Final regulations to implement ACA provisions, issued in 2013 by the US Department of Labor (DOL), said health-contingent wellness programs can vary group health plan premiums or cost sharing based on health status and will not be considered to discriminate based on health status if they meet five standards.
It's only a partial answer, but a Nile crocodile can eat up to half its body weight at a sitting, according to National Geographic. Since few freshwater fish weigh half as much as a crocodile, we can probably assume these croc feasts occur when they're able to ambush ungulates (e.g. zebras and antelope).
The Feeding Habit. The feeding habit of zebras is a bit complex. Zebras are basically herbivores. They eat plain grass, shrubs, herbs, twigs, leaves, roots and bark from trees. Grass is the basic diet of mountain and plain zebras. It forms about 92% of their overall diets. They eat red grass, Bermuda grass that they find along the riverbeds and short grasses like common finger. Zebras also eat herbs and shrubs which constitute about 5% and 2% of their diet plan respectively.