The ART of mating: alternative reproductive tactics and mating success in a nest-guarding fish.

Behavioural observations in the field of male Mediterranean damselfish Chromis chromis were combined with molecular analyses, using bi-parentally and maternally inherited markers, to investigate reproductive success patterns of alternative reproductive tactics (ARTs) in terms of number of eggs sired and number of females contributing to each nest. Cuckoldry was observed in every nest sampled, with at least two and up to seven sneaker males per nest. The nesting male, however, always significantly fertilized the greater number of eggs (on average 49%) in each clutch, whereas each sneaker fertilized around 7% of the clutch. The average number of females whose eggs were fertilized by nesting males was 6·76 (range 2-13), while each sneaker on average fertilized the eggs of 1·74 (range 1-8) females. Using this sibship reconstruction, some of the factors involved in the regulation of the dynamic equilibrium of reproductive success were investigated between the two ARTs shown by C. chromis males. Results show that the sneakers' reproductive success was positively linked to egg clutch size; the density of individuals in the nesting area negatively affected the size of egg clutches; the rate of defence behaviours performed by nesting males negatively influenced the number of females contributing to each nest.

Rodentolepis straminea (Cestoda: Hymenolepididae) in an urban population of Apodemus sylvaticus in the UK.

The presence of the cyclophyllidean cestode Rodentolepis straminea (Cestoda: Hymenolepididae), was confirmed by molecular DNA analysis from a wood mouse (Apodemus sylvaticus) population inhabiting urban woodland in Salford, Greater Manchester (UK) with a prevalence of 27.8%. It would appear that the only previously published record of this species in A. sylvaticus in the British Isles is that from south-west Ireland, where 24% of the wood mice examined were infected with R. straminea. This species has been recorded in studies on A. sylvaticus in continental Europe. The current report represents a new record for R. straminea on mainland Britain and a first study of helminth parasites in an urban wood mouse population.

Canine echinococcosis: genetic diversity of Echinococcus granulosus sensu stricto (s.s.) from definitive hosts.

Canids, particularly dogs, constitute the major source of cystic echinococcosis (CE) infection to humans, with the majority of cases being caused by Echinococcus granulosus (G1 genotype). Canine echinococcosis is an asymptomatic disease caused by adult tapeworms of E. granulosus sensu lato (s.l.). Information on the population structure and genetic variation of adult E. granulosus is limited. Using sequenced data of the mitochondrial cytochrome c oxidase subunit 1 (cox1) we examined the genetic diversity and population structure of adult tapeworms of E. granulosus (G1 genotype) from canid definitive hosts originating from various geographical regions and compared it to that reported for the larval metacestode stage from sheep and human hosts. Echinococcus granulosus (s.s) was identified from adult tapeworm isolates from Kenya, Libya, Tunisia, Australia, China, Kazakhstan, United Kingdom and Peru, including the first known molecular confirmation from Gaza and the Falkland Islands. Haplotype analysis showed a star-shaped network with a centrally positioned common haplotype previously described for the metacestode stage from sheep and humans, and the neutrality indices indicated population expansion. Low Fst values suggested that populations of adult E. granulosus were not genetically differentiated. Haplotype and nucleotide diversities for E. granulosus isolates from sheep and human origin were twice as high as those reported from canid hosts. This may be related to self-fertilization of E. granulosus and/or to the longevity of the parasite in the respective intermediate and definitive hosts. Improved nuclear single loci are required to investigate the discrepancies in genetic variation seen in this study.

Epidemiological updates and economic losses due to Taenia hydatigena in sheep from Sardinia, Italy.

The aim of this study was to investigate the epidemiology and transmission of Taenia hydatigena in sheep and dogs from Sardinia and the economic estimation of losses due to this metacestodosis in lambs. A total of 7781 Sarda breed lambs were examined at abattoirs for the detection of Cysticercus tenuicollis or necrotic-haemorrhagic tracks of their migration. Morphological and molecular identification of parasites was carried out. Individual faecal samples from 300 dogs were examined for copromicroscopic investigations and coproELISA assay. An overall prevalence of 14.6% for T. hydatigena cysticercosis was found in the examined lambs. In total, 10,807 parasitary tracks were found, with an abundance of 1.39 and an average intensity of 9.52. The molecular analysis of the isolates showed an overall pairwise nucleotide divergence for the CO1 and ND1 was of 0-3.1 and 0-3.3%, respectively. Low intra- and interspecific variation was recorded for C. tenuicollis isolates used in this study which suggested the absence of differentiation. Microscopic examination of dog faeces showed a total prevalence of 31.3% for endoparasites in the examined samples (94/300). Taeniid eggs were found in 8.3% of the dogs. The results of the monoclonal antibody ATH4 ELISA test showed a prevalence of 11% (33/300) for T. hydatigena coproantigens. The total economic costs related to cysticercosis amounted to almost € 330,000. The prevalence of C. tenuicollis in 14.6% of 30-40-day-old lambs highlights the high parasitic pressure by T. hydatigena in the territory of Sardinia, Italy.

Echinococcus granulosus and other intestinal helminths: current status of prevalence and management in rural dogs of eastern Australia.

OBJECTIVES: Ascertain the prevalence of intestinal helminths in rural dogs from eastern Australia and Tasmania. Identify farm management practices contributing to the perpetuation and transmission of Echinococcus granulosus. METHODS: Helminth infection in dogs was determined microscopically through faecal flotation. Infection with E. granulosus was determined via faecal antigen-capture ELISA and coproPCR. Taeniid eggs were identified using molecular methods. Data on dog management and owner understanding of hydatid disease were collected via questionnaire. RESULTS: Faeces were collected from 1425 Australian rural dogs (1119 mainland; 306 Tasmania). Eggs of hookworms were most prevalent, up to 40.2%, followed by whipworms (Trichuris vulpis), up to 21.2%. Roundworms (Toxocara canis and Toxascaris leonine) were least common, up to 6.1%. Taeniid eggs were found in 11 dogs (5 Taenia pisiformis; 2 T. serialis; 4 T. hydatigena); 2 of the T. hydatigena-infected dogs were also E. granulosus coproantigen-positive. Of the 45 dogs found to be E. granulosus coproantigen-positive, 24 were in Tasmania, 16 in NSW, 3 in Victoria and 2 in Queensland. Three Tasmanian coproantigen ELISA-positive dogs were also coproPCR-positive. The most common dog ration was commercial dry food, but half the owners fed raw meat to their dogs and some fed offal of lambs (8.9%) or mutton (7.8%). More than half (69%) of owners weighed their dogs before deworming. Few dewormed their dogs often enough to ensure they remained cestode-free and owners hunting wildlife usually left carcases where they were shot. CONCLUSIONS: E. granulosus is still present in Australian rural dogs, including Tasmania, but at low levels. Owner behaviour perpetuates transmission of cestodes.

Echinococcus and Taenia spp. from captive mammals in the United Kingdom.

Taeniid tapeworms which include Echinococcus and Taenia spp. are obligatory parasites of mammals with pathogenicity usually related to the larval stages of the life cycle. Two species (or genotypes) of Echinococcus, E. granulosus sensu stricto and E. equinus, as well as several Taenia spp. are endemic in the UK. Here we report on the occurrence of larval cystic stages of Echinococcus and Taenia spp. in captive mammals in the UK. Using molecular techniques we have identified E. granulosus (G1 genotype) in a guenon monkey and a Philippine spotted deer; E. equinus in a zebra and a lemur; E. ortleppi in a Philippine spotted deer; E. multilocularis in a macaque monkey and Taenia polyacantha in jumping rats. To the best of our knowledge this is the first report of E. multilocularis in a captive primate translocated to the UK. As far as we know these are the first reports of E. equinus in a primate (lemur) and in a zebra; as well as E. granulosus (G1 genotype) and E. ortleppi in a cervid translocated to the UK. These infections and implications of the potential establishment of exotic species of cestodes are discussed.

Cystic echinococcosis in Tunisia: analysis of hydatid cysts that have been surgically removed from patients.

Echinococcosis/hydatidosis caused by Echinococcus granulosus has a widespread distribution in the human population of Tunisia, particularly in the north-west and centre-west of the country. In a recent study, the morphological features, fertility and viability of hydatid cysts that had been excised from patients in Tunis were explored, and the E. granulosus strain or genotype involved in each case was identified from morphology of the protoscolex hooks and the results of molecular genotyping. The hepatic cysts investigated came from 41 patients [31 women and 10 men, with a mean (S.E.) age of 43.41 (14.25) years] who were treated for cystic echinococcosis, by surgery but rarely with chemotherapy, at the La Rabta Hospital in Tunis, in the 12 months ending in June 2008. Most (56%) of these patients originated from rural areas in endemic governorates. Of the 60 hepatic cysts that were studied, 38.3% were located in the right lobe of the liver and 35.0% each involved both hepatic lobes. Almost a third (31.7%) of the excised cysts were degenerating, with the rest considered viable and either multivesicular (38.3%) or univesicular (30.0%). Almost all (93.3%) of the cysts were categorized as fertile, with a mean protoscolex viability of 21.8%. Protoscolex viability was relatively high in the viable univesicular cysts with a visible cyst wall and in the multivesicular and multiseptate cysts with daughter cysts, and lowest in the cysts that appeared to be solid calcified masses. The observed variation in protoscolex viability with cyst type, in cysts excised from patients before any chemotherapy, supports the cyst classification recommended by the World Health Organization but could also be compatible with the imaging-based 'Gharbi' classification. The results of the molecular genotyping showed that all 23 cysts investigated (which came from 20 of the patients) were caused by E. granulosus of the G1 genotype (also known as the 'sheep' or 'sheep-dog' strain).

Echinococcus in the wild carnivores and stray dogs of northern Tunisia: the results of a pilot survey.

Echinococcus granulosus is endemic throughout Tunisia and E. multilocularis has previously been reported as the cause of two cases of human alveolar echinococcosis in the north-west of the country. The aim of the present study was to screen wild carnivores from the north-western Jendouba governorate and semi-stray dogs from the Siliana and Sejnane regions of northern Tunisia for these two zoonotic cestodes. The results of the coproscopy, coproELISA and coproPCR that were undertaken were compared with those of necropsy, where possible. Overall, 111 faecal samples (51 from wild carnivores and 60 from stray dogs) were tested by coproELISA for Echinococcus antigen and by coproPCR for E. granulosus and E. multilocularis species-specific DNA. All 60 dogs and seven of the wild carnivores were necropsied. Eleven (18.4%) of the dogs and one golden jackal (Canis aureus) were found positive for E. granulosus at necropsy. The jackal was found to be carrying 72 E. granulosus tapeworms, which were confirmed to be of the common sheep-dog (G1) genotype. Faecal samples from 10 (19.6%) of the wild carnivores--putatively, four golden jackals, two red foxes (Vulpes vulpes atlantica), one hyaena (Hyaena hyaena) and three genets (Genetta genetta)--gave a positive result in the Echinococcus coproELISA. In the coproPCR-based follow-up, E. granulosus DNA was detected in faecal samples from five jackals, two foxes and six stray dogs. The DNA of E. multilocularis was not, however, detected in any of the faecal samples investigated. This is the first report from Tunisia of (coproPCR-)confirmed E. granulosus infections in golden jackals and red foxes. The possible role of such wild hosts in the transmission of E. granulosus in Tunisia should be investigated further. The possibility of the active transmission of E. multilocularis in Tunisia still remains an open question.

Epidemiology and strain characteristics of Echinococcus granulosus in the Benghazi area of eastern Libya.

The incidence of surgically confirmed cystic echinococcosis in eastern Libya was estimated to be at least 4.2 cases/100,000, with significantly more female cases than male. The prevalences of infection with Echinococcus granulosus among 1087 sheep, 881 goats, 428 camels and 614 cattle from the same region, determined postmortem in abattoirs, were 20%, 3.4%, 13.6% and 11%, respectively. Infection in the livestock was age-dependent and, generally, the female animals were more often infected than the male. The measurements of rostellar hooks on protoscoleces collected from sheep and cattle were similar but significantly different from the corresponding measurements of parasites of human or camel origin. However, when a portion of the cytochrome c-oxidase subunit I (cox1) gene from each of 30 protoscolex samples from Libya (12 from cattle, three from humans, five from camels and 10 from sheep) was sequenced, the sequences were all found to be identical to that published for the common sheep strain of E. granulosus.