Efficacy of Nigella sativa in alleviating benzo[a]pyrene-induced immunotoxicity in broilers.

The immune response of broiler chickens exposed to intra-tracheal (i.t.) administration of benzo[a]pyrene (BaP) with and without Nigella sativa (Ns) supplementation was investigated. A total of 120 day-old chicks were divided into four groups comprising 30 birds each, into a control, Ns, BaP, and BaP+Ns group. Immune responses to Newcastle disease (ND) were evaluated by haemagglutination inhibition (HI), phytohaemagglutinin (PHA) skin test and carbon clearance assay (CCA). In most instances, there was a significant increase (p<0.05) in the ND-HI antibody titers, PHA skin-swelling response and phagocytic activity in the BaP + Ns group compared to that of the BaP group. Likewise, organ weight and indices of the spleen, bursa of Fabricius and thymus of birds from the BaP + Ns group were also higher (p<0.05) than that of the BaP group from day 1 until day 21. It is concluded that exposure to BaP may exert adverse effects on the immune system of broilers which may increase their susceptibility to disease, and Ns supplementation significantly reduces these alterations.

Pulmonary modulation of benzo[a]pyrene-induced hemato- and hepatotoxicity in broilers.

Aftermath in several air pollution episodes with high concentrations of polycyclic aromatic hydrocarbons did not significantly affect health and performance of broilers despite its renowned sensitivity to polycyclic aromatic hydrocarbons. The aim of the study was to elucidate the previous lack of response in birds exposed to such severe episodes of air pollution. Benzo[a]pyrene (BaP) was used to simulate the influence of air pollution on hematology, selected organ function, and oxidative stress in broilers. One-day-old chicks were assigned to 5 equal groups composed of a control group, tricaprylin group, and 3 groups treated with BaP (at 1.5 microg, 150 microg, or 15 mg/kg of BW). The BaP was intratracheally administered to 1-d-old chicks for 5 consecutive days. The hematology, liver and kidney function, P450 activity, and malondialdehyde level especially in the group receiving 15 mg of BaP/kg of BW demonstrated evidence of hemato- and hepatoxicity via BaP-induced oxidative stress. The deleterious effect of exposure to high concentration of BaP in broiler chickens was probably due to the anatomy of this species and the half-life of BaP. Although the effect of BaP may be transient or irreversible, pathogen challenges faced during the period of suppression may prove fatal.