Horse collar

A horse collar is a part of a horse harness that is used to distribute the load around a horse's neck and shoulders when pulling a wagon or plough. The collar often supports and pads a pair of curved metal or wooden pieces, called hames, to which the traces of the harness are attached. The collar allows the horse to use its full strength when pulling, essentially enabling the animal to push forward with its hindquarters into the collar. If wearing a yoke or a breastcollar, the horse had to pull with its less-powerful shoulders. The collar had another advantage over the yoke as it reduced pressure on the horse's windpipe.

From the time of the invention of the horse collar, horses became more valuable for plowing and pulling. When the horse was harnessed in the collar, the horse could apply 50% more power to a task in a given time period than could an ox, due to the horse's greater speed. Additionally, horses generally have greater endurance than oxen, and thus can work more hours each day. The importance and value of horses as a resource for improving agricultural production increased accordingly.

The horse collar was very important to the development of many areas of the world. Wherever oxen were used and could be replaced with horses, the use of horses boosted economies, and reduced reliance on subsistence farming. This allowed people more free time to take on specialized activities, and consequently to the development of early industry, education, and the arts in the rise of market-based towns.

A horse collar is oval rather than circular and it is by design not very flexible. It is a padded appliance that conforms well to the shape of the horse's body. It is constructed so that at all points of contact with the body of the horse it avoids the air passage. By protecting the airway of the horse it became possible for the animal to use its full force to pull a load.

Long before the horse collar harness, there was the less efficient throat-girth harness. This, it was claimed, could be found in many ancient civilizations, according to early 20th century French cavalry officer Lefebvre des Noëttes. This type of collar was supposedly used in ancient Chaldea (3rd millennium BC), both Sumeria and Assyria (1400 BC–800 BC), ancient Egypt during the New Kingdom (1570 BC–1070 BC), Shang Dynasty China (1600 BC–1050 BC), Minoan Crete (2700 BC–1450 BC), Classical Greece (550 BC–323 BC), and ancient Rome (510 BC–476 AD). With this "ancient harness," ploughs and carts were pulled using harnesses that had flat straps across the neck and chest of the animal, with the load attached at the top of the collar, above the neck, in a manner similar to a yoke. These straps pressed against the horse's sterno-cephalicus muscle and trachea which restricted its breathing and reducing the pulling power of the horse. Thus, the harder a horse pulled, the more strongly it choked off its own breathing. Because of these supposed physical constraints, oxen were used in preference to horses for heavy work, as they do not have this problem due to anatomical differences and could be yoked to their loads.

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