hair render in 2.79

im quite new here and i got a problem after update 2.79. I made some horses standing in grass, before update 2.79 there was no problem but after this program update it wont render any hair or grass or even show anymore (in the object view). I double checked everything like vertex groups etc. but all seems fine to me. is there something i might forget to check?

for now I switched back to 2.78 and its all good but I would like to get started with the new 2.79 :slight_smile: