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This study evaluated the germination capacity of Pochonia chlamydosporia (VC4) fungus after its passage through the gastrointestinal tract of domestic chickens and its interaction with Ascaridia galli and Heterakis gallinarum eggs. Twenty-two domestic chickens were divided in two groups: control group (G1) received shredded corn substrate without VC4; and treatment group (G2) received a single dose of 29 g corn substrate containing 3.3 × 10 6 conidia/chlamydospores (VC4). Subsequently, chicken fecal samples were collected at intervals of 0, 6, 8, 10, 12, 18 and 24 h. Petri dishes from fecal samples of the treated group (G2) were subdivided (G2a and G2b), and then replicated in 2% agar-water medium for the microbiological test. After VC4 growth, approximately 200 eggs of A. galli (G2a) and H. gallinarum (G2b) were added to each subgroup to evaluation of ovicidal activity. There was fungal viability after passage through chicken gastrointestinal tract and egg predation of 59.9% and 43.2% for A. galli and H. gallinarum, respectively. The present work demonstrates the ability of the fungus P. chlamydosporia to survive after passing through the gastrointestinal tract of domestic chickens, an extreme environment (low pH, enzymes, microbiota and mechanical action), and still germinate after being excreted with feces., (Copyright © 2020 Elsevier Inc. All rights reserved.)

In order to evaluate the differential absorption and toxicity of arsenate (As V ) and arsenite (As III ), Lemna valdiviana plants were grown in a nutrient solution and subjected to 0.0 (control); 0.5; 1.0; 1.5; 2.0; 3.0; 4.0; 5.0 and 7.5 mg L -1 of As III or As V for three days. Exposure to both chemical forms resulted in As bioaccumulation, although As III -grown plants showed higher As content in tissues. In As V -grown plants, the relative growth rate (RGR) decreased to 50%, at a concentration of 4.0 mg L -1 , while for treatments with As III , the same decrease was observed at 1.0 mg L -1 . The tolerance index decreased with increasing concentrations, with lower values for As III . Plants treated with As III showed increased superoxide anion levels, whilst higher levels of hydrogen peroxide were present in AsV-treated plants. Moreover, malondialdehyde (MDA) levels were higher for plants subjected to As III when compared to As V at lower concentrations. Concentrations of 1 mg L -1 of As III and 4 mg L -1 of As V showed equivalent MDA levels. Superoxide dismutase and catalase activities were increased at low concentrations and were inhibited at higher concentrations of As III and As V , whereas peroxidase activity was positively modulated by increased As III or As V concentrations. In conclusion, L. valdiviana plants took up and accumulated arsenic as As III or As V , demonstrating the potential for phytoremediation of this metalloid. Furthermore, As III -exposed plants showed enhanced toxicity when compared to As V , at the same applied concentration, although toxicity was more related to internal As concentrations, regardless of the chemical form applied.