Contamination of cow milk by heavy metals in Serbia

Background: Dairy cows are exposed to numerous environmental hazards, such as heavy metals. Milk and dairy productscould be harmful to humans when maximum tolerable amounts of heavy metals are exceeded. Analysis of heavy metals inmilk is important because milk is a source of essential nutrients and is an indicator of environmental contamination. Someheavy metals are essential to maintain proper metabolic activity in living organisms, but at exceeded levels they could betoxic to living organisms. The main objective of the present study was to determine the residue levels of ten heavy metals(As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn) in cow milk in Serbia.Materials, Methods & Results: The experiment was conducted at three farms at Vojvodina district, Serbia. Cows fromall three farms were on pasture during spring and summer time. Randomly 50 cows from each farm were taken for thisexperiment. The cows have similar body condition score they were in their third or fourth lactation and gave approximatelythe same amount of milk in the previous lactation. Total 150 milk samples were collected from cows during the morningmilking, in the period between April to May in 2016. All 150 milk samples were transported to laboratory as soon as possible and analyzed for the heavy metals. Heavy metals were analyzed by Inductance coupled plasma - optical emissionspectrometry. Data are presented as mean values ± sd. Statistical analysis was done by one way repeated measures analysisof variance (ANOVA). The level of significance was set at P < 0.05. The highest average concentration in cow milk wasdetermined for Iron (283.9 mg/kg), then for Zinc (60.21 mg/kg) and Copper (4.404 mg/kg), while the lowest concentrationwas for Cobalt and Lead (less than 0.005 mg/kg).Discussion: Bioaccumulation is one of the biggest problems with heavy metals. Heavy metals residues in milk can be verydangerous for the calves and humans as well...

Contamination of cow milk by heavy metals in Serbia

Background: Dairy cows are exposed to numerous environmental hazards, such as heavy metals. Milk and dairy productscould be harmful to humans when maximum tolerable amounts of heavy metals are exceeded. Analysis of heavy metals inmilk is important because milk is a source of essential nutrients and is an indicator of environmental contamination. Someheavy metals are essential to maintain proper metabolic activity in living organisms, but at exceeded levels they could betoxic to living organisms. The main objective of the present study was to determine the residue levels of ten heavy metals(As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn) in cow milk in Serbia.Materials, Methods & Results: The experiment was conducted at three farms at Vojvodina district, Serbia. Cows fromall three farms were on pasture during spring and summer time. Randomly 50 cows from each farm were taken for thisexperiment. The cows have similar body condition score they were in their third or fourth lactation and gave approximatelythe same amount of milk in the previous lactation. Total 150 milk samples were collected from cows during the morningmilking, in the period between April to May in 2016. All 150 milk samples were transported to laboratory as soon as possible and analyzed for the heavy metals. Heavy metals were analyzed by Inductance coupled plasma - optical emissionspectrometry. Data are presented as mean values ± sd. Statistical analysis was done by one way repeated measures analysisof variance (ANOVA). The level of significance was set at P < 0.05. The highest average concentration in cow milk wasdetermined for Iron (283.9 mg/kg), then for Zinc (60.21 mg/kg) and Copper (4.404 mg/kg), while the lowest concentrationwas for Cobalt and Lead (less than 0.005 mg/kg).Discussion: Bioaccumulation is one of the biggest problems with heavy metals. Heavy metals residues in milk can be verydangerous for the calves and humans as well...(AU)

Lactoferrin and immunoglobulin G concentration in bovine milk from cows with subclinical mastitis during the late lactation period

Background: Lactoferrin and immunoglobulin G in milk have an important role in udder resistance to infection in the involution period. Both proteins express antimicrobial activity- lactoferrin by the binding and sequestration of iron ion; and immunoglobulin G by complement activation, bacterial opsonization and agglutination. Many factors affect lactoferrin and immunoglobulin G concentrations in bovine milk, such as the stage of lactation, milk production, and intramammary infections. The aim of this study was to determine concentrations of lactoferrin and immunoglobulin G in milk from healthy cows and subclinical mastitic cows during the late lactation period, and to evaluate the relationship between them. Materials, Methods & Results: A total of 150 quarter milk samples from 41 cows (Holstein-Friesian breed) in late lactation period were reviewed in this study. Milk samples were collected during morning milking, using aseptic techniques in sterile test tubes. From each sample, 0.1 mL of milk was plated on Columbia blood agar base with 5% defibrinated ovine blood, MacConkey agar and Sabouraud dextrose agar and incubated for 24 h - 48 h (bacteria) and 5 days (yeasts, mould) at 37oC. Milk samples for detection lactoferrin and immunoglobulin G concentration were skimmed at 1,400 g for 45 min and stored at -20C until analysis. Lactoferrin concentration in bovine milk was [...](AU)

Lactoferrin and immunoglobulin G concentration in bovine milk from cows with subclinical mastitis during the late lactation period

Background: Lactoferrin and immunoglobulin G in milk have an important role in udder resistance to infection in the involution period. Both proteins express antimicrobial activity- lactoferrin by the binding and sequestration of iron ion; and immunoglobulin G by complement activation, bacterial opsonization and agglutination. Many factors affect lactoferrin and immunoglobulin G concentrations in bovine milk, such as the stage of lactation, milk production, and intramammary infections. The aim of this study was to determine concentrations of lactoferrin and immunoglobulin G in milk from healthy cows and subclinical mastitic cows during the late lactation period, and to evaluate the relationship between them. Materials, Methods & Results: A total of 150 quarter milk samples from 41 cows (Holstein-Friesian breed) in late lactation period were reviewed in this study. Milk samples were collected during morning milking, using aseptic techniques in sterile test tubes. From each sample, 0.1 mL of milk was plated on Columbia blood agar base with 5% defibrinated ovine blood, MacConkey agar and Sabouraud dextrose agar and incubated for 24 h - 48 h (bacteria) and 5 days (yeasts, mould) at 37oC. Milk samples for detection lactoferrin and immunoglobulin G concentration were skimmed at 1,400 g for 45 min and stored at -20C until analysis. Lactoferrin concentration in bovine milk was [...]