R. Ruiz de Ybáñez

Epidemiological study of non-systemic parasitism in dogs in Southeast Mediterranean Spain assessed by coprological and post-mortem examination.

The prevalence and risk factors of non‐systemic canine ecto‐ and endoparasitism and anthelminthic use in Murcia located at the centre of the Spanish Mediterranean coastal arch, was investigated by coprology and necropsy in up to 275 pet, city shelter and stray dogs in 2001–2004. Faecal parasite stages were detected in 25% of dogs. Species frequency was 6–10% for Toxocara canis, Ancylostomatidae spp., Toxascaris leonina and Isospora canis, and 0.4–1% for Trichuris vulpis, Giardia lamblia, and Dipylidium caninum. Logistic regression indicated that the risk of intestinal parasitism was highest for dogs ≤1 year old, in the middle to low weight range and kept at the city shelter. Although risk factors varied according to the species, T. canis was most common in <1 year old and Ancylostomatidae spp. was more prevalent in older dogs. This suggests that the dominant species was Uncinaria spp. and not the more zoonotically important Ancylostoma spp. This was further supported by necropsy findings; however, the degree of agreement between post‐mortem and coprological examination for intestinal parasites was generally poor. Necropsy revealed 10%G. lamblia, 12%Taenia spp. 38%D. caninum infections. Fleas, ticks and lice were also found in 38%, 6% and 2% of necropsied stray dogs. These results demonstrate the need for an urgent parasite control programme at the city dog shelter and the need to improve the owner’s education on zoonotic risks, the proper use of anthelminthics, and other parasite control practices.

Questionnaire survey on Canine Leishmaniosis in southeastern Spain

A veterinary practitioners questionnaire survey on Canine Leishmaniosis (CanL) was carried out in southeast Spain to provide information on disease incidence, diagnosis and recommended preventive measures. A third of 101 responding veterinarians reported seeing more than 20 CanL cases during the previous year and clinical signs considered frequent or very frequent included weight loss, areas of exfoliative dermatitis, lymphadenomegaly, kidney dysfunction, onychogryphosis, cutaneous ulcers, anaemia, asthenia and apathy. Almost a third of veterinarians reported diagnosing CanL solely on the basis of lack of response to treatment for other chronic illnesses. The frequency of individual signs did not always reflect their diagnostic value. The majority of veterinarians, considered lymphadenomegaly, exfoliative dermatitis, onychogryphosis, weight loss and epistaxis to be the best disease indicators. However, up to 93% of veterinarians reported using laboratory tests to confirm infection, including indirect (biochemical and antibody assays) and direct (PCR and microscopy) methods. Among recommended measures to prevent CanL, insecticide impregnated collars and topical spot-on capsules were prescribed by 92% and 74% of respondents; however, at least 11% of veterinarians believed existing CanL preventive measures were ineffective. Multivariable statistical analysis indicated that seeing more than 20 CanL cases during the previous year was independently associated with being located in Alicante province, having a rural clientele and recognising that dogs with no other sign but a lack of response to other chronic disease treatments may be infected with CanL. There was a weak association between CanL incidence and rainfall in the months prior to typical sandfly peak abundance.

Geographical Variation and Factors Associated to Seroprevalence of Canine Leishmaniosis in an Endemic Mediterranean Area

This article retrospectively analyses the spatial distribution and dog‐ and environmental‐level risk factors associated to Leishmania infantum seroprevalence among 807 asymptomatic dogs in the Municipality of Crevillente in Alicante in southeast Spain in 1999. They represented 60% of the dogs in this 103 km2 area, with a human census of 27 034 people and 90% lived in Crevillente town. The estimated seroprevalence (95% confidence interval) in 714 dogs ≥1‐year old was 22% (19–25) however; it was 12% (8–15) in town dogs and 0–100% in other administrative zones. High–medium seroprevalence zone clustered along a northeast–southwest fringe and around the town. They comprised the highest and driest inhabited part of the municipality, where farmland was interspersed by residential detached houses, whilst null–low seroprevalence zones included larger farmland extensions and two small rural villages. Predominant vegetation and ground soil type were bush, non‐irrigated fruit trees and conglomerate crust and sandstone in medium–high seroprevalence zones and irrigated grassland and fruit trees and colluvial deposits in null–low seroprevalence zones. Random effects logistic regression indicated that the prevalence of infection with L. infantum was higher for dogs sharing residence with infected dogs, increased until 5–6 years old and with body weight and was associated to increasing conglomerate crust and low surface water in the dog’s zone of residence. The study confirms that L. infantum infection is endemic in this part of Spain and shows that prevalence can vary significantly within a small area depending on specific demographic and environmental factors conditioning the habitat of the local L. infantum vector, Phlebotomus perniciosus. It suggests similar low‐scale variability is present in other geographically variable endemic areas and should be investigated to design Leishmaniosis risk maps and cost‐effective, evidence‐based, targeted control interventions.

Variable performance of a human derived Sarcoptes scabiei recombinant antigen ELISA in swine mange diagnosis

The performance of an indirect ELISA test based on Sarcoptes scabiei var hominis recombinant antigen Ssλ20ΔB3 (rec-ELISA), to diagnose pig mange was investigated in 15 experimentally infected and non-infected pigs and 692 commercial pigs from 16 herds in southeast Spain. These latter animals included 6-7 month old fatteners (13 herds), 11-12 month old replacement sows (1 herd) and ≥24 month old breeding sows (7 herds). All pigs were examined for mites in ear skin scrapings and the presence of S. scabiei-associated macroscopic dermatitis; moreover, fatteners were also tested for antibodies against porcine viruses including: Aujeszky disease virus (ADV), swine influenza virus (SIV), type 2 porcine circovirus (PCV2) and porcine respiratory and reproductive syndrome virus (PRRSV). S. scabiei and chronic hyperkeratotic dermatitis were detected in breeding sows from 6 herds. Mite prevalence in other pigs was 83% in replacement sows, 0% in 7 fatteners herds and 3-82% in other fatteners herds. All fattener herds had pigs with acute hypersensitivity dermatitis and the percentage of affected pigs and lesion area was significantly greater in S. scabiei infected ones. Rec-ELISA relative optical densities (RODs) were greater in older than in young pigs, as well as in infected compared to non-infected pigs. However, RODs differed significantly between infected individuals, regardless of age and origin (commercial or experimental) and the herd prevalence of S. scabiei. Low repeatability between ELISA microtiter plates, suggesting variable specific antibody binding to antigen, are likely partly responsible for ROD variation. Other potential causes of variation were examined in fatteners using random effects logistic regression analysis, after defining a seropositivity threshold value with receiver-operating characteristics (ROC) analysis. The logistic model indicated that seropositivity was associated with large dermatitis areas and with the only herd with low PCV2 seroprevalence. Pigs with more extensive dermatitis may have older infections and more rec-ELISA detectable antibodies. The possibility that PCV2, a recognized immunosupressor, depresses antibody production against S. scabiei infection merits further attention. In summary, results indicate some potential of the studied rec-ELISA as a complementary tool for herd-level swine mange diagnosis, and that work to reduce internal and external sources of assay variation is essential.

On the aggregated nature of chronic Sarcoptes scabiei infection in adult pigs.

The prevalence and body distribution of Sarcoptes scabiei and associated dermatitis was investigated in sows and boars from four herds with long standing mange. Macroscopic hyperkeratotic dermatitis (crusted mange) was present in 1-6% of herd sows. Mite estimated prevalence (95% CI) in ear scrapings was 11% (6-17%) including 100% (13/13) and 2% (3/134) in sows with and without crusted mange, respectively, and the later had very few mites compared to the former. S. scabiei body distribution and dermatitis were further investigated in 59-64 skin scrapings/sow taken post-mortem from four culled sows including two (sows 1 and 2) with and two (sows 3 and 4) without crusted mange. The proportion of skin samples with eggs, instars or adults was 59% in sow 1, 84% in sow 2, 0% in sow 3 and 3% in sow 4. S. scabiei distribution in sows 1 and 2 ranged from being present in all skin ear and head samples to absent in those from the inner side of the limbs and mammary glands. Crusted lesions were observed in the skin of the ears, neck and lower limbs and contained the largest mite populations. Histopathological analysis of skin samples identified mites, inflammatory cellular infiltrate (mainly lymphocytes, neutrophils and eosinophils) and hyperkeratosis, acanthosis and spongiosis in 78%, 54%, 20% and 25% of samples from sows 1, 2, 3 and 4, respectively, being lesion severity positively associated to mite presence. The study provides further evidence that in herds with long-standing exposure to S. scabiei, infection becomes highly overdispersed with large mite populations present only in a few pigs and in specific body areas. Although the reasons for mite aggregation have not been identified, it is important controlwise because treating or eliminating a few and easy to identify heavily infected adult pigs, should markedly decrease the herds parasite load and reduce the use of acaridal drugs.

Intestinal myiasis in a dog

form of the disease is characterised by microabscessations in the brainstem, (Jubb and Huxtable 1993). In llamas, however, the lesion appears to manifest as suppurative meningitis (Van Metre and others 1991). In the present case, the llama not only had suppurative meningitis, but also revealed multifocal acute necrotising splenitis. The llama showed abnormal neurological signs after surgery, and it may be that the surgical procedure led to septicaemia and localisation of the bacteria in the meninges. However, the meningeal changes seen on histopathological examination

Bottlenose dolphins ( Tursiops truncatus ) do also cast neutrophil extracellular traps against the apicomplexan parasite Neospora caninum

Neutrophil extracellular traps (NETs) are web-like structures composed of nuclear DNA decorated with histones and cytoplasmic peptides which antiparasitic properties have not previously been investigated in cetaceans. Polymorphonuclear neutrophils (PMN) were isolated from healthy bottlenose dolphins (Tursiops truncatus), and stimulated with Neospora caninum tachyzoites and the NETs-agonist zymosan. In vitro interactions of PMN with the tachyzoites resulted in rapid extrusion of NETs. For the demonstration and quantification of cetacean NETs, extracellular DNA was stained by using either Sytox Orange® or Pico Green®. Scanning electron microscopy (SEM) and fluorescence analyses demonstrated PMN-derived release of NETs upon exposure to tachyzoites of N. caninum. Co-localization studies of N. caninum induced cetacean NETs proved the presence of DNA adorned with histones (H1, H2A/H2B, H3, H4), neutrophil elastase (NE), myeloperoxidase (MPO) and pentraxin (PTX) confirming the molecular properties of mammalian NETosis. Dolphin-derived N. caninum-NETosis were efficiently suppressed by DNase I and diphenyleneiodonium (DPI) treatments. Our results indicate that cetacean-derived NETs represent an ancient, conserved and relevant defense effector mechanism of the host innate immune system against N. caninum and probably other related neozoan parasites circulating in the marine environment.

Influence of adult Anguillicoloides crassus load in European eels swimbladder on macrophage response

Anguillicoloides crassus has become one of the most important threats to the European eel (Anguilla anguilla). Adult parasites colonize the swimbladder leading to an impaired functioning of this organ. The infection is also responsible for an increased in the stress level of infected eels, that could produce an altered immune response as well. Differences in parasite loads and effects in the European and Japanese eel (Anguilla japonica) have been described. We have studied the influence of the number of adult parasites present in the swimbladder of wild eels on the macrophage response (phagocytosis and respiratory burst) as part of the first immune response to pathogens. Our results show an increased phagocytozed bacterial survival 24 h post-infection in macrophages of eels infected with more than ten adult parasites compared to macrophages from eels infected with less than those ten adult parasites. Respiratory burst results also showed a less efficient response in macrophages from eels infected with more than ten adult parasites, although in this case results were not found to be significant.

Associated risk factors influencing ovine Eimeria infections in southern Spain

Eimeria infections are common in sheep industry worldwide nonetheless very little is known on infection dynamics and associated risk factors influencing the outcome of clinical ovine coccidiosis. The aim of the present work was to analyse intrinsic (e. g. host age) and extrinsic (flock size, farm size and animal density) risk factors influencing dynamics of Eimeria spp. infections in sheep farms of the semi-arid region of Murcia in southern Spain. Overall, 64 ovine flocks in Murcia were surveyed and a total of 396 faecal samples were collected between May and July 2015. Flotation and McMaster techniques were performed for parasitological investigation. Excreted oocysts were identified on the basis of morphological as well as morphometric characteristics. In all analysed samples Eimeria spp. oocysts (100%) were found and 11 different Eimeria species were identified. Most prevalent species was E. ovinoidalis (97%) followed by E. parva/E.pallida (97%), E. weybridgensis (90.9%) and E. crandallis (89.4%), respectively. Concomitant infections with more than one Eimeria species were observed in all analysed samples. Analysis of intrinsic/extrinsic risk factor revealed age, herd/farm size and animal density to be the main factors significantly influencing Eimeria oocysts per gram of faeces counts (OPG) and overall prevalence of Eimeria spp. infections in sheep.