Grado de mastitis bovina según la etapa de lactancia mediante el conteo de células somáticas totales y diferenciales y su relación con parámetros productivos

Abstract

Bovine mastitis constitutes the main pathology in dairy production systems, generating significant economic losses due to decreased production and deterioration of milk quality. This research aimed to: characterize total somatic cell count (SCC) and differential somatic cell count (DSCC) in dairy cows according to lactation stage, compare the degree of bovine mastitis through udder health group classification, and analyze the relationship between mastitis degree, lactation stage, and productive parameters to identify associated risk factors. The study was conducted at Hacienda Kuripamba, Cayambe, Pichincha, Ecuador (2,830 m.a.s.l.), working with 90 dairy cows (Holstein, Jersey, and F1) from which 540 samples were obtained over six consecutive weeks. SCC and DSCC analysis was performed using flow cytometry with FOSSOMATIC 7DC equipment. Factors such as lactation stage, breed, number of parities, milk production, and days in milk were evaluated, using a completely randomized design with factorial arrangement. Results revealed that early lactation presented the highest values of SCC (116.19 ×10³ cells/mL) and DSCC (40.89%), with significant differences between stages (p=0.021). Quadrant classification determined that 77.8% of cows were healthy, 17.8% sensitive, and 4.4% with subclinical mastitis. A significant correlation was identified between SCC and number of lactations (r=0.254; p=0.016), evidencing that multiparous cows present greater susceptibility. Holstein concentrated 100% of subclinical mastitis cases (p=0.025). These findings demonstrate the importance of systematic SCC-DSCC monitoring as an early diagnostic tool, considering lactation stage, parity, and breed as determining factors in udder health.