Prevention of rumination disorders in cattle is the best choice to have a healthy herd and avoid multiple digestive diseases.

What characterizes a ruminant animal?

Animals that are called ruminants include those that have a digestive organ called the rumen. This group includes domestic animals such as cattle, buffaloes, camelids (camels, dromedaries, alpacas, vicuñas, llamas), goats, and sheep.

The rumen is a large capacity glandular sac where fermentative processes of the food consumed by animals take place. There are populations of billions of microorganisms such as bacteria, protozoa, fungi, and archaea in the rumen. This population is called microbiota. These microorganisms are the ones that digest and process all the plant material that is consumed by ruminants. They then release volatile fatty acids (VFA) that are absorbed by ruminants and constitute their main source of energy. In addition, CO2, and methane CH4 are released in this process. An imbalance in these processes leads to alterations in rumination.

In the rumen, there are physiologically controlled conditions that, when there are abrupt changes, lead to diseases and disorders. The microbiota is also susceptible to these changes and therefore, many microorganisms end up dying. Most ruminal bacteria bind to fibrous plant material and produce amylase and proteolytic enzymes to digest it. However, when they begin to die, ruminal disorders manifest themselves in a variety of ways.

What are the main rumen disorders?

The rumen is a giant sac that occupies more than half the volume of the abdomen in ruminants. In cattle, it has a capacity between 100 and 150 liters, while in sheep it is 6 liters. When imbalances appear in the rumen, biochemical, biophysical, and microbiological changes occur and interfere with the rumination process. Rumination disturbances can be either mechanical or fermentative.

Alterations of the rumination of mechanical type

1. Traumatic reticulo-peritonitis.

This alteration of rumination is caused by the ingestion of a foreign body of a sharp type. Cows are animals that do not differentiate or select their feed and during consumption may ingest foreign objects. Among the most frequent elements are laces, pieces of metal, wires, among others. These objects get lodged in the reticulum next to the rumen and through digestive movements end up perforating the organs. The perforation of the rumen and reticulum can result in the perforation of the peritoneum as well. This disorder generates rumen paralysis (hypomotility) and can lead to the death of the affected animals.

2. Vagal indigestion.

Vagal indigestion is an alteration of rumination that occurs due to the involvement of the vagus nerve (cranial nerve X). It produces two main types of disorder: The first is called Anterior Functional Stenosis Syndrome, which makes it very hard the pass of food in the reticulo-omasal orifice. The second is called posterior functional stenosis syndrome, which inhibits the passage of the food bolus into the pylorus. Vagal indigestion generates signs such as anorexia, tenesmus, severe abdominal distension due to gas accumulation, and general deterioration. Animals are at high risk of death due to this alteration of rumination.

3. Ruminal tympanism

This alteration of rumination is an evident sign in animals; it can have several causes. Ruminants eliminate the gases produced in fermentation through belching. If there is any obstruction (in the esophagus, for example) or digestive alteration (foamy tympanism, for example) that prevents the release of eructation, the gas will start to accumulate in the rumen. This accumulation of gas leads to distension of the rumen and compression of the other organs. It can become fatal if the distension is not treated in time or is severe because it compresses the lungs preventing the animal from breathing.

Alterations in rumination of fermentative type

1. Rumen dysbiosis

In this disorder, there is a change in the population proportion of microorganisms inhabiting the rumen. This affects a change in the digestion processes of ruminants.

2. Simple indigestion

Ruminants can sometimes accidentally consume foreign materials such as plastics. This type of object lodges in the rumen and due to its nature and size, it is trapped and cannot be digested by the animals. Simple indigestion generates an alteration of rumination and can become complicated, endangering the animal’s life.

3. Ruminal acidosis

Ruminal acidosis is perhaps the best-known rumination disorder due to its clinical importance and frequency of cases. This ruminal disorder is complex because of all the changes that occur in the rumen and is the most serious of all. It is mainly caused by abrupt changes in the diet and the increase of easily digestible carbohydrates. The microbiota, especially the bacteria Streptococcus spp. and Lactobacillus spp. convert these carbohydrates into lactic acid. The formation of lactic acid as a metabolic product affects not only the rumen but also generates an acid-base imbalance in the animal. Death can occur within 24 hours.

Prevention of rumination disorders

The actions taken to prevent rumination disturbances should be multiple. In general, one should try to prevent all the alterations previously described because they affect production and can lead the animal to death.

1. Cleaning of pastures: the facilities where ruminants are housed must remain totally clean. Care must be taken with plastic residues, sharps, garbage, and other types of materials that can be ingested by ruminants.
2. Use of magnets to trap sharp materials of metallic nature, since they are the most frequent in traumatic reticulo-peritonitis. A magnet can be administered orally to affected ruminants to trap metallic materials and prevent perforation of the digestive organs.
3. Avoid abrupt changes in the diet: this type of event favors the biochemical imbalance of the fermentation process in the rumen. Dietary changes should be made gradually.
4. Avoid excess of easily digestible carbohydrates: it is necessary to give the exact and necessary quantities of carbohydrates in the diet of ruminants. Foods such as fruits and feed grains should be given with caution to avoid excess carbohydrates. These substances are the ones that trigger ruminal acidosis.
5. Use of forages: if there is a shortage of pasture due to the summer season, it should be avoided to increase the amount of feed. Instead, it is recommended to have forage reserves in the form of silage or hay to supplement the animals’ feed.
6. Avoid cut forages: sometimes it is considered to feed the animals with some forage cut with mowers or machines that form fine particles. Animal does not correctly perform the rumination process in small particles, decreases the production of saliva, and generates ruminal acidosis.
7. Herd health: it is recommended that ruminant farms manage a herd health program that guarantees the best condition of the animals. Some of the alterations in rumination are a consequence of disorders of other organs or systems and should be prevented.
8. Addition of sodium bicarbonate: the veterinarian can calculate an amount of sodium bicarbonate to administer to cows at risk of developing ruminal acidosis.
9. Use of probiotics: it has been proven that adding essential oils or yeasts in the diet such as Saccharomyces cerevisiae and Megasphaera elsdenii has a protective effect against rumination disorders.
10. Rumination stimulants: products such as Alquerplus ruminatorio enhances the rapid development of the rumen microbiota in critical periods for the digestive system (weaning, change of diet) and facilitate the digestion of the most important components of the feed. This product contains vitamins, amino acids, mineral salts, and probiotics (to repopulate the microbiota), and pronutrients (improve digestive physiology). It is essential that the rumination process is correct to prevent the appearance of metabolic diseases in ruminants and that organic functions are adequate.

Conclusions

Ruminants include a large group of animals such as cattle, camelids, goats, and sheep. They are characterized by having a giant fermentative sac called rumen where the food they consume is processed.

However, this large organ can suffer from mechanical or fermentative alterations that induce disease processes affecting ruminants. These rumen problems are frequent in livestock, and it is important to recognize and prevent them.

Mechanical disorders include traumatic reticulo-peritonitis, vagal indigestion, and ruminal tympanism. On the other hand, fermentative disorders include ruminal dysbiosis, simple indigestion, ruminal acidosis.

Thus, it is essential to consider the prevention of these rumination disorders. Prevention mechanisms are related to pasture cleaning, adequate feed supply (forage or feed), and the use of compounds as rumination stimulants to promote rumen health.