Help with what statistical tests to use when comparing the effect of a drug on the growth of larvae

Hi - I am an undergraduate student looking for advice regarding statistical tests to use in my final year project. I’m trying to compare the growth rate of larvae that have been fed on different concentrations of a drug. There will be five different concentrations and also 2 controls. There will be approximately 50 maggots in each dish. I will be recording weights at 24 hour intervals. Since the maggots are so tiny, rather than weighing them individually I will be taking 25 each time, weighing them together and dividing by 25 to get a mean weight. That will give a table of results that looks something like this:

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At each time interval, I want to determine whether there is a statistically significant difference between the weights of the maggots fed on each concentration. I initially thought of using a one way ANOVA followed by post hoc tests but the problem is that I will only have a mean weight for each sample since I am weighing all 25 together each time (I won’t have individual weights). Is there any other sort of analysis I should be using? Should I maybe be doing some sort of analysis of the growth curves rather than a statistical test at each time interval?

Thanks in advance for any replies.


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