plants that poisons the milk

Pat Coleby lists in the sheep book some plants that poison the milk, for example privet. I feed privet in winter sometimes. What does that mean? Does it mean it poisons the milk for lambs or does it poison the milk for humans?
I didn't realize that it poisons us so far though.

I do not know but this seems to be pretty informative.  I have heard that privet is poisonous to sheep though.

http://docs.google.com/viewer?a=v&q=cache:o8RNjuWvp14J:www.dpiw.tas.gov.au/inter.nsf/Attachments/LBUN-7XU73N/%24FILE/Sheepfeed.mlc.pdf+Is+Privet+poisonous+to+sheeps+milk&hl=en&gl=us&pid=bl&srcid=ADGEEShnirAxwaNQwEU5y1mXvtQkTEAeP7TDGD6X3mrUeAXoZ70NtFr38knpbBDR-6EM3Bs_fRvERugyb7HYg9STGOhRmb_EC42-6nKGm12RwcU_jHCfRfKYdcx2rJdLmO58hLsv6m6j&sig=AHIEtbRmZUQEywgTcpUll7vs15N9F9AKUw

I fed my sheep tons of privet last winter and they were very healthy. Japanese honeysuckle I fed too, I just watched what they eat. Now I have a Friesian milker. and she does not touch Rhododendron.

Like I said, I have no clue having very limited experience with sheep.