It is terrible that animals die, because they do not understand what is happening and you can not explain to them how to survive properly. I once, a long time ago, was in the circle of "young naturalists" at the zoo. The minister told us that in winter the ungulates should have a bed of straw and water to drink (not everyone knows how to eat snow), and then they normally tolerate the cold.
In Ukraine, and it is quite cold there, there is an Ascania farm, where some antelopes are kept in the open air. For example, white-tailed wildebeest grow undercoat. But eland antelopes have no undercoat, they are cold, they are kept in an aviary in winter at a temperature of not less than +5C.
How many days will it be in Texas? It looks impressive.
The strange thing is that it's not very hot in the Southern Hemisphere right now, judging by the climate map, and it's the middle of summer there.