The general idea is to keep to a fairly regular feeding plan then grabbing 'spot check' tests at different times of the day in order to build up a picture of:
1. how a particular dose is doing, and whether it is safe.
2. how your kitty's BG may vary on a 'typical' cycle (inasmuch as any cycle can be typical).
Obviously food will affect BG during the cycle. One tries to catch the nadir for the cycle as best one can, but with free feeding that 'nadir' always has the potential to be food-influenced as can any reading for the curve (hence the recommendation to lift food 2 hours before measuring preshot BG).
When running a curve and completely free feeding, recording the amount of food and carb kcal value paints a fuller picture.
If you do want to get some idea of how food might be influencing BG levels, you could try running a food trial:
1. Give kitty a meal then leave him for about 2 hours without food (obviously only if kitty is in safe numbers!).
2. Test BG then feed a measured portion of food. Lift any food that kitty leaves behind.
3. Test at +1, +2, and +3 to see how kitty's insulin (and pancreas) handle the carb load.
4. Over a period of time, you could run a series of food trials at different times of day to give you a better picture of BG fluctuations and how the dose is likely to be working at different times of day and night. (You would need to make sure you use exactly the same food for each food trial.)
My two penn'orth.
Mogs
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