The ability to adsorb zearalenone by five strain of lactic acid bacteria was evaluated: four strains of Lactobacillus spp. isolated from pig rectal swabs and one commercial strain (Lactobacillus rhamnosus). Several factors affecting the adsorption capacity were evaluated in order to improve the adsorption of the mycotoxin by bacteria. The stability of the zearalenone–bacteria complex was analyzed. In every case, bacterial adsorption capacity was higher than 40.0%. The strain showing the highest adsorption (68.2%) was selected for the following steps of this research. The adsorption percentages obtained after processing 6.5 and 7.5 mL MRS broth were 57.40% + 3.53 and 64.46% + 0.76, respectively. The stability of zearalenone–bacteria complex was evaluated by successively rinsing. In the first rinsing step 42.26% + 0.414 was still bound. In the second rinsing step 25.12% + 0.664 was still bound, whereas 15.82% + 0.675 remained in the pellet after the third rinse. Results obtained demonstrated that Lactic Acid Bacteria has capacity to adsorb zearalenone. Finally adsorption was increased using a higher volume of initial broth. These results could be used to design a new lyophilized powder for detoxification, using lactic acid bacteria as potential zearalenone adsorbents.

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Background: Bovine campylobacteriosis is a venereal disease due to infection with Campylobacter fetus venerealis. It causes mainly reproductive failures that lead to considerable economic losses. Objective: To perform a histopathological description of the mucosa from reproductive organs of heifers experimentally infected with Campylobacter fetus venerealis. Methods: Twelve 15-18-months-old Aberdeen Angus heifers were treated for estrous synchronization and exposed to natural breeding. They were then randomly divided into two groups: group A (n=9) was inoculated with C. fetus venerealis; group B (n=3, control) was inoculated with a placebo. Ultrasonography was performed at days 29, 38, and 42 post-breeding, and plasmatic progesterone levels were quantified using ELISA to confirm pregnancies. Animals in group A with plasma progesterone levels below 1 ng/mL and/or diagnosed as non-pregnant were further divided into three subgroups: A1 (n=4), euthanized at day 30 post-breeding; A2 (n=3), euthanized at day 40 post-breeding and A3 (n=2), euthanized at day 55 postbreeding. Heifers from group B, all diagnosed as pregnant, were euthanized each at day 30, 40, and 55 days post-breeding as well. Histological sections from every group were taken from oviducts, uterus, and vagina. Results: Lymphocytic inflammation was the most common lesion in all infected heifers. Trophoblast cells were found in the non-pregnant heifers euthanized at days 40, and 55 post-breeding. The inflammatory process with the presence of lymphoid cells probably altered the balance in the activity of maternal lymphoid cells, as well as gene expression of the trophoblast, finally affecting the embryo survival. Conclusion: This work contributes to the understanding of the histopathological process involved in post-mating infection of Campylobacter fetus bovine.