The Influence of Selected Factors on the Nutritional Value of the Milk of Cold-Blooded Mares: The Example of the Sokólski Breed.
Authors: Barłowska Joanna, Polak Grażyna, Janczarek Iwona, Tkaczyk Ewelina
Journal: Animals : an open access journal from MDPI
Summary
# Editorial Summary Researchers at the University of Life Sciences in Lublin examined how management and biological factors influence the composition and nutritional quality of milk from nine Sokólski cold-blooded mares across 79 samples, analysing macronutrient content, whey protein fractions (α-lactalbumin, β-lactoglobulin, serum albumin, immunoglobulins, lactoferrin, and lysozyme), and fatty acid profiles. Stalled mares produced milk richer in dry matter, fat, lactose and ash with superior immunological markers (higher β-lactoglobulin, α-lactalbumin, immunoglobulins and lactoferrin), whereas pasture-access mares yielded higher absolute protein levels and elevated lysozyme and serum albumin fractions—suggesting a trade-off between caloric density and immune function based on housing. Advancing lactation number significantly shaped milk quality: mares in their fourth to sixth lactations produced the most protein and fat whilst minimising lactose, alongside markedly improved fatty acid profiles with lower saturated fatty acids and higher mono- and polyunsaturated fatty acids; notably, α-lactalbumin peaked early (lactation 1) whilst lactoferrin was highest mid-lactation (lactations 2-3). Mares nursing female foals consistently produced nutritionally superior milk across most parameters, including enhanced lysozyme content and fatty acid balance. These findings have important implications for breeding programmes, foal nutrition strategies, and management decisions—particularly the recognition that lactation parity and offspring sex influence milk composition independently of breed genetics, suggesting targeted nutrition protocols could optimise foal growth trajectories at different life stages.
Read the full abstract on PubMed
Practical Takeaways
- •Pasture access affects milk composition differently by component—while it increases protein and certain protective proteins, confined mares produce milk with higher energy density and better fatty acid balance, suggesting different nutritional strategies may benefit different foals
- •Lactation stage significantly influences milk quality, with older lactations (4-6) providing superior nutritional profiles, particularly for fatty acid composition important for foal growth and development
- •Sex of offspring influences dam milk composition, with mares nursing fillies producing nutrient-denser milk, suggesting potential biological programming or differential nutritional allocation strategies
Key Findings
- •Mares without pasture access produced milk with higher dry matter, fat, lactose, and ash content, plus higher β-lactoglobulin, α-lactalbumin, immunoglobulins, and lactoferrin percentages
- •Mares on pasture produced milk with higher total protein content and higher serum albumin and lysozyme percentages
- •Milk from mares in lactations 4-6 showed highest fat and protein concentrations with lowest lactose, and best fatty acid profiles with lowest saturated fatty acids and highest unsaturated fatty acids
- •Milk from mares nursing female offspring had higher dry matter, fat, and protein concentrations with better fatty acid profiles and higher lysozyme content