Resumen de Efecto de la subnutrición materna periconcepcional sobre los resultados reproductivos de ovejas y la calidad Oocitaria de sus corderas
José Alfonso Abecia Martínez, F. Forcada, I. Contreras, A. Meikle, C. Sosa, A. Casao
Eighty ewes were fed to provide 1.5 (control group, C, n=40) or 0.5 (low group, L, n=40) times their maintenance requirements, from pessary insertion until 7 days after oestrus (day 0). Diets provoked a significant reduction (p<0.05) of live weight (LW) and body condition in the L group. Undernourished ewes presented a significant lower litter size (C: 2.06±0.16; L: 1.59±0.12 lambs per lambing; p<0.05) and fecundity (C: 1.60±0.18; L: 1.07±0.14 lambs per ewe; p<0.05). Lambs from the L group had a significant higher LW at lambing (p<0.05), although no differences in LW at weaning or mean dairy LW gain were observed. Six ewe lambs were euthanized at 2 months of age and their oocyte quality studied. Animals born from L ewes presented more oocytes than from C ewes (140.0±18.5 vs. 60.0±7.8, resp.; p<0.05), although percentages of healthy oocytes were similar. Ewe lambs from L ewes also presented a higher maturation rate (p<0.10) with similar fecundity, cleavage and blastocyst rates. In conclusion, periconceptual maternal undernutrition produced a significant reduction of lamb production. Moreover, lambs from these ewes presented a significant higher LW at lambing and ewe lambs an alteration of oocyte quantity but no quality. These differences could have consequences in the adult life.
