Animal management deals with a wide variety of issues related to caring for domestic livestock including: economic, environmental, community aspects, feed supplementation, large animal nutrition needs.
Learn more about Feed Supplementation and Animal Diet and Behavior:
- Supplemental Feeding of Livestock on Rangelands
- Mineral Nutrients
- Experiences Early in Life Affect the Structure of the Body
- Palatability More Than a Matter of Taste
- Preparing Animals for Moving Day
- Behavior Depends on Consequences
- Mother Knows Best
- Role of Learning in Diet Preferences
- Learning About Foods and Locations
- Diet Mixing: Increasing Intake of Unpalatable Plants
- Training Animals to Avoid Foods
- Can Cows Eat Snow to Meet Water Requirements?
Written by Rachel Frost and Jeff Mosley, Montana State University
Under certain conditions, livestock grazing western rangelands are not able to consume enough nutrients from forage alone to meet their nutritional requirements. At these times, supplementary nutrients are often provided to maintain production levels. Supplementation is one of the biggest expenses of range livestock production, accounting for up to 70% of the operation's total variable expenses. Providing the proper supplements in the correct amount and at the appropriate time can save producers money and conserve forage resources.
Determining the proper supplementation program requires livestock managers to know the following:
- nutritional requirements of the grazing animal
- nutrient content of the forage
- cost of supplementation and expected benefits
The decision to provide a supplement should be based on forage supply, protein content, and animal body condition.
Basic Ruminant Nutrition
Ruminants differ from pigs and humans in their ability to digest fibrous plants because they have a rumen that allows for fermentation before the food enters the abomasum (stomach) of the animal. The rumen houses microorganisms that are capable of breaking down cellulose through fermentation. These microorganisms break down consumed feedstuffs for their own nutritional requirements and in return release volatile fatty acids that are a major energy source for ruminants. The microorganisms eventually die, and their bodies pass into the small intestine, where they are digested and contribute to the protein supply of the animal. This symbiotic relationship, while essential, also adds to the complexity of predicting and effectively meeting the nutrient requirements of ruminant animals.
Relationship of Protein and Energy within the Ruminant
Ruminants need the microorganisms to "unlock" the energy in forage, allowing them to harvest and make use of cellulose that is unavailable to non-ruminants. The existence and growth of microorganisms depends on an adequate supply of nitrogen, primarily found in protein. Supplementing ruminants with protein increases the number and activity of microorganisms in the rumen, which improves forage digestion and increases passage rate and intake of forages. Increasing forage intake improves energy availability; therefore, correcting a protein deficiency is generally the first supplementation priority.
Types of Protein Supplements
Escape protein does just what its name implies and escapes digestion in the rumen. It travels to the small intestine where it is broken down and used directly by the animal. Escape protein can be important to the ruminant because any rumen degradable protein that is not consumed by the microbes can be lost through the urine. However, when animals are consuming low-protein forages, as is often the case on rangeland, then a supplemental protein source is required to stimulate rumen microbial activity and encourage forage intake. For cattle consuming low protein forage, 60 to 70% of the supplemental protein should be ruminally degradable.
Early studies on nutritional wisdom focused on the innate ability of livestock to balance minerals in their diet. From these studies, nutritionists concluded that livestock are unable to consume minerals in correct quantities to prevent or correct mineral deficiencies and therefore are not nutritionally wise. However, many of the assumptions nutritionists held about diet selection are questionable if one considers that animals have to learn about foods before they can make correct choices. This fact sheet lists the assumptions implied by nutritional wisdom studies and alternative explanations about how animals learn about foods and nutrients, including minerals. Read more here.
Why do animals eat certain foods and live in certain locations? Every animal is born with a set of genes that determines how they look and what they need to survive, but genetics is only part of the story. As an individual grows, its body and physiology are shaped by experiences early in life. Changes within the body enable animals to adapt and thrive in a variety of environments. This fact sheet discusses how experiences early in life can shape an animal’s physiology, neurology, and morphology. Read more here.
Why do you like certain foods? Most people would say because they taste good, but research shows that palatability is much more than a matter of taste. Palatability is the interrelationship between a food’s flavor and its nutrient and toxin content. Palatability also depends on the nutritional needs of the animal and its past experience with the food. This fact sheet discusses in depth how animals learn which foods to eat and avoid, and what makes a plant palatable. Read more here.
We often buy and sell animals and move them to unfamiliar environments without considering where they were raised or their previous dietary experience — and then wonder why they don’t perform well. An animal’s performance depends on the amount and type of experience it has with the environment in which it is expected to forage. When bringing animals into a new area, managers can help ease the transition by: 1) selecting animals from areas similar to where they will be expected to graze, 2) introducing animals to foods they will encounter at new locations, 3) providing familiar foods at new locations, and 4) providing appropriate role models. This fact sheet discusses factors to consider when moving livestock to new environments. Read more here.
Understanding animal behavior is simple. All behavior is based on consequences. When an animal engages in a behavior, if the consequence of that behavior is positive, then the likelihood the animal will repeat that behavior increases. However, if the consequences are negative, then the likelihood the behavior will be repeated decreases. This fact sheet explains how behavior by consequences works to shape animal behavior and the pros and cons of shaping behavior with positive or negative consequences. Read more here.
Young livestock and wildlife learn what to eat and where to live based on interactions with their mothers. Young animals learn about foods in the womb prior to birth, from mother’s milk, and through interactions with mom while grazing. This fact sheet discusses the importance of mother on the dietary and habitat preferences of grazing livestock and wildlife. Understanding that experiences early in life shape these preferences can enable managers to shape animals to be more productive on rangelands. Read more here.
Herbivores forage in a complex environment. How do they learn which foods are nutritious and which foods are toxic or low in quality? Herbivores begin learning about what foods are safe before they are even born and continue the process throughout their life enabling them to survive in a world where toxin and nutrient levels of forages are constantly changing. These same processes allow them to make foraging decisions when they are moved to new pastures with unfamiliar foods.
Mom as a Role Model
A young animal first learns about which foods to eat and which to avoid by foraging with its mother. By the time the animal has to forage on its own, it is already familiar with a number of plants that are nutritious and safe to eat. Thus, an animal divides its foraging world into two food groups, familiar and novel. Animals learn through trial and error about novel foods based on the postingestive consequences of the novel foods they eat.
Like most people, herbivores sample novel foods cautiously. If the consequences of eating the food are positive--feedback from needed nutrients---the animal will increase intake of the new food. If the consequences are negative --illness from toxins or lack of feedback because the food is low in nutrients--the animal will decrease intake of the food. When eating a meal of several foods, novelty is the key to figuring out which foods are harmful and which are nutritious. When animals eat a meal of several familiar foods and a novel food and then experience illness, they subsequently avoid the novel food. Conversely, when animals suffering from a nutritional deficiency recover after eating a meal of several familiar foods and a novel food, they learn to prefer the nutritious novel food. Herbivores also reduce intake of familiar foods when the flavor of the food changes. Changes in flavor may occur when forages grow on different sites or as plants mature. If the change in flavor results in illness, the animal avoids the food in the future. If, however, the change in flavor results in positive consequences then the animal will continue to eat the food.
Herbivores continuously sample foods, even foods that made them ill. If an animal gets sick after eating a meal of several familiar safe foods and food that caused illness in the past, subsequently it will avoid the food that caused illness. Animals are able to remember which foods previously made them sick for a long time.
Animals use past experiences with familiar foods to make foraging decisions about new foods. If new foods have flavors simliar to foods that made the animal ill in the past, it is less likely to eat those foods. Conversely, if new foods have flavors similar to familiar nutritious foods, animals ingest those foods more readily.
Amount and timing
If the foods an animal eats during a meal are equally unfamiliar and the animal experiences illness, how does the body determine which food to avoid? Animals pair feedback--positive or negative--with the food they ate in the greatest amount, provided both foods are equally new. Animals also form aversions to or preferences for foods when food ingestion is quickly followed by either illness or positive postingestive signals, provided the foods are equally familiar to the animal.
At one time researchers thought animals formed aversions to certain strong flavors more readily than others. They referred to these flavors as salient. Bitter, for example, was thought to be a salient flavor because many toxic compounds are bitter. Further study indicated that the response the scientists observed was simply due to novelty. When animals are reared on bland foods and get sick after eating a meal of several foods, one of which has a strong novel flavor, they form an aversion to the food with the strongest flavor. If, however, they are reared on foods with strong flavors and get sick after eating a meal of foods with strong familiar flavors and a novel bland food, they form an aversion to the bland food. Thus animals associate illness with novelty not necessarily with strong flavors.
Animals depend on the availability of familiar foods to make correct foraging decisions. When animals are moved to new foraging locations that contain only novel foods, it is more difficult for them to select safe nutritious foods and to avoid toxic foods. Understanding how animals discern safe from harmful foods is important information managers can use to help animals make transitions to new locations or train animals to eat new foods.
Adapted from: BEHAVE
Animals learn which foods to eat by interacting with mother and herd mates, but in most cases they only continue to eat foods that provide nutritional or medicinal benefits. They can also learn about their physical environment and tend to live in areas that are safe. However, the body is designed to learn about foods and locations differently. This fact sheet discusses how animals learn about safe and harmful foods and locations. Understanding these differences is essential for managers who want to change animal behavior. Read more here.
Animals can learn to eat unpalatable plants and to mix palatable and unpalatable plants in their diets. The nutritional composition of an animal’s diet affects how much of these unpalatable plants animals can eat. Read more here.
Livestock can be trained to avoid plants by creating a food aversion using the drug lithium chloride. They can be trained to avoid poisonous plants that are problematic on rangelands. They can also be trained to avoid agronomic plants such as grapevines and fruit trees to allow livestock to graze for weed control in vineyards and orchards. Read more here.
Written by Jim Keyes - Utah State University Extension Area Animal Scientist
When winter hits and temperatures drop below freezing, it becomes harder to keep a fresh water supply for cattle grazing on range. It can be difficult to access areas to cut ice and open reservoirs or to haul tanks of water.
Many wonder if cows can eat snow in the winter to supply all their water needs. The answer is yes. There are many situations where cattle can survive on snow without having any other water supply. Many ranches throughout the West and Midwest with cattle on large pastures and few or no water resources depend entirely on snow for winter grazing.
Just turning cattle loose on the snow sounds like a very simple management technique, but it requires that ranchers pay very close attention to the animal’s body condition and general health.
Several studies have shown there is no reason to expect cattle performance to deteriorate when animals use snow for water. Researchers found cows using snow for water did not differ in live weight amount of body fat compared to cows receiving water.
Another study evaluated the effects of snow as a water source on milk yield and calf growth. A group of pregnant beef cows were provided only snow as a water source.
A similar group of cattle were given access to heated water. Cows eating snow consumed between 30 and 40 pounds of snow per day to meet their water needs. Cows with access to water drank 2 to 3 gallons, but also ate 7 to 25 pounds of snow. In the end, there was no difference in average milk yield or body weight between the two groups of cattle or the calves they produced.
Research in Montana showed when cattle have access to water and snow, 2% of cows never drank any water, and only 65% drank water every day. The other 33% drank every second or third day while eating snow the rest of the time. There was no visible difference in the appearance of any of the animals.
When using snow as the only water source, several points should be considered:
- Thin cattle (Body Condition Score of 3 or less) should not be forced to depend only on snow. Cattle should have at least a BCS of 4 and should be in good health.
- An alternate water source must be available in case conditions change and there is not enough snow to meet the herd’s water needs.
- Snow must be clean and accessible. Ice crusted, wind-blown or trampled snow is not adequate. It takes approximately 4 inches of snow to get a half-inch of water.
- Make certain feed intake does not decline. A mature cow will eat 2.5 percent of her body weight on each day. Reduction in feed intake may mean insufficient water intake.
- Eating snow is a learned behavior. It can take some cows 4 or 5 days to learn the technique. It’s always best to put inexperienced cows with herd mates that have experience using snow as a water source.
Cows can survive and do very well using snow as their only source for water. Ranchers can use pastures without water, increase the length of the grazing season, and save money by not having to provide water during times of snowfall. It is imperative, however, to continually monitor the feed intake and the body condition score of the cows.