In 1884, Takaki observed that beriberi was common among low-ranking crew who were often provided free rice, thus ate little else, but not among crews of Western navies, nor among Japanese officers who consumed a more varied diet. In 1897, Christiaan Eijkman, a Dutch physician and pathologist, demonstrated that beriberi is caused by poor diet, and discovered that feeding unpolished rice (instead of the polished variety) to chickens helped to prevent beriberi. The following year, Sir Frederick Hopkins postulated that some foods contained "accessory factors"—in addition to proteins, carbohydrates, fats, and salt—that were necessary for the functions of the human body. In 1901, Gerrit Grijns, a Dutch physician and assistant to Christiaan Eijkman in the Netherlands, correctly interpreted beriberi as a deficiency syndrome, and between 1910 and 1913, Edward Bright Vedder established that an extract of rice bran is a treatment for beriberi. In 1929, Eijkman and Hopkins were awarded the Nobel Prize for Physiology or Medicine for their discoveries. Etymology
Although according to the Oxford English Dictionary, the term "beriberi" comes from a Sinhalese phrase meaning "weak, weak" or "I cannot, I cannot", the word being duplicated for emphasis, the origin of the phrase is questionable. It has also been suggested to come from Hindi, Arabic, and a few other languages, with many meanings like "weakness", "sailor", and even "sheep". Such suggested origins were listed by Heinrich Botho Scheube, among others. Edward Vedder wrote in his book Beriberi (1913) that "it is impossible to definitely trace the origin of the word beriberi".
The most common cause is high-carbohydrate feeds, leading to the overgrowth of thiaminase-producing bacteria, but dietary ingestion of thiaminase (e.g., in bracken fern), or inhibition of thiamine absorption by high sulfur intake are also possible. Another cause of PEM is Clostridium sporogenes or Bacillus aneurinolyticus infection. These bacteria produce thiaminases that can cause an acute thiamine deficiency in the affected animal. Snakes
Snakes that consume a diet largely composed of goldfish and feeder minnows are susceptible to developing thiamine deficiency. This is often a problem observed in captivity when keeping garter and ribbon snakes that are fed a goldfish-exclusive diet, as these fish contain thiaminase, an enzyme that breaks down thiamine. Wild birds and fish
Thiamine deficiency has been identified as the cause of a paralytic disease affecting wild birds in the Baltic Sea area dating back to 1982. In this condition, there is difficulty in keeping the wings folded along the side of the body when resting, loss of the ability to fly and voice, with eventual paralysis of the wings and legs and death. It affects primarily 0.5–1 kg-sized birds such as the European herring gull (Larus argentatus), common starling (Sturnus vulgaris), and common eider (Somateria mollissima). Researches noted, "Because the investigated species occupy a wide range of ecological niches and positions in the food web, we are open to the possibility that other animal classes may develop thiamine deficiency, as well."p.