Dog owners whose four-legged friends suffer from chronic illnesses turn to us time and again. They want to know which dog foods are suitable for feeding in the presence of various diseases. Leishmaniasis is a frequent topic of discussion. But what exactly is leishmaniasis and what do you need to bear in mind when feeding it? Why should you feed your dog as little purine as possible?

Leishmaniasis - an overview

Leishmaniasis is an infectious disease. The pathogens are protozoa, i.e. protozoa that are transmitted by sand flies. Other forms of transmission (blood transfusions, smear infections) are rare. For a long time, sand flies were only found south of the 45th parallel. This means that dogs from countries in the Mediterranean region or accompanying their owners on vacation were infected. Recently, the occurrence of sand flies has been observed in southern Germany. Leishmania infections could also occur in these regions in the future.

Transmission and symptoms

The pathogens are transmitted during the sucking act of the female mosquito. The leishmania then parasitize intracellularly, especially in macrophages (cells of the immune system). It is interesting to note that infected dogs do not necessarily have to fall ill. This means that they may harbor the leishmania, but may never develop symptoms. It is difficult to predict if and when the disease will break out. There is a correlation between the level of the antibody titer (number of antibodies present in the blood that have been produced by the dog's body against the pathogens) and the likelihood that symptoms will occur.

These symptoms are often initially non-specific and occur in episodes. They include fever, apathy, emaciation and a pale coat. Depending on the course of the disease, different forms of manifestation become apparent. A distinction is made between cutaneous (skin: including hair loss on the bridge of the nose, tips of the ears, "spectacle formation" around the eyes), mucocutaneous (mucous membrane: ulcers) and visceral (internal organs: especially glomerulonephritis → inflammation of the kidneys) forms. All can also occur in combination. Without treatment, up to 90% of dogs that have actually developed leishmaniasis die.

What does treatment look like and what does this have to do with nutrition?

First of all, important information: Leishmaniasis is NOT curable in dogs. Although it is possible to alleviate the symptoms through the targeted use of various medications, the pathogens are very likely to remain in the dog's body for the rest of its life. A renewed outbreak of the disease is not unlikely even after the symptoms have successfully subsided, which makes renewed therapy necessary.

A commonly used medication is "allopurinol", which is used to treat gout in humans, among other things. It is absorbed by the Leishmania and ultimately inhibits their multiplication. However, it also has a different effect directly in the dog itself. It hinders the enzymatic degradation of purines to allantoin. Purines are important components of DNA and RNA and can be synthesized by the dog itself. All purines that additionally enter the organism through food and are not required for the synthesis of genetic material must be broken down and excreted by the kidneys.

If the breakdown to allantoin is inhibited by the leishmaniasis drug "allopurinol", the intermediate product xanthine accumulates to a greater extent. There is a risk of urinary stones ("xanthine stones") forming. This is the reason why dogs receiving allopurinol should be fed a low purine diet. This may not be so easy, as only a few feed manufacturers declare the purine content of their products and creating a recipe yourself is time-consuming and requires specialist knowledge. Pet owners should not be afraid to contact the producers of their dog food directly and ask about the purine content. If information is withheld, it is advisable to change the product.

Low-purine diet - an overview

Purines are increasingly found in foods rich in cell nuclei. These include meat (especially offal and connective tissue chews), but also legumes. Depending on its composition, a vegetarian or vegan diet can be a very favorable alternative to a meat diet.

The purine content of our VEGDOGvarieties is as follows:

There are currently no official recommendations or limits for low-purine feed. However, based on the current study situation, complete feeds with a purine content of approx. 40 mg/100 g dry matter can be classified as low purine (cf: Kaempfle et al. (2023), Animals,13,3060. https://doi.org/10.3390/ani13193060).

Thus, we can recommend our FARMER'S CRUNCH for a low-purine diet.

It should also be noted that dogs with leishmaniasis should drink a lot. Diluting the food portions with water can be very useful.

How long is the life expectancy of infected dogs?

Leishmaniasis is not a death sentence. The majority of infected dogs have the chance of a long and happy life. We owners have a responsibility to promote this. This includes reducing stress (because this weakens the immune system) by creating a regular daily routine, lots of love and attention, regular veterinary check-ups, the administration of appropriate medication if necessary and, of course, a wholesome and balanced diet.

Is leishmaniasis contagious?

In principle, leishmaniasis is not contagious - neither from dog to dog nor from dog to human. Only a pregnant bitch can transmit the parasites to her puppies via the placenta. Otherwise, transmission occurs via the bite of an infected female sand fly. However, the sand fly can also become infected with Leishmania in a dog and pass the infection on to humans or animals with the next bite.

If you have any questions about this disease, please feel free to contact our vets on tierarzt@vegdog.de.