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.

An experiment was conducted to evaluate productive variables and egg component yields of laying hens in the second productive cycle that were fed a low-protein diet with increasing levels of Thr and Met. A total of 480 hens were assigned to a factorial arrangement of 3 levels of Thr (0.42, 0.48, and 0.54%) and 4 levels of Met (0.19, 0.32, 0.45, and 0.58%). Feed intake was lower (P < 0.01) and FE was greater (P < 0.05) at a dietary Thr level of 0.48%. The eggshell percentage declined linearly (P < 0.01) as the level of dietary Thr increased. Egg production, egg mass, and FE were greater at a Met level of 0.32%, and egg weight was greater when dietary Met was 0.45% (P < 0.01). The BW loss (P < 0.01) and the egg albumen percentage (P < 0.10) declined linearly, whereas the yolk percentage (P < 0.10) and eggshell percentage (P < 0.01) increased linearly as dietary Met increased. For maximum egg production and FE, the Thr intakes were 411.5 and 455.8 mg and the Thr:Lys ratios were 65 and 74%, respectively. With regard to Met, for maximum production and egg weight, the intakes of Met were 313.4 and 343.2 mg and the Met:Lys ratios were 49 and 69%, respectively. The estimated digestible Met requirement per gram of egg mass produced was 6.2 mg.

The objective of this research was to evaluate the growth performance, the apparent ileal digestibility of nitrogen and energy, the retention of nutrients and the apparent metabolizable energy corrected to zero nitrogen retention (AMEn) in broiler chickens supplemented with increasing doses of a worm leachate (WL) as a source of humic substances (HS) in the drinking water. In Exp. 1, 140 male broilers were penned individually and assigned to four WL levels (0%, 10%, 20%, and 30%) mixed in the drinking water from 21 to 49 days of age. Water was offered in plastic bottles tied to the cage. In Exp. 2, 600 male broilers from 21 to 49 days of age housed in floor pens were assigned to three levels of WL (0%, 10%, and 20%) mixed in the drinking water. The WL was mixed with tap water in plastic containers connected by plastic tubing to bell drinkers. The results of both experiments were subjected to analysis of variance and polynomial contrasts. In Exp. 1, the daily water consumption was similar among treatments but the consumption of humic, fulvic, and total humic acids increased linearly (p<0.01) as the WL increased in the drinking water. The feed conversion (p<0.01) and the ileal digestibility of energy, the excretion of dry matter and energy, the retention of dry matter, ash and nitrogen and the AMEn showed quadratic responses (p<0.05) relative to the WL levels in drinking water. In Exp. 2, the increasing level of WL in the drinking water had quadratic effects on the final body weight, daily weight gain and feed conversion ratio (p<0.05). The addition of WL as a source of HS in the drinking water had beneficial effects on the growth performance, ileal digestibility of energy, the retention of nutrients as well on the AMEn in broiler chickens; the best results were observed when the WL was mixed at levels of 20% to 30% in the drinking water.

A review of the latest research on the addition of humic substances (HSs) in the drinking water or feed of farm animals including poultry, pigs, dairy cows and calves, goats, and rabbits was carried out. The results reinforces the promoted protective action of HS on the digestive mucosa, their antioxidant properties, immunomodulatory, and anti-inflammatory attributes, the suggested microbial shift to a probiotic-type bacteria in the gut, including antiparasitic and antifungal effects, as well as their influence on the higher efficient of minerals, proteins, and lipids utilization within the body. The outstanding improvements in health, productivity, and meat and milk quality obtained from animals supplemented with HS are common features in the majority of available research. The main benefits in the gastrointestinal tract stem from the formation of protective barriers on the epithelial mucosa due to its colloidal properties and stimulation of mucin production. HS also promotes the development of probiotic microbiota and positive changes in bacterial fermentation patterns, which results in improved intestinal health and integrity. As a result, a cascade of benefits is derived within the body, reinforcing antioxidant protection responses, immunomodulation, and anti-inflammation mechanisms, as well as improving nutrient utilization efficiency. However, the truly molecular mechanisms of action of HS in the intestine and throughout the body remain unknown.

The objective of this research was to evaluate the serum concentrations of mannan-binding lectin (MBL) at different ages in Ross broilers fed increas

Different sources and inclusion levels of humic substances (HS) have been tested in broiler rations as an alternative to the addition of growth promoter antibiotics (GPA) with promising results. The current study was carried out to assess the influence of HS extracted from worm compost on broiler production parameters, carcass yield, tibia characteristics, lactic acid bacteria (LAB) counts, excretion of Eimeria oocysts, and antioxidant status of breast meat. A total of 1200 broilers were used, housed in groups of 30 per pen, and assigned to five treatments: 1 = basal diet with GPA (positive control), 2 = basal diet without GPA (negative control), 3–5 = basal diet with 0.15, 0.30, and 0.45% HS, respectively. The data was subjected to a variance analysis and orthogonal contrasts. The FI decreased linearly (p < 0.05) from 1–14, 29–42, and 1–42 days as the inclusion of HS in the feed increased. The FCR had quadratic responses (p < 0.01) from 29–42 and 1–42 days concerning the HS inclusion levels. Lactic acid bacteria was higher (p ˂ 0.05) in ten-day-old chicks with 0.45% HS in the diet. The 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity antioxidant potential decreased linearly (p < 0.05) concerning increasing HS in the feed. The results indicate that HS can be used as growth promoters in broiler feeds.