Un humor de perros? Gatos?
I came across the saying "un humor de perros" and it was translated as---
A bad mood?
If I remember correctly, every dog I have ever had since I was a boy was friendly and happy all the time. Shouldn't this be ------ Un humor de gatos----?
11 Answers
This is a very good observation. This also reminds me of the expression "going to the dogs". I found this definition:
go to the dogs To go to ruin; degenerate.
It seems like dogs are getting a bad rap. Think of expressions using the word cat like "You look like the cat's meow." or "cool cat".
If I remember correctly, every dog I have ever had since I was a boy was friendly and happy all the time. Shouldn't this be ------ Un humor de gatos----?
Seriously, has anyone ever seen a "happy" cat? 
Who do you think this cat belongs to? 
However,
Q From Tom Halsted: Everyone knows that going to the dogs means going to rack and ruin or becoming worthless. But what exactly did go to the dogs to get the expression started? A In my callow and uninformed youth I used to think this referred to a visit to a greyhound racing track (usually called the dogs in Britain) and the consequent adverse effect on one’s wallet through betting on animals with no skill in chasing imitation hares. I now know better, though lots of humorists have had the same thought:
More dogged word play ... Greyhound racing in the UK appears to be going to the dogs according to the latest figures. Daily Telegraph, 16 Nov. 2009. The first known use of this jokey reference was in the Daily Mail in July 1927. It’s time it was retired.
The idiom is actually among the oldest in the language. There are references to bequeathing various useless things to dogs as long ago as the early sixteenth century. It was later borrowed by the Bard: Doctor: Therein the patient / Must minister to himself. Macbeth: Throw physic to the dogs, I’ll none of it. Macbeth, by William Shakespeare, 1605.
These and earlier examples — all suggesting throwing something to the dogs rather than going to them — evoke the famously unsanitary meals of the English medieval period, in which dogs were often present and were thrown scraps from the table. But the idea that anything appropriate for throwing to the dogs is useless goes back a lot further, as is illustrated by various passages in the Old Testament: And ye shall be holy men unto me: neither shall ye eat any flesh that is torn of beasts in the field; ye shall cast it to the dogs. Exodus 22:31 in the King James translation of 1611.
The sense shifted later to something that had been thrown away, hence ruined or destroyed. The idea of deterioration to a shocking extent, going to the dogs, came along rather later.
I love dogs and cats but I have to admit cats can be grumpy. On the other hand one of my favorite sounds is the purring of a cuddly kitty.
What about being sick as a dog and dog-tired?
And now we have Dog Day Afternoon, where everything goes to hell in a hand basket during the length of one afternoon.
Here is a retraction from my earlier statement. Although I must admit, our cat is still miserable and needs a real attitude adjustment! 
Cats are never in a bad mood, either!
Dog day afternoon refers to the hot days towards from the middle of July to the end of August when the dog constellation Sirius appears in the northern hemisphere horizon. People also talk about the dog days of summer.
I once had a neighbor who kept a sweet-natured beagle pup that had been bred and trained to be a bird dog. The neighbor insisted that the dog not be petted or treated in any way like a pet.
When I am in a bad mood, my friend calls me dragon lady.
Cuando esté de mal humor mi amiga me dijo "el humor del dragón" o la mujer de dragón.
Yes, I have seen happy, purring cats.
Maybe humor de perros was said of watch dogs. Going to the dogs refers to how dogs have often been treated. Like dogs.
