Effects of clinoptilolite on heavy metal levels in milk, proinflammatory cytokine responses (IL-1β and IL-6) and oxidative stress in dairy cows.

The effects of clinoptilolite on milk copper (Cu), lead (Pb), zinc (Zn), cadmium (Cd) and iron (Fe) concentrations, proinflammatory cytokine responses, oxidative stress status, whole blood cell counts and liver and kidney functions were investigated in dairy cows exhibiting no signs of any kind of toxicity. Clinoptilolite was added to the feed at a dose of 200 mg kg-1 body weight in the clinoptilolite-treated group (n = 14), but was not added to the feed in the control group (n = 7). In the milk samples (n = 21) collected before the experiment, the Cu, Pb, Zn, Cd and Fe values were 0.021 ± 0.020, 0.104 ± 0.01, 3.42 ± 0.32, <0.000, 0.56 ± 0.34 ppm, respectively. At the end of the experiment (30th day), among the elements measured in milk samples collected from the clinoptilolite-treated group, only the Pb value (0.076 ± 0.01) was lower than the 0-day value of the clinoptilolite-treated group (0.104 ± 0.01) and the 30th-day value of the control group (0.105 ± 0.01) was found to be statistically lower. Changes determined at the end of clinoptilolite application in serum superoxide dismutase (SOD), malondialdehyde (MDA), albumin, glucose, urea and urine creatinine/urine total protein (uCr/uTP) values, which were interpreted as the effect of lead exposure before the trial, were evaluated as the positive effect of clinoptilolite. It was concluded that the addition of clinoptilolite to the feed in dairy cows caused a significant decrease in the amount of Pb in milk, and positive changes in the parameters related to oxidative stress in serum and in parameters related to renal function.