Tuesday, May 3, 2011

Heather Smith Thomas: Notes from Sky Range Ranch — Addictions in Livestock, Part One

Humans don’t have a monopoly on bad habits and addictions or destructive behavior. My husband and I joke about some of the things our cattle do; for instance, the calves that try to “commit suicide.” Young calves are curious and bold, just like human kids trying to check out their world and see what makes everything tick. Calves like to lick, chew, and taste everything — from dirt to hay twines and fence posts — and they often go around licking hair off the net wire fence where their mothers have rubbed. Curiosity is natural, but some of them take it to extremes and get into serious trouble, with hairballs in their stomachs or by plugging their digestive tracts with other things, such as dirt or a blockage caused by eating twine, plastic bags, or other junk.

Young calves are naturally curious and bold.

Every spring there are some individuals in our groups of calves who love to follow the feed truck, trying to smell the exhaust. If the truck is parked for a minute at the gate or left running while we're doing some task out in the field, these calves stand by the exhaust pipe trying to breathe in as much of the fumes as they can. We joke about these exhaust junkies, hoping they don't overdose on carbon monoxide, and we compare them to human addicts who harm themselves with their substance abuses. The calves, however, don't seem to continue their obsession as adults; we don't have any cows that chase after the feed truck trying to sniff exhaust, so we chalk it up to juvenile curiosity. But adult cattle sometimes have strange behaviors that fall into a category of obsessions that we generally think of as being reserved for humans.

Our old feed truck — that we've used for feeding cows for more than
30 years — is always an attraction for curious calves, and
some of them love to go behind it and sniff the exhaust.

People are not the only creatures with addictions, strange behavior, or compulsions. We tend to think humans are the only ones who become drug addicts, glue sniffers, alcoholics, chain smokers, and so on. But if you work with animals, you know that they also fall prey to addictions, obsessive or compulsive behavior, or strange “habits,” particularly when they are kept in an unnatural environment and stressed.
Those of us who raise horses and cattle and spend a lot of time in close contact with our animals have noticed that some individuals resort to unusual behavior under certain conditions. Confined animals, in particular, seem more prone to unnatural behavior. Domestic animals experience a number of problems (physical and emotional) that are never seen in their wild counterparts. Horses and cattle, for instance, are herd animals that roam freely under natural conditions, grazing and wandering, and taking part in the social interactions of the group. The stress of confinement or isolation from others of their kind can lead to behavioral changes.

Horses and cattle are herd animals that roam freely under natural
conditions, grazing and traveling together as a group,
with many social interactions.

In horses, for instance, the stress of being confined in a stall can lead to such problems as cribbing, weaving, head bobbing, stall walking, stall kicking, self-biting, and other repetitive actions called stereotypies. These are usually rhythmic or repeated actions. Other examples of stereotypical behavior include paw licking in confined dogs, cage pacing in zoo animals, feather plucking in caged birds, and so on. In horses repetitive actions have been termed “stable vices,” but this is not an appropriate term. Technically speaking, vices are undesirable behaviors such as biting or bucking that can generally be overcome or corrected through proper handling and training. By contrast stereotypies are obsessive/compulsive behaviors that are much more difficult to halt.

A confined horse that spends a lot of time standing at his
stall door or at the gate of his pen may start "weaving"
(shifting his weight back and forth from one foot to
the other) or head bobbing to relieve his boredom.

By definition a stereotypy is a ritualistic or repetitive behavior that serves no apparent purpose. Stereotypical behavior is seen in about 15 percent of domestic horses. The amount of time the horse spends in these activities varies greatly from horse to horse and may be random or associated with a cue, such as feeding time; many confined horses habitually paw or kick the stall walls at feeding time or become more intense in their cribbing or weaving activities. The repetitive action is a way they've found to cope with stress or anxiety. In most horses that start these behaviors, it quickly becomes an addiction. Many cribbers, for instance, will continue the habit even if they are removed from the stall and turned out to pasture, and a weaver may still do his ritualistic action or head bobbing by the pasture gate or whenever he is confined again — in a stall or a trailer, for instance.

A horse confined by himself in a corral or small pen may start
pacing the fences, then do it as a repetitive action when bored.

Stereotypies in cattle are generally not so obvious, since they are rarely confined as much as horses are. We usually don't put cattle into individual stalls or pens, and most cattle are not as hyper as horses; we don't see the same effects that are triggered by boredom in the confined horse. But if you've ever had cause to confine cattle in small spaces — as in a feedlot situation or as 4-H or show animals, or when they are confined in a small pen or pasture for calving or winter feeding — you may have noticed some abnormal behaviors. Cattle may stand for long periods of time pressing their noses or upper lips against a solid surface, for instance.

Stereotypical behavior in horses (repetitive movements) or nose pushing in cattle are actions that increase the release of certain chemicals (endorphins) in the body that make the animal feel good. These chemicals are morphinelike proteins (also called opioids) that suppress pain and create a pleasurable sensation. Horses seem to be relaxed and “spaced out” after a cribbing or weaving session. In horses that crib or weave, the constant repetitive activity triggers the endorphin release. Thus when a horse learns that his weaving motions or cribbing (which he began in response to the stress of confinement, as an outlet for pent-up energy and frustration) give him pleasure, he may keep up the habit even when he's not confined and stressed, because he gets his “fix” by going through these motions, and he craves the endorphins.
Cattle also readily learn how to tap into their own endorphin release when confined, as we discovered many years ago. . . . [to be continued]

Heather Smith Thomas raises horses and cattle on her family ranch in Salmon, Idaho. She writes for numerous horse magazines and is the author of several books on horses and cattle farming, including Storey’s Guide to Raising Horses, Storey's Guide to Training Horses, Stable Smarts, The Horse Conformation Handbook, Your Calf, Getting Started with Beef and Dairy Cattle, Storey's Guide to Raising Beef Cattle, Essential Guide to Calving, and The Cattle Health Handbook. You can read all her Notes from Sky Range Ranch posts here.

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