Effects of isoquinoline alkaloids from Macleaya cordata on physiological,immunological and inflammatory parameters in healthy beagles

The aim of the study was to investigate nutritional, physiological and immunological effects of a plant‐derived blend of isoquinoline alkaloids (Sangrovit® Extra) in healthy dogs. Two groups of healthy, adult beagles (N = 10) were tested in a cross‐over experiment, lasting two consecutive three‐week periods. The experimental group received 1.2 g additive/kg feed, according to the recommendation of 10–20 mg/kg live weight per day. The control group received the same feed without additive. Complete blood count, immunological parameters and amino acid concentrations in serum were assessed. Faeces were analysed for short‐chain fatty acids, lactate and ammonium; moreover, their quantity and consistency were determined. Neither feed intake, total apparent nutrient digestibility (crude protein and fat, organic matter, sodium, potassium) were affected by intake of the product. Lymphocyte and monocyte counts were slightly increased in both groups. Elevation was not treatment dependant. IgA, IgG, haptoglobin in serum and flow cytometric phenotyping of peripheral lymphocytes were not affected by alkaloids supplementation. Numerically greater methionine concentrations in blood serum occurred in the experimental group (p = 0.182). Quantity and consistency of faeces and ammonium concentration in faeces were not affected by the additive. Faecal concentrations of short‐chain organic acids differed between groups (acetic acid, % of total SCFA: control group 52.3 ± 5.2 vs. experimental group 57.1 ± 4.5, p = 0.042), lactate concentrations (d ‐, l ‐ and total) did not. Due to the shift of SCFA proportions in faeces, an effect of isoquinoline alkaloids (IQs) on the metabolic activity of intestinal microbiota is probable. In conclusion, the addition of IQs in the given dose was well tolerated and did not have adverse effects in healthy dogs.