes remaining intact, and epithelial regeneration was observed in 5 out of 10 cases. Mineralized tubular debris or granular to proteinaceous casts (or both) were present in all cases. A golden-brown, globular, intracellular pigment of varying amounts and sizes was observed in 6 out of 10 cases with variable reaction with Prussian blue. Multifocal fibrinous arteritis of the large colon was seen in 2 out of 5 cases with globulin insudation of vessel wall demonstrated by immunohistochemical staining for immunoglobulin (Ig)G and IgM. Mineral analysis on frozen renal tissue from 2 out of 2 cases revealed mildly elevated Ca:P ratio in both. Clinically significant observations were preservation of the integrity of basement membranes after grape-induced tubular injury and presence of early epithelial regeneration. Thus, recovery may be possible if anuria is aggressively managed. With respect to potential pathophysiologic mechanisms, further research into the roles of calcium homeostasis, vascular reactivity, and the significance of the golden-brown pigment is indicated.