Corrigendum: Evaluation of the efficacy of humic acids to counteract the toxic effects of aflatoxin B1 in turkey poults.

[This corrects the article DOI: 10.3389/fvets.2023.1276754.].

Evaluation of the efficacy of humic acids to counteract the toxic effects of aflatoxin B1 in turkey poults.

This study aims to evaluate the efficacy of humic acid (HA) from worm compost as an adsorbent for aflatoxin B1 (AFB1) in turkey poults. The experiment involved the inclusion of 0.25% (w/w) HA in the diet of turkey poults consuming aflatoxin-contaminated feed (250 ng AFB1/g). A total of 350 1-day-old female Nicholas-700 turkey poults were randomly allocated to five equal groups: negative control (basal diet); positive control (basal diet + 250 ng AFB1/g; HA (basal diet + 0.25% HA); HA + AFB1 (basal diet + HA + 250 ng AFB1/g); and zeolite + AFB1 (basal diet + 0.25% zeolite + 250 ng AFB1/g). Each group had seven replicates of 10 poults (n = 70). The impact of HA addition was evaluated in terms of performance parameters, relative organ weights, liver histological lesions, and serum biochemical and hematological constituents. In general, the addition of HA improved body weight (BW), body weight gain (BWG), and feed conversion rate (FCR). Furthermore, HA effectively mitigated the toxic effects caused by AFB1 in the majority of the analyzed variables. The results indicated that HA effectively counteracted the AFB1-induced toxic effects in turkey poults. Based on these findings, it can be concluded that HA is capable of removing AFB1 from the contaminated diet.

Humic Acids Preparation, Characterization, and Their Potential Adsorption Capacity for Aflatoxin B1 in an In Vitro Poultry Digestive Model.

Vermicompost was used for humic acid (HA) preparation, and the adsorption of aflatoxin B1 (AFB1) was investigated. Two forms of HA were evaluated, natural HA and sodium-free HA (SFHA). As a reference, a non-commercial zeolitic material was employed. The adsorbents were characterized by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), energy-dispersive X-ray spectroscopy (EDS), zeta potential (ζ-potential), scanning electron microscopy (SEM), and point of zero charge (pHpzc). The adsorbent capacity of the materials when added to an AFB1-contaminated diet (100 µg AFB1/kg) was evaluated using an in vitro model that simulates the digestive tract of chickens. Characterization results revealed the primary functional groups in HA and SFHA were carboxyl and phenol. Furthermore, adsorbents have a highly negative ζ-potential at the three simulated pH values. Therefore, it appears the main influencing factors for AFB1 adsorption are electrostatic interactions and hydrogen bonding. Moreover, the bioavailability of AFB1 in the intestinal section was dramatically decreased when sorbents were added to the diet (0.2%, w/w). The highest AFB1 adsorption percentages using HA and SFHA were 97.6% and 99.7%, respectively. The zeolitic material had a considerable adsorption (81.5%). From these results, it can be concluded that HA and SFHA from vermicompost could be used as potential adsorbents to remove AFB1 from contaminated feeds.

Effects of humic acids on the recovery of different bacterial strains in an in vitro chicken digestive model.

Humic acids (HA) have been evaluated as growth promoters in poultry, but their effects on the gut microbiota remains controversial using in vitro and in vivo models. The objective of this study was to determine the effect of HA extracted from a wormcompost on the recovery of bacteria: Salmonella Enteritidis (S. Enteritidis), Escherichia coli (E. coli), Clostridium perfringens (C. perfringens), Bacillus subtilis (B. subtilis) and Lactobacillus salivarius (L. salivarius) using an in vitro chicken digestive system. Independent in vitro trials were run for each bacteria using six treatments: 1) Negative control with no bacteria added (Control-), 2) Positive control added with bacteria (Control+), 3) 0.1% HA + bacteria, 4) 0.2% HA + bacteria, 5) 0.5% HA + bacteria and 6) 1% HA + bacteria. Data was subjected to analysis of variance and linear regression. In the crop, S. Enteritidis was lower, C. perfringes and B. subtilis were not affected by HA, while E. coli and L. salivarius were higher at 0.5 and 1% HA inclusion (P ≤ 0.0001). In the proventriculus, S. Enteritidis, E. coli and B. subtilis were higher at 0.5 and 1% HA inclusion (P ≤ 0.0001); C. perfringens and L. salivarius were not affected by HA. In intestine, significant increases of all bacteria strains were observed (P ≤ 0.0001). In conclusion, the results suggests that HA can be used as prebiotic, but their mechanisms of action to stimulate the growth of gut bacteria remains to be elucidated.