Vertebrate Pest Research Unit, New South Wales Department of Primary Industries, Orange, New South Wales, Australia.
School of Agriculture and Food Sciences, University of Queensland, Gatton, Queensland, Australia.
PLoS One. 2022 Jul 28;17(7):e0271272. doi: 10.1371/journal.pone.0271272. eCollection 2022.
Rabbit Haemorrhagic Disease Virus (RHDV), which is a calicivirus, is used as a biocontrol agent to suppress European wild rabbit populations in Australia. The transmission of RHDV can be influenced by social interactions of rabbits; however, there is a paucity of this knowledge about juvenile rabbits and the roles they may play in the transmission of RHDV. We aimed to quantify the social interactions of juvenile (< 900 g) and adult (> 1200 g) rabbits in a locally abundant population in the Central Tablelands of New South Wales, Australia. Twenty-six juvenile and 16 adult rabbits were fitted with VHF proximity loggers to monitor intra- and inter-group pairings. Use of multiple warrens by these rabbits was investigated using VHF base stations at nine warrens and on foot with a hand-held Yagi antenna. Juvenile rabbits were strongly interconnected with both juveniles and adults within and outside their warren of capture, and almost all juveniles were well-connected to other individuals within their own social group. Inter-group pairings were infrequent and fleeting between adults. Both juvenile and adult rabbits used multiple warrens. However, visits to warrens outside their warren of capture, particularly those within 50 m, were more common and longer in duration in juveniles than in adults. The high connectivity of juveniles within and between warrens in close proximity increases potential pathogen exchange between warrens. Therefore, juvenile rabbits could be of greater importance in lagovirus transmission than adult rabbits. The strength of juvenile rabbit inter- and intra-group pairings, and their tendency to use multiple warrens, highlight their potential to act as 'superspreaders' of both infection and immunity for lagoviruses and other pathogens with similar lifecycles. Confirmation of this potential is required through examination of disease progress and rabbit age-related immune responses during outbreaks.
兔出血症病毒（RHDV）是杯状病毒科的一员，被用作生物防治剂来抑制澳大利亚的欧洲野生兔种群。RHDV 的传播可能受到兔子社交互动的影响；然而，关于幼兔及其在 RHDV 传播中可能扮演的角色，我们对此知之甚少。我们的目的是量化澳大利亚新南威尔士州中部台地一个丰富的本地种群中幼兔（<900 克）和成年兔（>1200 克）的社交互动。我们给 26 只幼兔和 16 只成年兔佩戴了甚高频近距离记录器，以监测它们在组内和组间的配对情况。我们在九个兔窝和徒步使用手持八木天线的方式，利用甚高频基站调查了这些兔子对多个兔窝的使用情况。结果发现，幼兔与兔窝内外的幼兔和成年兔紧密相连，几乎所有的幼兔都与自己社会群体中的其他个体紧密相连。成年兔之间的组间配对很少见，且持续时间很短。幼兔和成年兔都使用多个兔窝。然而，与成年兔相比，幼兔更频繁且长时间地访问自己兔窝以外的兔窝，尤其是距离自己兔窝 50 米以内的兔窝。近距离内兔窝间幼兔的高连通性增加了兔窝间病原体的交换。因此，幼兔在拉格病毒传播中的作用可能比成年兔更大。幼兔在组内和组间的配对强度及其使用多个兔窝的倾向，突出了它们作为拉格病毒和其他具有相似生命周期的病原体的感染和免疫“超级传播者”的潜力。在疾病爆发期间，通过检查疾病进展和兔子年龄相关的免疫反应，需要对这种潜力进行确认。
