Influence ofinfection on milk production and quality of Holstein dairy cows.

Abstract

We wished to determine ifinfection can negatively impact milk quality and production in Holstein dairy cows. For this Research Communication, milk samples (271) from Holstein cows from 3 herds were screened forby real-time PCR. Positive (= 21) and negative animals (= 21) were matched by herd, age, lactations and days in milk (DIM). Pairs were evaluated in 7 stages of lactation: D1-50, D51-100, D101-150, D151-200, D201-250, D251-300, and D ≥ 301. A mixed model was used to assess the effect of groups (×), time (lactation) and groups × time interaction. Cows positive forhad lower average milk production per day and high somatic cells count (SCC).