Goats are having a moment, and we're not just saying that because our blog is called Goats and Soda.

There are nearly 900 million goats in the world today, up from 600 million in 1990. The reason for this goat spurt is the growing popularity of goat cheese, goat milk and goat meat.

For goat farmers to do a good job, they need to understand their goats. And that's where Alan McElligott comes in. He's a senior lecturer in animal behavior at the Queen Mary University of London. And he says that goats are "underrepresented" in animal welfare studies.

That's bad for goat farmers. They need to know whether their herd is in a "positive" or "negative" frame of mind, he says: "If animals have chronic stress, they're far more likely to get ill. That costs money in terms of medicine and vet bills."

And it's not enough to know when your goat's mad. "Keeping animals is not just preventing them from being in negative states," McElligott explains. "You would want to have animals in positive states. But it is more difficult to identify those positive states."

So McElligott and several colleagues ran a study to see if they could find helpful clues for farmers. The research was conducted over summer months because "goats hate cold weather and particularly hate rain," so they're more cooperative subjects in warm weather.

We were definitely curious: What does a happy goat look like? We spoke to McElligott to find out.

Can you describe the experiments?

The key aspect is putting goats into what we consider mildly positive or negative situations.

To create a positive state, we use what we call food anticipation. We shake some food in a bucket a few seconds before we walk toward the goat and feed it. The animal feels a bit like how you feel when somebody is bringing you your dinner. You sort of perk up, creating a mildly positive state.

For the negative states, the experiments are really short. In one of the negative conditions, we put two goats in adjacent pens. Then we bring food to one of them, but not the other. The goat next door just watches the other goat eating for five minutes. During these experiments, we filmed the goats to see what their behavior was and had a microphone record them.

What are the signs of a gleeful goat?

A key parameter was the way the goats point their ears. They're more likely to point forward in a positive state rather than negative state. And the pitch in their call was more stable in the positive state; it didn't go up and down as much as in the negative states.

Were the goats fun to work with?

It's great to be around them. They're very curious. They're always investigating anything new in their environment by smelling and looking.

And they're very sociable. If you sit and watch a group of goats interacting, there's always lots of stuff going on, calling to one another, sniffing each other, laying down and touching one another. They also fight.

How does that compare to, say, sheep?

Many people assume goats are just the same as sheep. But people who've carried out research on sheep and goats say that goats are always exploring and going off on their own. Sheep behave like the stereotypical view of sheep.

The other thing I know from farmers who farm goats is that they need special, extra-robust fencing because goats are very good at getting out. They seem to be quite clever overall. And they've got long-term memory as well. Research two years ago showed that mother goats remember the calls of their kids for at least a year after those kids had been separated from the mothers. The mothers reacted more strongly to the recorded calls of their own kids than to calls from other kids.

Goats are so great. I would feel guilty eating goat meat. Do you eat goat meat?

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