The name is 'hurdle' not 'hurtle' ... unless that's the US version of misspelling English like colour/color, favour/favor, etc!
In athletics (track and field) there's events involving hurdles - they run and jump over them. Some horse races also include ones made from hedges, equestrian events too.
They're a common way of making, usually, temporary pens in a larger field so animals can be grouped for whatever reason.
The common material these days are lightweight steel post and rails, though for bigger animals like cattle and camels they use heavy duty ones moved around by tractors, etc.
If you search images for 'dog herding trials' they typically show pens made from hurdles.
So, a property would normally have it's perimeter fence made from plain or barbed wire depending on the stock being kept, a few larger enclosures maybe also made from the same, but to 'draft' animals from a larger group - like rams from ewes - they may use a small pen made from hurdles.
So, yeah, these pens could be made from traditional materials, but would need to be robust to take the knocks of animals in a confined space.
They're only meant to be temporary enclosures so work can be done on animals - tagging, drenching, hoof maintenance, collection for trucking to market, etc.
The traditional ones do look pretty though.