Selenium Deficiency
(NY) Selenium deficiency continues to be diagnosed in cattle in NY, as exemplified in the following 3 recent cases. The first (Lewis County) was a submission of tissues from a 3-day-old dead Holstein heifer calf with apparent septicemia and Cryptosporidium colonization described on histopathology examination of fixed tissue. Her liver selenium was 0.66 ppm with the normal range for her age 1.5-6 ppm, on a dry matter basis. The second submission (Herkimer County) included samples from a 5-yr-old cow and a 5-mo-old calf, both with unexplained weight loss and recumbency. In addition to mild parasitism diagnosed in both, and Johne’s disease confirmed by fecal PCR in the cow, both were deficient in whole blood selenium, with the calf's selenium level being below the limit of detection of the assay. A third submission (Orleans County) requested screening of 4 adult beef cows for whole blood selenium. Two out of 4 animals were markedly deficient, and the selenium level in the third was also below the level of detection in the assay.
Adequate selenium in diet formulations, trace mineral supplements provided to pasture-fed livestock, and proper colostrum feeding all contribute to providing adequate selenium for livestock. Most NYS soils and forages are expected to be deficient in selenium.