Rajesh Kumar Singh / AP

An Indian villager collects cow dung cakes, after they are sun dried on the banks of the River Ganges in Allahabad, India. Cow dung cakes are a major source of domestic fuel for rural households and an environmentally-friendly alternative to firewood.

Matthias Schrader / AP

A young Bavarian herdswoman drives her beasts through the landscape during the return of the cattle from the summer pastures in the mountains near Bad Hindelang, southern Germany, on Sept. 11, 2012. At the end of the summer season, farmers move their herds down from the Alps to the winter pastures in the valley.

Matthias Schrader / AP

Herdsmen rest during the return of the cattle from the summer pastures.

Matthias Schrader / AP

A young herdswoman watches over the cattle.

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AP's Veronika Oleksyn reports from Laufen, Germany: When Regina Mayer's parents dashed her hopes of getting a horse, the resourceful 15-year-old didn't sit in her room and sulk. Instead, she turned to a cow called Luna to make her riding dreams come true.

Hours of training, and tons of treats, cajoling and caresses later, the results are impressive: not only do the two regularly go on long rides through the southern German countryside, they do jumps over a makeshift hurdle of beer crates and painted logs.

Kerstin Joensson / AP

Regina Mayer jumps with her cow Luna over a hurdle in Laufen, southern Germany, on March 29.

"She thinks she's a horse," the golden-haired Mayer joked on a recent sunny afternoon as she sat atop the impassive brown-and-white, grass-munching cow.

It all started about two years ago, shortly after Luna was born on the Mayers' sprawling farm in the hamlet of Laufen, just minutes from the Austrian border.

They started off with walks in the woods during which Luna wore a halter. Then Mayer slowly got her cow more accustomed to human contact and riding equipment.

About six months later, it was time to see how Luna would respond to a rider on her back. Mayer sat in the saddle, and all went as planned — at least at first.

"She was really well behaved and walked normally," said Mayer, decked out in riding gear. "But after a couple of meters, she wanted me to get off! You could see that she got a bit peeved."

Kerstin Joensson / AP

Regina Mayer gives her cow Luna a treat.

Luna and Mayer are now soul mates, spending most afternoons together once the teen — who aspires to become a nurse one day — comes home from school.

Their extensive routine involves grooming, petting, jumps and a roughly one-hour ride. That's also the case in winter, when Mayer lovingly drapes a blanket over Luna to keep her warm.

It's a lot of work "but I enjoy it," Mayer said.

Her efforts have paid off.

Now, Luna understands commands such as "go," "stand" and "gallop." If she feels like it, that is.

"When she wants to do something she does it, when she doesn't, she doesn't," said Mayer, who proudly says Luna thinks of her as her mother. "And she's often very headstrong but can also be really adorable."

Luna's stubborn streak meant that teaching her pony tricks wasn't always easy, Mayer noted, saying she sought tips from a cow expert in Switzerland on how to deal with "steering" problems.

Anne Wiltafsky, who trains cows near the Swiss city of Zurich, said Luna's talents are not particularly surprising and that, historically, it was quite common to ride cows and use them as workhorses.

"Especially younger ones can jump really well," Wiltafsky said in a telephone interview, adding that cows are lovable companions because they're easygoing, have strong nerves and are "unbelievably devoted" to people they like.

Kerstin Joensson / AP

Regina Mayer walks with her cow Luna.

Being — and owning — a cow-turned-pony isn't always easy.

Take the somewhat skeptical neighbors, such as Martin Putzhammer, who had to be won over.

"At first I thought it was kind of weird — a kid on a cow?" the 17-year-old said during a break from repairing his moped. "Had to get used to it but once I did I thought it was pretty funny."

While Mayer's friends quickly warmed to her passion after laughing at her, Luna's fellow cows weren't so open-minded.

"Cows don't really like her ... they're jealous because she always gets goodies," Mayer said.

And horses? Many run away in fright, but others often join Luna on rides.

"She really enjoys that and gets totally into it," Mayer said.

Mayer hasn't given up her hopes of having a horse and may soon get one. But she says Luna will always have a special place in her heart.

"She'll stay my darling," she said.

In many parts of the developing world, caked and dried cow dung is used as fuel. Dung may also be collected and used to produce biogas to generate electricity and heat. The gas is rich in methane and is used in rural areas of India/Pakistan and elsewhere to provide a renewable and stable source of electricity.

Ajay Verma / Reuters

A villager makes cow dung cakes used as cooking fuel at Maloya village on the outskirts of the northern Indian city of Chandigarh on January 31, 2011.

Ajay Verma / Reuters

A villager makes cow dung cakes used as cooking fuel at Maloya village on the outskirts of the northern Indian city of Chandigarh on January 31, 2011.