Dosing with 349 g calcium propionate in molasses increased plasma total calcium (Catot) concentration by 10% in lactating and non-lactating cows for periods less than 7 h, and this was not augmented by simultaneous administration of MgO or treatment 24 h earlier with 349 g calcium propionate in molasses.

The efficacy of calcium propionate at 2 different doses (0.5% and 1%) against growth and aflatoxins production by Aspergillus flavus (A-2092) was investigated in vitro on Czapek yeast extract agar at different levels of water activity (a(w)) in the range of 0.94 to 0.996a(w). A. flavus spores germinated on all calcium propionate and a(w) treatments; however, 1% calcium propionate at 0.94 a(w) delayed the germination process for up to 10 d. The growing rate of mycelia was slower (0.28 mm/d) at 1% calcium propionate and 0.94 a(w). Aflatoxins (B1, B2, G1, and G2) were also produced minimally (36.1, 1, 1.86, and 1.01 ng/g of media, respectively) at the aforementioned dose rate of calcium propionate and water activity. It was concluded that addition of calcium propionate and a(w) amelioration can prove effective tools for suppressing the germination, growth rate, and aflatoxins production by A. flavus in substrate.