﻿ Nursing baby

## Milk Production

Nursing Babies

• From the viewpoint of a calf, each calf gets a percentage of their diet from milk according to the following curve based on age:
• First a calf determines how much mass it wants to eat, the Satiation Mass, SM, using the equations described below. Then, using the % of diet from milk curve, we calculate how much mass comes from milk. The remainder would have to be made up from food. For example, if a 60 day old whale wants to eat 15 kg, then 98% would come from milk or 14.7 kg from milk, and the remaining .3 kg it wants would have to come from prey.

Lactation

• The amount of energy a calf gets from milk is: 3.69 kcals/gram. This is multiplied by a digestion efficiency of 0.95, meaning most milk a calf eats gets converted to usable energy.
• From the viewpoint of the mother, it requires additional energy to produce milk. We model this by increasing its FMR by the amount of energy produced by its milk. The mother's FMR must be calculated AFTER the energy consumed via milk for the calf is calculated. For example, if the calf is eating 50000 kcals worth of milk, then the FMR for the mother is simply increased by 50000 kcals divided by an efficiency of 0.75, i.e. it takes a little extra energy to produce the 50000 kcals of milk.
• For a nursing mom that is losing weight, decrease milk production linearly from 100% to 0% as mom's mass goes from 85% to 75% of ideal.