Reprod. Nutr. Dev. 44 (2004) 333-339
DOI: 10.1051/rnd:2004038

Ovulation rate, litter size and prenatal losses in hair sheep of the French West Indies

Maurice Mahieu^a, Yves Cognié^b and Philippe Chemineau<sup>b

a</sup>  Unité de Recherches Zootechniques, INRA-Antilles-Guyane, Prise d'eau, 97170 Petit-Bourg, Guadeloupe, France
^b  Physiologie de la Reproduction et des Comportements, UMR 6073 INRA-CNRS-Université de Tours, 37380 Nouzilly, France

(Received 3 September 2003; accepted 19 March 2004)

Abstract - Ovulation rate (OR) and litter size (LS) were recorded in local hair sheep of Martinique and in local × Lacaune-viande crossbreeds, in order to assess prenatal losses. Local hair sheep LS and OR were 1.91 and 2.41, respectively. Prenatal losses increased with OR, from 0.22 (OR = 2) up to 1.50 (OR > 3). The ewes (69.7%) with LS = 1 had actually lost at least one ovum, against 25.9% of the ewes with LS > 1. Ewes grazing Cynodon nlemfuensis (Stargrass) had lower LS than those grazing Digitaria decumbens (Pangola), in relation with a lower nutritional level and, maybe, more parasitism effects. No seasonal or age at lambing effect was shown. The OR and LS were dramatically decreased on local × Lacaune-viande crossbred ewes (minus 1.32 and 0.67 unit, respectively, P < 0.05). This suggests a possible negative effect of the tropical environment on the crossbreeds' reproductive function.

Key words: ovulation rate / litter size / prenatal losses / humid tropics / hair sheep / Lacaune-viande / crossbreeding

Corresponding author: Maurice Mahieu mahieu@antilles.inra.fr

© INRA, EDP Sciences 2004