Data from: Survey of haemosporidian parasites in resident and migrant game birds of Illinois

Haemosporidian parasites are globally distributed in avian species, capable of leading to decreased reproductive success, weakness and mortality. Haemosporidian parasites that affect reproduction and population growth are of interest to bird conservation groups and to organizations concerned with the health and immunological status of avian populations. Haemosporidian infection data are not always available for some avian species in specific regions yet. These data provides the starting points to evaluate geographical and temporal changes in the patterns of infection and prevalence across populations. We examined haemoparasite infections in four game bird species commonly hunted in Illinois. Prevalence, mean intensity, median intensity and mean abundance of haemosporidians were calculated, and the relation of these infection measures associated with age and sex of the avian hosts were evaluated. Game species sampled (n = 237) included migrants such as mourning doves (Zenaida macroura), wood ducks (Aix sponsa) and Canada geese (Branta canadensis), as well as resident birds such as wild turkeys (Meleagris gallopavo). Only Haemoproteus, Plasmodium, and Leucocytozoon species were identified. Haemoproteus was the most prevalent haemosporidian (46/237), followed by Plasmodium (11/237). Furthermore, Haemoproteus was the most persistent haemosporidian, as it was the only parasite genera found in all four avian species. Co-infections were found in 55% of turkeys, but no significant correlations between the genera of haemosporidinan co-infections and a host species were found. Moreover, no significant differences in the proportion of infected individuals (prevalence) and haemosporidian quantities (levels of intensity and abundance) were related to biotic factors such as age and sex of the host. However, parasite aggregation (distribution of parasites among hosts) was affected by age, as adult turkeys and juvenile doves showed the highest aggregation index (Poulin’s index of discrepancy D) for Haemoproteus spp. This study reveals patterns of infection and parasite aggregations that vary widely among different game bird species and provides baseline data on avian haemosporidians that, to the best of our knowledge, is not currently available in the state of Illinois for these avian species. Finally, these patterns can be used for management of landscape or host species to support conservation efforts.

血孢子虫（Haemosporidian）在全球鸟类种群中广泛分布，可导致宿主繁殖成功率下降、体质衰弱乃至死亡。那些影响宿主繁殖与种群增长的血孢子虫，是鸟类保护组织以及关注鸟类种群健康与免疫状态的机构重点关注的对象。目前，部分区域的部分鸟类物种仍缺乏相关的血孢子虫感染数据。此类数据可为评估不同种群间感染模式与流行率的地理及时间变化提供基础依据。本研究针对伊利诺伊州常见的四种猎用鸟类开展了血寄生虫感染调查。研究计算了血孢子虫的感染流行率（prevalence）、平均感染强度（mean intensity）、中位感染强度（median intensity）以及平均感染丰度（mean abundance），并分析了这些感染指标与鸟类宿主年龄和性别的关联。本次共采样237只猎用鸟类，包括迁徙性物种（如哀鸽Zenaida macroura、林鸳鸯Aix sponsa与加拿大黑雁Branta canadensis）以及留居性物种（如野火鸡Meleagris gallopavo）。仅鉴定出血变形虫属（Haemoproteus）、疟原虫属（Plasmodium）和住白细胞虫属（Leucocytozoon）三类血孢子虫。血变形虫属是最流行的血孢子虫类群（46/237），其次为疟原虫属（11/237）。此外，血变形虫属亦是最为持久的血孢子虫类群，为四种鸟类宿主中均检出的唯一寄生虫属。55%的野火鸡样本存在混合感染（co-infection），但未发现血孢子虫混合感染的属类与宿主物种间存在显著相关性。此外，受感染个体占比（感染流行率）以及血孢子虫载量（感染强度与丰度水平）与宿主年龄、性别等生物因素均无显著差异。不过，寄生虫聚集模式（即寄生虫在宿主间的分布特征）受宿主年龄影响：成年野火鸡与幼年哀鸽的血变形虫属聚集指数——普劳林差异指数D（Poulin’s index of discrepancy D）最高。本研究揭示了不同猎用鸟类间差异显著的感染模式与寄生虫聚集特征，并为上述鸟类的血孢子虫提供了基线数据——据我们所知，目前伊利诺伊州尚未公开发布此类物种的相关血孢子虫感染数据。最后，本研究所得的感染模式可用于景观或宿主物种的管理工作，以助力鸟类保护行动。