Production of hydrogen peroxide by a small molecular mass compound in milk from Holstein cows with high and low milk somatic cell count

Abstract

Mastitis is the most frequent and prevalent production disease in dairy herds in developed countries. Based on a milk somatic cell count (SCC) of either >300,000 or <200,000 cells/ml in this study, we defined the quarter as either inflamed or uninflamed, respectively. The electrical conductivity (EC) of milk was used as an indicator of udder epithelial cell damage. We determined the amount of H2O2 produced by utilizing a small molecular weight compound in milk, and examined the characteristics of H2O2 production and EC in milk from inflamed and uninflamed quarters. In cows with milk of delivery grade (control population), H2O2 production and EC were 3.6+/-1.3 nmol/ml and 5.4+/-0.4 mS/cm (mean+/-sd), respectively. In 37 inflamed quarter milk samples, the production of H2O2 was 1.9+/-1.0 nmol/ml and was significantly smaller than that in the control population (P<0.01). Production of H2O2 was moderately but significantly correlated with EC (r<-0.71). In 20 cows with inflamed quarters, the production of H2O2 in milk from inflamed quarters was significantly smaller than that in milk from uninflamed quarters (P<0.01). In 18 out of 20 cows, milk from inflamed quarters showed the smallest H2O2 production among all tested quarters in each cow. We conclude that inflammation caused a decrease in H2O2 production in milk. In this study, we present parameters for evaluating the lactoperoxidase/H2O2/thiocyanate antibacterial defence system in bovine milk.

Inclusion of grape marc in dairy cattle rations alters the bovine milk proteome

“…Sulfhydryl oxidases are plentiful, and some potentially have a role in innate immunity geared toward offspring protection (Isaacs et al ., 1984), but ultimately this enzyme oxidizes free sulfhydryl groups by using oxygen as an electron acceptor with hydrogen peroxide being produced as a result. Hydrogen peroxide production in milk is reduced in other periods of higher blood and milk interactivity, including mammary inflammation caused by mastitis (Sakai et al ., 2008), and hence a decrease in sulfhydryl oxidase abundance is in line with our suggestion that the blood-milk barrier may be affected by feeding GPM.…”

Proteomics, Genomics, and Pathway Analyses ofEscherichia coliandStaphylococcus aureusInfected Milk Whey Reveal Molecular Pathways and Networks Involved in Mastitis

“…57 However, for the system to function, H 2 O 2 must be present. Sakai et al 58 recently showed that inflammation of the mammary gland caused a decrease in H 2 O 2 production in milk. Therefore, the presence of E. coli and S. aureus possibly inactivated the LPO/H 2 O 2 /thiocyanate system in infected milks and caused the down-regulation of LPO.…”