Individual Acute Exposures to Low Concentrations of Cadmium, Chromium, Lead, and Nickel Affect Oxidative Stress and Pathological Markers in Fruit Bats

We investigated the effects of heavy metals on fruit-eating bats. Artibeus lituratus, a species that is not endangered, received a 1.5 mg/kg intraperitoneal (ipi) injection of cadmium (Cd), chromium (Cr), lead (Ld), or nickel (Ni). After 96 h, Ni-exposed bats showed oxidative stress in the liver and testes; the kidneys showed increased vascular congestion. Pb-exposed bats showed lower glutathione <i>S</i>-transferase (GST) activity in all tested tissues and a decreased percentage of normal cells in the seminiferous tubules in the testes. Bats exposed to Cr showed lower GST activity in the kidneys and testes, higher leukocyte infiltrate in the liver, and higher vacuolization in the testes. Cd-exposed bats showed lower GST activity in all tissues, higher leucocyte infiltrate in the kidneys, and a lower percentage of normal cells in the testes. Necrotic and lipidic areas in the liver were observed in Pb-exposed and Ni-exposed bats. We propose the following toxicity order for fruit-eating bats: Ni > Pb > Cr = Cd.