Effect of rare earth elements on beef cattle growth performance, blood clinical chemical parameters and mitogen stimulated proliferation of bovine peripheral blood mononuclear cells in vitro and ex vivo.
Rare earth elements (REE) are possible performance enhancers in animal production, but little is known about their effects on ruminants. Therefore a feeding trial was conducted with 40 fattening bulls who received 0, 100, 200 or 300mg REE-citrate/kg dry matter (DM), containing 34.30% La, 58.09% Ce and 7.61% other REE. DM intake was measured daily and live weight weekly. Ex vivo ConcanavalinA (ConA)-stimulated cell proliferation of peripheral blood mononuclear cells (PBMC) was tested by MTT and alamar blue (AB) assay. Serum was analysed for clinical chemical parameters, ion (Mg, Ca and P) and REE concentrations. The effects of LaCl(3), CeCl(3), NdCl(3) and YCl(3) on ConA-stimulated proliferation of PBMC were tested in vitro, using MTT and AB assay. REE-citrate supplementation did affect DM intake, but not live weight gain, clinical chemical parameters, and ion concentrations significantly. In REE-300 group ex vivo proliferation of PBMC was significantly increased. In vitro ConA-stimulated proliferation decreased with rising REE-chloride concentrations. At least at the highest tested concentration (approximately 290μM) the inhibition reached significance. Proliferation of non-stimulated PBMC was not affected dose-dependently. REE affect the proliferation of PBMC, thus an effect on the bovine immune system is possible. However, the great differences in effective doses in vitro and ex vivo (serum REE concentrations) might explain the different results from the experiments.
Institute of Animal Nutrition, Friedrich-Loeffler-Institute, Federal Research Institute for Animal Health, Bundesallee 50, 38116, Braunschweig, Germany.
Lydia
L
Renner
Annett
A
Schwabe
Susanne
S
Döll
Martin
M
Höltershinken
Sven
S
Dänicke
D000821:Animal Feed / Q000032:analysis; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001774:Blood Chemical Analysis; D001835:Body Weight / Q000187:drug effects; D002417:Cattle; D049109:Cell Proliferation / Q000187:drug effects; D002469:Cell Separation; D004396:Coloring Agents; D006128:Growth / Q000187:drug effects*; D066298:In Vitro Techniques; D008297:Male; D008674:Metals, Rare Earth / Q000097:blood / Q000494:pharmacology*; D008934:Mitogens / Q000494:pharmacology*; D009000:Monocytes / Q000187:drug effects*; D013778:Tetrazolium Salts; D013844:Thiazoles; D015430:Weight Gain / Q000187:drug effects
D004396:Coloring Agents; D008674:Metals, Rare Earth; D008934:Mitogens; D013778:Tetrazolium Salts; D013844:Thiazoles; C022616:thiazolyl blue