In the last issue we discussed stress and some of the effects noted under different situations where environment and nutrient availability created stressful situations for cattle. As mentioned, in most cases stress is counter productive and reduces performance (i.e. reduces gains, feed efficiency, reproductive performance, immune response). In addition to environment and nutrition, two of the most common animal stressors include handling and transportation. We will focus on these areas in this issue. Much of the work done on handling and transportation stress has been led by Dr. Temple Grandin at Colorado State University. She is considered by many to be the leading researcher in this area and has devoted her career to researching and developing systems that will reduce stress and improve handling of animals during processing, transportation, slaughter, etc.
The stress of handling and transportation is largely induced by fear. Fear is a very strong stressor, and is basically a psychological stress or stress from how animals see, perceive, feel in a given situation. Some examples are restraint, contact with people, or exposure to novelty (something they are not accustomed to). The responses seen and measured in animals have been very closely correlated to the responses to fear seen in humans. In cattle, previous experience and genetic factors affecting temperament will work together in complex ways to determine how fearful an animal may become when it is handled or transported. The genetic factors are related to observations that certain breed types seem more excitable than others. Cattle trained and accustomed to a squeeze chute for instance, may be fairly calm, whereas cattle unaccustomed to such handling may be highly fearful and therefore experience a high level of stress in the same squeeze chute. The squeeze chute is perceived as neutral and non-threatening to one animal; to another animal, the novelty of it may trigger intense fear. Novelty is a strong stressor when an animal is suddenly confronted with it.
Procedures such as restraint in a squeeze chute do not usually cause significant pain, but fear may be a major psychological stressor in cattle unaccustomed to the handling. Fear responses in a particular situation are difficult to predict because they depend on how the animal perceives the handling or transport experience. The animal's reactions will be affected by a complex interaction of genetic factors and previous experiences. For example, animals with previous experiences with rough handling will remember it and may become more stressed when handled in the future than animals that have had previous experiences with gentle handling. Previous handling experiences may interact with genetic factors. Rough handling may be more detrimental and stressful to animals with an excitable temperament compared to animals with a calmer temperament. For example, a study in 1992 showed that Brahman cross cattle had higher cortisol levels when restrained in a squeeze chute than English crosses. One of the most commonly used indicators of fear response in research is the measurement of cortisol levels. Cortisol is a hormone which has been shown to be highly affected by various stress effects. In other words, when an animal is stressed, cortisol levels increase.
So what does this tell us. To begin with, handling of cattle should be done in a calm, quiet manner. Yelling and screaming, hitting with sticks or cattle prods will create a bad experience for the animal and each subsequent processing or handling will be worse. This is especially true in animals that may or may not have been handled in a processing facility before. In addition to the new surroundings (i.e. crowding tubs, alleys, squeeze chutes, etc., noise has a particularly negative effect of stress levels. Additionally, administration of pain from hitting or shocking has a similarly negative effect. Especially in breeding cattle where they will very likely be brought to the facility again, it is extremely important to minimize the stressful factors.
What are some of the steps that can be taken to reduce stress of handling? Let's take a look at several that are especially useful in breeding animals:
1) Make sure that facilities are designed as well as possible to smooth facilitate movement of cattle. Many different sets of plans are available for all types of operations to help with improving the ease of handling that can be used as a reference. Draw a basic diagram of your processing/loadout facility. Begin by eliminating the square corners. These are always areas where cattle will crowd up and can injure one another. Also, if possible, the sides of the concentration area (tub), and the chute should be solid. This eliminates much of the outside visual “stimuli” that cattle receive during movement. Chutes should be curved if possible with solid sides to induce cattle to continue moving forward. Make sure chutes are not too wide or too narrow to prevent turn around of cattle getting stuck. The actual squeeze chute or head gate should be in good repair and solidly mounted or set. A lot of movement is stressful and dangerous for the animal AND the operators. The surface on which the cattle are walking needs to provide good traction. Smooth concrete is the absolute worst surface and can lead to extensive injuries in the animal. Concrete surfaces should be grooved/texturized to insure that solid footing is available.
2) Keep things as quiet as possible. If you have a hydraulic chute it is a good idea to locate the motor and pump away from the working area if at all possible to reduce the noise level. Also make sure that moving parts are lubricated to improve operation and reduce noise levels. Keep the amount of shouting at animals to a minimum. Also, if dogs are used for gathering, once cattle are at the facilities, dogs need to be penned away from the cattle to reduce barking as well as interference during the working process. Sit down with everyone involved in the handling process before hand to make sure everyone understands that calm, quiet handling is the goal.
3) If time permits on occasion, bring cattle up to the working facilities and move them through for acclimation purposes. This helps them get accustomed to the facilities so that they have an idea of what to expect the next time you bring them through for actual processing. This is especially important for cattle in a breeding program where artificial insemination or embryo transfer are used. Some breeders I work with will occasionally bring cattle in and feed or hay them in gathering areas for the same reason.
4) Spending time in and around cattle is also effective. This taming effect has been shown to reduce stress responses. Depending on your situation, cattle should be handled and approached the same when checking on them as when handling whether it be on foot, on horseback, by vehicle, etc. I remember receiving a group of cattle into the a research facility that I was working with that had come out of South Texas (lot of Brahman influence) that had been gathered with 6 men on horseback, 12 dogs and a helicopter. Needless to say, they were a little flighty when they got to us.
As mentioned above, reproductive performance in animals that have been heavily stressed by handling is often compromised. Facilities that are awkward or very noisy, too much shouting as well as poking and proding will reduce conception rates, increase services per conception and decrease the number of E. T. pregnancies. It is essential in an intensively managed breeding program such as this that special care is given in handling and stress management.
Any time you take an animal and stick it on a moving vehicle, it's going to cause some stress. In many cases, a lot of stress. Consider several scenarios here which are all related to transportation stress: 1) Cows are gathered and hauled from one pasture to another because you ran out of grazing; 2) Cattle are gathered and the calves are pulled off and taken to another local pasture, to the auction ring, to wheat pasture or a feedlot several hundred miles away; 3) You load your show heifers or steers and carry them to the local show or to one at the state or national level. Each of these situations creates a stressful situation for the animal which can result in shrink, reduced performance, sickness or even death. Of these ones listed, the lowest level of stress is probably measured in the show animals who are accustomed to being handled, are on a superior plane of nutrition and are typically kept cooler or warmer to begin with. The highest level of stress is associated with young cattle being weaned directly off the cow and heading for the sale barn. In addition to the handling stress initially at the farm or ranch, they are then transported a certain amount of miles, unloaded at a sale facility where they may remain 12 to 24 hours or more and may or may not receive feed, hay or water. Additionally, they are intermingled with other cattle who may be carrying any number of disease organisms to which these cattle may not have an immunity. After this they may be transported to an order buyer's facility where they are held for an additional period of time - this may be several days where they will probably receive hay and water. They may possibly be processed at this time to some degree. Finally, they are loaded on another truck and taken to pasture, a growing or preconditioning yard or to a feedlot. Needless to say, after this time and travel, these cattle are very stressed out and in a high health risk category.
Cattle that have gone through this chain of events will typically exhibit some of the following:
1) Significant levels of shrink. Shrink, under normal conditions is simply a loss of body liquids and digest through urination and defecation. Typical shrink during transportation can range from two to eight percent or possibly more. To put this in perspective, five percent shrink in a 500 lb. calf is equal to losing 25 lbs over a very short period of time. This would be the equivalent of a 200 lb. man losing 10 lbs over a day or two. Obviously not a healthy situation. In addition to losing significant amounts of nutrients, a lot of body liquid is lost, creating dehydration in the animal
2) Research has shown that through the course of transportation and marketing stress, a multitude of body nutrients (in addition to water) can be lost. These include minerals such as potassium, nitrogen, phosphorus, zinc and so on. Also, since rumen fill is decreased, rumen function is decreased as well, meaning the animal may not be able to process what feed or hay it eats (if it eats) when it gets off the truck. When minerals such as those listed are lost we see a decrease in muscle function, reduction in energy metabolism, reduced response by the immune system to infectious agents, etc. This is one of the reasons that after long distance shipping cattle can become sick so easily and die. It is imperative that stress be managed both before and after shipping.
One good way to minimize shipping stress is to wean cattle a period of time before shipment, perform the other desired processes at this time and keep the animal on a sound nutritional plane. This makes sure that body stores of the critical nutrients are optimal before shipping and that, while losses will still take place, the amount remaining will be significantly higher and will not pose as much of a problem once they reach the final destination.
Do not place cattle in a situation where they must be held in a pen off feed or water for any longer than necessary. This means gathering should be done quickly and trucks should be lined up to load as soon as cattle enter the pens. Subsequently, in cattle going to the sale barn, take them to the sale a late as possible before they stop receiving, this will help reduce some of the shrink in the auction facility as well as reduce the exposure to strange organisms. Additionally, cattle should not be on a truck any longer than necessary. Additionally, cattle should not be over crowded and surfaces on which they stand should be textured to provide a solid footing.
Upon receipt, cattle should be put in relatively small pens or traps with fresh, high quality hay and water as well as a complete, balanced receiving feed (preferably medicated with something like CTC) which includes adequate protein and energy, high levels of minerals and vitamins. Since rumen function will likely be depressed do not feed anything with urea or high fat levels (in excess of five percent. Pen should not be too large for fear of cattle getting lost in the pens and waterers and troughs should be positioned so cattle can find them easily. A practice that some producers are finding useful includes the positioning of a liquid feed tank where a molasses based liquid feed product (with NO urea) is available for the calves to eat for the added dry matter and sugar intake to stimulate bacterial activity and rumen function. Additionally, it may be useful to administer a probiotic at this time to assist with the function of the rumen.
Similar practices should be used with other cattle as they are transported.
There is no way to eliminate stress. We can, however, take major steps to reduce it's effect by using a little planning and some common sense. Remember that the more that you can reduce the various types of stress we have discussed the more productive your herd will be.
Dr. Steve Blezinger is a nutritional and management consultant with and office in Sulphur Springs, TX. He can be reached at P. O. Box 653, Sulphur Springs, TX 75483, by phone at (903) 885-7992 or by e-mail at firstname.lastname@example.org.