Effect of parasitic load on the immune response mediated by T lymphocytes in Antarctic penguins

BERTELLOTTI, M.; D'AMICO, V.; BARBOSA, A.; CORIA, N.

Barcelona

Simposio; XI SCAR Biology Symposium. Life in Antarctica: Boundaries and Gradients in a Changing Environment; 2013

Scientific Committee on Antarctic Research

Intestinal parasites suppose a cost to the host as they compete directly for nutritional resources and therefore, individuals must defend against them by mounting an immune response. Many penguin species acquire parasites through their diet, and transfer those parasites to their chicks when feeding them. High parasites loads in penguin chicks could have effects on their growth, body condition and ultimately on their survival. We evaluated the effect of parasites on cell mediated immune system in Gentoo penguin chicks (Pygoscelis papua) at Punta Stranger (25 de Mayo/King George Island, SSI). We performed an experimental deparasitation of 12 chicks with 50 mg/kg of Albendazole and 5mg/kg of Paziquantel, and kept other 10 as a control group, but providing them an equal volume of water as placebo. We measured T-lymphocytes mediated immunity in response to immunization with phytohemagglutinin (PHA). We also prepared blood smears to obtain a complete leukocyte profile in both treated and control group before and after the experiment. Twenty four hours after deparasitation, we injected 0.1 ml of 2 mg/ml of PHA (Sigma) diluted in a sterile phosphate buffer saline solution (PBS) at a marked site of the interdigital membrane of the right leg. Twenty four hours after PHA injection we found that response to PHA in treated individuals was significantly higher than the control individuals (t-test, t20 = 1.72, P