The liver – a multi-talented organ

The liver is located in the abdominal cavity directly next to the diaphragm and as a central organ of the body plays an important role in metabolism. It’s variety of functions make it a true multi-talent. Nutrients like fats, sugars, amino acids and vitamins are brought to the liver from chyme over the portal vein and absorbed by the liver cells. Depending on requirements, these nutrients are then broken down or converted. It can also form new sources of energy for the body. As a detoxification organ, the liver can also break down and excrete harmful substances that are either absorbed from food or created through metabolic processes. Without these functions, the body can suffer serious consequences. The liver also has the important function of forming bile acids. Bile acids serve to digest fats as well as to absorb fat-soluble vitamins. Since horses do not have gall bladders, gall is not stored in an intermediate location but is sent directly to the small intestine. The liver also serves as a storage location for important nutrients such as vitamin A, sugar and minerals.

These functions may be impaired if the liver is diseased. Important indicators for liver ailments are increased liver enzyme levels. These enzymes are released by damaged liver cells (hepatocytes) and then enter the bloodstream. However, in practice, elevated liver enzyme levels are often determined through routine examinations of horses, without the observation of clinical symptoms. This is due to the liver’s enormous capacity for regeneration. Clinical symptoms first appear after 60–70 percent of the liver’s capacity to function is destroyed. Typical signs of liver problems are emaciation, diminished performance and lethargy. In the worst case, severe liver insufficiency and the resulting inadequate detoxification can lead to serious clinical symptoms such as disorders of the central nervous system (hepatic encephalopathy), which can result in impairments of movement and clouding of consciousness.

If liver enzyme levels are found to be elevated, all possible causes, both nutritional and non-nutritional, should be clarified. Nutritional causes may include the ingestion of poisonous plants, mushrooms, mycotoxins and toxic substances. However, a chronic vitamin E deficiency can also cause elevated liver enzyme levels. Non-nutritional causes include infections, fatty degeneration of the liver due to hyperlipemia (release of stored fat as a result of hunger caused by stress factors in ponies or donkeys that are otherwise well-nourished), parasite infestation and liver tumours, the latter however being rare in horses. Chronic metabolic ailments like Equine Cushing’s Disease can elevate liver enzyme levels. However, with liver disease it is generally very difficult to determine the cause.

In addition to the treatment of the underlying disease, it is advisable to adapt the feeding of the affected horse in order to relieve the liver. The course of the disease should also always be followed by regular monitoring of liver enzyme values. Changes in the liver such as cirrhosis and fatty degeneration of the liver can usually not be reversed through dietary measures. Proper diet, however, can reduce the consequences of inadequate detoxification.
 

Feeding measures for liver problems

Since insufficient bile acid formation in liver diseases can reduce the digestion of fat, the horse should be given a reduced-fat feed to relieve the strain on the liver. This can also reduce the absorption of fat-soluble vitamins, which is why it may be necessary to supplement these vitamins, depending on the extent of the dysfunction.

In the case of acute liver diseases, a low-protein diet should be introduced due to the impaired detoxification function of the liver.

In addition, it is recommended that frequent small meals, instead of fewer large ones, be provided to avoid the intermittent flooding of protein breakdown products. It is necessary to keep blood sugar levels constant in order to counteract the mobilisation of protein as an energy source. Low-protein hay, Pre Alpin® Protein Light Flakes and processed cereals such as AGROBS Maiscobs are a possible sources of energy for liver problems. AGROBS Maiscobs contain the entire maize plant and thus offer a high crude fibre content in addition to highly digestible cereals.

Low-protein and low-energy AGROBS LeichtGenuss is also very suitable as a concentrate alternative or supplement to base feeds for horses and ponies that are good doers and have elevated liver enzyme levels.

In the case of liver problems, it is recommended to carry out a liver detoxification cure with e.g. Bergsiegel Kräuter for the liver. Bergsiegel’s herbal mixture for the liver contains tannins and bitter substances that promote the cleansing and regeneration of the liver. Alternatively, Bergsiegel Mariendistelfrüchte is also suitable for supporting liver function. Bergsiegel’s Kräutermischung for the liver likewise contain milk thistle fruits. However, regular liver detoxification is not only beneficial for horses with liver problems – healthy horses will benefit from this as well. It also combines very well with kidney detoxification, because both the kidney and liver are important detox organs. Such detoxification treatments are sensible in spring and autumn, when metabolism is higher. One can, for example, carry out a detox programme for the kidneys in spring (for instance with Bergsiegel Kräuter for the kidneys) and for the liver in autumn. 




Sources*:    
  • Meyer H., Coenen M.: Pferdefütterung. Enke Verlag Stuttgart, 2014    
  • Moritz A.: Klinische Labordiagnostik in der Tiermedizin. Schattauer Verlag 2014    
  • Dietz O., Huskamp B.: Handbuch Pferdekrankheiten. Enke Verlag Stuttgart, 2006    
  • Taylor F., Hillyer M.: Klinische Labordiagnostik in der Pferdepraxis. Schlütersche Verlagsgesellschaft mbH & Co. KG, 2004    
  • Von Engelhardt W., Breves G.: Physiologie der Haustiere. Enke Verlag Stuttgart, 2000    
  • König H., Liebich H.-G.: Anatomie der Haussäugetiere. Schattauer Verlag, 2012    
  • Higgins A., Snyder J.: The Equine Manual. Elsevier Sauders, 2006  
 

Dr. med. vet. Katharina Boes
May 2016 ©AGROBS GmbH 



 
(* The references refer to the technical content of the text and not to the product recommendations.)