Changes in the Fatty Acid Composition of Milk of Lipizzaner Mares during the Lactation Period

Nutritional composition, fatty acids profile and immunoglobulin G concentrations of mare milk of the Chilean Corralero horse breed

The objective of the present study was to characterize the nutritional composition, fatty acid profile, and IgG concentration of the milk produced by Chilean Corralero horse (CCH) mares from breeding farms located in southern Chile. Forty-five milk samples were collected from three of the biggest breeding farms (coded as A, B and C) specialized in breeding and selection of CCH in Chile (15 mares sampled per farm). Farms differed in days in milk (DIM). A negative association between DIM and ash, milk protein, milk solids, saturated fatty acids (SFA), and gross energy (GE) was found, whereas DIM had a positive association with monounsaturated fatty acids (MUFA). Milk components like fat, lactose, and energy content varied independently of DIM, indicating other influencing factors such as farm-specific management practices. Offspring sex moderately affected GE content, with milk from mares bearing female offspring having higher GE. Macronutrient profiles of the CCH mares' milk were within the reported range for other horse breeds but tended to have lower fat and total solids. Compared to cow and human milk, horse milk is richer in lactose and lower in fat and protein. Immunoglobulin G concentration was only affected by the farm (B > A) which could be linked to dietary factors and pasture composition rather than maternal parity or other known factors. Overall, CCH mare milk has notable nutritional characteristics, with implications for both foal health and potential human consumption, posing less cardiac risk compared to cow's milk as indicated by lower atherogenic and thrombogenic indices.

Chemical composition, whey protein profile, and fatty acid profile of milk from Sokólski horses in relation to Polish Halfbred horses

The study was carried out on milk from cold-blooded Sokólski mares and warm-blooded Polish Halfbred mares. Milk samples were analysed for content of dry matter, protein, fat, lactose, and ash; density; energy value; percentage of α-lactalbumin (α-La), β-lactoglobulin (β-Lg), serum albumin (SA), immunoglobulin (Ig), lactoferrin (Lf) and lysozyme (Lz) in the total protein; and fatty acid profile. Milk from cold-blooded mares was found to be similar in protein and fat content to that of warm-blooded mares, but had higher content of dry matter, including lactose and ash. It also had significantly (P≤0.01) higher content of α-La, SA and Lz, and lower content of β-Lg, Ig and Lf in comparison to milk from warm-blooded mares. Milk from Sokólski horses had a significantly (P≤0.01) higher proportion of SFA, including C10:0, C12:0, C14:0, C16:0 (P≤0.01) and C18:0 (P≤0.05), while the milk of warm-blooded mares had a significantly (P≤0.01) higher proportion of MUFA, including C16:1n-9 and C18:n-9, and PUFA, including C18:2n-6 and C18:3n3. The share of n-6 and n-3 PUFA was significantly (P≤0.01) higher in milk from warm-blooded horses, but their ratio (n-6/n-3) was lower (more favourable) in milk from cold-blooded mares. In addition, milk from warm-blooded horses had a lower (P≤0.01) share of HSFA and a higher proportion of DFA compared to cold-blooded horses, as well as lower values for AI and TI. Despite these minor differences in comparison with warm-blooded mares (Polish Halfbred), milk from cold-blooded Sokólski mares was shown to be a food product of high nutritional value, which is one argument in favour of the use of this horse breed for dairy purposes.