[1] Univ Sheffield, Dept Anim & Plant Sci, Sheffield S10 2TN, S Yorkshire, England
[2] Princeton Univ, Dept Ecol & Evolut Biol, Princeton, NJ 08544 USA
[3] Univ Edinburgh, Ashworth Labs, Sch Biol Sci, Ctr Infect Dis, Edinburgh, Midlothian, Scotland
[4] McMaster Univ, Dept Biol, Hamilton, ON, Canada
[5] Serengeti Dist Livestock Off, Minist Water & Livestock Dev, Mugumu, Tanzania
[6] Univ Edinburgh, Sch Vet Studies, Roslin Inst Royal Dick, Div Infect Immun, Roslin, Midlothian, Scotland