Molecular identification of Sarcocystis halieti in the muscles of two species of birds of prey from Spain.

BACKGROUND: Members of the genus Sarcocystis are protozoan parasites characterized by a prey-predator two-host life-cycle. Sarcocysts are formed in the muscles or central nervous system of the intermediate host (IH), while sporocysts develop in the small intestine of the definitive host (DH). Various birds of prey have been confirmed to be DH for Sarcocystis spp. Three Sarcocystis species, S. wobeseri, S. halieti and S. falcatula, have been identified in the muscles of birds of prey, of which the latter are known to be pathogenic and can cause encephalitis in various birds. The aim of this study was to identify Sarcocystis spp. in the muscles of birds of prey from Spain. METHODS: Between 2019 and 2020, muscle tissue samples taken from 59 birds of prey admitted to the Wildlife Recovery Centre in Ilundain (Navarra, Spain) were examined for the presence of Sarcocystis spp. Sarcocysts in fresh squashed samples were morphologically characterized under the light microscope (LM). Sarcocystis spp. were identified by means of 28S ribosomal RNA and internal transcribed spacer 1 sequence analysis. RESULTS: Microscopic examination of squashed tissue samples stained with methylene blue revealed the presence of sarcocysts in three of the 59 (5.1%) birds examined. Only one sarcocyst type was observed under the LM. Sarcocysts were thread-like (1050-2160 × 130-158 µm) and had a thin (0.7-1.4 µm) and smooth cyst wall. Septa divided the cysts into compartments filled with banana-shaped (5.9 × 1.7 µm) bradyzoites. On the basis of DNA sequence results, S. halieti was identified in the western marsh harrier (Circus aeruginosus) and the black kite (Milvus migrans) for the first time. Sarcocysts of S. halieti were shorter and wider compared to those observed in the great cormorant (Phalacrocorax carbo) and the herring gull (Larus argentatus). According to current knowledge, S. halieti may infect birds belonging to four different orders: Suliformes, Charadriiformes, Strigiformes and Accipitriformes. CONCLUSIONS: This is the first report of S. halieti in the western marsh harrier and the black kite as IH. So far, little research has been conducted on birds of prey as IH for Sarcocystis spp. These results indicate that further studies combining morphological, histopathological, and molecular methods are required.

Molecular epidemiology of human and bovine anaplasmosis in southern Europe.

The genus Anaplasma (Rickettsiales: Anaplasmataceae) includes several pathogens such as A. marginale and A. phagocytophilum that have an impact on veterinary and human health. In this study, we characterized A. marginale and A. phagocytophilum infections in humans, wild and domestic animals, and ticks in southern Europe (particularly in south-central Spain and in Sicily) by means of serologic study, PCR, and sequence analysis of major surface proteins (msp) 1alpha and 4 and 16S rDNA. The results suggest that A. marginale infections in this region are maintained in cattle and deer, with ticks and tabanids serving as biological and mechanical vectors of the pathogen, respectively. Infections with A. phagocytophilum may occur in humans and are maintained in cattle, donkeys, deer, and birds and are most likely transmitted by several tick species with as yet an unknown role as reservoir hosts for other wild and domesticated mammals. The presence of concurrent infections in cattle and deer suggests that these pathogens may multiply in the same reservoir host and illustrates the complexity of the epidemiology of bovine and human anaplasmosis in this region.

Seroprevalence of six reproductive pathogens in European wild boar (Sus scrofa) from Spain: the effect on wild boar female reproductive performance.

We studied the seroprevalence of six reproductive pathogens in Spanish hunter-harvested wild boar females. The sample was representative of the hunting harvest in the studied hunting estates. Mean antibody prevalences were: 60.6+/-0.06% for Aujeszky's disease virus (ADV), 56.6+/-0.09% for porcine parvovirus (PPV), 51.8+/-0.06% for porcine circovirus type 2 (PCV2), 29.7+/-0.09% for Brucella spp. and 36.3+/-0.1% for Toxoplasma gondii. We did not detect antibodies against porcine reproductive and respiratory syndrome virus (PRRSv). ADV seroprevalence was associated with PPV and PCV2 seroprevalence in Spanish wild boar females. Ovulation rate in the studied wild boar females was 4.41+/-0.16 (n=120), mean litter size was 3.91+/-0.16 (n=82) and the partial resorption index 0.92+/-0.17 (n=66). Ovulation rate and litter size were statistically associated with age. T. gondii seroprevalence was negatively related to ovulation rate and partial resorption index. Wild boars from managed fenced estates had antibodies against more pathogens than wild boars from open estates. Potential relations between management of wild boar populations and exposure of individuals to different reproductive pathogens are discussed.

Potential vertebrate reservoir hosts and invertebrate vectors of Anaplasma marginale and A. phagocytophilum in central Spain.

Organisms in the genus Anaplasma are obligate intracellular pathogens that multiply in both vertebrate and invertebrate hosts. The type species, A. marginale, causes bovine anaplasmosis and only infects ticks and ruminants. A. phagocytophilum causes human and animal granulocytic anaplasmosis, and genetically closely related strains show a wide host range, including ticks, ruminants, rodents, equids, canids, birds, and humans. Recent reports demonstrated that A. marginale and A. phagocytophilum co-exist in geographic areas and that concurrent infections occur in ruminants and ticks. In this study, we characterized A. marginale and A. phagocytophilum infections in wild and domestic animals, and ticks collected in central Spain by serology, PCR, and sequence of 16S rRNA genotypes. Species tested included humans, cattle, dogs, rodents, Iberian red deer, European wild boar, birds, and ticks. Species of hematophagous Diptera were analyzed as potential mechanical vectors of Anaplasma spp. A. marginale was detected in tabanids, ticks, cattle, and deer, while A. phagocytophilum was detected in ticks, deer, cattle, and birds. Concurrent infections of the two Anaplasma were found in cattle and deer. These results illustrate the complexity of the epizootiology of A. marginale and A. phagocytophilum in regions where both pathogens co-exist and share common reservoir hosts and vectors. The increasing contact between wildlife, domestic animals, and human populations increases the risk of outbreaks of human and bovine anaplasmosis, and the difficulty of implementing surveillance and control measures.