Changes of heavy metal concentrations in goats milk during lactation stage in organic breeding

J. Novoselec, S. Cavar, Z. Antunovic, Z. Klir, B. Mioc, T. Klapec

Abstract: The investigations were carried out with 10 French Alpine goats. Investigation was done during winter-feeding season in organic breeding. All animals were in the fourth lactation, average age of four years, healthy and in good condition. They were fed with cereal mixture (oat, corn and barley) 1000 g/day and meadow hay (ad libitum). Milk samplings were carried out on 30th, 60th, 90th and 120th lactation day. Electrothermal technique was used to determine Cd and Pb concentrations whereas Hg concentration was determined with a hydride technique. There was no significant difference (P>0.05) between determined Cd, Pb and Hg concentrations with regard to the lactation period in goat milk. However, it should be stressed that Cd, Pb and Hg concentrations decreased in goat milk along with the increase of lactation (Cd: from 0.71 until 0.56; Pb: from 8.67 until 7.41; Hg: from 0.012 until 0.010 μg/kg DM). Concentration of heavy metals in goat milk showed connection with fodder samples. The presence of heavy metals in goat milk in organic breeding appeared to be in a very low concentration in these investigations and did not present any risk to human health.

Keywords: goat; heavy metals; lactation stage; milk; organic breeding

Date published: 2019-06-14