Hello, I am looking at unanswered queries and have searched for your ancestor, there are about 8 Michael Donoghue / Donahue etc born iin Cavan around this time but none with these parents nor any other child either (remember I am using church reocords and there are gaps in some parishes or they start late)
I spread the search countrywide and discovered be searching an Ann born to these parents in Annagh parish in Mayo (Ballyhaunis Area) now there may be a mistake here as there is an Annagh parish in Cavan also. See here https://registers.nli.ie/
Records for baptisms in the Mayo parish only commence in 1851. Annagh in Cavan has baptisms for this period however the neighbouring parish of Castetara has no record for the periods in question.
Sorry I cannot do any better but you might try some of the county private genealogy Facebook groups who may be researching the same families etc
Good Luck
Pat