Genome analysis of gyroviruses identified in waterfowl in Arizona (USA).

Gyroviruses are small single-stranded DNA (ssDNA) viruses that are largely associated with birds. Chicken anemia virus is the most extensively studied gyrovirus due to its disease impact on the poultry industry. However, we know much less about gyroviruses infecting other avian species. To investigate gyroviruses infecting waterfowl, we determined six complete genome sequences that fall into three gyrovirus groups, referred to as waterfowl gyrovirus 1 (n = 3), 2 (n = 2), and 3 (n = 1), in organs from hunter-harvested waterfowl from Arizona (USA). The waterfowl gyrovirus 1 variants were identified in multiple organs of a single American wigeon and represent a tentative new species. The waterfowl gyrovirus 2 variants were identified in the livers of two American wigeons and share >70% VP1 nucleotide sequence identity with gyrovirus 9, previously identified in the spleen of a Brazilian Pekin duck (MT318123) and a human fecal sample (KP742975). Waterfowl gyrovirus 3 was identified in a northern pintail spleen sample, and it shares >73% VP1 nucleotide sequence identity with two gyrovirus 13 sequences previously identified in Brazilian Pekin duck spleens (MT318125 and MT318127). These gyroviruses are the first to be identified in waterfowl in North America, as well as in American wigeons and northern pintails.

Body condition and poxvirus infection predict circulating glucose levels in a colorful songbird that inhabits urban and rural environments.

There is widespread contemporary interest in causes and consequences of blood glucose status in humans (e.g., links to diabetes and cardiovascular disease), but we know comparatively less about what underlies variation in glucose levels of wild animals. Several environmental factors, including diet, disease status, and habitat quality, may regulate glucose circulation, and we are in need of work that assesses many organismal traits simultaneously to understand the plasticity and predictability of glucose levels in ecological and evolutionary contexts. Here, we measured circulating glucose levels in a species of passerine bird (the house finch, Haemorhous mexicanus) that has served as a valuable model for research on sexual selection, disease, and urban behavioral ecology, as these animals display sexually dichromatic ornamental coloration, harbor many infectious diseases (e.g., poxvirus, coccidiosis, mycoplasmal conjunctivitis), and reside in both natural habitats and cities. We tested the effects of sex, habitat type, body condition, coccidiosis and poxvirus infections, and expression of carotenoid plumage coloration on blood glucose concentrations and found that the body condition and poxvirus infection significantly predicted circulating glucose levels. Specifically, birds with higher blood glucose levels had higher body condition scores and were infected with poxvirus. This result is consistent with biomedical, domesticated-animal, and wildlife-rehabilitation findings, and the premise that glucose elevation is a physiological response to or indicator of infection and relative body weight. The fact that we failed to find links between glucose and our other measurements suggests that blood glucose levels can reveal some but not all aspects of organismal or environmental quality.