An Algoclay-Based Decontaminant Decreases Exposure to Aflatoxin B1, Ochratoxin A, and Deoxynivalenol in a Toxicokinetic Model, as well as Supports Intestinal Morphology, and Decreases Liver Oxidative Stress in Broiler Chickens Fed a Diet Naturally Contaminated with Deoxynivalenol

Abstract

The aims of this study were (i) to determine the effect of an algoclay-based decontaminant on the oral availability of three mycotoxins (deoxynivalenol; DON, ochratoxin A; OTA, and aflatoxin B₁; AFB₁) using an oral bolus model and (ii) to determine the effect of this decontaminant on the performance, intestinal morphology, liver oxidative stress, and metabolism, in broiler chickens fed a diet naturally contaminated with DON. In experiment 1, sixteen 27-day-old male chickens (approximately 1.6 kg body weight; BW) were fasted for 12 h and then given a bolus containing either the mycotoxins (0.5 mg DON/kg BW, 0.25 mg OTA/kg BW, and 2.0 mg AFB₁/kg BW) alone (n = 8) or combined with the decontaminant (2.5 g decontaminant/kg feed; circa 240 mg/kg BW) (n = 8). Blood samples were taken between 0 h (before bolus administration) and 24 h post-administration for DON-3-sulphate, OTA, and AFB₁ quantification in plasma. The algoclay decontaminant decreased the relative oral bioavailability of DON (39.9%), OTA (44.3%), and AFB₁ (64.1%). In experiment 2, one-day-old male Ross broilers (n = 600) were divided into three treatments with ten replicates. Each replicate was a pen with 20 birds. The broiler chickens were fed a control diet with negligible levels of DON (0.19-0.25 mg/kg) or diets naturally contaminated with moderate levels of DON (2.60-2.91 mg/kg), either supplemented or not with an algoclay-based decontaminant (2 g/kg diet). Jejunum villus damage was observed on day 28, followed by villus shortening on d37 in broiler chickens fed the DON-contaminated diet. This negative effect was not observed when the DON-contaminated diet was supplemented with the algoclay-based decontaminant. On d37, the mRNA expression of glutathione synthetase was significantly increased in the liver of broiler chickens fed the DON-contaminated diet. However, its expression was similar to the control when the birds were fed the DON-contaminated diet supplemented with the algoclay-based decontaminant. In conclusion, the algoclay-based decontaminant reduced the systemic exposure of broiler chickens to DON, OTA, and AFB₁ in a single oral bolus model. This can be attributed to the binding of the mycotoxins in the gastrointestinal tract. Moreover, dietary contamination with DON at levels between 2.69 and 2.91 mg/kg did not impair production performance but had a negative impact on broiler chicken intestinal morphology and the liver redox system. When the algoclay-based decontaminant was added to the diet, the harm caused by DON was no longer observed. This correlates with the results obtained in the toxicokinetic assay and can be attributed to a decreased absorption of DON.

Keywords: Fusarium; algae; broiler chickens; intestine; liver; mycotoxins; production performance.

Figure 1

Mean (±SD) plasma concentration–time curve of AFB₁ (a) and OTA (b) and instrument response–time curve of DON-3S (c) up to 8 h (AFB₁), 24 h (OTA), and 12 h (DON-3S) after an oral bolus administration of AFB₁ (2.0 mg/kg BW), OTA (0.25 mg/kg BW), and DON (0.5 mg/kg BW) with and without the algoclay-based decontaminant; p.a. = post-administration; red = control, and blue = decontaminant.

Figure 2

Illustrative images of PAS-haematoxylin-stained sections of jejunum from broiler chickens fed the experimental diets. (A–C): Jejunum sections of 14-day-old broiler chickens fed the control, DON, and DON + algoclay-based decontaminant diets, respectively. In (B), an insert shows haemorrhagic areas in the villus (black arrows). (D–F): Jejunum sections of 28-day-old broiler chickens fed the control, DON, and DON + algoclay-based decontaminant diets, respectively. In Panels (D,E), it is possible to observe damage in the villus tip of the jejunum. (G–I): Jejunum sections of 37-day-old broiler chickens fed the control, DON, and DON + algoclay-based decontaminant diets, respectively. Scale bars = 500 μm.