Evolution of colostrum characteristics in Murgese mares during the first 48 hours after foaling

The conservation and reintroduction of autochthonous livestock breeds has been increasingly recommended as an effective biodiversity conservation strategy. Over the centuries, they have contributed greatly to the shaping of most traditional Mediterranean landscapes, such as Murgese, the oldest surviving Italian horse breed. More recently, horse breeding has also gained importance for colostrum, with its characteristic properties and the possibilities of its use on a pharmaceutical, but also on a veterinary level. The colostrum of mares is characterised by a unique chemical composition: high percentage of dry matter (30%), a large amount of proteins (10% on average) and immunoglobulin. The foal should ingest the colostrum within the first hours after birth, as the absorption of macromolecules and immunoglobulins is highest in the first hours of its life. Therefore, the administration of colostrum to the foal is essential for its survival in all cases where the mother is unable to do so. In this study, the physicochemical composition and antioxidant activity of colostrum from Murgese mares were analyzed. Colostrum samples from 25 lactating mares were collected in the first 48 h after foaling in six different farms specialized in breeding Murgese horses in the Apulia region, Italy. The collections took place between February/2021 and April/2021. Colostrum samples were collected by manual milking after cleaning the udder and stored in previously sterilized plastic bottles (6–12–24–48 h after birth). The immunoglobulin content was measured with a refractometer at each sampling. The results showed that the values of most chemical parameters in colostrum were highest 6 h after foaling, especially fat, protein and brix content. In contrast, an increase in pH and lactose content was observed 48 h after birth. The colostrum in the first h was characterized by a high content of dry matter, protein and lysozyme and a high antioxidant activity. Its intake in the first 48 h of life guarantees the survival of the foal. In contrast, the foal's life is endangered if it does not absorb colostrum in the required quantity or quality, e.g. if it is abandoned by its mother or orphaned. For these reasons, the study was carried out in collaboration with the Territorial Biodiversity Office, which manages the Eastern Murge Biogenetic Nature Reserve, which has become a ‘public colostrum bank’ for national farms and all horse breeders.