No - never on cattle trucks. Originally they were open roofed until Board of Trade regulations made railway companies cover them some time after 1900. (Didn't stop the T & D using open ones until the end, though!).
The vehicles with the "part-tarpaulin" roofs divided roughly into thirds, with the middle section open, were otherwise normal goods vans. Officially "Convertible Vans", they were more normally known as "soft tops" because while they could be used as cattle vans with the tops open, they were more normally used for general goods with the open sections covered by tarpaulins, which were held down by ropes going over the sides and secured either side of the central van doors. Virtually all Irish railways had them, both standard and narrow gauge. None survive.
The last ones in traffic on the 5ft 3 were probably mid to late 50s, as once the "H" vans started to be built en masse, they disappeared, just as the energetic prodiction line of Park Royals and laminates sent the passenger six wheelers to the scrap man in pretty short order. I think that the West Clare and C & L may have had them almost until closure.
I believe that "soft tops" were a uniquely Irish idea.