While British cattle are larger and heavier than their counterparts in India and other Asian countries, they do not seem to be particularly intelligent, as we see here. Wandering onto a track which is a main route with rated speeds of 225 Km/h is not very smart. Anyway, see this news item from Peterborough in eastern England which refers to an accident on 2 Oct 2016:
Sometimes the cows win, as we see from this accident in 1984 in Scotland where a single cow caused a push-pull diesel express to derail with the death of over a dozen humans:
A picture of the accident site:
As you can see from the above Wikipedia article, this was a significant accident in that it brought out the dangers of push-pull trains with the loco at the rear running into an obstruction. If the loco had been in front the accident and number of casualties would not have been so serious.
India has had its share of relatively minor accidents involving cattle and camels, which have caused some derailments but without major damage or casualties. However, unlike the British railways, IR does have a significant number of larger animals such as lions, tigers and elephants.
Tigers and lions do get run over quite often. The relatively small number of lions in the Gir forest may be able to cope with the slow metre gauge trains in their area. But overcrowding has caused them to disperse to areas further away which have heavy broad gauge goods traffic, notably the line to Pipavav port. The results are predictable.
Elephants have caused accidents in several parts of the country, notably in North Bengal and Assam. The worst such accident was in Jalpaiguri district in 2013 which led to deaths of 7 elephants and injuries to several several others: https://en.wikipedia.org/wiki/2013_Chapramari_Forest_train_accident
No humans were affected in this accident.
However, this accident in 2000 near Dehradun did cause some injuries to humans:
May 2, 2000
18 injured as 3010 Dn Dehradun-Howrah Doon Express derailed after hitting a herd of elephants at unmanned crossing between Raiwala and Motichur (near the latter) on Dehradun-Haridwar section. The engine and 3 coaches were derailed. An elephant was killed.