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Toxoplasma gondii infections are common in humans and animals worldwide. Wild and domestic avian species are important in the epidemiology of T. gondii infections because felids prey on them and excrete millions of oocysts in the environment, disseminating the infection. Herbivorous birds are also excellent sentinels of environmental contamination with T. gondii oocysts because they feed on the ground. Toxoplasma gondii infections in birds of prey reflect infections in intermediate hosts. Humans can become infected by consuming undercooked avian tissues. Here, the authors reviewed prevalence, persistence of infection, clinical disease, epidemiology and genetic diversity of T. gondii strains isolated from turkeys, geese, ducks, ratites and avian species (excluding chickens) worldwide 2009–2020. Genetic diversity of 102 T. gondii DNA samples isolated worldwide is discussed. The role of migratory birds in dissemination of T. gondii infection is discussed.

The aim of this investigation was to determine the histological differences of anatomical regions of the ureter in Japanese quail compared with some other domestic avian species such as pigeon, European starling and fowl. Tissue samples from proximal, middle and distal regions of each ureter were obtained and stained with H & E, Alcian blue (pH 2.5), Periodic acid-Schiff, Masson's trichrome, Verhoeff's, and Gomori's method for reticulum. The histology and histochemistry of the ureter showed considerable differences among various anatomical regions of the ureter. No significant sex-based differences were found. The primary branches of ureter were composed of tunica mucosa, submucosa, muscularis and serosa, whereas the wall of smaller branches of ureter only consisted of epithelium and connective tissue fibers. The intraepithelial glands were not found in some region of ureter. The mucosal folds and microvilli were more identified in the proximal region than those of the other regions of the organ. The simple columnar epithelium of proximal region was changed to pseudostratified columnar in other regions of the ureter. In all different regions of ureter, lymphatic tissues were not observed in the lamina propria. The thickness of the tunica muscularis increased from the proximal to the distal region of the ureter. Unusual findings of the ureter in Japanese quail were the presence of reticular, elastic and collagenous fibers in all the connective tissues of organ, isometric longitudinal folds and muscularis mucosa.

International audience; Influenza A (H9N2) viruses are a genetically diverse population that infects wild and domestic avian species and mammals and contributed the internal gene segments to the A/H5N1 and A/H7N9 viruses associated with lethal human infections. Here we comprehensively assess the potential risk to mammals of a diverse panel of A/H9N2 viruses, representing the major H9N2 clades, using a combination of in vitro assays (e.g., antiviral susceptibility and virus growth in primary differentiated human airway cells) and in vivo assays (e. g., replication, transmission and/or pathogenicity of viruses in ducks, pigs, mice and ferrets). We observed that viruses isolated from humans, A/Hong Kong/1073/1999 and A/Hong Kong/33982/2009, had the highest risk potential. However, the A/swine/Hong Kong/9A-1/1998 and A/chicken/Hong Kong/G9/1997 viruses also displayed several features suggesting a fitness profile adapted to human infection and transmission. The North American avian H9N2 clade virus had the lowest risk profile, and the other viruses tested displayed various levels of fitness across individual assays. In many cases, the known genotypic polymorphisms alone were not sufficient to accurately predict the virus' phenotype. Therefore, we conclude that comprehensive risk analyses based on surveillance of circulating influenza virus strains are necessary to assess the potential for human infection by emerging influenza A viruses.

A deterministic bio-economic model was developed to support breeding of indigenous chicken and used to evaluate biological and economic variables that characterise indigenous chicken (Gallus domesticus) production systems in Kenya. The systems were defined on the basis of the feeding regime, level of confinement and healthcare provided and included; confined full ration system, where the chicken are confined all the time and provided with commercial feed and proper healthcare; semi-intensive system, where the chicken are confined part of the time and given crop residues and kitchen waste, with no healthcare; and free range system, where the chicken are left to roam around the homestead picking whatever feed resource they get and without healthcare. The input parameters are divided into four categories: biological variables which include animal traits, managemental variables, nutritional variables and economic variables. These parameters assume typical indigenous chicken production in Kenya . However, the input parameters may be adjusted to suit specific situations and also assess the biological and economic performance of various production systems of other domestic avian species. The model's ability to simulate live weight changes, feed intake of various chicken categories, revenues, cost and profitability of the three production systems is illustrated. The bio-economic models can be used to develop breeding goals and estimate economic values for the genetic improvement of indigenous chicken.

Much of the information previously available concerning avian clinical pathology was drawn from data from domestic avian species, in particular, poultry. Clinical pathology of nondomestic avian species such as psittacines, however, has come a long way toward establishing normal reference values for caged birds. As a result, it is important for the avian clinician to learn which clinical tests can be used to detect and evaluate a single disease or disease processes by learning what information is gained from hematologic, biochemical, or cytologic samples acquired during a patient's clinical examination.

In domestic avian species, eggs are stored at cool temperatures until they can be placed into an incubator. The low temperature-induced diapause enables the embryo to survive until optimal temperature and humidity incubation conditions can be provided to support embryonic growth. Egg storage is a logistical necessity for the hatching egg industry both at the breeder farm and at the hatchery. However, it is well known that egg storage longer than 7 d negatively influences hatchability. At the cellular level, long-term egg storage induces cell death. This appears to be occurring both via necrosis and apoptosis. The result is higher embryonic mortality and, consequently, lower hatchability. In addition, long-term egg storage influences embryonic development and metabolism. Embryos of eggs stored long-term can be affected such that they do not initiate growth after proper incubation temperatures are provided; they initiate growth, but grow at a slower rate than eggs stored short term; and they are affected in both of the previously mentioned ways. Development of equipment to measure the embryonic metabolism of individually incubating eggs over the entire 21 d of incubation has provided further evidence that embryo metabolism has changed due to storage. One of the methods to reduce the negative effects of long-term storage has been to incubate eggs for short periods before storage. In both turkey and chicken eggs, this technique has been successful in improving the hatchability of long-term stored eggs. It is hypothesized that particular embryonic developmental stages are better able to survive long-term storage. Future research should focus on the mechanisms behind this improved ability to survive storage.

The embryotoxicity of an artificial mixture of 18 polycyclic aromatic hydrocarbons (PAHs) was tested by injection into the yolk sacs of eggs of four avian species: chicken Gallus domesticus, turkey Meleagris gallopavo, domestic duck Anas platyrhynchos and common eider Somateria mollissima. A dose of 2·0 mg kg egg−1 of the PAH mixture increased the mortality among the embryos of all four species. In the domestic duck, but not in the three other species, there was a significantly increased embryonic mortality at a dose of 0·2 mg kg−1 of this mixture. All 18 individual compounds in the mixture were tested for embryotoxicity in the chicken. The compound most toxic to chick embryos was benzo[k]fluoranthene. This substance also proved to be highly embryotoxic in the three other species. Previous studies have shown coplanar polychlorinated biphenyls (PCBs) to be much more embryotoxic in the chicken than in other avian species studied. In accordance with this, eider duck embryos proved to be considerably less sensitive to 3,3′,4,4′-tetrachlorobiphenyl and 3,3′,4,4′,5-pentachlorobiphenyl than was previously found for chick embryos. For PAHs, however, chick embryos did not have a higher sensitivity than the other species tested.