She's mad about men and animals (6)
I believe the answer is:
horses
'animals' is the definition.
(I have seen 'Domesticated animals' mean 'horses' so perhaps 'animals' could also mean 'horses')
'she's mad about men' is the wordplay.
'mad' is an anagram indicator.
'about' means one lot of letters goes inside another.
'men' becomes 'OR' (Other Ranks: non-commissioned soldiers).
'shes' anagrammed gives 'hses'.
'hses' enclosing 'or' is 'HORSES'.
'and' is the link.
(Other definitions for horses that I've seen before include "Hoofed mammals (which go with 19 4)" , "''If wishes were . . . . . ., beggars would ride''" , "See 1" , "Domesticated animals" , "Equine animals" .)