Respiratory tract infection caused by Mycobacterium bovis in a black swan (Cygnus atratus)

Winter breeding of black swan Cygnus atratus in a solar greenhouse with a water pond

Winter propagation of black swans Cygnus atratus is introduced at Kwangpho on the east coast of the Democratic People's Republic of Korea located in the temperate zone of northeast Asia. The natural lake Kwangpho was selected as a rearing site to provide the environment which matched most closely to black swan's natural habitats. Comparison of the climate data of Kwangpho with Australia and New Zealand led to the conclusion that it is necessary to increase winter temperature 10 °C for artificial rearing. In order to overcome the low temperature with renewable energy, a passive solar greenhouse with a water pond was introduced, where black swans were reared simultaneously while observing the microclimate such as air temperature, humidity and water temperature in winter. When the pond depth was 0.4 m and 0.8 m, there was no significant difference in indoor temperature, the depth fixed at 0.4 m to reduce pumping power by more than 50%. During the study, 80 mature black swans wintered safely and 13 pairs of them laid 74 eggs, the artificial hatching rate was 65% and the natural hatching rate was 53%. It was confirmed that the passive solar greenhouse with a pond can raise the winter minimum temperature 8-10 °C higher than outside, and in this microclimate it is possible to propagate the black swan and it is believed that the greenhouse has abundant potential to enable the artificial breeding as well as wintering of black swans, in temperate zone occupying wide area of the earth.

Plumage microbiota covaries with the major histocompatibility complex in blue petrels

To increase fitness, a wide range of vertebrates preferentially mate with partners that are dissimilar at the major histocompatibility complex (MHC) or that have high MHC diversity. Although MHC often can be assessed through olfactory cues, the mechanism by which MHC genes influence odour remains largely unclear. MHC class IIB molecules, which enable recognition and elimination of extracellular bacteria, have been suggested to influence odour indirectly by shaping odour-producing microbiota, i.e. bacterial communities. However, there is little evidence of the predicted covariation between an animal's MHC genotype and its bacterial communities in scent-producing body surfaces. Here, using high-throughput sequencing, we tested the covariation between MHC class IIB genotypes and feather microbiota in the blue petrel (Halobaena caerulea), a seabird with highly developed olfaction that has been suggested to rely on oduor cues during an MHC-based mate choice. First, we show that individuals with similar MHC class IIB profiles also have similar bacterial assemblages in their feathers. Then, we show that individuals with high MHC diversity have less diverse feather microbiota and also a reduced abundance of a bacterium of the genus Arsenophonus, a genus in which some species are symbionts of avian ectoparasites. Our results, showing that feather microbiota covary with MHC, are consistent with the hypothesis that individual MHC genotype may shape the semiochemical-producing microbiota in birds.