Expert advice desperately needed

[Ken]

I'm a scientist with extremely limited ultrasound experience. We have a very old and tired ATL Ultramark UM9, which we used successfully to image heart function in sheep, the sheep heart being similar in size to humans. We are now transferring our research to mice, and are completely unable to capture an image on the UM9 with the existing transducers (1 is 5MHz, the other 4). We do have the services of a competent echocardiographer. We are advised that we need a higher frequency transducer to stand a chance of imaging mouse heart. Does anyone know what transducer I could install on the UM9, and would it work with the on-board cardiac package, and would it need new software? We don't have much money to spend, but if anyone could recommend an inexpensive, used portable ultrasound machine that would do the job, that might help. Thanking you all in anticipation.
:confused:

[Jed]

With the UM9 the highest frequency transducers 5MHz. I believe that you will need something in the frequency of 7 to 10MHZ, I do not think that the UM9 will work for scanning a mice heart.