The resistance of Eimeria spp. to toltrazuril in black grouse (Lyrurus tetrix) kept in an aviary

Occurrence and molecular characterization of Escherichia coli strains isolated from black grouse (Lyrurus tetrix) from the Karkonosze National Park in Poland

The purpose of this study was to characterize Escherichia coli (E. coli) strains isolated from wild black grouse (Lyrurus tetrix), carried out due to the crossing of hiking trails with wild bird habitats from the Karkonosze National Park. Twenty-seven E. coli isolates were obtained from fecal samples collected during the winter months of 2017 and 2018. The strains were assigned to their relevant phylo-groups and the prevalence of virulence genes characteristic of APEC strains (irp2, astA, iss, iucD, papC, tsh, vat, cva/cvi, stx2f) was checked using PCR analysis. In addition, the phenotypic and genotypic resistance to antibiotics was determined. The entire study provided a better understanding of the potential bacteriological threat to wild birds of the Karkonosze National Park. The results showed that 55.6% of the strains belonged to phylo-group B1 (15/27), 33.3% to group B2 (9/27) and 11.1% to group D (3/27). Among the virulence genes tested, irp2 was detected in 25.9% of isolates (7/27), vat in 22.2% (6/27) and iucD in 3.7% (1/27). The tested E. coli strains showed susceptibility to most antimicrobials, only 14 (51.9%) of them were intermediate resistant or resistant to sulfamethoxazole. The presence of none of the tested genes responsible for resistance to selected antibiotics was identified. Our research indicates a low level of transfer of antimicrobial substances to the natural environment and confirms the effectiveness of the Karkonosze National Park's activities to protect and restore black grouse habitats.

XENOFOOD—An Autoclaved Feed Supplement Containing Autoclavable Antimicrobial Peptides—Exerts Anticoccidial GI Activity, and Causes Bursa Enlargement, but Has No Detectable Harmful Effects in Broiler Cockerels despite In Vitro Detectable Cytotoxicity on LHM Cells

Entomopathogenic bacteria are obligate symbionts of entomopathogenic nematode (EPN) species. These bacteria biosynthesize and release non-ribosomal-templated hybrid peptides (NR-AMPs), with strong, and large-spectral antimicrobial potential, capable of inactivating pathogens belonging to different prokaryote, and eukaryote taxa. The cell-free conditioned culture media (CFCM) of Xenorhabdus budapestensis and X. szentirmaii efficiently inactivate poultry pathogens like Clostridium, Histomonas, and Eimeria. To learn whether a bio-preparation containing antimicrobial peptides of Xenorhabdus origin with accompanying (in vitro detectable) cytotoxic effects could be considered a safely applicable preventive feed supplement, we conducted a 42-day feeding experiment on freshly hatched broiler cockerels. XENOFOOD (containing autoclaved X. budapestensis, and X. szentirmaii cultures developed on chicken food) were consumed by the birds. The XENOFOOD exerted detectable gastrointestinal (GI) activity (reducing the numbers of the colony-forming Clostridium perfringens units in the lower jejunum. No animal was lost in the experiment. Neither the body weight, growth rate, feed-conversion ratio, nor organ-weight data differed between the control (C) and treated (T) groups, indicating that the XENOFOOD diet did not result in any detectable adverse effects. We suppose that the parameters indicating a moderate enlargement of bursas of Fabricius (average weight, size, and individual bursa/spleen weight-ratios) in the XENOFOOD-fed group must be an indirect indication that the bursa-controlled humoral immune system neutralized the cytotoxic ingredients of the XENOFOOD in the blood, not allowing to reach their critical cytotoxic concentration in the sensitive tissues.

ENDOPARASITES IN WESTERN CAPERCAILLIES (TETRAO UROGALLUS) AND BLACK GROUSE (TETRAO TETRIX) KEPT IN VARIOUS TYPES OF AVIARIES

Gallinaceous birds, including Western Capercaillies (Tetrao urogallus) and Black Grouse (Tetrao tetrix), are kept in aviaries and reintroduced to natural habitats as a part of ongoing measures to protect these endangered species. Although parasitic loads can immensely affect reintroduction success of these species, little is known about how the infestation level varies in birds reared with different methods. The aim of this study was to determine the prevalence of endoparasites in fecal samples collected from Galliformes kept in various types of aviaries and transported to reintroduction sites. Most parasitic infections in the examined birds were caused by protozoa of the genus Eimeria, including Eimeria lyruri and Eimeria procera in Western Capercaillies, and E. lyruri, Eimeria nadsoni, and Eimeria tetricis in Black Grouse, which also hosted nematodes of the Capillaria spp. and Ascaridia galli. The prevalence of parasites varied across different types of aviaries. In permanent aviaries, Eimeria spp. was detected in 36% and 35% of the fecal samples collected from Western Capercaillies and Black Grouse, whereas Capillaria spp. were identified in 41% and 69% of the samples, respectively. The prevalence of the identified parasites increased in permanent aviaries on the second sampling date. In contrast, birds kept in seminatural free-flight aviaries in line with the "born to be free" rearing method had a lower prevalence of these parasites. Galliformes housed in seminatural aviaries may be better prepared for reintroduction to their natural habitats.

Changes in the corticosterone level in tooting male black grouse (Tetrao tetrix) infected with Eimeria spp

The black grouse (Tetrao tetrix) is a forest bird species critically endangered of extinction. Enclosed aviary breeding is among the measures taken to protect the species. Complex factors can affect its reproduction success, including coccidiosis. In this article, corticosterone level (as a reliable biomarker of stress in birds) and prevalence of Eimeria spp. were determined in male black grouse kept in aviary breeding center before, during, and after the reproductive season (called tooting). The correlation between those parameters was also analyzed. The corticosterone level was measured with noninvasive method in fecal samples in an immunoassay. The prevalence of Eimeria spp. was determined by the qualitative (Fülleborn's flotation) and quantitative method (McMaster's method as modified by Raynaud). Results show the occurrence of 3 species of Eimeria spp. in males: Eimeria lyruri, Eimeria nadsoni, and Eimeria nonbrumpti. Infestation with E. lyruri was chronic in nature. A co-invasion of E. lyruri, E. nadsoni, and E. nonbrumpti was observed during (prevalence 60%) and after the tooting (prevalence 40%). The study showed no statistical changes in the oocysts per 1 g of feces (CORTl) and oocysts per 1 g of feces (OPG) in assays I-III and absence of correlation between CORTl and OPG. The results of this experiment do not support the hypothesis that chronic infestation with Eimeria spp. can induce chronic stress in grouse. But may suggest that males of black grouse are susceptible to infestation with other species of Eimeria spp. during mating season. The knowledge of the level of individual stress and parasitic infestation can be used to take protective actions for this bird species, especially to achieve higher survival rate and bird reproduction rate. Tangible effects will include an assessment of the relationship between individual susceptibility and chronic environmental stress caused by coccidia.

Clinical Management of Avian Renal Disease

Treatment of avian renal disease relies on supportive care, such as fluid therapy and nutritional support. Analgesia and adaptations of the environment are indicated in cases of renal disease associated with painful joints. Other treatments vary with the underlying etiology and may include systemic antibiotics, antifungal therapy, vitamin A supplementation, or chelation therapy.