Feeding behaviour of Anopheles messeae/daciae and Anopheles maculipennis s.s. in Northeastern Italy

INTRODUCTION. Since the malaria eradication, the species composition of the Anopheles maculipennis complex in North-eastern Italy has changed considerably and, to date, the two main species are represented by Anopheles messeae/daciae and Anopheles maculipennis s.s. (Calzolari et al., 2021 Sci Rep. 11: 6421). The aim of this study was to investigate the feeding choices of these two species. MATERIALS AND METHODS. Mosquitoes belonging to Maculipennis complex were collected in 19 sites in Veneto region (2018-2020) by hand aspiration and trapping. All specimens were morphologically identified and a sub-sample of engorged An. maculipennis s.l. females was identified at species level by molecular analysis. Blood meal origin was identified by PCR and cox1 gene sequencing. Feeding choice of An. messeae/daciae was investigated in a site rich in animal diversity by calculating the forage ratio (FR) and feeding index (FI). RESULTS AND CONCLUSION. A total of 1,094 engorged An. maculipennis s.l. were collected, 267 of which were identified at species level (242 An. messeae/daciae, 25 An. maculipennis s.s.). For 127 specimens (115 An. messeae/daciae and 12 An. maculipennis s.s.) it was possible to identify the origin of the blood meal, from 13 and 3 different host species respectively. Both Anopheles species fed mainly on horse (45.2% An. messeae/daciae and 33.3% An. maculipennis s.s.) and cow (30.4% An. messeae/daciae and 58.3% An. maculipennis s.s). Despite these proportions, An. messeae/daciae FR indicates host preference for buffalo (21.2), horse (8.4), man and pig (5.3); the pairwise-comparison of human FI with each host reveals its preference for humans compared to chicken (79.5), rabbit (7.3) and dog (8.0). Our results show that, due to its opportunistic feeding behavior, An. messeae/daciae shows its potential role as a vector of human and zoonotic diseases in Italy.