Zinc effect on milk somatic cell count in dairy cows

Davidov, IvanaRadinović, MiodragErdeljan, MihajloJurakić, ŽeljkaKovačević, Zorana

Background: The cow’s requirement of zinc must be provided in the diet. The contents vary between different feedstuffs,and can be negatively influenced by factors like soil type, harvest, storage conditions. Also vary due to stage of lactation andhealth status of cow. Therefore, extra supplementation of zinc is sometimes warranted. Adequate zinc intake is particularlyimportant during the late dry period and the early stages of lactation in order to prevent diseases around parturition. Theaim of this study was to measure the concentrations of zinc in blood samples taken from dairy cows in different state oflactation and comparing with somatic cell count in cows milk.Materials, Methods & Results: A total of 45 Holstain cows were divided on days of milking into 3 groups of 15 cows (groupA, B and C). All cows were stabling with dry straw for bedding and with ad libitum access to potable water, and feed bytotal mixed ration. Blood samples were taken after the morning milking from the caudal vein by applying the principles ofasepsis and antisepsis. Blood samples were taken in vacutainer tubes with added anticoagulant K3E in quantities of 0.072mL. Milk samples were taken during morning milking. The whole milk samples were taken with milk meter for somaticcell count. When quarter milk samples were taken the teat ends were disinfected. After analyzing the results, blood meanzinc concentration was found to be lower in group B of cows. Group C had highest level of blood zinc concentration. Themean estimate blood zinc concentration in group A was 16.66 µmol/L, in group B was 8.26 µmol/L and in group C was17.82 µmol/L. Mean value of milk somatic cell count in group A was 298.67/mL, in group B was 451.33/mL and in groupC 492.67/mL...(AU)

1. dairy cow
2. somatic cell count
3. zinc