Dietary modulation of immune responses by ascorbic acid in healthy and cadmium-induced immunocompromised chickens

The assessment of immunological changes induced in chickens by feeding 50 mg cadmium per 1 kg of diet from hatching to 30 days of age was studied. Furthermore, the modulatory effects of different supplemental doses of ascorbic acid (100 and 1000 mg per 1 kg of diet) were investigated. The observed immunocompromise in chickens continuously exposed to cadmium resulted in a decreased growth rate and disturbance of immune responses, both on nonspecific and specific levels. The effect of supplements 100 and 1000 mg of ascorbic acid per 1 kg of diet differed. The low dosage of ascorbic acid had immunostimulative action in healthy cadmium-untreated chickens, provided correction of compromised immunity, and increased tolerance of the birds to subtoxic cadmium intake. In contrast, the higher supplement of ascorbic acid had a slight or no effect on healthy birds and either caused no significant shifts in immunological indices or manifested synergistic effect combined with cadmium.