25.05.2023: Niacin, formerly also known as vitamin B3, is involved in metabolism in mammals, has an antioxidant effect and is important for the regeneration of skin, muscles, nerves and DNA. A recent study at the University of Veterinary Medicine in Vienna investigated how a deficiency of niacin in brown hares affects reproductive performance: Reproductive performance does not take a hit, but there are clear negative effects on the body weight of the young hares.
Large areas of maize in agricultural landscapes are associated with reduced reproductive performance of females and impaired population development of free-living brown hares (Lepus europaeus). As part of an experimental study, a research team from the Vetmeduni therefore investigated captive brown hares to determine whether these effects were due to an undersupply of niacin from a maize-heavy diet.
Lower body weight with a low-niacin diet
In the study, adult female hares were repeatedly mated. They were fed either a low-niacin pellet consisting mainly of corn plant parts or the same pellet enriched with niacin to meet physiological requirements.
The researchers measured the effects of the experimental feeding on female weight, reproductive performance, growth and survival of the young bunnies. "The body weight of females fed a niacin-rich diet was significantly higher and their young gained weight significantly faster," said study first author Aldin Selimovic of the Vetmeduni's Research Institute of Wildlife Ecology (FIWI).
No significant difference in reproductive success
However, the researchers found no significant difference between a niacin-deficient and a niacin-enriched diet in terms of the reproductive performance of females and the survival rates of their offspring. "Our results show that even a niacin-deficient diet only slightly affects the reproductive success of female field hares, presumably due to sufficient conversion of tryptophan to niacin or an additional supply of niacin from microorganisms in the caecum," Selimovic says. "The effects we found on the weight development of young hares in our animal husbandry could be much stronger in the wild - where the young hares are exposed to wind, rain and cold - and could strongly influence the survival of the young hares," Selimovic adds.
Life-threatening niacin deficiency in humans
After the arrival of Christopher Columbus in America, corn was one of the first crops to be brought to Europe. Due to its high yields, it quickly spread around the world and became a staple food for many people. However, the form of nicotinic acid (niacytin) bound in it cannot be utilized by the human body. As a result of an unbalanced diet, the deficiency disease pellagra often occurred in the past, which can lead to death if left untreated.
The a rticle "The effect of dietary niacin deficiency on reproduction of European brown hares: An experimental study" by Aldin Selimovic, Mathilde L. Tissier, Gabrielle Stalder, Johanna Painer-Gigler, Anna Haw, Hanna Rauch, and Walter Arnold was publishe in „Frontiers in Ecology and Evolution“.
Scientific article