Effects of pea with barley and less-processed maize on glycaemic control in diabetic dogs

Abstract

The source of starch may interfere with glycaemic control in dogs, but few studies have evaluated these aspects in diabetic dogs. This study compared the effects of two isonutrient diets with different starch sources, peas and barley (PB) v. maize (Mi), on diabetic dogs. The Mi diet was processed in order to generate a lower starch gelatinisation index. In all, fifteen adult diabetic dogs without other conditions were included. The animals were fed two dry extruded rations with moderate levels of fat and starch and high levels of protein and fibre using a random, double-blind cross-over design. Glycaemic curves over 48 h were developed via continuous glucose monitoring after 60 d on each diet and with the same neutral protamine Hagedorn (NPH) insulin dosage. The following were compared: fasting, mean, maximum and minimum blood glucose, maximum and minimum glycaemia difference, glycaemic increment, area under the glycaemic curve, area under the glycaemic increment curve and serum fructosamine concentration. Paired t tests or Wilcoxon signed-rank tests were used to compare the amount of food and nutrients ingested and the dietary effects on glycaemic variables between the diets. Dogs fed the PB diet presented a lower average mean interstitial glucose (P=0·01), longer mean hypoglycaemic time (P<0·01), shorter mean hyperglycaemic time (P<0·01) and smaller difference between maximum and minimum blood glucose levels (P=0·03). Thus, the processing applied to the Mi diet was not sufficient to achieve the same effects of PB on glycaemic control in diabetic dogs.

Starch sources influence lipidaemia of diabetic dogs

“…A recent metabolomic study with obese humans found differential regulation of certain amino acids and phospholipids depending on the diet's glycemic index [46], which could contribute to explain the lipid-lowering effects attributed to low-glycemic index diet on diabetic or hyperlipidemic humans reported previously [47,48]. It was not measured in our study, but we have already shown that a pea and barley-based diet generate lower glycemic variables in diabetic dogs when compared to a maizebased diet [29]. Additionally, Adolphe et al [49] pointed that pea has lower glycemic index compared to others starch sources as rice in dogs.…”

“…Although 12 animals represent a small sample size, based on previous research this study included the similar number of diabetic dogs evaluated for dietary modifications under a crossover design as other studies [21][22][23]29]. All the animals were spontaneous diabetic dogs and were included after a rigorous selection, considering even the owners commitment to following the protocol.…”

“…The animals used in this research were selected from the routine practice of the veterinary hospital of the School of Veterinary Medicine and Animal Science of the University of São Paulo as our previous study [29]. In which the medical records of 368 diabetic dogs were analyzed and 18 animals were selected according to the following exclusion criteria (intact female dogs; dogs younger than 1 year old; diagnosis of concomitant diseases; body condition score (BCS) lower than 4 or higher than 6 on a scale [57] of 1 to 9).…”

“…The minimum number of animals, to achieve 80% of power calculation, was performed by glycemic values from Teshima et al [30]. This sample size was calculated using statistical program Action® to previous research project [29] and resulted in 10 diabetic dogs.…”

“…Starch source affect significantly the digestibility of the diet [28]; and interferes with the postprandial glycemic curves in diabetic dogs [29,30]. Previously, our group showed that pea and barley mix as exclusive dietetic starch minimize postprandial glycemia in diabetic dogs compared to maize [29]. But studies focusing on lipid profile of dogs with endocrinopathies feeding different starch sources were not found.…”