Roberto Resendes

Dissemination of antibiotic resistant Enterococcus spp. and Escherichia coli from wild birds of Azores Archipelago

Antibiotic-resistant is profoundly important to human and animal health, but the environmental reservoirs of resistance determinants are poorly understood, in particular in wild environments in remote Archipelagos. Moreover, the prevalence of antibiotic-resistant bacteria in wild bird populations is rather unknown. In the present study, we used the Azores Islands as a model study for antimicrobial resistance in a remote Archipelago, and examined the antibiotic resistance profile in enterococci and Escherichia coli recovered from faecal samples of wild birds collected in this Archipelago. A total of 138 enterococci and 115 E. coli isolates were analyzed for resistance to antimicrobial agents. Of the enterococcal isolates, Enterococcus faecalis was the most prevalent detected species (59 isolates), followed by Enterococcus faecium (40 isolates), Enterococcus durans (27 isolates) and Enterococcus hirae (12 isolates). The enterococci strains showed high percentages of resistance to tetracycline (32.6%), to ciprofloxacin (19.6%) and to erythromycin (11.6%). Lower level of resistance (<10%) was detected for ampicillin, chloramphenicol and teicoplanin. One vancomycin-resistant E. faecalis isolate was detected and harbored the vanA resistant gene. Resistance genes detected included tet(M) and/or tet(L), ermB in all tetracycline and erythromycin-resistant isolates. Resistance in E. coli isolates was detected for ampicillin, tetracycline, sulfamethoxazole/trimethoprim, streptomycin, and tobramycin. The blaTEM, aadA, aadA5, strA, strB, tet(A) and/or tet(B), and the intI genes were found in all ampicillin, streptomycin, tetracycline, and sulfamethoxazole/trimethoprim-resistant isolates respectively. The data shown in this study are essential to improve knowledge about the dissemination of resistant strains through wild birds from remote archipelagos such as the Azores Archipelago and the possible implications involved in transferring these resistances either to other animals or to humans.

Pollen morphology of Poaceae (Poales) in the Azores, Portugal

Abstract The objective of this study was to expand knowledge on the Poaceae and morphologically describe pollen grains of species occurring in the Azores Archipelago, Portugal. Pollen grains from each species under study were subjected to standard acetolysis, mounting of at least three permanent slides of each species for observations and measurement of pollen grains under light and scanning electron microscope. With regard to pollen morphology, all pollen grains were arranged as monads, with a single pore-type aperture – monoporate, featuring annulus and operculum; and outline in polar view circular, sub-circular and ovalate. Most species featured pollen size small, except for Agrostis stolonifera with pollen size very small, Brachypodium sylvaticum with pollen size medium, Zea mays with pollen size large. Species endemic to the archipelago show ornamentation pattern ranging between areolate-microechinate, microechinate, microrugulate-microechinate and verrucate-microechinate, most of which feature exine surface areolate-microechinate. Among endemic species, Rostraria azorica stood out for its oblate-spheroidal shape, whereas most species showed prolate-spheroidal shape.

Chewing Lice in Azorean Blackcaps (Sylvia atricapilla): A Contribution to Parasite Island Syndromes

Abstract:  Focusing upon chewing lice (Phthiraptera: Amblycera, Ischnocera) parasitizing blackcaps (Sylvia atricapilla) in the Azores (Portugal), we found a lower number of louse species in the Azores compared to mainland Europe. Only chewing lice host specific to blackcaps were found in the Azores. Louse prevalences were much higher in blackcaps from the Azores compared to those of various mainland populations. Chewing lice are permanent parasites of birds, and for such parasites the parasite island syndrome could be characterized by higher parasite prevalence on the islands compared to the mainland.

Genetic and morphometric diversity of the goldcrest (Regulus regulus) populations in the Azores

We studied the genetic diversity and phylogeography of the goldcrest Regulus regulus from the archipelago of the Azores (North Atlantic Ocean) based on sequences of two mitochondrial genes (cytochrome b and the NADH dehydrogenase subunit 2) and one nuclear gene in the Z-chromosome (intron 9 of the aconitase 1) from 69 individuals, and 41 birds from the Canary Islands and continental Europe for outgroup comparison. To understand the level of concordance between the genetic data and possible morphometric variability, 197 adult living birds from the seven Azorean islands where the species breeds were analysed in terms of eight morphometric characters. Our results are in accordance with previous studies, indicating a recent expansion of goldcrests throughout the archipelago and a low divergence in relation to continental Europe. Within the Azores, there is evidence of historical and/or recent gene flow among the islands populations, revealing a lack of current genetic structure within the archipelago. Only goldcrests from Flores Island seem to be genetically distinct and showed significantly larger body mass and tarsus length than birds on the other islands.

A Pollen Inventory of Endemic Species from the Azores Archipelago, Portugal

ABSTRACT The object of this study was to morphologically characterise the pollen grains from species endemic to the Azores, Portugal, in order to devise a pollen key to identify this plant group. The pollen grains from each studied species were subjected to standard acetolysis, and were mounted on at least three permanent slides for each species, in order to observe and measure the pollen grains. Pollen surface details were described from images obtained through a scanning electron microscope. A total of 43 endemic species, distributed in 22 families and 37 genera, were analysed. It was observed that most of the studied families showed specific traits of polarity, sexine ornamentation, absence or presence of aperture and shape, and can be considered eurypalynous. Families Apiaceae, Ericaceae and Poaceae showed stenopalynous traits among species. The results obtained in this work made it possible to devise a pollen key to identify of the studied species.

Genetic Diversity of the Azores Blackbirds Turdus merula Reveals Multiple Founder Events

Abstract. We assessed the genetic diversity and phylogeography of the Azores Blackbird Turdus merula, based on sequences of two mitochondrial genes (Cytochrome b and NADH Dehydrogenase subunit 2) and one nuclear gene (Aconitase 1 — intron 9) from 45 individuals and an outgroup of 15 birds from Madeira, continental west Europe and north Africa. Our results revealed the lack of genetic structure on these islands and the presence of, at least, two different lineage groups that may indicate two different founder events of the Azores by Blackbirds.

Feather mites (Acari, Astigmata) from Azorean passerines (Aves, Passeriformes): lower species richness compared to European mainland

Ten passerine species were examined on three islands of the Azores (North Atlantic) during 2013 and 2014 in order to identify their feather mite assemblages. We recorded 19 feather mite species belonging to four families of the superfamily Analgoidea (Analgidae, Proctophyllodidae, Psoroptoididae and Trouessartiidae). A high prevalence of feather mite species was recorded on the majority of the examined host species. Only three passerine species (Sylvia atricapilla, Regulus regulus and Serinus canaria) presented the same full complex of mite species as commonly occurs in the plumage of their closest relatives in continental Europe. Passer domesticus presented the same limited fauna of feather mites living in the plumage as do its co-specifics in continental Europe. Carduelis carduelis bears the same feather mite species as do most of its continental populations in Europe, but it lacks one mite species occurring on this host in Egypt. Turdus merula, Pyrrhula murina and Fringilla coelebs are missing several mite species common to their continental relatives. This diminution could be explained by the founder effect, whereby a limited number of colonizing individuals did not transport the full set of feather mite species, or by the extinction of some mite species after initially having reached the Azores. The only individual of Motacilla cinerea sampled in this study presented a new host record for the mite species Trouessartia jedliczkai.

Ticks on passerines from the Archipelago of the Azores as hosts of borreliae and rickettsiae

We examined the presence of borreliae and rickettsiae bacteria in ticks from wild passerine birds on three islands of the Archipelago of the Azores, the westernmost region of Palearctic. A total of 266 birds belonging to eight species from seven families were examined on São Miguel, Santa Maria and Graciosa islands in 2013. Ticks collected from these birds consisted of 55 Ixodes frontalis (22 larvae, 32 nymphs, 1 adult female) and 16 Haemaphysalis punctata nymphs. Turdus merula and Erithacus rubecula were the birds most infested with both tick species. Three T. merula in Santa Maria were infested with 4 I. frontalis infected with Borrelia turdi. No rickettsiae were found in the ticks. We report for the first time the presence of I. frontalis and B. turdi on the Azores islands and we showed that the spatial distribution reaches further west than previously thought.