Assessing DESS solution for the long-term preservation of nematodes from faecal samples.

Preservation of biological samples is a relevant issue for many scientific disciplines. Although traditional preservers, such as formaldehyde or ethanol, imply major disadvantages related to health risks, DNA degradation and distortion of structures, they are widely used. Hence, the search for viable alternatives preserving morphometry and genetics seems necessary. Here we assess the suitability of DESS solution to preserve adult nematodes and their eggs in faeces. Concretely, faecal samples of terrestrial tortoises with oxyurids were used to: (i) compare the 1-month storage efficacy of eggs from different conservation protocols (faeces without preserver at -20 °C, faeces with DESS solution at room temperature, faeces with DESS solution at -20 °C and faeces with ethanol 70% at room temperature); (ii) address morphological nematode identification after 2 years of storage with DESS. We also corroborated that nematode DNA remained viable after 2 years. Overall, our results showed that DESS solution at room temperature is an advisable alternative to conserve both parasite eggs and adult nematodes for morphological identification and genetic purposes. It also offers the advantages of being low-cost, safe and suitable for fieldwork conditions and shipments without refrigeration for nematode preservation.

Density assessment and reporting for Phlebotomus perniciosus and other sand fly species in periurban residential estates in Spain.

Green periurban residential areas in Mediterranean countries have flourished in the last decades and become foci for leishmaniasis. To remedy the absence of information on vector ecology in these environments, we examined phlebotomine sand fly distribution in 29 sites in Murcia City over a 3-year period, including the plots of 20 detached houses and nine non-urbanized sites nearby. We collected 5,066 specimens from five species using "sticky" interception and light attraction traps. The relative frequency of the main Leishmania infantum vector Phlebotomus perniciosus in these traps was 32% and 63%, respectively. Sand fly density was widely variable spatially and temporally and greatest in non-urbanized sites, particularly in caves and abandoned buildings close to domestic animal holdings. Phlebotomus perniciosus density in house plots was positively correlated with those in non-urbanized sites, greatest in larger properties with extensive vegetation and non-permanently lived, but not associated to dog presence or a history of canine leishmaniasis. Within house plots, sand fly density was highest in traps closest to walls. Furthermore, the study provides a guideline for insect density assessment and reporting and is envisioned as a building block towards the development of a pan-European database for robust investigation of environmental determinants of sand fly distribution.

Evaluation of the Baermann-Wetzel method for detecting lungworm larvae in wild ruminants from faecal samples.

Lungworms can exert a negative impact on wild ruminant fitness; for this reason, the diagnosis of the associated diseases is an important prevention measure. The Baerman-Wetzel technique is the most usual method for the diagnosis of bronchopulmonary nematodes and is based on the active migration and movement of their first-stage larvae. Pulmonary tissue samples are frequently used for the post-mortem diagnosis of these parasites, but this kind of sample is not always available and easy to obtain. Faecal samples represent a more accessible choice for parasite monitoring. This work aimed to evaluate the agreement between the results obtained by the Baermann-Wetzel technique when samples of lung parenchyma or faeces from wild ruminants are used. A good level of agreement as well as a similar sensitivity between the two types of sample were observed, validating the use of faecal samples as a less invasive and cost-effective alternative for the monitoring of lungworm in wild ruminant populations.

Nasopharyngeal bot flies in red deer (Cervus elaphus) from southern Spain.

The nasopharyngeal bot flies Pharyngomyia picta and Cephenemyia auribarbis (Diptera: Oestridae) are parasites that have an impact on the health of wild ruminants. Little is known about their biological and epidemiological characteristics in multi-host habitats such as the Sierra de Cazorla, Segura y Las Villas Natural Park (CNP), in south-east Spain. This paper describes the main epidemiological features of bot fly larvae parasitising the population of red deer in CNP during 2003-2005. The results reveal an overall bot fly prevalence of 37.5%, with a P. picta and C. auribarbis co-infection rate of 12.5%. Although the statistical analyses were not significant(p > 0.05), a higher prevalence in males and in calves was observed, which has to be explained from a multifactorial viewpoint. Unfavourable climatic conditions during January induced the overwintering of larvae inside the host and, accordingly, a higher prevalence of the first instar (L1) was detected, while a higher prevalence of L2 and L3 was recorded in February and March. Further studies are needed to investigate in more detail the environmental characteristics that influence the chronobiology of bot flies in south-east Spain.

Les mouches nasopharyngées Pharyngomyia picta et Cephenemyia auribarbis (Diptera : Oestridae) sont des parasites qui affectent la santé des ruminants sauvages. Leurs caractéristiques biologiques et épidémiologiques au sein d'habitats tels que le Parc naturel des Sierras de Cazorla, Segura y las Villas (CNP) dans le sud-est de l'Espagne, où cohabitent de nombreuses espèces hôtes, sont mal connues. Les auteurs présentent les résultats d'une étude conduite de 2003 à 2005 visant à décrire les principales caractéristiques épidémiologiques de l'infestation par des larves de mouches dans les populations de cerfs élaphes du CNP. D'après les résultats de l'étude, la prévalence globale des mouches s'élève à 37,5 % avec un taux de co-infestation par P. picta et C. auribarbis atteignant 12,5 %. Bien que les analyses statistiques n'aient pas donné de résultats significatifs (p < 0,05), une prévalence plus élevée a été observée chez les mâles et les chevreuils, phénomène qui doit être expliqué dans une perspective multifactorielle. Les conditions climatiques défavorables durant le mois de janvier ont prolongé l'hivernage des larves au sein de l'hôte, ce qui s'est traduit par une prévalence plus élevée du premier stade larvaire (L1), tandis qu'en février et en mars les stades L2 et L3 étaient les plus fréquents. Des études complémentaires devront être menées afin d'élucider plus en détail les facteurs environnementaux susceptibles d'influer sur la chronobiologie de ces mouches dans le sud-est de l'Espagne.

Las moscas causantes de miasis nasofaríngea Pharyngomyia picta y Cephenemyia auribarbis (orden Diptera, familia Oestridae) son parásitos perjudiciales para la salud de los rumiantes salvajes. Poco se sabe acerca de sus características biológicas y epidemiológicas en hábitats donde hay múltiples hospedadores, como es el caso del Parque Natural de las Sierras de Cazorla, Segura y Las Villas (CNP), situado en el sudeste de España. Los autores describen las principales características epidemiológicas que afectan a las larvas de moscas de la miasis que parasitan a la población de ciervos del CNP según un estudio realizado desde 2003 hasta 2005. Los resultados revelan una prevalencia global de estas moscas del 37,5%, con una tasa de coinfección por P. picta y C. auribarbis del 12,5%. Aunque los análisis estadísticos no arrojaron un resultado significativo (p > 0,05), se observó una prevalencia superior en machos y ciervos jóvenes, hecho que debe explicarse desde una perspectiva multifactorial. Las desfavorables condiciones climáticas predominantes en enero propiciaron la diapausa invernal de las larvas en los hospedadores, lo que a su vez explica que se detectase una mayor prevalencia de larvas de primer estadio (L1), mientras que en febrero y marzo se registró una mayor prevalencia de larvas de segundo y tercer estadio (L2 y L3). Se requieren más investigaciones para estudiar con mayor detalle las características ambientales que influyen en la cronobiología de las moscas causantes de miasis en el sudeste de España.

Plastinated macroparasites, an alternative resource for use in practical lessons.

The plastination technique is a recently developed option to preserve biological tissues widely used in human and veterinary anatomy. This process allows one to obtain real, safe, clean, dry, resistant and permanently stable material without any additional treatment or maintenance. All these advantages are associated with the rapid expansion of plastination during recent decades in a high number of educational institutions. However, the studies of parasite conservation through plastination are scarce, although the material obtained has a high quality, as prior references have shown. In this study, 141 students of veterinary medicine and pharmacy university degrees used, in a blind study, plastinated specimens (experimental group) or wet specimens (control group) during three consecutive practical sessions. Afterwards all the students completed anonymous questionnaires on both knowledge and satisfaction. The results demonstrated that plastinated parasites are a valid and satisfactory alternative to be used as a teaching/learning tool during practical lessons. Moreover, with regard to the knowledge of morphological structures, the results from the questionnaire of assimilated knowledge showed no differences between the use of plastinated and formaldehyde-preserved parasites.

La technique de plastination est une méthode assez récente de préservation des tissus biologiques qui est désormais largement utilisée en anatomie humaine et vétérinaire. Ce procédé permet d'obtenir des préparations anatomiques réalistes, sûres, sèches, résistantes et stables qui ne nécessiteront pas de traitement ni d'entretien ultérieurs pour préserver leur durabilité. Ces avantages expliquent que le recours à la plastination se soit rapidement développé au cours des dernières décennies dans nombre d'institutions d'enseignement. Néanmoins, rares sont les études portant sur la préservation des parasites par plastination, bien que les spécimens obtenus lors de travaux antérieurs aient été jugés de très bonne qualité. Les auteurs présentent les résultats d'une enquête menée auprès de 141 étudiants préparant leur diplôme de médecine vétérinaire ou de pharmacie, à qui ont été distribués en aveugle des spécimens plastinés (groupe expérimental) et des spécimens conservés dans une solution liquide (groupe de contrôle) lors de trois séances consécutives de travaux pratiques. Il a ensuite été demandé aux étudiants de remplir anonymement un questionnaire portant sur les connaissances acquises lors de ces séances et sur leur degré de satisfaction. Les résultats ont montré que les parasites plastinés constituent une alternative valable et satisfaisante en tant que matériel pédagogique et d'entraînement pendant les leçons pratiques. Par ailleurs, s'agissant de l'étude des structures morphologiques, les résultats du questionnaire sur les connaissances acquises lors des travaux pratiques n'ont pas fait apparaître de différences entre les étudiants ayant travaillé sur des parasites plastinés et ceux ayant travaillé avec des parasites conservés dans le formol.

La técnica de la plastinación es un método de reciente aparición para conservar tejidos biológicos, utilizado con gran frecuencia en anatomía humana y veterinaria. Se trata de un proceso que permite obtener material real, inocuo, limpio, seco, resistente y con una estabilidad permanente sin necesidad de ninguna otra operación de tratamiento o mantenimiento. Todas estas ventajas explican que en los últimos decenios la técnica se haya extendido con rapidez por muy numerosas instituciones de enseñanza. Aun así, hay escasos estudios sobre la conservación de parásitos por plastinación, pese a que el material obtenido, como se desprende de referencias anteriores, es de gran calidad. Los autores describen un estudio ciego en el que 141 estudiantes universitarios en farmacia y medicina veterinaria emplearon muestras plastinadas (grupo experimental) o muestras húmedas (grupo de control) en tres clases prácticas consecutivas, tras lo cual todos los estudiantes respondieron anónimamente a un cuestionario que evaluaba tanto sus conocimientos como su nivel de satisfacción. Los resultados demostraron que los parásitos plastinados constituyen una alternativa válida y satisfactoria como herramienta para impartir y/o recibir clases prácticas. Además, desde el punto de vista del conocimiento de estructuras morfológicas, los resultados del cuestionario sobre conocimientos asimilados no pusieron de manifiesto diferencia alguna entre el uso de parásitos plastinados y el de parásitos conservados en formaldehído .

High prevalence and intensity of Stephanurus dentatus in a population of wild boar (Sus scrofa) in south western Spain.

In the period from October 2016 to February 2017, the urinary tracts of 390 wild boar (Sus scrofa) from four areas of south central Spain (102 from Doñana National Park; 150 from Sierra Morena and the Toledo Mountains; 84 from Sierra Nevada; 54 from Sierra de Cazorla, Segura y Las Villas Natural Park) were examined for the presence of adult specimens of Stephanurus dentatus (Nematoda: Strongyloidea). This parasite was only detected in the wild boar population of Doñana National Park, with high prevalence (76.5±4.2%; 78/102), mean intensity (43.2±4.4) and mean abundance (33.1±3.8). Juvenile wild boar had significantly lower prevalence and abundance than subadult and adult wild boar. The intensity of infestation was significantly higher in male than in female wild boar. The detection of a focus of S. dentatus infestation in the wild boar population in Doñana National Park will provide further opportunities for understanding the epidemiology of this parasite.

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.

Parasite prevalence in Mycobacterium spp. infected dairy goats in the region of Murcia (south-east Spain).

Eighty-four Murciano-Granadina dairy goats slaughtered in the region of Murcia (South-East Spain) were necropsied to evaluate parasitic infections. The majority of the animals (94.0%) were parasitised and multiple infections were present. Twenty-one parasite species were found, including 18 nematode species (Muellerius capillaris, Dictyocaulus filaria, Neostrongylus linearis, Cystocaulus ocreatus, Teladorsagia circumcincta, T. occidentalis, T. trifurcata, Marshallagia marshalli, Camelostrongylus mentulatus, Trichostrongylus capricola, Nematodirus abnormalis, N. filicollis, N. spathiger, T. vitrinus, T. colubriformis, Trichuris spp., Chabertia ovina and Skrjabinema ovis); one trematode species (Dicrocoelium dendriticum); one arthropod species (Oestrus ovis); and one protozoa genus (Eimeria spp.). Additionally, 17.85% of the animals were Mycobacterium spp. positive. Therefore, comparison between parasite prevalence, intensity and abundance in tuberculosis-positive and -negative animals was performed. Statistically significant differences between the prevalence of lungworms and gastrointestinal nematodes in Mycobacterium spp. infected and free goats were found. The paper discusses this co-infection between Mycobacteriaceae and endoparasites.

Une étude a été conduite sur 84 chèvres laitières de race Murciano­Granadina abattues dans la région de Murcia (sud-est de l'Espagne) afin d'évaluer la présence d'infections parasitaires. Dans leur grande majorité (94,0 %), les chèvres étaient infestées de parasites et le nombre de pluri-infections était important. Au total, 21 espèces de parasites ont été observées, dont 18 espèces de nématodes (Muellerius capillaris, Dictyocaulus filaria, Neostrongylus linearis, Cystocaulus ocreatus, Teladorsagia circumcincta, T. occidentalis, T. trifurcata, Marshallagia marshalli, Camelostrongylus mentulatus, Trichostrongylus capricola, Nematodirus abnormalis, N. filicollis, N. spathiger, T. vitrinus, T. colubriformis, Trichuris spp., Chabertia ovina et Skrjabinema ovis), une espèce de trématode (Dicrocoelium dendriticum), une espèce d'arthropode (Oestrus ovis) et des membres d'un genre de protozoaire (Eimeria spp.). En outre, la présence de Mycobacterium spp. a été détectée chez 17,85 % des chèvres examinées. Par conséquent, une étude comparative a été réalisée pour déterminer la prévalence, l'intensité et l'abondance des parasites chez les animaux ayant donné des résultats respectivement positifs et négatifs à la détection de la tuberculose. Des différences significatives au plan statistique ont été constatées entre les chèvres infectées et indemnes de Mycobacterium spp., respectivement, pour ce qui concerne la prévalence des vers pulmonaires et des nématodes gastro-intestinaux. Les auteurs font le point sur cette co-infection par des mycobactéries et des endoparasites.

Tras ser sacrificadas, ochenta y cuatro cabras lecheras murciano­granadinas de la región de Murcia (sudeste de España) fueron sometidas a necropsia para determinar la presencia de eventuales parasitosis. La mayoría de los animales (un 94,0%) presentaban parásitos y múltiples infecciones. Se descubrieron veintiuna especies de parásito: 18 especies de nemátodo (Muellerius capillaris, Dictyocaulus filaria, Neostrongylus linearis, Cystocaulus ocreatus, Teladorsagia circumcincta, T. occidentalis, T. trifurcata, Marshallagia marshalli, Camelostrongylus mentulatus, Trichostrongylus capricola, Nematodirus abnormalis, N. filicollis, N. spathiger, T. vitrinus, T. colubriformis, Trichuris spp., Chabertia ovina y Skrjabinema ovis); una especie de tremátodo (Dicrocoelium dendriticum); una especie de artrópodo (Oestrus ovis) y un género de protozoo (Eimeria spp.). Además, el 17,85% de los ejemplares eran positivos para Mycobacterium spp. A partir de ahí se procedió a comparar la prevalencia, intensidad y abundancia de parásitos en los animales positivos para la tuberculosis con respecto a los negativos. Se observaron diferencias estadísticamente significativas entre las cabras que estaban infectadas por Mycobacterium spp. y las que no lo estaban en cuanto a la prevalencia de nemátodos pulmonares y gastrointestinales. Los autores examinan esta infección concomitante entre micobacteriáceas y endoparásitos.

Richness and diversity of helminth species in eels from a hypersaline coastal lagoon, Mar Menor, south-east Spain.

The composition and diversity of parasite communities and intestinal components, as well as infra-community structure, were assessed in eels Anguilla anguilla, from Mar Menor, a permanent Mediterranean hypersaline coastal lagoon. Data were used to determine whether this helminth community differs in composition and structure from that of eels in lagoons with lower salinity regimes and higher freshwater inputs. A total prevalence of 93% was detected. Specifically, parasites were identified as Deropristis inflata, Bucephalus anguillae, Contracaecum sp., Anguillicoloides crassus and two plerocercoid larvae belonging to the order Proteocephalidae, the marine species representing 91% of the isolated helminths. In the total community, digenetic trematodes were the dominant group of helminths, and D. inflata, an eel specialist, dominated both the component community and the infra-community. Richness and diversity were low but similar to those reported in other saline lagoons, and maximum species per eel did not exceed four. At the infra-community level, higher abundance than in other brackish or marine Mediterranean environments was detected. The findings provide further evidence of the similarity in composition and structure of helminth communities in eels from various Mediterranean coastal lagoons. Moreover, salinity-dependent specificities are well supported and reflect the life history of individual eels.

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.

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 fattener's herds and 3-82% in other fattener's 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 herd's parasite load and reduce the use of acaridal drugs.

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 > or =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.

Recombinant vaccine for canine parvovirus in dogs.

VP2 is the major component of canine parvovirus (CPV) capsids. The VP2-coding gene was engineered to be expressed by a recombinant baculovirus under the control of the polyhedrin promoter. A transfer vector that contains the lacZ gene under the control of the p10 promoter was used in order to facilitate the selection of recombinants. The expressed VP2 was found to be structurally and immunologically indistinguishable from authentic VP2. The recombinant VP2 shows also the capability to self-assemble, forming viruslike particles similar in size and appearance to CPV virions. These viruslike particles have been used to immunize dogs in different doses and combinations of adjuvants, and the anti-CPV responses have been measured by enzyme-linked immunosorbent assay, monolayer protection assays, and an assay for the inhibition of hemagglutination. A dose of ca. 10 micrograms of VP2 was able to elicit a good protective response, higher than that obtained with a commercially available, inactivated vaccine. The results indicate that these viruslike particles can be used to protect dogs from CPV infection.