RT Journal Article
T1 Variability of plasma melatonin level in pony mares (Equus caballus), comparison with the hybrid : mules and with jennies (Equus asinus)
A1 Guillaume, Daniel
A1 Zarazaga Garcés, Luis Ángel
A1 Malpaux, Benoît
A1 Chemineau, Phileppe
AB In long-day breeders like horses, the length of nocturnal melatonin secretion is themain messenger of photoperiod. Previous studies have shown that the nocturnal jugular melatoninconcentration is lower in horses, than in mules but is unknown in donkeys. The aim of this studywas to estimate the inter-animal variability of plasma melatonin concentration in domestic maresand to compare this concentration with those observed in domestic jennies and in their hybridmules. In the autumn, blood samples were collected at 22 h, 23 h, 0 h and 1 h during 2 nights at3 weeks intervals, in 110 pony mares, 10 jennies and 6 mules maintained under natural photoperiod.Melatonin was assayed by a validated RIAmethod. The statistical analysis of themeasures was donewith a specific unbalanced analysis of variance model. The effect of species and individuals (nestedunder species) was highly significant. The mean melatonin concentration was 24 pg.mL−1 in maresand was significantly lower than in jennies and in mules which were 90 pg.mL−1 and 169 pg.mL−1respectively. The melatonin plasma concentration was higher in jennies than in mares. These resultssuggest that the melatonin concentration is genetically determined.
PB Institut National de la Recherche Agronomique (INRA)
SN 0926-5287
SN 1297-9708 (online)
YR 2006
FD 2006
LK http://hdl.handle.net/10272/6387
UL http://hdl.handle.net/10272/6387
LA eng
NO Guillaume, D., Zarazaga Garcés, L.A., Malpaux, B., Chemineau, P.: "Variability of plasma melatonin level in pony mares (Equus caballus), comparison with the hybrid : mules and with jennies (Equus asinus)". Reproduction Nutrition Development . Vol. 46, pág. 633-639 (2006). ISSN 0926-5287
DS Repositorio Institucional de la Universidad de Huelva
RD 31 may 2026