Susceptibility to intestinal parasites and juvenile survival are correlated with multilocus microsatellite heterozygosity in the Capercaillie (Tetrao urogallus)

Inbreeding can have a negative influence on several life-history traits as well as disease resistance in birds and mammals through different geneticmechanisms. Endangered and declining populationsmay be at particular risk for inbreeding. The level of inbreeding can be estimated by assessing individual heterozygosity at neutralmicrosatellitemarkers.We studied the relationships between intestinal helminth infections, age, sex and heterozygosity in Capercaillie (Tetrao urogallus).We assessedmicrosatellite heterozygosity at eight autosomal loci and calculated two different indices (multilocus heterozygosity MLH and mean d 2) to quantify individual heterozygosity. Capercaillie were infected by three species of cestodes (Paroniella urogalli, Skrjabinia cesticillus and Hymenolepis sp.) and one nematode species (Ascaridia compar).We found that the probability of nematode infection decreased as the level of heterozygosity (measured by mean d 2) increased. Also, the intensity of nematode infection decreased as heterozygosity (measured by MLH) increased. However, we did not observe correlation between heterozygosity and the occurrence of cestodes. In addition, heterozygosity (bothMLHandmean d 2)was dependent on age class: adultCapercaillie had higher heterozygosity than juveniles. Results suggest selection for heterozygosity which can be reinforced by differences in genetic parasite resistance

Orthomyxo-, paramyxo- and flavivirus infections in wild waterfowl in Finland

<p>Abstract</p> <p>Background</p> <p>Screening wild birds for viral pathogens has become increasingly important. We tested a screening approach based on blood and cloacal and tracheal swabs collected by hunters to study the prevalence of influenza A, paramyxo-, flavi-, and alphaviruses in Finnish wild waterfowl, which has been previously unknown. We studied 310 blood samples and 115 mixed tracheal and cloacal swabs collected from hunted waterfowl in 2006. Samples were screened by RT-PCR and serologically by hemagglutination inhibition (HI) test or enzyme-linked immunosorbent assay (ELISA) for influenza A (FLUAV), type 1 avian paramyxo-(APMV-1), Sindbis (SINV), West Nile (WNV) and tick-borne encephalitis (TBEV) virus infections.</p> <p>Results</p> <p>FLUAV RNA was found in 13 tracheal/cloacal swabs and seven strains were isolated. Five blood samples were antibody positive. Six APMV-1 RNA-positive samples were found from which four strains were isolated, while two blood samples were antibody positive. None of the birds were positive for flavivirus RNA but three birds had flavivirus antibodies by HI test. No antibodies to SINV were detected.</p> <p>Conclusion</p> <p>We conclude that circulation of both influenza A virus and avian paramyxovirus-1 in Finnish wild waterfowl was documented. The FLUAV and APMV-1 prevalences in wild waterfowl were 11.3% and 5.2% respectively, by this study. The subtype H3N8 was the only detected FLUAV subtype while APMV-1 strains clustered into two distinct lineages. Notably, antibodies to a likely mosquito-borne flavivirus were detected in three samples. The screening approach based on hunted waterfowl seemed reliable for monitoring FLUAV and APMV by RT-PCR from cloacal or tracheal samples, but antibody testing in this format seemed to be of low sensitivity.</p

Population cycles and outbreaks of small rodents : ten essential questions we still need to solve

Correction: 10.1007/s00442-021-04856-4, Oecologia (2021)Most small rodent populations in the world have fascinating population dynamics. In the northern hemisphere, voles and lemmings tend to show population cycles with regular fluctuations in numbers. In the southern hemisphere, small rodents tend to have large amplitude outbreaks with less regular intervals. In the light of vast research and debate over almost a century, we here discuss the driving forces of these different rodent population dynamics. We highlight ten questions directly related to the various characteristics of relevant populations and ecosystems that still need to be answered. This overview is not intended as a complete list of questions but rather focuses on the most important issues that are essential for understanding the generality of small rodent population dynamics.Peer reviewe

Sindbis Virus Infection in Resident Birds, Migratory Birds, and Humans, Finland

Resident grouse may be involved in the epidemiology of SINV in humans

Polyterritorial polygyny in the pied flycatcher

After having attracted their first female most pied flycatcher (Ficedula hypoleuca) males establish a second, spatially separate, territory and attempt to attract a second female there. Some males succeed in attracting the second female. Polygynous mating is costly for a secondary female since males feed primarily the young of the primary female and many of secondary females have to raise their nestlings alone. Why are males polyterritorial and why do some females accept a secondary status? First, males may space out territories in order to hide their mating status and therefore females are deceived into polygyny against their best interests. Alternatively, males may be polyterritorial to reduce aggression between their two mates. Some females may do their best by accepting polygyny because the cost of searching for an unmated male may exceed the cost of reduced male assistance. Females did not effectively avoid polygyny even though there were optional unmated males close by and it would have been adaptive to mate with an unmated male. There were some cues females might have been able to use to estimate male's mating status. Already mated polyterritorial males spent less time and sang less on their second territories than did unmated males on their single territories. The overlap in behaviour of males of different mating status might prevent females to accurately determine male's mating status. The power of female aggression seemed to be too weak to prevent male's secondary mating even when the distance between territories was short. The most plausible explanation for polyterritorial polygyny in the pied flycatcher is that males derive benefits from imperfect female choice by being polyterritorial