The most common and most likely answer to this crossword clue is the 7 letter word SCRAPIE
I've seen this crossword clue in The Guardian
S
C
R
A
P
I
E
More clues leading to the result SCRAPIE
- Dump that is engendering beastly disease
- Waste material that is in beastly disorder
- Disease of sheep that is found by ditch
- Particle that is showing disease in sheep
- Sickness of sheep that is seen after fight
- Tricky situation – I caught a beastly disease
- It could give sheep a real itch, with regular scratching
- Rubbish pastry, papa’s common complaint
Buddy explains!

The straight part
We know that "beastly disorder" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case beastly disorder = scrapie.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does SCRAPIE mean?
SCRAPIE noun- A degenerative prion disease of sheep and goats that attacks the central nervous system.