Assesment of Hypoderma infestation in a wild population of Cervus elaphus from mountains Atlantic ecosystems in southwestern Europe (Spain)

Hypodermosis in Cervus elaphus was studied in the Riaño Regional Hunting Reserve, Province of León, north-western Spain. One hundred and ten red deer were examined for the presence of warble fly larvae. They were analyzed by PCR analysis of the COI region of mt-DNA and identified as Hypoderma actaeon. The prevalence of larvae was 42.7% with a mean intensity of 12.5 ± 18 (range 1-80) warbles/deer infested. The distribution of larvae in the infested animals showed an aggregated/overdispersed pattern (aggregation index = 25.84), where the larvae are not randomly or uniformly distributed, but strongly aggregated among their hosts. Larvae were found in all three states. First and second-instars were observed mainly in the autumn until the end of winter (November-March) and third-instars in late winter until mid-spring (March-May). The adult animals and the males had a higher prevalence than the young and the females, finding statistically significant differences only according to the sex of the animals. Seasonal variations were observed in the prevalence with the highest number of infested animals in winter and autumn, but not in terms of the mean intensity of parasites. Additionally, we assessed the presence of anti-Hypoderma antibodies in serum by means of indirect ELISA tests, using a crude larval extract (CLE) and a purified fraction the hypodermin C (HyC) obtained from first instars of Spanish isolates of Hypoderma lineatum (cattle). These findings confirm that H. actaeon is widely distributed in northern Spain, and provide new information about its chronobiology in mountainous Atlantic ecosystems from southwestern Europe.

Evaluation of the efficacy of two postweaning colibacillosis vaccines in a field herd with PRRS circulation during postweaning stage

Postweaning diarrhea (PWD) and PRRS are two major concerns in swine production, which association has not been consistently explored. In the current scenario of restrictions in the use of antibiotics and ZnO, vaccination is more relevant to control PWD, but PRRS virus circulation may compromise the immune protection conferred by postweaning colibacillosis vaccines. We evaluated the efficacy of two postweaning colibacillosis vaccines (parenteral and oral) in a commercial herd affected by an outbreak of PWD and with PRRS circulation in postweaning. Five groups were studied during the postweaning period: one control (Group 1) and four vaccinated: two with each postweaning colibacillosis vaccine administered alone (Groups 2 and 3) or with sow vaccination against PRRS (Groups 4 and 5). We evaluated the effects on piglet weight, average daily weight gain and in the percentage of piglets with diarrhea, its duration, lethality and mortality. PRRS viremia and anti-PRRS antibodies were evaluated by qPCR and ELISA. Regarding control group, colibacillosis vaccination generally improved most of the measured parameters; but significant improvements were only observed in Groups 4 and 5 (p < 0.05). Moreover, cases of diarrhea occurred at different ages: in Groups 2 and 3 the peak of cases occurred just after ZnO was removed from the feed compared to Group 1, while in Groups 4 and 5 no peak was observed. This suggests that postweaning colibacillosis vaccination may be compromised by the PRRS circulation. In PRRS endemic herds an effective protection against PWD through vaccination may require PRRS vaccination to obtain a better performance.

Tick-borne pathogens in ticks from urban and suburban areas of north-western Spain: Importance of Ixodes frontalis harbouring zoonotic pathogens

To identify the questing tick populations in urban and suburban areas from the city of Lugo (NW Spain), ticks were collected monthly by flagging. The presence of Borrelia spp., Rickettsia spp. and Anaplasma phagocytophilum also was determined by polymerase chain reaction (PCR) and sequence analysis. Overall, 342 questing ticks were collected; the tick abundance was higher in suburban (95.9%) than in urban areas (4.1%). Ixodes frontalis was the most abundant (86.5%); 88.5% were larvae, 11.1% nymphs and 0.3% adults. All development stages of I. ricinus (7.3%) and adults of Rhipicephalus sanguineus sensu lato (5.8%) and Dermacentor reticulatus (0.3%) were found. Rickettsia spp. (31.9%) was more prevalent than Borrelia spp. (2.7%); no ticks were positive to A. phagocytophilum. Six Rickettsia species were identified (R. slovaca, R. monacensis, R. massiliae, R. raoultii, R. sibirica subsp. mongolitimonae and R. aeschielmanii); Candidatus Rickettsia rioja and two novel Rickettsia species also were detected. In addition, Borrelia turdi (1.8%) and B. valaisiana (0.9%) were identified in Ixodes ticks. This is the first report of R. slovaca in R. sanguineus s.l. and of R. monacensis, R. raoultii, R. slovaca, R. sibirica subsp. mongolitimonae and Ca. R. rioja in I. frontalis. Since most of the pathogens detected are zoonotic, their presence in these areas may have implications for public health.

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 myiasis.

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 deer.

A novel time-saving multiplex PCR assay for detecting and discriminating the most common canine Babesia species in Europe

In Europe, most cases of canine babesiosis are caused by Babesia canis, Babesia vogeli (large piroplasms) and Babesia vulpes (small piroplasm). Molecular diagnosis is recommended due to its high sensitivity. Species identification after sequencing allows applying a rapid and efficient treatment, leading to a better prognosis; however, it is expensive and time-consuming. Thus, the objective of the present study was to develop a time-saving multiplex polymerase chain reaction (PCR) for simultaneously detecting and discriminating between large and small forms without sequence analysis. A new multiplex PCR was designed and tested using blood samples from 79 dogs showing clinical signs compatible with babesiosis which were previously analysed using blood smears and molecular methods. Multiplex PCR successfully discriminated between both Babesia groups showing bands of 700 and 890 bp for B. canis/B. vogeli and B. vulpes, respectively. No significant differences in the results of both PCR were detected and a substantial agreement between protocols (κ = 0.64) was found. Our multiplex PCR represents a reliable tool for detecting infections by the major Babesia spp. in dogs from Europe. Since no sequence analysis is required for identifying the species involved, this PCR allows the rapid administration of an appropriate treatment, thus improving the survival rate of the infected animals. In addition, it will represent a helpful tool for unravelling the real prevalence and distribution of B. vulpes and its implication in clinical cases.

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 specificity.

•

Stenurus is the most prevalent lungworm in odontoceti.

•

First description of S. minor and S. ovatus in Galician waters.

•

Short-finned whales are the most intensely infected odontocetes.

•

Stenurus infection is favored by the greater length of the host.

•

Stenurus spp show a clear pattern of specificity with their hosts.

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 signs.

A case report of fatal feline babesiosis caused by Babesia canis in north western Spain

BACKGROUND

In Europe, Babesia infections in cats are sporadic and only partial knowledge is currently available since the number of described cases including both the clinical presentation and the molecular identification of the Babesia species involved is limited. In the present case report, the clinical signs, the epidemiological data and the molecular results suggest that this is the first reported fatal case of feline babesiosis caused by Babesia canis.

CASE PRESENTATION

A six month old female European shorthair cat from north-western Spain died after being hospitalized for two days. This animal was pregnant and showed anorexia, lethargy, weakness, jaundice and fever with increased respiratory and heart rates. Haematological analysis revealed haemolytic regenerative anaemia, thrombocytopenia and leukocytosis. The presence of piroplasms was assessed using a PCR targeting the 18S rRNA gene of Babesia spp. and Theileria spp.; the sample resulted positive and B. canis was identified by DNA sequence analysis. The possible existence of co-infections with other vector-borne pathogens such as Anaplasma spp., Bartonella spp., Borrelia burgdorferi s.l., Cytauxzoon spp., Ehrlichia spp., Hepatozoon canis, Mycoplasma spp. or Rickettsia spp. was excluded by qPCR.

CONCLUSIONS

Our results together with previous reports on Babesia infections in cats from Europe suggest that feline babesiosis should be included in the differential diagnosis of animals with anaemia, thrombocytopenia, anorexia and lethargy, especially in young or immunocompromised animals from endemic areas for canine babesiosis.

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 flocks.

Antimicrobial Susceptibility of Enterotoxigenic Escherichia coli from Diarrhoeic Neonatal Calves in Spain

Simple Summary

Neonatal calf diarrhoea, a worldwide concern for cattle production, can be caused by viral, bacterial and protozoan enteropathogens: the enterotoxigenic Escherichia coli (ETEC) is one of the most important. The use of antimicrobials for treating neonatal calf diarrhoea cases is still a common practice among veterinary surgeons, although its use is only justified in bacterial infections evolving towards a systemic disease. Since the indiscriminate use of antimicrobials for treating diarrhoeic calves increases the risk for the appearance of antimicrobial resistances, restrictions on the use of antimicrobials in veterinary practice were implemented. The aim of this study was to characterize the antimicrobial susceptibility of ETEC strains obtained from diarrhoeic calves. Our results are alarming since all ETEC strains were resistant to three or more families of antimicrobials; in addition, a high number of strains were resistant to most first-line antimicrobials used in veterinary practice. Only ceftiofur, cefoperazone, cefquinome and gentamicin presented efficacy against most ETEC strains. Thus, empirical treatment of calf scours caused by ETEC is usually ineffective. Our results reveal that performing antimicrobial susceptibility tests in each NCD outbreak is needed for establishing an effective treatment and avoiding the emergence of new resistance mechanisms.

Abstract

Enterotoxigenic Escherichia coli (ETEC) is one of the major pathogens involved in neonatal calf diarrhoea (NCD) causing high economic losses in dairy farms. Antibiotic treatment is common in cases of systemic illness caused by NCD, but antimicrobial susceptibility tests (AST) are usually not performed. Thus, the aim of this study was to characterize the antimicrobial susceptibility of ETEC strains obtained from calves with diarrhoea between 2018–2020. Faecal samples (n = 420) were analyzed to detect the typical ETEC virulence factors F5 and STa. Positive samples were cultured to identify and isolate ETEC strains (n = 41) and ASTs were performed. Our results are alarming since ETEC strains resistant to three or more families of antimicrobials were detected in all isolates. Only four antibiotics (ceftiofur, cefoperazone, cefquinome and gentamicin) presented efficacy against more than 90% of the ETEC strains, while the other ten antibiotics were effective against less than 40% of the strains. In addition, a high number of strains were resistant to most first-line antimicrobials used in veterinary practice. For this reason, when ETEC infection is suspected, an AST must always be performed to select the most appropriate antimicrobial in each case and to avoid the emergence of new resistance mechanisms.

Diversity of Anaplasma species and importance of mixed infections in roe deer from Spain

Although wildlife can act as reservoirs of some Anaplasma species, studies on the presence and distribution of Anaplasma spp. in wild cervids are mainly limited and focused on zoonotic species. In order to identify the Anaplasma species in roe deer from Spain and to detect co-infections, 224 spleen samples were tested for Anaplasma spp. using a commercial qPCR; positive samples were further characterized using generic 16S rRNA primers and species-specific primers targeting the msp2 and groEL genes. Anaplasma DNA was detected in the 50.9% of samples, and four Anaplasma species were identified. Anaplasma phagocytophilum (43.8%) was predominant, followed by Anaplasma bovis (13.8%), Anaplasma capra (5.8%) and Anaplasma ovis (2.2%). In addition, strains similar to Anaplasma platys were found in nine animals. Most positive roe deer (71.9%) were infected with a single Anaplasma species, whereas co-infections with two (19.3%) or three (8.8%) Anaplasma species were also found. This study confirms the widespread occurrence of Anaplasma spp. in roe deer from Spain, being the first report of A. platys-like strains and A. capra in this cervid; it is also the first report of A. capra in Spain. The detection of Anaplasma species pathogenic for humans and/or domestic animals in roe deer suggests that this cervid may play a role in the sylvatic cycle of these bacteria contributing to the appearance of clinical anaplasmosis cases. In addition, co-infections are common in roe deer revealing that Anaplasma species specific PCR assays are essential for a reliable identification as well as for determining their real prevalence.

Monitoring of porcine circovirus type 2 infection through air and surface samples in vaccinated and unvaccinated fattening farms

Air and surfaces of swine farms are the two alternative samples to obtain information about the health status of the herd. The aim of this study was to assess air and surface sampling for the detection of porcine circovirus type 2 (PCV2) in vaccinated and unvaccinated fattening farms, studying the relationship between the viral load in these samples with the viremia at herd level. Three swine fattening batches (one unvaccinated; two vaccinated) were monitored at 10, 12, 14, 16 and 18 weeks old; at each stage, blood, air and different surfaces were sampled and analysed by qPCR. In all herds, PCV2 was detected in all types of samples. Whenever viremia was detected, PCV2 was also detected in air and surface samples, even in those cases with a low estimated prevalence (1.6%); moreover, in two out of the three herds, PCV2 was detected in air and surface samples earlier than in the blood of the sampled population. In addition, a good correlation between the viremia of pig population and the PCV2 load in air and surface samples was found in both cases (τ = 0.672 and 0.746, respectively; p <0.05). These results show that air and surface samples could be useful tools to monitor PCV2 infection, being suitable for detecting the virus in cases of low prevalence and even before pigs develop viremia; therefore, these sampling techniques would speed up the implementation of the required measures to prevent productive and economic losses due to PCV2 infection.

Molecular detection and identification of piroplasms (Babesia spp. and Theileria spp.) and Anaplasma phagocytophilum in questing ticks from northwest Spain

Anaplasma phagocytophilum and some piroplasm species are pathogens mainly transmitted by Ixodes ricinus. Considering that this tick species is predominant in north-western Spain, individual specimens (652 nymphs, 202 females and 202 males) and 23 larval pools were processed to determine the prevalence of these pathogens in questing I. ricinus from that region. Additionally, Dermacentor marginatus, Dermacentor reticulatus, Ixodes frontalis and Ixodes acuminatus were individually analysed. The groESL operon as well as the 16S rRNA and msp2 genes of Anaplasma were analysed. Similarly, piroplasms were identified at the 18S rRNA gene and the ITS1 of Babesia spp. and Theileria spp. Babesia venatorum (1.5%), A. phagocytophilum (0.7%), Babesia microti (0.3%) and Theileria sp. OT3 (0.2%) were detected in I. ricinus. A single I. frontalis (8.3%) tested positive to A. phagocytophilum. Although a low percentage of I. ricinus were infected with A. phagocytophilum and piroplasms, a potentially human pathogenic variant of A. phagocytophilum was detected, and both Babesia species found were zoonotic. Since the vector of Theileria sp. OT3 remains unknown, further investigations are needed to unravel the role of I. ricinus in the transmission of this piroplasm.

Major differences in the larval anatomy of the digestive and excretory systems of three Oestridae species revealed by micro-CT

Oestrid flies (Diptera: Oestridae) do not feed during the adult stage, so they depend on an efficient assimilation and storage of nutrients during their parasitic larval stage. We describe the general morphology and provide volumetric data for the digestive and excretory organs of the three larval instars of the nasal bot fly Oestrus ovis L., using micro-computed tomography. The size of the digestive and excretory organs greatly increased across larval instars. In all instars, the two salivary glands were remarkably large and formed a 'glandular band' by coming together, but without lumina uniting, at their posterior ends. The distal region of the anterior Malpighian tubules was greatly enlarged and full of highly radio-opaque concretions. Moreover, the anatomy of O. ovis third-instar larva was compared to that of two species of, respectively, similar and different feeding habits: Cephenemyia stimulator (Clark) and Hypoderma actaeon Brauer. Whereas the general morphology and arrangement of the digestive and excretory systems of C. stimulator was similar to that of O. ovis, some differences were observed in H. actaeon: a swollen anterior region of the midgut, salivary glands shorter and not forming a 'band' and anterior Malpighian tubules narrowly uniform throughout their entire length.

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

Simple Summary

An age-related distribution of Cryptosporidium species has been reported in cattle, with the pathogenic and zoonotic 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. Unravelling the age-related species distribution pattern in cattle from a particular region will allow determining those age classes posing a higher risk to public and animal health. Thus, fecal samples from asymptomatic cattle were collected in north-western Spain. Cryptosporidium detection and species identification was performed by molecular methods. Cryptosporidium prevalence was 16.7%; it significantly decreased with age. Cryptosporidium andersoni, C. bovis, C. occultus, C. parvum, C. ryanae and C. xiaoi were identified. Cryptosporidium parvum was predominant in calves younger than 1 month and C. bovis was predominant in the rest of the age groups. The presence of C. parvum in all age groups implies 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 needed to identify those factors determining the species distribution.

Abstract

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.

Molecular epidemiology of Aleutian mink disease virus causing outbreaks in mink farms from Southwestern Europe: a retrospective study from 2012 to 2019

BACKGROUND

Aleutian mink disease virus (AMDV) causes major economic losses in fur-bearing animal production. The control of most AMDV outbreaks is complex due to the difficulties of establishing the source of infection based only on the available on-farm epidemiological data. In this sense, phylogenetic analysis of the strains present in a farm may help elucidate the origin of the infection and improve the control and biosecurity measures.

OBJECTIVES

This study had the following aims: characterize the AMDV strains from most outbreaks produced at Spanish farms between 2012-2019 at the molecular level, and assess the utility of the combined use of molecular and epidemiological data to track the possible routes of infection.

METHODS

Thirty-seven strains from 17 farms were partially sequenced for the NS1 and VP2 genes and analyzed phylogenetically with other strains described worldwide.

RESULTS

Spanish AMDV strains are clustered in four major clades that generally show a good geographical correlation, confirming that most had been established in Spain a long time ago. The combined study of phylogenetic results and epidemiological information of each farm suggests that most of the AMDV outbreaks since 2012 had been produced by within-farm reservoirs, while a few of them may have been due to the introduction of the virus through international trade.

CONCLUSIONS

The combination of phylogenetic inference, together with epidemiological data, helps assess the possible origin of AMDV infections in mink farms and improving the control and prevention of this disease.

Efficacy of Oxyclozanide and Closantel against Rumen Flukes (Paramphistomidae) in Naturally Infected Sheep

Simple Summary

Paramphistomosis, caused by ruminal trematodes, is currently considered an emergent disease in Europe due to the progressive increase of prevalence and reports of acute cases in ruminants. Thus, finding effective control methods such as efficient drugs against paramphistomids is currently a priority. Although some drugs have been found effective for treating paramphistomid infections in cattle, data in sheep are currently limited. A single administration of oxyclozanide (15 mg/kg) or closantel (10 mg/kg) has been proven efficient in cattle, but it has not been tested in sheep; thus, the aim of the present study was to assess the effectiveness of these treatment protocols against paramphistomids in naturally infected sheep. The treatment with oxyclozanide was very efficient since it significantly reduced the paramphistomid egg output in more than 90% during 11 weeks after treatment. In contrast, closantel showed low efficacies throughout the study. The results of this study support the use of a single oral dose of oxyclozanide at 15 mg/kg for treating paramphistomid infections in sheep, whereas a single oral dose of closantel at 10 mg/kg is not effective.

Abstract

Paramphistomosis is considered an emergent disease of ruminants in Europe. Some drugs have been found effective for treating paramphistomid infections in cattle, but data in sheep are currently limited. Thus, faecal samples from 25 adult sheep naturally infected with paramphistomids were collected weekly to test the efficacy of oxyclozanide and closantel. Three groups were performed: nine animals orally treated with a single dose of oxyclozanide (15 mg/kg bodyweight (BW) integrated the G-OXI group, whereas eight sheep orally treated with a single dose of closantel (10 mg/kg BW) were placed in a group called G-CLS. Eight untreated controls constituted the group G-CON. Oxyclozanide showed efficacies up to 90% until week 11 post-treatment, with a maximum efficacy of 98.3%, and significant differences were found between G-OXI and G-CON until the 26th week post-treatment. Closantel was insufficiently active (0–81%) throughout the study and differences compared to G-CON were never found. The present study reveals that oxyclozanide given at a single oral dose of 15 mg/kg BW is highly effective against adult rumen flukes in sheep. In addition, the use of a single oral dose of closantel at 10 mg/kg BW is not recommended for treating paramphistomid infections in sheep.

Epidemiological study of the association between bovine gammaherpesvirus type 4 and reproductive disease in dairy cattle from northwestern Spain

Bovine gammaherpesvirus 4 (BoHV-4) has controversially been related with cattle reproductive disease. In the present study we analyze the relationship between exposure to BoHV-4 and reproductive performance in dairy cattle from northwestern Spain. A total of 2022 sera from 50 farms were examined to detect anti-BoHV-4 antibodies. Herd and individual reproductive records were collected to analyze association with exposure to BoHV-4. In addition, 52 abortion cases were examined to detect BoHV-4 DNA. An individual seroprevalence of 66.6 % and a herd prevalence of 98 % were found. Exposure to BoHV-4 increased with age, particularly in individuals between 26-36 months old (OR = 2.7; CI 95 %: 1.2-5.0, compared to animals < 26 months). Seroprevalence was not associated with herd fertility and herd abortion rate, but seropositive animals between 26-36 months presented prolonged calving to fertilizing insemination intervals (HR: 1.4; CI 95 %: 1.2-2.0) as well as higher odds of an unsuccessful 1^st insemination (OR: 2.5; CI 95 %: 1.2-5.0). In abortion cases, BoHV-4 DNA was found in 12 vaginal swabs from 5 farms but not in any fetal tissue. Our results reveal an endemic, high and widespread exposure to BoHV-4 among dairy cattle from NW Spain with a limited impact in the reproductive performance of herds. The significantly worse reproductive performance of seropositive animals of 26-36 months of age may be the consequence of the establishment of primo-infections when moving heifers to lactation lots. Our findings may be useful to understand the potential population impact of BoHV-4.

Molecular detection of myxoma virus in the environment of vaccinated rabbitries

Myxoma virus (MYXV) is the aetiological agent of myxomatosis, a systemic, mostly lethal disease that affects European rabbits. Vaccination against it, although widespread, has not been completely effective and disease outbreaks still take place on farms which carry out vaccination programmes. Since some of these cases have been attributed to airborne transmission or the spread of the virus via inanimate vectors, the aims of this study were to determine MYXV contamination levels and distribution in the environment of vaccinated farms and to ascertain whether the detected virus corresponded to field strains. For that, environmental samples from several areas, tools and employees from four (three infected and one uninfected) rabbitries were taken and analysed by qPCR. MYXV was detected in the environment of all the infected farms, whereas all the samples from the non-infected farm were negative. Furthermore, all the positive samples contained viral DNA compatible with field strains of the virus. These results lead us to believe that the administration of currently available commercial vaccines does not prevent infected animals from shedding the field virus. Moreover, viral DNA was also found in items that are not in direct contact with the animals, which could play a role in the transmission of the infection throughout the farm and to other farms. Therefore, this study proves that current vaccination schemes on their own are not sufficient to prevent this disease and should be accompanied by adequate biosecurity measures.

Cytokine expression in bovine PBMC cultures stimulated with Hypoderma lineatum antigens

Hypoderma antigens are involved in host inflammation and immune response, conditioning larvae survival. In this study, peripheral blood mononuclear cell (PBMC) cultures from Hypoderma sensitized and unsensitized cattle were performed to determine the effect of H. lineatum antigens and incubation time (18, 24, 48 h) on IFN-γ, TNF-α, IL-10 and IL-4 mRNA gene expression determined by RT-qPCR. TNF-α and IL-4 gene expression were higher in Hypoderma previously sensitized PBMCs, suggesting that a mixed Th1/Th2 response may play a significant role in host defence reactions against Hypoderma exhibited by previously infested cattle. Incubation time had a significant effect on IL-10 and TNF-α gene expression, which decreased over time. Regarding to H. lineatum antigens, the crude larval extract and the purified fraction hypodermin B (HB) produced a significant reduction of the mRNA expression levels of the proinflammatory cytokine, IFN-γ; moreover, the HB had a stimulating effect on the mRNA gene expression of the anti-inflammatory cytokine IL-10, demonstrating that the parasite would modulate the host defence mechanisms by avoiding harmful immune responses that would limit its survival into the host tissues.

Temporal and spatial spread of Hypoderma actaeon infection in roe deer from peninsular Spain determined by an indirect enzyme-linked immunosorbent assay

The host switching of Hypoderma actaeon (Diptera: Oestridae), a specific parasite of red deer (Cervus elaphus), towards roe deer (Capreolus capreolus) has been recently reported in Spain. To provide information about the temporal and spatial spreading of H. actaeon infection in roe deer, 244 serum samples from animals hunted in Spain between 2013 and 2018 were analysed by an indirect enzyme-linked immunosorbent assay. The overall seropositivity was 13.9%. Seropositivity was higher in continental (27.7%) and mountainous (12%) areas from central Spain, followed by southern-Mediterranean (11.2%) and northern-oceanic regions (3.5%). Differences were significant between central-continental and northern-oceanic regions (P = 0.003). No differences were found according to the sex and age of roe deer (P > 0.05). In 2013, all seropositive animals were concentrated in two distant areas in central and southern Spain, suggesting that the host switch could have occurred independently in both regions. Changes in the pattern of distribution of red deer and roe deer could have favoured the spreading of this myiasis towards roe deer, indicating that roe deer may become infested by H. actaeon in areas where both cervids coexist at high densities.

Prevalence and molecular characterization of Anaplasma phagocytophilum in roe deer (Capreolus capreolus) from Spain

Anaplasma phagocytophilum can infect a wide range of vertebrates; nevertheless, some genetic variants are associated with particular species of tick vectors and animal hosts. It has been suggested that roe deer (Capreolus capreolus) mainly acts as a reservoir of several A. phagocytophilum non-pathogenic variants for other animal species. The aim of this study was to determine the prevalence and identify the genetic variants of A. phagocytophilum in roe deer from Spain in order to assess host-pathogen associations and their pathogenic potential. The spleens of 212 roe deer hunted in Spain were individually collected and analysed by a commercial qPCR kit in order to detect the presence of A. phagocytophilum DNA. Positive samples were further characterized at groESL, 16S rRNA and msp2 partial genes. The possible influence of several intrinsic (age and sex) and extrinsic factors (ecological area) on A. phagocytophilum prevalence was analysed using a logistic regression. Overall, 41.5 % of the samples resulted positive to A. phagocytophilum. The percentage of infected roe deer was significantly higher in the Mediterranean and Oceanic areas than in the Continental and Mountain regions; nevertheless, prevalence was not related to age or sex. Sequence analysis at groESL and 16S rRNA genes allowed the identification of three ecotypes (I to III) and four variants ("Y", "X", "W", "I"), respectively. A high percentage of roe deer from Spain is infected with different variants of A. phagocytophilum; these results have implications for public and animal health since some of these ecotypes and variants have been previously identified in both human and animal clinical cases.

Monitoring of the shedding and serological dynamics of Bovine gammaherpesvirus type 4 in a dairy cattle herd

Bovine gammaherpesvirus type 4 (BoHV-4) is increasingly related with reproductive disease in cattle, but its epidemiology is not fully understood. We monitored the serological response and shedding of BoHV-4 in a positive dairy cattle farm with metritis. First, we performed an ELISA to detect BoHV-4 antibodies in all the animals (n = 104). Afterwards, ten seronegative heifers introduced in the production lot and sera samples were monthly taken for four months and then 6-10 months after introduction to detect BoHV-4 antibodies by ELISA. Moreover, a vaginal swab was taken after calving to detect BoHV-4 by PCR. Concurrently, a weekly collection of vaginal and nasal swabs and milk was performed during the first month post-partum in multiparous cows with metritis (n = 14), heifers with metritis (n = 4), heifers without metritis but positive to BoHV-4 (ELISA or PCR) (n = 2) and multiparous cows without metritis (n = 3). Seropositivity was higher in older animals and in the production lot. Three heifers which shed BoHV-4 after parturition resulted seronegative at first but eventually seroconverted. In the same vein, most heifers seroconverted after 6-10 months in the production lot (8/10). Multiparous cows shed virus by various routes: 13/14 (93 %) in vaginal secretions, 7/14 (50 %) in nasal exudates and 7/14 (50 %) in milk. However, in the other groups, shedding was only detected in vaginal swabs from the first week post-partum. Our study describes BoHV-4 shedding in field conditions. Seronegative animals may become horizontally infected when moved to a contaminated environment.

Prevalence and molecular characterization of Rickettsia spp. in questing ticks from north-western Spain

Tick-borne rickettsioses, most of them belonging to the spotted fever group (SFG), have been recognized as important emerging vector-borne zoonotic diseases. In order to determine the presence of Rickettsia spp. in questing ticks from north-western Spain, 1056 Ixodes ricinus, 19 Dermacentor marginatus, 17 Dermacentor reticulatus and one Ixodes acuminatus were processed. Rickettsia DNA was detected by PCR targeting rOmpA and rOmpB genes. A total of 219 (20.7%) I. ricinus, 19 (100%) D. marginatus and four D. reticulatus (23.5%) were positive. The prevalence was significantly higher in I. ricinus from coastal areas and in winter. Five species were identified: Rickettsia felis, Rickettsia monacensis, Rickettsia raoultii, Rickettsia slovaca and "Candidatus Rickettsia rioja". Our results reveal a significant presence of some pathogenic Rickettsia species in questing tick populations from this area which involves a noticeable risk of rickettsiosis. As R. raoultii, R. slovaca and "Ca. R. rioja" DNA were identified in I. ricinus, considered an unusual vector for these Rickettsia species, further studies are needed to unravel the role of that tick species in the maintenance and transmission of these three Rickettsia species in north-western Spain.

Occurrence of Borrelia and Borreliella species in Ixodes ricinus collected from roe deer in northwestern Spain

Ixodes ricinus, comprising the predominant tick species in Europe, can transmit important human pathogens, including Borreliella spp., the causal agent of Lyme borreliosis. One hundred and seventy five roe deer hunted in two areas (plateau and mountain) of Galicia (northwest Spain) were examined for the presence of ticks; all roe deer were infested by I. ricinus. Nymphs (n = 1000), males (n = 1449) and females (n = 1000) of I. ricinus were analysed in pools of up to 10 ticks to detect both Borreliella and Borrelia DNA. The average number of I. ricinus per roe deer was similar in both areas, regardless of the life stage; although the percentage of Borreliella and Borrelia positive pools was higher in ticks collected from roe deer hunted in the plateau area, no significant differences were detected. Sequence analysis at the flagellin gene allowed the identification of four Borreliella species (Borreliella afzelii, Borreliella garinii, Borreliella lusitaniae and Borreliella valaisiana) and Borrelia miyamotoi in adult males; only B. valaisiana and B. miyamotoi were detected in nymphs and all females were negative. All Borreliella and Borrelia species found in roe deer were previously identified in questing I. ricinus collected in the same study area, although the prevalence was lower in the present study. The analysis of male I. ricinus ticks collected from roe deer gives a good estimation of Borreliella diversity in questing ticks.

Prevalence and distribution of Babesia and Theileria species in roe deer from Spain

Babesiosis and Theileriosis are important worldwide-distributed tick-borne diseases for human and animals. Their presence in a particular area depends on the presence of suitable tick-vector and host species as well as competent reservoirs such as roe deer, one of the most abundant wild cervids in Spain. Spleen samples from 174 roe deer hunted in Spain were analysed to determine the prevalence of Babesia and Theileria species. DNA of both piroplasms was firstly detected using a commercial qPCR. Then, positive samples were molecularly characterized at the 18S rRNA and ITS1 genes of Babesia spp. and Theileria spp. The possible influence of some factors such as ecological area, age and sex was also assessed. Overall, 89.7% of roe deer were positive to any of the two piroplasms. Theileria spp. was more prevalent (60.9%) than Babesia spp. (19.0%); species identification could not be achieved in 17.3% of positive samples. Babesia prevalence was significantly higher in young animals and in roe deer from Oceanic regions, in contrast to Theileria spp. Five species were identified: Theileria sp. OT3 (60.3%), Babesia capreoli (15.5%), Babesia venatorum (2.9%), Theileria sp. 3185/02 (0.6%) and Babesia bigemina (0.6%). The coinfection B. capreoli/T. sp. OT3 was the most common (4.6%) followed by B. venatorum/T. sp. OT3 (0.6%) and B. bigemina/T. sp. OT3 (0.6%). Our results reveal that Theileria spp. and Babesia spp. are prevalent piroplasms in roe deer from Spain. These cervids can act as reservoirs for several Babesia and Theileria species, including the zoonotic B. venatorum. This study represents the first description of B. venatorum and B. bigemina in roe deer from Spain.

Molecular identification of Borrelia spirochetes in questing Ixodes ricinus from northwestern Spain

BACKGROUND

Ixodes ricinus, the predominant tick species in Europe, can transmit the causative agents of important human diseases such as Lyme borreliosis (LB), caused by Borrelia spirochetes. In northern Spain, LB is considered endemic; recently, a significant increase of the annual incidence of LB was reported in the northwestern (NW) region.

METHODS

In order to provide information on the prevalence of Borrelia spp., pooled and individually free-living I. ricinus from NW Spain were molecularly analyzed. Positive samples were characterized at the fla and Glpq genes and the rrfA-rrlB intergenic spacer region to identify Borrelia species/genospecies.

RESULTS

Borrelia burgdorferi (sensu lato) (s.l.) individual prevalence and MIR were significantly higher in adult females (32.3 and 16%) than in nymphs (18.8 and 6.2%) and adult males (15.6 and 8.4%). Five Borrelia genospecies belonging to the B. burgdorferi (s.l.) group were identified: B. garinii was predominant, followed by B. valaisiana, B. lusitaniae, B. afzelii and B. burgdorferi (sensu stricto) (s.s.). One species belonging to the tick-borne relapsing fever group (B. miyamotoi) was also found, showing low individual prevalence (1%), positive pool (0.7%) and MIR (0.1%) values. To our knowledge, this is the first citation of B. miyamotoi in free-living ticks from Spain.

CONCLUSIONS

The significant prevalences of B. burgdorferi (s.l.) genospecies detected in questing ticks from NW Spain are similar to those detected in northern and central European countries and higher to those previously found in Spain. These results together with the high incidence of LB in humans and the high seroprevalence of B. burgdorferi (s.l.) in roe deer shown in other studies reveal that the northwest area is one of the most risky regions for acquiring LB in Spain.

Hypoderma actaeon: an emerging myiasis in roe deer (Capreolus capreolus)

Subcutaneous larvae of Hypoderma spp. (Diptera: Oestridae) were detected in the dorsal region in 10 roe deer, Capreolus capreolus (Artiodactyla: Cervidae), hunted in central Spain between January and March 2016. All larvae were found in the inner side of the hide during the skinning of the animals. The study of the morphological features of eight larvae of different stages collected from two animals allowed the identification of Hypoderma actaeon Brauer. The small size (4-5 mm) of some of the first instars suggests that the internal lifecycle of H. actaeon may be exclusively subcutaneous. This is the first confirmation of H. actaeon in roe deer; however, further studies to assess the spread of the parasite and to follow the evolution of this myiasis in roe deer are needed.

Seroprevalence of Toxoplasma gondii and Neospora caninum in goats from north-western Spain

INTRODUCTION AND OBJECTIVE

Toxoplasma gondii and Neospora caninum are protozoans involved in reproductive failure especially in ruminant livestock. The objective was to estimate the seroprevalence of both parasites in goats from north-western Spain and to study the influence of some factors on seropositivity.

MATERIALS AND METHOD

Blood samples from 638 goats were collected in 50 farms. Presence of T. gondii and N. caninum antibodies were detected by direct agglutination and competitiveELISA techniques, respectively. The risk factor analysis was performed using a mixed-effects logistic regression.

RESULTS

Individual (48%) and herd-level (74%) T. gondii seroprevalence values were high; the within-herd prevalence was 53%. In contrast, 6% of animals tested positive to N. caninum and 38% of the herds had at least one positive animal, with a true within-herd prevalence of 10%. Mixed infections were limited; 91% of N. caninum seropositive goats were also positive to T. gondii. The risk factor analysis showed that T. gondii seroprevalence is influenced by the presence of sheep in the farm (OR=4.9) and the seropositivity to N. caninum (OR=16.5); goats from the Central-coastal area, more humid and warm, had a 15.7-fold probability of being seropositive to T. gondii than those from the Mountainous area. Cross-breed goats (OR=4.5) and the seropositivity to T. gondii (OR= 9.5) were factors associated with N. caninum seropositivity.

CONCLUSIONS

The high T. gondii seroprevalence in goats constitute a noticeable zoonotic risk. The consideration of the risk factors identified in designing T. gondii and N. caninum control programs in goat herds should allow the implementation of more efficient measures, avoiding the appearance of outbreaks of reproductive disorders by both protozoans in goats.

Modulatory effects of interferon-γ and interleukin-4 on cellular immune responses against Hypoderma lineatum antigens

This study investigates the in vitro modulatory effects of interferon-γ (IFN-γ) and interleukin-4 (IL-4) on both proliferative bovine T cell responses and IL-10 production induced by different antigens [crude larval extract and the purified fractions hypodermin A, B and C (HyA, HyB, HyC)] obtained from first instars of Hypoderma lineatum (Diptera: Oestridae), alone or in the presence of the mitogen concanavalin A. Incubation with the different parasitic antigens resulted in significant inhibition of T cell proliferation and IL-10 production, which, in general, did not revert after the addition of IFN-γ and IL-4. In the absence of antigens, IL-4 induced significant inhibition of mitogen-induced T cell responses. Exogenous IFN-γ exhibited an inhibitory effect on cell proliferation in the presence of the purified fractions HyB and HyC. These in vitro data suggest that far from neutralizing the effects of larval antigens, the addition of IFN-γ potentiates their anti-proliferative activity; by contrast, IL-4 had no consistent effects on proliferative responses to Hypoderma. IL-4 provoked an increment of IL-10 levels in supernatants of HyB-stimulated cells. In conclusion, exogenous IFN-γ and IL-4 were unable to counteract the suppressor effects of H. lineatum antigens.

First report of Setaria tundra in roe deer (Capreolus capreolus) from the Iberian Peninsula inferred from molecular data: epidemiological implications

BACKGROUND

Filarioid nematode parasites are major health hazards with important medical, veterinary and economic implications. Recently, they have been considered as indicators of climate change.

FINDINGS

In this paper, we report the first record of Setaria tundra in roe deer from the Iberian Peninsula. Adult S. tundra were collected from the peritoneal cavity during the post-mortem examination of a 2 year-old male roe deer, which belonged to a private fenced estate in La Alcarria (Guadalajara, Spain). Since 2012, the area has suffered a high roe deer decline rate (75 %), for unknown reasons. Aiming to support the morphological identification and to determine the phylogenetic position of S. tundra recovered from the roe deer, a fragment of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene from the two morphologically identified parasites was amplified, sequenced and compared with corresponding sequences of other filarioid nematode species. Phylogenetic analyses revealed that the isolate of S. tundra recovered was basal to all other formely reported Setaria tundra sequences. The presence of all other haplotypes in Northern Europe may be indicative of a South to North outbreak in Europe.

CONCLUSIONS

This is the first report of S. tundra in roe deer from the Iberian Peninsula, with interesting phylogenetic results, which may have further implications in the epidemiological and genetic studies of these filarioid parasites. More studies are needed to explore the reasons and dynamics behind the rapid host/geographic expansion of the filarioid parasites in Europe.

Fasciola hepatica in goats from north-western Spain: Risk factor analysis using a capture ELISA

In order to study the seroprevalence of Fasciola hepatica infection in goats from north-western Spain, a total of 603 serum samples from 47 herds were tested using a capture ELISA (MM3-SERO). The identification of risk factors was assessed by a mixed-effects logistic regression analysis. The results showed that F. hepatica is widespread in this area with 57.4% of the herds and 22.7% of the animals testing positive. Breed and age were identified as determining factors for caprine F. hepatica infection. Seroprevalence in cross-bred animals was significantly higher than in the autochthonous Cabra Galega breed. A significantly higher seroprevalence was observed in older animals. The use of locally adapted breeds and the implementation of suitable management practices could provide a substantial improvement over the current F. hepatica control measures carried out in goat herds and should be considered when designing new F. hepatica control programs.

Prevalence and risk factors associated to Eimeria spp. infection in unweaned alpacas (Vicugna pacos) from Southern Peru

A total of 350 faecal samples from unweaned alpacas over 3 months of age were collected from 23 herds in order to determine the prevalence of Eimeria spp. in Southern Peru and to identify the risk factors associated to Eimeria infection in young alpacas. Samples were examined by a flotation technique and the identification of risk factors was assessed by a logistic regression analysis. Sixty four percent of the examined animals shed Eimeria oocysts; herd prevalence was 96%, with an intra-herd prevalence of 60% (range 5.9-100%). Five different Eimeria species were identified, being E. lamae (91%), E. alpacae (87%) and E. punoensis (78%) the most prevalent; E. macusaniensis (35%) and E. ivitaensis (13%) were less common. Mixed-species infections were more frequent (78%) than single infections (22%). E. lamae was the most common monospecific infection and E. lamae/E. alpacae the most frequent association. The geographical area has a significant effect on Eimeria infection rates (74.9% wet Puna vs 37.4% dry Puna) as well as the breeding system (65.1% traditional vs 63.8% modern). In contrast, the sex of the animals (64.6% males vs 64.0% females) showed no influence on the prevalence of infection by Eimeria. The high prevalence found at both individual and herd level and the common presence of highly pathogenic Eimeria species may lead to important economic losses for alpaca breeders and could require the implementation of suitable control measures.

Cryptosporidium species and subtype analysis in diarrhoeic pre-weaned lambs and goat kids from north-western Spain

Faecal specimens from diarrhoeic pre-weaned lambs (n = 171) and goat kids (n = 118) were collected in 37 sheep and 23 goat flocks, respectively, from NW Spain and microscopically examined for the presence of Cryptosporidium oocysts. Positive specimens were selected for molecular characterization. Presence of Cryptosporidium oocysts were significantly higher in specimens from goat kids (62.7%) than from lambs (31.6%). PCR products of the SSU rRNA locus were obtained for 108 isolates, and three Cryptosporidium species were identified. Cryptosporidium parvum was the most common species identified from both lambs (74.4%) and goat kids (93.8%). The remaining PCR products from lambs (25.6%) and goat kids (7.7%) were identified as Cryptosporidium Ubiquitum and Cryptosporidium xiaoi, respectively. Five C. parvum subtypes were identified; IIaA13G1R1, IIaA14G2R1, IIaA15G2R1 and IIaA16G3R1 were found in both host species, and IIdA17G1 was only detected in goat kids. Subtype IIaA15G2R1 was the most common and widely distributed. The present study provides the first description of subtypes IIaA13G1R1 in both small ruminant species, IIaA14G2R1 in sheep and IIaA16G3R1 in goats. Our results also reveal that diarrhoeic pre-weaned lambs and goat kids must be considered important reservoirs of Cryptosporidium species with zoonotic potential, such as C. parvum and C. ubiquitum.

Epidemiology of reproductive pathogens in semi-intensive lamb-producing flocks in North-West Spain: a comparative serological study

The aim of this study was to better understand the epidemiology of five major reproductive pathogens in semi-intensive lamb-producing flocks in North-West Spain. Two thousand four hundred serum samples were collected from 44 flocks, and several factors were studied to assess their influence on seropositivity. Farms that tested seropositive for more than one pathogen were common (84.1%), but seroprevalence was high only for Toxoplasma gondii (38.1%), and low for the other four pathogens, namely, Neospora caninum (5.5%), Coxiella burnetii (4.0%), Chlamydia abortus (3.9%) and Pestivirus (2.3%). Farm level exposure was highest for T. gondii and N. caninum (100% and 72.7%, respectively). For both of these pathogens, and for C. burnetii, seropositivity was associated with age and area. Farm level exposure was lowest for Pestivirus and C. abortus (13.6% and 18.2%, respectively), and, for the latter, seropositivity was principally related to flock size.

Prevalence and identity of Sarcocystis spp. in roe deer (Capreolus capreolus) in Spain: a morphological study

Muscular samples from the oesophagus, diaphragm and heart of 101 roe deer (Capreolus capreolus) hunted in Galicia (Northwestern Spain) were examined, by the compression method, for the presence of Sarcocystis spp. infection. The structure of the cyst wall was examined by light (LM) and transmission electron microscopy (TEM). The overall prevalence of infection was very high (99%), with a density of 404 cysts/sample (SD 812). The prevalence was very similar in the different examined muscle types (99% heart and diaphragm, and 98.9% oesophagus). A significantly higher intensity of infection was found in the heart (831; SD 1281), followed by the diaphragm (197; SD 190) and the oesophagus (180; SD 205). Macrocysts (>1500 μm long) were only detected in the oesophagus of 48.5% of the examined roe deer; their mean size was 2055.4 μm (SD 632.46). Cysts localised in the myocardium were significantly shorter (371.5 μm; SD 160.47) than those found in the diaphragm (678.2; SD 546) and the oesophagus (973.4 μm; SD 667.87). By LM, most of the cysts (98.8%) displayed a thin wall, which was consistent with those of Sarcocystis sp., S. gracilis and S. capreolicanis; only 1.2% of the cysts had a thick striated wall, consistent with Sarcocystis silva. Three morphological distinct sarcocysts were observed by TEM: the unnamed species Sarcocystis sp., S. capreolicanis and S. gracilis. The wall ultrastructure of the examined macrocysts was consistent with S. gracilis. This study has revealed that Spanish roe deer harbours 4 morphologically distinct types of sarcocysts; being the first record of S. gracilis in roe deer from Spain.

Evaluation of the use of pooled fecal samples for the diagnosis of protostrongylid infections in sheep

The Baermann-Wetzel method is the recommended test for the diagnosis of lungworm infections. The objective of this study was to evaluate the use of pooled fecal samples for the diagnosis of protostrongylid infections in sheep flocks and to investigate the sensitivity of the pooled Baermann-Wetzel technique in relation to individual analysis, which is time consuming and expensive. Fecal samples were taken from 10 sheep flocks positive for protostrongylids located in northwestern Spain. Ten pools composed of 6 individual fecal samples, chosen at random from the entire flock sampling, were performed for each flock at the same time as individual analyses. Protostrongylid larvae were detected in 56 pools, with a 56% flock sensitivity. Flock sensitivity was positively associated with the within-flock prevalence (P<0.001), but not with the mean larvae output. A high sensitivity (78.3%) has been observed in flocks with medium or high prevalence, so pooled fecal samples can be used in those flocks that require an effective treatment regimen against these nematodes.

Gastrointestinal nematode infections in roe deer (Capreolus capreolus) from the NW of the Iberian Peninsula: assessment of some risk factors

Intestinal contents of 218 roe deer hunted in the northwest (NW) of the Iberian Peninsula during the 2008-2009 hunting seasons were examined in order to provide information on the gastrointestinal (GI) nematode prevalence and intensity of infection and the possible influence of some environmental and intrinsic factors such as climatic conditions, age and sex. All the animals studied harboured GI nematodes, and a total of 20 different species belonging to ten genera were identified. Spiculopteragia spiculoptera/Spiculopteragia mathevossiani, Ostertagia leptospicularis/Ostertagia kolchida and Nematodirus filicollis were the most common. This is the first citation for Chabertia ovina, Cooperia pectinata, Cooperia punctata, Cooperia oncophora, Haemonchus contortus, Nematodirus spathiger, Oesophagostomum venulosum, Teladorsagia trifurcata, Trichostrongylus capricola, Trichostrongylus colubriformis, Trichostrongylus vitrinus and Trichuris capreoli in roe deer from the Iberian Peninsula. Prevalence and intensity were significantly higher in the abomasum, where infections with more than one GI nematode species were the most common; in the other intestinal segments infections with only one GI nematode species were the most prevalent. When considering the influence of the different risk factors on the prevalence of GI nematodes, the highest prevalence for most of the genera were observed in roe deer from coastal areas, where climatic conditions are more favourable for the development and survival of third stage larvae in the environment. Regarding the sex of the animals, the prevalence was, in general, higher in males than in females, probably due to behavioural and physiological sex-related differences. On the contrary, no differences were found in relation to the age of the animals. This study reveals that roe deer from the NW of the Iberian Peninsula are widely and intensely infected with gastrointestinal nematodes, which probably affect the health status of these ungulates.