Trichomonas gallinae infections in the naïve host Montifringilla nivalis subsp. nivalis

Infectious diseases bear a great risk for populations of naïve host species. In the present article we inform about the first microscopic and molecular detection of the bird pathogen Trichomonas gallinae in the White-winged Snowfinch (Montifringilla nivalis subsp. nivalis). The emergence of trichomonosis in this highly specialised alpine bird species may pose a serious threat to its already declining population. Interspecies transmission of T. gallinae most likely occurred at a bird feeder in a Swiss mountain village. Monitoring of the disease and immediate measures to prevent its spread are urgently needed.

Endoparasitoses of the Eurasian collared dove (Streptopelia decaocto) on the northern Black Sea coast of Ukraine

One of the main tasks of ecological parasitology at the present stage is to determine patterns of spread of invasive diseases of poultry in the environment through a thorough epidemiological examination, as well as to determine the main directions and factors of spread of parasites in Ukraine. Some pigeon health problems can affect their populations, but parasitic infections play an important role. Our research found that 83.3% of Eurasian collared doves examined (Streptopelia decaocto) were affected by endoparasites. The commonest helminths were Raillietina spp. with the average invasion intensity of 4.9 ± 1.3 specimens/ind., Baruscapillaria spp. and Ascaridia columbae with an invasion intensity of 4.6 ± 1.5 and 3.7 ± 2.1 specimens/ind., respectively. The commonest cestodes were Raillietina spp. with the extent of invasion of 52.2% and Davainea proglottina – 6.7%. The Amoebotaenia cuneata cestodes were recorded in 3 (3.3%) doves, and Echinolepis carioca – only in 2 (2.2%) doves. Six doves (6.7%) were infected with the nematode Ascaridia columbae and 5 (5.6%) – Baruscapillaria spp. Eimerian oocysts were found in 9 (10%) collared doves, and Trichomonas gallinae was recorded in 15 (16.7%) birds. According to the results of helminthological autopsy and identification of the isolated pathogens, 8 varieties of mixinvasions were identified. In association with the Rayetins, there were the protozoa Eimeria spp. and Trichomonas gallinae and the nematode Ascaridia columbae. Two-component invasions were registered in 78.6% of doves, three-component infestations in 14.3% and four-component infestations in 7.1% of birds. Mixed infection with Raillietina spp. + Ascaridia columbae was found in the small intestine of Streptopelia decaocto, which was also pathomorphologically observed to have catarrhal-hemorrhagic enteritis, which was accompanied by the formation of a large number of spotted hemorrhages on the mucous membrane, and in the places of attachment of cestodes - necrotic-caseous areas. Temperature and other weather conditions such as humidity, precipitation, etc. of the northern Black Sea coast affect the population size of intermediate host cestodes. Continuous monitoring of invasive diseases of pigeons of different species will help to take the necessary preventive measures against endoparasitoses of birds.

The prevalence of Trichomonas gallinae in budgerigars (Melopsittacus undulatus) in a Veterinary Clinic in Vienna between 2000–2019

The aim of this clinical retrospective study was to analyse the prevalence of Trichomonas gallinae in budgerigars (Melopsittacus undulatus). The role of T. gallinae in budgerigars as the cause of a typical clinical picture (young vomiting budgerigars) is clear; however, the frequency of latent and subclinical diseases in pet birds is unclear. Over the period of 20 years (2000–2019), 16 759 birds were examined, of which 5 256 (31.36%) belonged to the genus Melopsittacus (budgerigars). Within the 5 256 presented budgerigars, 2 547 (48.45%) were examined for trichomonads using a microscopic examination of a crop wash, and, of those, 978 birds (38.39%) were found to be positive for T. gallinae. Only 96 (9.8%) of the positive budgerigars showed typical signs of the disease, such as loss of appetite, vomiting, weight loss or anorexia. Unspecific clinical signs were seen in 312 (31.9%), while 570 birds (58.3%) did not show any clinical signs and had been presented for a routine check or other medical problems. Treatment using metronidazole (Anaerobex, Flagyl) was successful in 82–85% of these diseased birds. Trichomonads can be detected in over a third of budgerigars, even if less than 10% of the positive ones show clinical symptoms.

To get sick or not to get sick—Trichomonas infections in two Accipiter species from Germany

Trichomonosis caused by the flagellate Trichomonas gallinae is one of the most important avian diseases worldwide. The parasite is localised in the oesophageal area of its host and mainly infects pigeon and dove species. During the last decade, a host expansion to passerine birds occurred, making the disease a potential threat for passerine predators as naïve host species. Here, we investigated the effect of the parasite on two Accipiter species in Germany which show a comparable lifestyle but differ in prey choice, the Northern goshawk (Accipiter gentilis) mainly hunting pigeons and the Eurasian sparrowhawk (Accipiter nisus) mainly feeding on passerines. We genetically identified the parasite strains using the Fe-Hydrogenase gene as marker locus and compared the incidence of parasite presence and clinical signs of trichomonosis between nestlings of the two Accipiter species. In total, we identified 14 strains, with nine strains unknown so far. There was a higher strain diversity and prevalence of Trichomonas spp. in goshawks than sparrowhawks (42.4% vs. 21.2%) whereas sparrowhawks when being infected more often displayed clinical signs of trichomonosis than goshawks (37.1% vs. 6.1%). Even though sparrowhawks were mainly infected with the finch epidemic strain and genetic data indicated some variation between isolates, no correlation with virulence could be detected. All in all, goshawks seem to be better adapted to Trichomonas infections, whereas to sparrowhawks, this is a novel disease with more severe manifestations, from individual morbidity to a higher risk of population decline caused by trichomonosis.

Antiparasitic Effects of Potentially Toxic Beetles (Tenebrionidae and Meloidae) from Steppe Zones

Arthropods and specifically beetles can synthesize and/or sequester metabolites from dietary sources. In beetle families such as Tenebrionidae and Meloidae, a few studies have reported species with toxic defensive substances and antiparasitic properties that are consumed by birds. Here we have studied the antiparasitic activity of extracts from beetle species present in the habitat of the Great Bustard (Otis tarda) against four pathogen models (Aspergillus niger, Meloidogyne javanica, Hyalomma lusitanicum, and Trichomonas gallinae). The insect species extracted were Tentyria peiroleri, Scaurus uncinus, Blaps lethifera (Tenebrionidae), and Mylabris quadripunctata (Meloidae). M. quadripunctata exhibited potent activity against M. javanica and T. gallinae, while T. peiroleri exhibited moderate antiprotozoal activity. The chemical composition of the insect extracts was studied by gas chromatography coupled with mass spectrometry (GC-MS) analysis. The most abundant compounds in the four beetle extracts were hydrocarbons and fatty acids such as palmitic acid, myristic acid and methyl linoleate, which are characteristic of insect cuticles. The presence of cantharidin (CTD) in the M. quadripunctata meloid and ethyl oleate (EO) in T. peiroleri accounted for the bioactivity of their extracts.

Parasites of domestic and wild pigeons in the south of Ukraine

Pigeons are closely related to human life and are both a source of food and object for hobbies and sports. Parasitic diseases of birds are the main reason for their growth retardation, reduced productivity and viability. The article presents the results of studying the prevalence of trichomonosis, cestodes and nematodes among the population of wild and domestic pigeons in the south of Ukraine. According to the results of the conducted researches it is established that in the south of Ukraine endoparasitoses of domestic and wild pigeons are quite widespread, and all species of this bird are carriers of Trichomonas gallinae. At the same time, the highest rate of Trichomonas infection was recorded in Columba palambus and C. livia domestica, and the overall infestation of males is higher by 4.4% compared to females. It was determined that domestic pigeons C. livia domestica were infested with trichomonosis (27.5%) and nematodes (Ascaridia columbae, 57.1%), C. palambus – trichomonosis (32.1%) and cestodes (Raillietina spp., 82.4%), Streptopelia turtur – cestodes (Raillietina spp., 12.5%) and S. decaocto – cestodes (Raillietina spp., 71.4%) and nematodes (Heterakis gallinarum, A. columbae – 33.3% and 44.4% respectively). The overall rate of infestation of pigeons with cestodes was 28.4% and the incidence in males was higher by 3.9% compared to females. It was found that the most common species among pigeon cestodes is Raillietina spp. In addition, 22.9% of pigeons are carriers of nematodes (H. gallinarum, A. columbae and Capillaria spp.). Continuous monitoring of pigeon parasites is necessary because they, in most cases, come into contact with other species of poultry and are a source of general invasion. In terms of further research, it would be promising to study the prevalence of helminthic infestation among wild migratory birds.