Atrazine effects on the reproductive and digestive function of the Eared Dove (Zenaida auriculata)

BACH, N.; MANZANOS, N.; FERNÁNDEZ, N.C.; SOMOZA, G.; CHEDIACK, J. G.; CID, F. D.

Mar del Plata

Congreso; VIII Congreso Argentino de la Sociedad de Toxicología y Química Ambiental ( S E TA C , Capítulo Argentino); 2022

S E TA C , Capítulo Argentino

Atrazine (ATZ) is a widely used herbicide worldwide. It is the second most used herbicide in Argentina and environmental levels have been reported in the country. ATZ adversely affects non-target organisms, its role as endocrine disruptor affecting reproduction of amphibians have been well documented. In birds, a few reports show effects on reproduction, growth, hematological parameters, between others. But there is no information about ATZ effects in native species, and its effect on the digestive physiology are unknown. The objective of this study was to elucidate how ATZ affects reproductive and digestive function in males of Z. auricalata by evaluating variations in gonadosmatic index (GSI) and digestive enzymes activity. Additionally, hematocrit, body mass, organ mass, ALAD activity and water intake were evaluated. We used three independent groups (n=6), two groups were exposed during 15 days to 25 mg/kg and 250 mg/kg ATZ diluted in corn oil, administered by intermittent gavage, and one control group that were administered only with corn oil without ATZ. After exposure, body mass, blood extraction and removal of intestine, stomach, liver, heart and gonads were performed at the same time, during morning, to avoid effect of circadian rhythm. All organ masses were referred to body mass. ALAD activity was determined in blood, and intestinal enzymatic activity of sucrose-isomaltase (SI), maltase-glucoamylase (MG) and N-aminopeptidase (APN) was determined in proximal, medial and distal portions. RM-ANOVA was performed for digestive enzymes, hematocrit, ALAD and water intake and one-way ANOVA for body and organ masses (Tukey post-hoc test, p < 0.05). Data that failed to meet ANOVA assumptions were analyzed by Kruskall-Wallis test. No effects were observed for body and organ masses (p > 0.05) between treatments, except for GSI (p < 0.05) that resulted higher in doves exposed to 250 mg ATZ/kg. For SI, MG and APN, there were no differences (p > 0.05) between the control group and those treated with ATZ. ALAD activity, hematocrit and water intake did not show significant differences (p > 0.05) between treatments. The increment in GSI for ATZ exposed doves are in line with previous reports and could be indicative of a potential endocrine disruption. Further studies involving testes histology and circulating levels of steroid hormones are needed to understand how ATZ are affecting Z. auriculata. Supported by UNSL-PROICO 2-0820 and PICT2016-0595 to FDCid.