From The General and the Jaguar: Pershing’s Hunt for Pancho Villa: A True Story of Revolution and Revenge, by Eileen Welsome (Little, Brown, 2009), Kindle pp. 189-192:
The horses suffered the most. They were not the tough little ponies that the Villistas rode, but large-boned thoroughbreds or crosses between several breeds. They were big and powerful, but fragile, too. Nearly all of them were classified as “bays,” a stingy army description that failed to capture the many hues of a brown horse. In actuality, they were the color of ginger, cinnamon, and cloves; rich, warm chocolate, coffee, and the watery tannic of tea. Only their eyes were the same, huge dark pools revealing an animal capable of great fear and great courage.
Horses have a grazing animal’s nature; they are self-reliant and content enough to live alone, in the middle of a great plain, with only the wind and crows for company, but happier still with another horse that they can stand parallel to in the buggy months of summer, noses and rumps reversed, the tail of one swatting the flies from the face of the other. They are creatures of habit and thrive on the monotonous turning of day into night, looking forward to a pat of hay for breakfast, a pat of hay for lunch, a pat of hay for dinner, and grass in between. They become cantankerous when their feeding time is altered, startle at loud noises and sudden movement, and are made uneasy by changes in their environment. Yet these were precisely the travails that they would have to endure on the expedition.
Soldiers are expected to stand and fight, but everything in a horse tells it to flee when confronted with danger. Horses are gentle and unaggressive by nature, but their dispositions can turn rebellious in the hands of the wrong rider. Their mouths open willingly for the bit, which sits at the corners of their lips. If this most intimate of spaces is violated, if the reins are jerked or pulled repeatedly, horses can become tough mouthed and nonresponsive, or even worse, clamp the bit between their teeth and run away with their passenger. Their flesh is extremely sensitive—who has not seen a horse shudder under a fly’s weight?—yet ignorant riders think it necessary to pummel them with whips and spurs until the animal retreats into some reptilian corner of its brain and refuses to move at all.
A horse’s back—the beautiful curve that begins at the top of the head, slopes down across a smooth plain, and gently rises into the tail—must be carefully tended. Horses that experience pain and discomfort while being saddled learn to jig and prance and fill their bellies with air so that the girth strap needs to be repeatedly tightened. The long, twisting rivers of muscle covering the leg bones are susceptible to strains and microscopic tears, and an injury in one leg often means the other three have to compensate, with one injury frequently leading to a second. Even more impractical are a horse’s ankles, dainty as a ballerina’s and prone to wind puffs—swollen tissue that subsides only with rest and liniment.
The hooves, which are hard as stone, seem to be perfectly adapted to withstand the enormous impact of walking and trotting and cantering. At their center, though, is a wedge-shaped “frog” prone to drying and bruising. The wrong kind of food can flood the thick horny material with heat and cause permanent damage. Regular trimming and properly fitted shoes are essential. Unfortunately, the animals ridden into Mexico received neither, and their hooves grew long and added to their fatigue and the strain on their legs. The cavalrymen were considerate of their horses and tried to lessen their suffering. They brushed them twice a day and turned them loose to graze whenever possible. (The young Patton was adamant about the need for grazing and wrote scorching memos whenever he saw horses standing on the picket line.) But even the most tender, loving care could not make up for the lack of rolled oats and green alfalfa. The horses chewed up leather bridles, saddlebags, halters, and ropes. The soldiers purchased native corn, but before the grain could be fed to the horses, it had to be dumped onto blankets and the many small pebbles found in the mixture laboriously picked out. Starved though they were, many horses simply stopped eating if their teeth struck a rock. As the flesh melted from their bones, extra blankets were needed under the McClellan saddles to protect their backs. “Great care was taken of the horses’ backs,” remembered Sergeant Converse. “Blankets were folded carefully, saddles packed so the weights were distributed evenly and the men not allowed to lounge in the saddle.”
Many of the horses taken into Mexico were debilitated from the trauma of being boxed up and transported in railroad cars and they suffered from shipping fever and lice. During the campaign, they developed constipation, diarrhea, and life-threatening colic. Some fell to their deaths when they lost their footing on the mountain trails, or were dragged off a cliff by the wagon they were pulling. Many more were killed in the running gunfights, for they were always the largest targets on the battlefield. The majority, though, died of exhaustion and hunger. Quickly, like the little Villista ponies, they gave up their lives. A few were let go on the trail, to fend for themselves, but most were put out of their misery by a merciful bullet to the head. The soldiers grieved their deaths. Poor beasts, they muttered as they passed the huge, ungainly forms, bloated and barrel shaped, a blasphemy of the graceful creatures that they had been in life. With each one lost, Pershing’s challenge became greater. And the fighting had not yet begun.