What steps are taken to ensure those animals are fed adequately? When dealing with larger populations of animals, how is it ensured that all of those animals received food during a certain time period, and not fed multiple times by different people working different shifts? Is there a procedure in place for identifying and treating animals with over and under nutrition?
I volunteered for 3 years at a large mammal laboratory where we diligently tracked the weight and caloric intake of each of our animals. Diets were weighed out each morning and total calories could be calculated based on the known caloric value of the particular food item.
We fed our animals during training sessions and would adjust the individual's food intake based on their appetite/motivation (i.e. if an animal was full, they'd drop the piece of food they earned or leave the session). This would indicate that we could decrease the individual's diet in small increments.
The animals were also weighed each week. Weight and caloric intake were recorded in daily logs using FileMaker Pro. This allowed us to view fluctuations of each throughout the year and compare to previous years. If an animal's weight was a bit lower at a certain time of year than it typically was in past years, we could increase their diet.
Diet items were selected based off of the animals' natural diet.
In our university, this is regulated by Institutional Animal Care and Use Committee
This organization provides guidance for humane and responsible management of laboratory animals. These protocols were established, and still modified, to enable optimal well-being of animals, as researchers extremely interested in robust and stable conditions for their subjects.
On the practical note, (we work with fish) we monitor such parameters as: - efficiency of laying eggs - average size and time to adulthood (sexual maturity) - life span - rate of malformation or illnesses
The food is monitored and regulated to make these optimal, but we change these things gradually, and usually use some smaller population to test changes, before applying to whole colony.