This depends on what you mean by 'rings'. Are they under the skin? Are they 'spots' like on an Appaloosa, or dapples? The rings could be anything and without further description there could be many answers to this question.
Men typically have narrow hips and less round buttocks. Women typically have wider hips and rounder, fuller (or thicker) buttocks.
Estrogen
They have strong muscles, big hips, large chest, and plenty of stamina and speed. Horses are very strong animals and have a large structures so be careful when you are hauling things with them.
Rose hips are round or oval-shaped berry-like fruit that typically range in color from red to orange. They are usually about the size of a cherry and have a fleshy outer layer surrounding small seeds inside.
Pivot joints in horses include their head and their hips. This joints allow them to rotate without endangering themselves in the process.
They have hips
Their bones naturally losing (some) strength.
When I was working at Tractor Supply Company, we sold Methylsulfonylmethane for horses. Methylsulfonylmethane is used to improve joint and hip conditions in horses. It acts as an anti inflammatory which could improve movement in the joints and hips for older horses or help with the longevity of a younger horses joints and hips. Typically, at TSC, we would get people who would come in that looked like they knew NOTHING about horses and would steal it off of our shelves until we locked it up in a class case. To answer your question, it was explained to me that Methylsulfonylmethane or MSM, when added to meth, it is used to cut meth. Cutting meth is used by dealers to get a larger yield from their product. It is a cheaper way for them to make a much larger profit.
Those spots are the hamster's scent glands. They won't 'go away', they are supposed to be there.
Rose hips are the small, round, berry-like fruits that develop on rose plants after the flowers have bloomed. They are typically red or orange in color and can be identified by their size, shape, and color. Look for them on the stems of the rose plant after the petals have fallen off.
Polymyalgia rheumatica is a syndrome that causes pain and stiffness in the hips and shoulders of people over the age of 50.
Horses move their hips when they move in a circle. They do this by using pivoting joints. The ability to turn easily prevents them from getting hurt.