Early signals of parasitism expressed through behaviour but modulated by social context

Sickness behaviours are believed to be an adaptive response infection. However, the degree which these can expressed may impacted by individual's social environment. Here we tested, first, whether parasitism reduces activity behaviour of lambs, Ovis aries , second, this occurs prior other observed costs and, third, infection status individuals affects expressed. Sixty lambs were separated into replicate groups within three treatments: (1) parasitized: all infected with parasitic nematode Teladorsagia circumcincta ; (2) nonparasitized; dosed water; (3) mixed: some group and water. Activity was monitored before, during after parasite Parasitized had reduced levels following infection, occurred before any impact or measure detected. Infected animals in mixed but level change less than that fully parasitized groups. remained low until treated anthelmintic when been returned same as nonparasitized These findings show parasite-induced behavioural changes occur earlier more commonly signals profile shape responses • Domestic experimentally a gastrointestinal nematode. This affected status. Thus, environment affect their