Nutritional quality and the adequacy of donkey milk in the diet of allergic children

Recent investigations have shown that donkey milk (DM) can be considered hypoallergenic in cases of cow milk protein allergies (CMA) and that it has a high acceptance rate by the children. Since DM could represent a natural alternative for allergic babies, the aim of this study was to evaluate the nutritional quality and adequacy of DM in the feeding of children with IgE-mediate cow's milk protein allergy and Food Protein Induced Enterocolitis Syndrome. DM was supplied by a donkey farm from central Italy conforming with EU regulation 853/2004. Eighteen bulk milk samples were taken monthly and analysed for gross and mineral composition, fatty acid profile, and vitamin D content. After an allergological work-up, nutritional plans including DM were prepared for 22 allergic children referring to the Allergy Unit of Meyer Children Hospital of Florence (Italy). Fat and vitamin D supplementations were supplied according to the age of the children. The nutritional state of the babies was evaluated considering weight and length/stature at the beginning and the end of the study. The gains were calculated in terms of Z-score (Z=x-X/s.d.). Mean and s.d. of milk chemical composition were calculated, and Z-score values were analysed by t-test. Similarly, to human milk, lactose was 7.05±0.150%, and proteins were 1.59±0.137%, with caseins representing about 50% of the total protein. Fat and ash were 0.31±0.053% and 0.37±0.022%, respectively. Like human milk, calcium and potassium were the main minerals and were 633.31±137.440 and 653.32±69.21 mg/L respectively, while zinc content was 3.16±1.500 mg/L. Unsaturated fatty acids were 48 g/100g of fat (Table 1). In addition, DM was richer in n3 linolenic acid (7.52±2.49 g/100g of fat) and vitamin D (1.97±0.454 μg/100ml), than both human and cow milk. The infants increased in weight and length/stature similarly to the reference population. In conclusion, DM was found to be nutritionally adequate using supplementations according to the age of the children. Further investigations in the field of farming techniques and genetic improvement of dairy donkeys are still ongoing. Table 1. Classes of fatty acids and unsaturated fatty acid profile of donkey’s milk (g/100g of fat) Fatty acid Mean s.d. Fatty acid Mean s.d. C14:1 0.40 0.114 CLA c9. t11 0.07 0.045 C15:1 0.17 0.098 C20:1 0.13 0.090 C16:1 3.86 0.840 C20:2 0.13 0.066 C17:1 0.40 0.098 C20:3n3 0.21 0.060 C18:1 t-9 0.04 0.004 C20:3 n6 0.07 0.061 C18:1 t-11 0.05 0.035 C22:1 0.25 0.052 C18:1 c-9 21.58 2.904 C20:4n6 0.07 0.035 C18:1 c-11 1.08 0.273 C22:2 0.10 0.087 C18:2 t-9.12 0.08 0.066 C20:5 0.07 0.060 C18:2 c-9.12 11.18 1.904 C24:1 0.06 0.070 C18:3n3 7.52 2.494 C22:5 0.10 0.084 C18:3 n6 0.13 0.078 C22:6 0.05 0.041 SCFA (≤C10) 11.97 2.131 SFA 52.17 3.987 MCFA(≥C11≤C17) 42.93 4.155 MUFA 28.05 3.487 LCFA(≥C18) 45.10 3.731 PUFA 19.79 2.433 n3/n6 0.72 0.274 UFA/SFA 0.93 0.141 SCFA: short-chain fatty acids (from C4:0 to C10:0); MCFA (from C11:0 to C17:0): medium-chain fatty acids; LCFA (from C18:0 to C24:0): long-chain fatty acids; SFA: saturated fatty acids; MUFA: monounsaturated fatty acids; PUFA: polyunsaturated fatty acids; UFA=unsaturated fatty acids; s.d.=standard deviation