Syrian Hamsters in Leishmaniasis study

Syrian hamsters were first introduced to the scientific parasite community by Adler and Theodor when they were used in visceral leishmaniasis studies! SHOCK HORROR RIGHT And they were then quickly accepted and used in various studies from leprosy to encephalitis to reproduction and more.

I am going to be honest when I think of laboratory animals its usually rats, insects or even fish but not Syrian Hamsters. That’s probably because I have the most adorable little girl Patricia (photo above) who I love like my child and would not ever think of her as a rodent experimental model, but why not? I think of rats as laboratory animals used for experiments and they are peoples loved pets!

Mesocricetus auratus aka Syrian hamster that are utilized as laboratory animals all originate from one litter captured in Syria in the 1930’s.

Why use Mesocricetus auratus?

-They reproduce easily and have a short life cycle.

-They have an eversible cheek pouch that can be easily used for transplantation.

-Their embryonic cells can be genetically manipulated for successful transgenic or knockout hamster model.

-They display many features that resemble humans in physiology eg metabolism, infection of pathogenic microorganism etc.

-They have a good size (compared to mice) to visualize certain biological systems such as reproductive systems.

-They develop inherited disease similarly to humans and are susceptible to disorders through dietary manipulations.

-They are susceptible to infection from pathogenic agents.

All these make them desirable research models just like rats, however their use has declined over the years.

Mice vs Hamsters in visceral leishmaniasis (VL) studies?

Mice infected with L. donovani have been widely studied, but this model does not reproduce the features of active human VL. In this animal, there is an early increase in parasite burden, but over the course of 4–8 wk the infected mouse is able to mount an anti-leishmanial cellular immune response and control the infection. In contrast, the clinicopathological features of the hamster model of VL closely mimics active human disease. Systemic infection of the hamster with L. donovani results in a relentless increase in visceral parasite burden, progressive cachexia (weakness and wasting of the body), hepatosplenomegaly (enlargement of the spleen and liver), pancytopenia (deficiency of red cells, white cells and platelets), hypergammaglobulinemia (increased immunoglobulin), and ultimately death due to the uncontrolled parasite replication at these sites. So, for leishmanial studies hamsters mimic a human much better making them a better experimental model for us.


A) Macroscopic features of VL in an infected and uninfected hamster. The infected hamster is thin, exhibiting dramatic weight loss. The infected spleen is enlarged and the infected liver has a slight colour change, is fibrotic and containing many raised white foci (yellow arrows). From A New Model of Progressive Visceral Leishmaniasis in Hamsters by Natural Transmission via Bite of Vector Sand Flies (Aslan et al, 2013)

As someone who strongly believes that animal models are very important and necessary as well as being a hamster mum, reading about hamster use in research has made me feel uncomfortable. However, I am not going to let emotions affect the reality that when you need to find out more about what happens to the complex whole living body, in most cases nothing can replace the use of living animals.

Studies using Syrian Hamsters:

Food-Anticipatory Activity in Syrian Hamsters: Behavioral and Molecular Responses in the Hypothalamus According to Photoperiodic Conditions (Dantas-Ferreira et al, 2015): https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4430487/ 

Experimental Models in Syrian Golden Hamster Replicate Human Acute Pancreatitis (Wang et al, 2016): https://www.nature.com/articles/srep28014

The Hamster as a Model of Human Visceral Leishmaniasis: Progressive Disease and Impaired Generation of Nitric Oxide in the Face of a Prominent Th1-Like Cytokine Response (Melby et al, 2001): http://www.jimmunol.org/content/166/3/1912