**A cargo train **
For cattle?
A few images of the “La Bestia” and the cargo
https://www.google.com/search?q=la+bestia&source=lnms&tbm=isch&sa=X&ei=e8y-U82KKJGcyASd_IH4BQ&sqi=2&ved=0CAcQ_AUoAg&biw=945&bih=656#q=la+bestia+train&tbm=isch