External and intestinal parasites of the Austral thrush Turdus falcklandii (Aves, Turdidae) in central Chile

A total of thirty Austral thrushes Turdus falcklandii Quoy & Gaimard, 1824 (Turdidae) carcasses were brought to the Departamento de Ciencia Animal, Facultad de Ciencias Veterinarias, Universidad de Concepción, to be examined for ectoand endoparasites. Ectoparasites were found on 20% (6/30) of the thrushes and belonged to species Brueelia magellanica Cichino, 1986 (Phthiraptera), Menacanthus eurysternus Burmeister, 1838 (Phthiraptera) and Tyrannidectes falcklandicus Mironov & González-Acuña, 2011 (Acari). Endoparasites were isolated from 26.6% (8/30) of the birds and identified as Lueheia inscripta Westrumb, 1821 (Acanthocephala), Plagiorhynchus cylindraceus Goeze, 1782 (Acanthocephala), Wardium sp. sensu Mayhew, 1925 (Cestoda), Dilepis undula (Cestoda) Schrank, 1788, and Zonorchis sp. (sensu Travassos, 1944) (Trematoda). To our knowledge, all endoparasites collected in this study are new records in T. falcklandii and expand their distributional range to Chile.


Materials and Methods
Thirty thrush carcasses were collected in different localities of the Biobío region, Chile, in the period 2004-2010.Carcasses were brought to the Departamento de Ciencia Animal, Facultad de Ciencias Veterinarias, Universidad de Concepción, Chillán, and stored at -20°C until examination.Thrushes examined in this study died of anthropogenic causes common to birds living in the countryside, such as poisoning, dog attacks, and illegal hunting.
External inspection of carcasses included a rigorous examination of their feathers in search of ectoparasites.Specimens found were preserved in ethanol (70%) for future identification.Lice (Phthiraptera) collected were processed using KOH (20%) and dehydrated in a series of alcohols (40, 80 and 100%) and then mounted using Canada balsam as described in Price et al. (2003).Mites (Acari) were cleared using Nesbitt's solution (40g of chloral hydrate, 25 mL of distilled water and 2.5 mL of hydrochloric acid) for 72 h and were later mounted in Berlese solution (KRANTZ, 1978).Ectoparasites species and sex were identified using keys indicated in Burmeister (1838) and Cicchino (1986Cicchino ( , 1987)).To evaluate the presence of endoparasites, thrushes were necropsied following procedures described in Kinsella & Forrester (1972).Acanthocephala were cleared in temporary mounts of 80% phenol, identified, and then returned to the preservative.Cestodes and trematodes were and stained in Semichon's carmine stain and mounted in Canada balsam (PRITCHARD & KRUSE, 1982).Helminths were identified following descriptions in Yamaguti (1958Yamaguti ( , 1959Yamaguti ( , 1963) ) and Khalil et al. (1994).
Basic population parameters of prevalence, mean intensity, range, and mean abundance were calculated for ectoparasites and endoparasites collected.Prevalence was defined as the percentage of hosts infested by a particular parasite species.Mean intensity is represented by the mean number of parasites found in infected hosts.Range is the difference in the number of parasites collected in the most and least infested/infected hosts.Mean abundance is the number of individuals of a particular parasite from single host.Calculations were performed according to Bush et al. (1997).Additionally, ecto-and endoparasites collected were digitally measured using KS100 Imaging system 3.0 (Carl Zeiss Vision GmbH, Hallbergmoos, Germany).

Ectoparasites
Ectoparasites were present on 20% (6/30) of the thrushes examined.Lice were identified on 20% (6/30) with a total of 672 individuals collected.Mites were found on 3.3% (1/30) of the birds examined with only a single specie of mite collected.Population parameters for ectoparasites are indicated in Table 1.
They also indicate that many other Brueelia species are probably present on Chilean birds.

Endoparasites
Of the birds examined, 26.6% (8/30) were host to at least one kind of endoparasite.Two Acanthocephala, two Cestoda, and a single Trematoda were identified.Population parameters for endoparasites are indicated in Table 3.

Table 1 .
Range, mean intensity, mean abundance and prevalence of ectoparasites collected from the Austral thrush (Turdus falcklandii), Chile.

Table 3 .
Range, mean intensity, mean abundance and prevalence of endoparasites collected from the Austral thrush (Turdus falckandii), Chile.