Well, I'd like to have Kanami have at least a bit of interaction with the others, so the shock would hit them a lot harder. Also, I'd like to have Kanami at least get to know Raiga a bit beforehand, maybe make a few comments ("What a pretty dog.."), entirely innocent, of course. So, maybe she was around at the farm for a day at most without being exposed to the other experiments or she also arrives at that time.