Serial blood cell counts of gray collie before and after treatment with rG-CSF and lentivirus. After confirming that neutrophil counts were cycling we administered recombinant canine G-CSF at 1.5 μg per kg per day (day 71). On day 131, G-CSF administration was stopped and 10⁹ IUs of lentivirus encoding canine G-CSF was injected intramuscularly. Shown are absolute neutrophil counts (A), lymphocytes (B), and monocytes (C).