Quantity One is okay, you can have a try.

Seconding the ImageJ suggestion.

I intend to observe hepatic steatosis and fat diposition in placebo with the treatment groups.

Perhaps you can try Image J, plugin Color histogram.

I agree with All people. We used imageJ succesfully many times, You can see in our last papers a few examples:

https://www.researchgate.net/publication/284188169_Thermal_plasticity_of_body_size_and_cell_size_in_snails_from_two_subspecies_of_Cornu_aspersum

https://www.researchgate.net/publication/280882849_Automated_measurement_of_ommatidia_in_the_compound_eyes_of_beetles

https://www.researchgate.net/publication/281032552_Macro_S1_-_Automated_measurement_of_ommatidia_in_the_compound_eyes_of_beetles

https://www.researchgate.net/publication/267983913_The_Temperature-Size_Rule_in_Lecane_inermis_Rotifera_is_adaptive_and_driven_by_nuclei_size_adjustment_to_temperature_and_oxygen_combinations

Additionally, I can recommend you also CellSens (Olympus) and Nis Elements (Nikon) but these softwares are payable.

Good luck, Ania

Article Thermal plasticity of body size and cell size in snails from...

Article Automated measurement of ommatidia in the compound eyes of beetles

Data Macro S1 - Automated measurement of ommatidia in the compoun...

Article The Temperature–Size Rule in Lecane inermis (Rotifera) is ad...

Thanks a lot everyone for sharing such valuable information.

imageJ is the most oftenly used  free software.

Image J Cell Counter

Image tool or J. Both have counter cell.

You can use Image J. Either automated or manually depending on how accurate you need your data to be