Enhancement of Dairy Cow Milk Quality with Probiotic and Inorganic Selenium Supplementation.

Selenium (Se) is an essential micronutrient crucial in various metabolic processes. Dairy production is continually expanding and can supplement the population of regions with low Se. Adding live yeast concentrate (LYC) to cows' diets can influence milk production, composition, and quality by modulating ruminal microbiota, resulting in increased milk yield and improved nutritional content. This study aimed to assess the enrichment of milk with selenite LYC for a subsequent increase in quality and production in supplemented lactating cows. Twenty-six cows were separated into three groups supplemented with different concentrations of Se for 15 days and different concentrations of LYC (Saccharomyces cerevisiae at 108 CFU g−1). The animals were divided into the following groups with the proposed treatments: Treatment 1 (T1) Control Group with just dry matter intake (DMI); Treatment 2 (T2) DMI + 0.3 mg kg−1 DMI of inorganic selenium + live yeast concentrate (LYC); Treatment 3 (T3) DMI + 0.6 mg kg−1 DMI of inorganic selenium + LYC. The milk was evaluated using physical–chemical, microbiologic, and toxicologic parameters according to Brazilian legislation. The addition of Se and yeast did not alter milk production; however, the application did lead to an increase in milk fat concentration compared with the control group, and no significant variations were observed in other physical–chemical parameters. Regarding the microbiological and toxicological analyses, all the samples presented satisfactory hygienic and sanitary conditions. The Somatic Cells Count from all treatments remained below 500,000 somatic cells mL−1, representing a positive effect of Se. The milk Se content was expected in residual form with the organic selenium being the more bioavailable form throughout the processing chain. The supplementation yielded results similar to those in the literature, highlighting the potential for customized technology and processes in dairy farming in ways that improve production, quality, and sanitation. [ABSTRACT FROM AUTHOR]