I have found website that says the cattle cars were about a third of the size of an American railroad car. Check it out here http://www.ushmm.org/museum/exhibit/online/phistories/phi_deportations_journey_uu.htm
If this answers your question, then please press ACCEPT so I get paid for my work.
I will opt out of this question since I do not have any more information. But if I can find anything relevant I will get back to you.
Have a nice day,