Prevalencia y desarrollo larvario de Cephenemyia spp. en corzos del norte de España

Traballo Fin de Grao en Veterinaria. Curso 2019/2020Cephenemyia spp. (Diptera: Oestridae) es la causante de una miasis nasofaríngea obligatoria y específica del corzo que se encuentra ampliamente extendida en el continente europeo donde ha sido descrita desde el pasado siglo y que en las dos últimas décadas está adquiriendo relevancia en España. Se ha llevado a cabo un estudio con un total de 37 corzos fallecidos por distintas causas en el norte de España entre los años 2018 y 2020. Para visualizar las larvas del díptero se abrió longitudinalmente la cabeza de los corzos y se examinó la tráquea, faringe, laringe, sacos retrofaríngeos, cavidad oral y nasal. Una vez identificadas las larvas, se comprobó que todas eran C. stimulator. Para el análisis de los resultados se consideraron diferentes factores intrínsecos y extrínsecos. La prevalencia de infestación por C. stimulator fue del 43,2%, con una intensidad media de 16,9±22,47 larvas/animal. En total se obtuvieron 271 larvas que se localizaron sobre todo en los cornetes nasales (46,9%) y en los sacos retrofaríngeos (35,8%) y, en menor proporción, en la glotis (14,7%), la boca (1,5%) y la tráquea (1,1%). La edad y el sexo de los animales influyeron de forma significativa en la prevalencia de esta miasis, así los animales adultos (55,5%) presentan 11,7 veces más riesgo de padecer una miasis por C. stimulator que los jóvenes (0%), probablemente debido a que, estos últimos al pasar más tiempo ocultos entre la vegetación están menos expuestos a las moscas de Cephenemyia. La prevalencia en los machos (60%) fue superior que en las hembras (23,5%); el comportamiento de defensa territorial al que se ven obligados los primeros los expone más a la actividad de las moscas, de modo que el riesgo de verse infestados por Cephenemyia es 4,65 veces superior al de las hembras. En las condiciones del estudio se observó que tanto el clima, como la causa de la muerte no influyeron de forma significativa en la prevalencia de esta miasis. La clasificación de las larvas según su estadio de desarrollo reveló que la mayoría eran larvas 3 (59%), seguidas por larvas 2 (39%) y larvas 1 (2%). La prevalencia por larvas de C. stimulator fue más elevada durante la primavera (64,3%) que en invierno (30%) y otoño (0%), siendo la primavera la única estación en la que se hallaron los 3 estadios larvarios; la mayor prevalencia observada en esta estación se debe a que en esta época pueden coexistir en un mismo animal larvas procedentes de distintas temporadas. En la actualidad, la infestación por C. stimulator es una miasis prevalente en el norte de España y que, por su difícil control y repercusiones negativas sobre la salud de los corzos, podría suponer un serio problema para las poblaciones de este ungulado silvestre.Cephenemyia spp. (Diptera: Oestridae) é a causante dunha miase nasofarínxea obrigatoria e específica do corzo que se atopa amplamente estendida no continente europeo onde está a ser descrita dende o pasado século e que nas dúas últimas décadas está adquirindo relevancia en España. Levouse a cabo un estudo cun total de 37 corzos falecidos por distintas causas no norte de España entre os anos 2018 e 2020. Para visualizar as larvas do díptero abriuse lonxitudinalmente a cabeza dos corzos e examinouse a traquea, farinxe, larinxe, sacos retrofarínxeos, cavidade oral e nasal. Unha vez identificadas as larvas, comprobouse que todas eran C. stimulator. Para a análise dos resultados consideráronse diferentes factores intrínsecos e extrínsecos. A prevalencia de infestación por C. stimulator foi do 43,2%, cunha intensidade media de 16,9±22,47 larvas/animal. En total obtivéronse 271 larvas que se localizaron sobre todo nos cornetes nasais (46,9%) e nos sacos retrofarínxeos (35,8%), e en menor proporción na glote (14,7%), boca (1,5%) e traquea (1,1%). A idade e o sexo dos animais influíron de forma significativa na prevalencia desta miase, así os animais adultos (55,5%) presentan 11,7 veces máis risco de padecer unha miase por C. stimulator que os novos (0%), probablemente debido a que, estes últimos ao pasar máis tempo ocultos entre a vexetación están menos expostos ás moscas de Cephenemyia. A prevalencia nos machos (60%) foi superior que nas femias (23,5%); o comportamento de defensa territorial ao que ven obrigados os primeiros exponos á actividade das moscas, de xeito que o risco de verse infestados por Cephenemyia é 4,65 veces superior ao das femias. Nas condicións do estudo observouse que tanto o clima, como a causa da morte non influíron de forma significativa na aparición desta miase. A clasificación das larvas segundo o seu estadio de desenvolvemento revelou que a meirande parte eran larvas 3 (59%), seguidas polas larvas 2 (39%) e larvas 1 (2%). A prevalencia por larvas de Cephenemyia foi máis elevada durante a primavera (64,3%) que en inverno (30%) e outono (0%), sendo a primavera a única estación na que se acharon os 3 estadios larvarios; a maior prevalencia observada nesta estación débese a que nesta época poden coexistir, nun mesmo animal, larvas procedentes de distintas tempadas. Na actualidade, a infestación por Cephenemyia é unha miase prevalente no norte de España e que, polo seu difícil control e repercusións negativas sobre a saúde dos corzos, podería supoñer un serio problema para as poboacións deste ungulado silvestre.Cephenemyia spp. (Diptera: Oestridae) is the cause of a nasopharyngeal myiasis, which is obligatory and specific to roe deer and is widely spread in Europe where it has been described since the last century and that in the last two decades is gaining relevance in Spain. A study has been carried out with a total of 37 roe deer that have died from different causes in the north of Spain between 2018 and 2020. To visualize the diptera larvae, the roe deer heads were opened lengthwise and the trachea, pharynx, larynx, retropharyngeal sacs, oral and nasal cavities were examined. Once the larvae were identified, they were found to be all C. stimulator. For the analysis of the results, different intrinsic and extrinsic factors were considered. The prevalence of C. stimulator infestation was 43,2%, with a mean intensity of 16,9±22,47 larvae/animal. A total of 271 larvae were obtained, mostly in the nasal turbinates (46,9%) and in the retropharyngeal sacs (35,8%) and, to a lesser extent, in the glottis (14,7%), the mouth (1,5%) and the trachea (1,1%). The age and sex of the animals significantly influenced the prevalence of this myiasis, so that adult animals (55,5%) have 11,7 times more risk of suffering from a C. stimulator myiasis than young animals (0%), probably because the latter spend more time hidden among vegetation and have less exposure to Cephenemyia flies. Prevalence in males (60%) was higher than in females (23,5%); the territorial defence behaviour of males exposed them to fly activity, so that the risk of being infested by Cephenemyia is 4,65 times higher than that of females. Under the conditions of the study, it was observed that climate and cause of death did not significantly influence the appearance of this myiais. The classification of the larvae according to their stage of development indicated that most of them were larvae 3 (59%), followed by larvae 2 (39%) and larvae 1 (2%). The prevalence of C. stimulator larvae was higher during spring (64,3%) than during winter (30%) and autumn (0%) months, spring being the only season when larvae belonging to the 3 stages were found; this higher prevalence in spring is due to the fact that larvae from different seasons can coexist in the same animal at this time. Nowadays, C. stimulator infestation is a well established myiasis in northern Spain and, due to its difficult control and negative repercussions on the health of the roe deer, could mean a serious problem for the populations of this wild ungulate

Cephenemyia stimulator (Diptera: Oestridae) myiasis in a roe deer (Capreolus capreolus) from Portugal

Herein we present a nasopharyngeal myiasis case by Cephenemyia stimulator in a roe deer hunted in Trás-os-Montes (NE Portugal). Preliminary inspection showed one larva sorting through the nostrils and the examination of the nasopharyngeal cavity showed more than 15 larvae in the glottis and retropharyngeal recesses. Four larvae were collected and stored into 70% ethanol for morphological and molecular identification. Three of the larvae were identified as third instars and the other one as a prepupa of Cephenemyia stimulator, being the first confirmation of this species in roe deer from Portugal. C. stimulator is currently widely distributed in roe deer from central and northern Spain so, the transboundary natural dispersal of these cervids would explain the introduction of this myiasis in Portugal. Further studies are needed to monitor the spreading of this infection in the westernmost populations of European roe deerThe authors are very grateful to Jorge Afonso (Carramo Safaris, Macedo de Cavaleiros, Portugal), the hunter who submitted the larvae for investigation. This work was supported by the projects UIDB7CVT700772/2020 and LA/P/0059/2020 funded by the Portuguese Foundation for Science and Technology (FCT) and by the Program for consolidating and structuring competitive research groups (ED4312019/04, Xunta de Galicia, Spain)S

Pedicle myiasis by Lucilia caesar (Diptera, Calliphoridae): an emerging disease in roe deer from north-western Spain

A total of 35 male roe deer (Capreolus capreolus) from Lugo province (north-western Spain) were examined for pedicle myiasis between 2020 and 2022. All these animals had died by different causes and were examined or preserved just after their death to avoid post-mortem infestations. After external and internal head inspection, five animals were diagnosed with severe myiasis at the basis of the antlers (14.29%; 95% confidence interval = 5.38–31.04). All the affected bucks presented a cutaneous wound (1.5–15 cm in diameter) around the pedicles with extensive tissue destruction, exposition of frontal and parietal bones, and massive infestation by dipteran larvae (2–12 mm long). Four of five roe deer showed whitish egg clusters adhered to the basis of the antlers. Moreover, in one animal, six larvae had penetrated the cranial cavity, and in two of them larvae were also found in the nasopharyngeal cavity. All the cases were recorded in summer (May–August). Morphological identification and subsequent molecular confirmation revealed that all animals were infested by different larval stages of Lucilia caesar (Diptera: Calliphoridae). This study represents the first report of pedicle myiasis in Spain. Since this disease is reported sporadically, the detection of five cases in a short period of time suggests an increase in the incidence of this myiasisS

The Goat as a Risk Factor for Parasitic Infections in Ovine Flocks

Small ruminants in northwestern Spain are frequently managed in mixed flocks. Sheep–goat joint management has not been considered a risk factor for parasite infection, so the main objective of this study was to establish if mixed management with goats supposes a risk factor for parasitic infections in ovine flocks. Two thousand and ninety-three sheep were sampled from 74 commercial meat ovine flocks for diagnostic of the main parasites. Goat contact was a risk factor for sheep to be infected by protostrongylids, Dictyocaulus filaria, gastrointestinal nematodes and Eimeria spp. In contrast, Moniezia, Fasciola hepatica, Dicrocoelium dendriticum and Paramphistomidae prevalences were not influenced. Sheep–goat mixed management can be considered as a risk factor, since goats would act as a source of pasture contamination for interspecific parasites (protostrongylids, Dictyocaulus filaria and gastrointestinal nematodes). In relation to host-specific parasites, such as Eimeria spp., goats cannot be considered as a source for sheep, but competition for food and spaces between both small ungulates can suppose a reduced grazing area to sheep, provoking high environmental contamination and stress that facilitate their infection. Future epidemiological studies for parasitic infections in small ruminants should consider sheep–goat mixed management as a possible risk factor to be included in multivariate analysesThis work was supported by a program for consolidating and structuring competitive research groups (ED431D 2019/04, Xunta de Galicia, Spain)S

Specificity of Stenurus (Metastrongyloidea: Pseudaliidae) infections in odontocetes stranded along the north-west Spanish coast

Parasites extracted from the lungs and the pterygoid sinus complex of 6 species of odontocetes stranded along the north-west Spanish coast (Northeast Atlantic) between 2009 and 2019 were morphologically identified. The samples belonged to 14 specimens, including 3 harbour porpoises, Phocoena phocoena, 6 short-finned pilot whales, Globicephala macrorhynchus, 1 long-finned pilot whale, Globicephala melas, 1 Risso's dolphin, Grampus griseus, 1 striped dolphin, Stenella coeruleoalba and 2 bottlenose dolphins, Tursiops truncatus. All animals (14/14) were infected by nematodes of the genus Stenurus spp.; moreover, two of them presented a mixed lung nematode infection by Stenurus spp. and Halocercus spp., and another two a mixed infection by Stenurus spp. and the trematode Nasitrema spp. in the pterygoid sinuses. The morphological characterization of the Stenurus specimens revealed the existence of three different species: Stenurus minor, present in the pterygoid sinuses of harbour porpoises with a mean intensity of 43.0 ± 9.0; Stenurus globicephalae, in the pterygoid sinuses of pilot whales and the Risso's dolphin (370.3 ± 579.4); and Stenurus ovatus infecting bottlenose and striped dolphins’ lungs (47.7 ± 76.5). This is the first citation of S. minor and S. ovatus in odontoceti from the Galician coast. Nematodes of the genus Stenurus are frequent in odontocetes stranded along the north-west Spanish coast. A clear host-parasite association was observed between S. minor and the Phocoenidae family, between S. globicephalae and the subfamily Globicephalinae and between S. ovatus and subfamily Delphininae. Different trophic position and niche segregation may lead to different patterns of specificityS

Cardiorespiratory nematodes and co-infections with gastrointestinal parasites in new arrivals at dog and cat shelters in north-western Spain

Metastrongyloid and trichuroid cardiorespiratory nematodes of dogs and cats are considered emergent in several European countries, and an increase in the number and extent of endemic foci has been described. Since data on their prevalence are limited in this continent, faecal samples from new arrivals (365 dogs and 65 cats) at two animal shelters in North-western Spain were analysed using both floatation and Baermann techniques. In order to confirm the microscopic identification of Metastrongylidae first stage larvae, molecular characterization based on the sequence of the ITS-2 was performed. The possible influence of some variables such as the species, sex and age of the animals and the co-infection with other gastrointestinal parasites on the prevalence of cardiorespiratory nematodes was analysed. The most prevalent metastrongylid was Aelurostrongylus abstrusus (15.4%) followed by Angiostrongylus vasorum (4.1%) and Crenosoma vulpis (1.1%). Regarding trichuroids, Eucoleus aerophilus and/or Eucoleus boehmi eggs were detected in 28 dogs (7.7%) and four cats (6.2%). Almost all animals positive to cardiorespiratory nematodes (86.8%) were co-infected with gastrointestinal parasites. The prevalence of Metastrongylidae and respiratory trichuroids was significantly higher in dogs co-infected with Taenia spp. and Toxocara canis or Giardia duodenalis and Sarcocystis spp., respectively. In cats, a significant higher prevalence of Metastrongylidae nematodes was found in animals co-infected with Toxocara cati. Our results reveal that cardiorespiratory nematodes are common in companion animals from north-western Spain, showing higher prevalences than those previously reported from this country. This investigation represents the first report of C. vulpis, E. aerophilus and E. boehmi in dogs from Spain. The identification of a number of zoonotic parasites is of public health concern. Our results indicate that these nematodes should be included in the differential diagnosis of dogs and cats from north-western Spain showing respiratory or cardiac clinical signsThis research was funded by the Program for consolidating and structuring competitive research groups (ED431C 2019/04, Xunta de Galicia, Spain)S

The Age-Related Cryptosporidium Species Distribution in Asymptomatic Cattle from North-Western Spain

An age-related distribution of Cryptosporidium species has been reported in cattle, with C. parvum being predominant in suckling calves, C. bovis and C. ryanae being predominant in post-weaned calves and C. andersoni being predominant in adults. However, variants to this pattern have recently been reported. Thus, fecal samples (n = 594) from asymptomatic cattle were collected in north-western Spain. Animals were classified as 2 years (G5). Cryptosporidium detection and species identification were performed by SSU rRNA PCR. Individual Cryptosporidium prevalence was 16.7%; it significantly decreased with age. Cryptosporidium parvum was predominant in G1 and C. bovis was predominant in the rest of the age classes; C. bovis and C. ryanae were especially prevalent in G2 and G3. Cryptosporidium occultus was not found in suckling calves. Finally, C. andersoni and C. xiaoi were occasionally detected in G5. The presence of C. parvum in all age classes implies significant animal and public health concerns. The predominance of C. bovis in cattle older than 1 month supports the idea that the age-related pattern of Cryptosporidium species described in cattle is not fully consistent, and thus further studies are still needed to identify those factors determining the species distributionThis research was funded by Ministerio de Ciencia e Innovación (Spain), grant number AGL2016-76034-P and by Xunta de Galicia (Spain), grant number 2017-PG117S

The Age-Related Cryptosporidium Species Distribution in Asymptomatic Cattle from North-Western Spain

An age-related distribution of Cryptosporidium species has been reported in cattle, with C. parvum being predominant in suckling calves, C. bovis and C. ryanae being predominant in post-weaned calves and C. andersoni being predominant in adults. However, variants to this pattern have recently been reported. Thus, fecal samples (n = 594) from asymptomatic cattle were collected in north-western Spain. Animals were classified as <1 month (G1), 1–2 months (G2), 2–12 months (G3), 12–24 months (G4) and >2 years (G5). Cryptosporidium detection and species identification were performed by SSU rRNA PCR. Individual Cryptosporidium prevalence was 16.7%; it significantly decreased with age. Cryptosporidium parvum was predominant in G1 and C. bovis was predominant in the rest of the age classes; C. bovis and C. ryanae were especially prevalent in G2 and G3. Cryptosporidium occultus was not found in suckling calves. Finally, C. andersoni and C. xiaoi were occasionally detected in G5. The presence of C. parvum in all age classes implies significant animal and public health concerns. The predominance of C. bovis in cattle older than 1 month supports the idea that the age-related pattern of Cryptosporidium species described in cattle is not fully consistent, and thus further studies are still needed to identify those factors determining the species distribution

The Age-Related <i>Cryptosporidium</i> Species Distribution in Asymptomatic Cattle from North-Western Spain

An age-related distribution of Cryptosporidium species has been reported in cattle, with C. parvum being predominant in suckling calves, C. bovis and C. ryanae being predominant in post-weaned calves and C. andersoni being predominant in adults. However, variants to this pattern have recently been reported. Thus, fecal samples (n = 594) from asymptomatic cattle were collected in north-western Spain. Animals were classified as 2 years (G5). Cryptosporidium detection and species identification were performed by SSU rRNA PCR. Individual Cryptosporidium prevalence was 16.7%; it significantly decreased with age. Cryptosporidium parvum was predominant in G1 and C. bovis was predominant in the rest of the age classes; C. bovis and C. ryanae were especially prevalent in G2 and G3. Cryptosporidium occultus was not found in suckling calves. Finally, C. andersoni and C. xiaoi were occasionally detected in G5. The presence of C. parvum in all age classes implies significant animal and public health concerns. The predominance of C. bovis in cattle older than 1 month supports the idea that the age-related pattern of Cryptosporidium species described in cattle is not fully consistent, and thus further studies are still needed to identify those factors determining the species distribution

Traumatic myiasis by Wohlfahrtia magnifica in sheep flocks from southeastern Spain: prevalence and risk factors

Wohlfahrtia magnifica (Diptera: Sarcophagidae) is an obligate myiasis-causing fly of livestock that is widely distributed throughout the Mediterranean basin. A total of 73 683 sheep from 122 flocks in Albacete Province (southeastern [SE] Spain) were examined to detect active traumatic myiasis. The influence of several individual and flock factors on the prevalence was also assessed. The overall flock prevalence of traumatic myiasis was 95.9%, with an individual prevalence of 7.1%. Wohlfahrtia magnifica was identified in all of the positive animals except one that was infested by Lucilia sericata (Diptera: Calliphoridae). Adults of both genders showed a higher risk of infestation than juveniles, whereas males of all ages displayed an increased risk of infestation than females of all ages; the existence of a lambing building on the farm, poor husbandry facilities and the location area were also identified as risk factors. Prevalence was highest in the summer, and the fly season lasted from March to November. Genitalia were the main location of infestation in males (94.4%) and females (76.3%). Our results reveal that traumatic myiasis by W. magnifica is widespread in southeastern Spain, hence preventive measures minimizing the attractiveness of sheep to gravid flies are necessary to avoid health and welfare problems and significant production losses in sheep flocksS