Neurodegeneration in equine grass sickness is not attributable to niacin deficiency

Abstract

Niacin deficiency does not contribute to EGS neurodegeneration.

Nicotinic acid supplementation at a supraphysiological dose increases the bioavailability of NAD+ precursors in mares

“…While the number of mares examined here was small, the results indicate that the excretion of NA metabolites differs markedly between horses and humans. Alternatively, as the findings of previous horse studies suggest (McGorum et al, 2017; Parker et al, 1997), the mares were in fact niacin deficient and utilised more of the supplement to compensate for this deficiency. We estimate that as much as half of the administered NA was distributed by the mares’ circulation for utilisation by cells and tissues throughout their body.…”

“…Additionally, in exercising horses, Parker et al, (1997) observed no effect of 6 weeks of nicotinic acid supplementation on niacin status, as determined by the NAD: NADP ratio in red blood cells. Based on reference ranges for the NAD: NADP ratio in humans, the niacin status has previously been considered deficient in horses (McGorum et al, 2017; Parker et al, 1997). While there is no known dietary requirement for niacin in healthy horses, the levels of niacin metabolites needed to support optimal equine reproductive performance have yet to be established.…”

Can Nicotinamide Adenine Dinucleotide (NAD+) and Sirtuins Be Harnessed to Improve Mare Fertility?

“…Since elevating the levels of NAD + in oocytes and embryos both in vitro and in vivo has beneficial effects in other species [10,[12][13][14][15][16][17][18][19][20][21], can reproductive efficiency in the mare be improved through promoting NAD + biosynthesis via dietary interventions? There has been no evidence of niacin deficiencies in horses [22] and the additional supplementation of niacin had no effect on exercising Thoroughbred geldings [23]. However, niacin is one of the more commonly added vitamins in pelleted horse feed.…”