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The aims of this study were to i) characterize sheep milk for non-enzymatic antioxidant activity via 2 different assays, namely the ferric reducing antioxidant power (FRAP) and the 2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH), and ii) investigate the effect of milk composition and animal-related parameters on these 2 assays by using Generalized Additive Mixed Model (GAMM) approach. A total of 740 ewes belonging to Massese and Comisana breeds were sampled once during the morning milking across 11 sampling sessions. All milk samples were analyzed for fat, protein, casein, and lactose, somatic cell score (SCS) and minerals (Ca, Mg, Na and Cl). The FRAP and DPPH assays were tested to measure the non-enzymatic antioxidant activity of milk, expressed as μM eq. ascorbic acid/mL of milk and % of inhibition, respectively. The GAMM model included the effect of parity and breed as parametric terms, and the effect of days in milk (DIM), milk yield and the interactions protein × fat, casein × SCS, Ca × Mg and Na × Cl as smooth terms. The sampling day was included in the model as random effect. Results revealed that the non-enzymatic antioxidant capacity of sheep milk, expressed as FRAP, was affected by DIM, potentially because of changes in milk composition over time. Conversely, parity and breed of ewes affected DPPH, suggesting that age- and breed-specific factors are related to specific components in milk acting as hydrogen donors. Milk fat and high casein percentages were found to significantly affect FRAP, while protein content was crucial for high DPPH levels. Additionally, Ca and Mg emerged as important non-enzymatic antioxidants for both FRAP and DPPH, highlighting their important role in antioxidant activity of sheep milk. On the other side, combinations of Na and Cl were particularly influential for FRAP, revealing the complex relationship between these minerals and non-enzymatic antioxidant activity of milk. These findings offer valuable insights into the factors affecting the antioxidative properties of sheep milk, highlighting the need for further exploration of other non-enzymatic antioxidants and their contribution to the total antioxidant activity., (The Authors. Published by Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).)

The objective of this study was to assess the effect of using or not using the genotypes of the parents of a cow for imputing SNPs on the estimation of genomic inbreeding coefficients of cows. Imputation (i.e., genotyped plus imputed) genotypes from 68,127 Italian Holstein dairy cows registered in the Italian National Association of Holstein, Brown, and Jersey Breeders were analyzed. Cows were genotyped with the high-density (HD) Illumina Infinium BovineHD BeadChip and GeneSeek Genomic Profiler HD-150K, and the medium-density (MD) GeneSeek Genomic Profiler 3, GeneSeek Genomic Profiler 4, GeneSeek MD, and the Labogena MD. To assess differences among estimators, genomic inbreeding coefficients were estimated with 4 PLINK v1.9 estimators (F, F hat1 ,F hat2 , andF hat3 ), 2 genomic relationship matrix- (grm) based estimators (F grm and F grm2 , with the latter including also pedigree information), and one estimator of runs of homozygosity (ROH; F ROH ). Assuming that the correct genomic inbreeding coefficients should be those estimated from genotyped SNPs, a comparison of the genomic inbreeding coefficients estimated either with the genotyped SNPs or the SNPs after imputation was made. Information on the presence or absence of genotypic information from sire, dam, and maternal grandsire during the imputation was investigated. Genomic inbreeding coefficients estimated with genotyped SNPs or SNPs after imputation were consistent for F, F hat3 , F grm2 , and F ROH , when at least one of the parents was genotyped. Biased (mainly higher) genomic inbreeding coefficients of imputation SNPs were observed in cows that were genotyped with MD SNP panels whose SNPs were poorly represented in the selected imputation SNP dataset and also did not have their parents genotyped, when compared with what would be expected based on actual genotype data. For cows genotyped with MD the estimators F hat1 , F hat2 , and F grm provided higher genomic inbreeding coefficients of imputation SNPs even with both parents and the maternal grandsire genotyped. Overall, F ROH was the most robust estimator, followed by F and F hat3 . Our findings suggest that SNPs selection, parental genotyping and estimator should be considered for designing imputation strategies in dairy cattle for estimating genomic inbreeding with imputation SNPs. For computing genomic inbreeding coefficients, it is recommendable to have at least one parent genotyped and use an ROH-based estimator., (© 2024, The Authors. Published by Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).)

The present study aimed to investigate the influence of ripening on the physicochemical, microbiological aspects, and fatty acid profile of Artisanal Coalho Cheeses and to detect if there are peptides with bioactive potential in their composition. Artisanal Coalho Cheese samples were kindly provided by a dairy farm located in Brazil in the Rio Grande do Norte state. A completely randomized design was adopted, with four maturation periods (0, 30, 45, and 60 days). Physicochemical traits (pH, total solids, moisture, non-fat solids, fat in total solids, protein, ash, fatty acid profile) and microbiological characterization (Salmonella sp, Listeria monocytogenes, total and thermotolerant coliforms, Staphylococcus aureus) were analyzed on cheese samples. Additionally, assays were performed for antioxidant and antihypertensive bioactivity through ACE and antimicrobial inhibition of the peptides extracted from the samples. There was a linear increase in total solids and ash content and a decrease in moisture content with increasing maturation time. The matured cheese samples had a lower pH than fresh Artisanal Coalho Cheese. Twenty-seven fatty acids were identified in the cheeses: 15 saturated, 07 monounsaturated, and 05 polyunsaturated, with a linear reduction of essential fatty acids (n6 and n3) during maturation. The microbiological quality of the cheeses was satisfactory, with an absence of undesirable bacteria in 92% of the cheese samples. Water-soluble peptide fractions from all periods tested showed antioxidant and antihypertensive potential with ACE control, and the maturation process potentiated these capacities, with a decline in these activities observed at 60 days. The antimicrobial activity against Gram-positive and Gram-negative bacteria increased with maturation, reaching better results until 60 days. The maturation process on wooden planks in the periods of 30, 45, and 60 days allows the production of Artisanal Coalho Cheese of an innovative character, safe to consumers from the microbiological point of view, with differentiated physicochemical and functional characteristics and good quality of lipid fraction compared to fresh cheese, enabling the addition of value to the dairy chain., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Bezerra et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)