Final answer:
Determining if a calf has nursed involves observing behavioral signs, checking for physical evidence such as milk on the muzzle, monitoring weight, and noting changes in the mother's udder size.
Step-by-step explanation:
Methods of determining if the calf has nursed or not can be key indicators of the calf's well-being and the establishment of a successful nursing relationship with the mother cow. Observing behavioral signs is a primary method; for example, checking if the calf shows signs of satiety and contentment after being near the mother, inspecting for the presence of milk on the calf's muzzle, or observing the calf's energy levels. Some more clinical methods can include monitoring the calf's weight to ensure consistent and healthy growth, checking for a full or distended abdomen indicating milk consumption, and paying attention to the calf's stool, as well-formed feces typically follow successful nursing. Furthermore, there should be observable physical changes in the mother cow, such as reduced udder size and possibly some leaking, which would indicate a recent nursing session.