As for determining which animals have been strangled and not drained of their blood, we must understand that the focus was on the quantity of blood remaining in the meat of the animal. It was not the fact that the animal was strangled that kept it from being eaten, but the fact that it was never drained of its blood.
The Eocene constitutes the middle part of the Paleogene period (65-23 million years ago), preceded by the Paleocene and succeeded by the Oligocene epoch (34-23 million years ago); all of these periods and epochs were part of the Cenozoic Era (65 million years ago to the present).
Ludi Saeculares, secular games - the centennial rites and games of ancient Rome that marked the commencement of a new generation (100 years representing the longest life in a generation); observances may have begun as early as the 5th century BC and lasted well into the Christian era.