One of the post grads students asked this ,
“… in the anatomy reading there is mention of white and dark muscle and that there are differences in drug distribution and that clinicians should be aware of this when administering medications. But there is no information of what the differences are. What is it that we should know about where we should be administering which drugs when giving IM injections?”
The dark muscle is probably more active/vascular so probably has faster uptake, right?
True, however, most fish have little dark muscle.
Their dark muscle is located as a narrow, superficial strip, subjacent to, amd running along the lateral line system.
The lateral line system is highly innervated.
The superficial lateral location of muscle also means maximum movement.
I would say these are reasons why we don’t really administer drugs there. We normally give into the large dorsal muscle bulk, close to the dorsal fin .