The effect of the state of “loaded metabolism” assesses the level of lead in the productivity of dairy cows

Abstract

Abstract Annotation. The study was performed on clinically healthy cows of Holstein breed during the period of milking in the CJSC "Gatchina" of the Leningrad region (Russia). Animals (n = 60) were divided into groups depending on the severity of "loaded metabolism" estimated by lead concentration in wool: up to the 25th centile, within the 25th to 75th centile, above the 75th centile. The concentration of lead in wool was determined by atomic emission and mass spectrometry (AES-ICP and MS-ICP). It was found that about the increase in lead content from the minimum to the maximum in centile intervals from 25-75 to> 75, the level of malondialdehyde (Total-MDA) in the blood increased, which was recorded against the background of a decrease in milk productivity. A significant negative correlation was observed between the concentration of lead in wool and the yield of milk fat, protein, dry matter, and corrected for 1% milk fat.