Extensive reproductive rhythm and early weaning improve body condition and fertility of rabbit does

Un rythme de reproduction extensif associé à un sevrage précoce améliore l’état corporel et la fertilité des lapines

Alexandre Feugier (1) , Laurence Fortun-Lamothe (1) , . Station de Recherches Cunicoles (1)

1 Station de recherches cunicoles

This research was aimed at evaluating the respective influence of reproductive rhythm (R), artificial insemination (AI) performed on the 11th or the 25th day after kindling, and age at weaning (W) at 23 or 35 days of lactation, on the evolution of body condition and reproductive performance of rabbit does. Immediately after the initial kindling 12 does were selected for initial slaughter. The 234 primiparous does were assigned at their first parturition to one of four treatments: R11W23, R11W35, R25W23 and R25W35. The does representative of each experimental group were slaughtered at successive stages of the reproduction cycle to evaluate reproductive performance or body condition. When artificial insemination was performed 25 days compared to 11 days after kindling, main dissectible fat weight of the does was lower at insemination (67 g vs. 98 g in R25 and R11 does respectively; P < 0.001). But main dissectible fat weight at second parturition was higher in the R25 than in the R11 group (+27.3%; P < 0.001). From the first kindling to AI, the energy balance of does was positive in the R25 group and negative in the R11 group (+847 kJ·kg−0.75 vs. –729 kJ·kg−0.75 in R25 and R11 does respectively; P < 0.015). Moreover,the R25 does had a higher sexual receptivity at AI (+24 points; P < 0.001), and pregnancy rate (+16 points; P < 0.05) than the R11 does. Additionally, foetal viability (+5.4%; P < 0.05) was higher in the R25 than R11 groups whereas the number of corpora lutea, number of kits born alive and weight of litter at birth were not affected by reproductive rhythm. An early weaning did not affect the reproductive performance of the does but significantly reduced the main dissectible fat mobilisation (–35% vs. –54% in W23 and W35 groups respectively; P < 0.001) and increased live body (+135 g vs. –32 g, P < 0.005), empty body (+78 g vs. –93 g, P < 0.001) and defatted carcass weight gains (+79 g vs. –19 g, P < 0.001) from 1st to 2nd parturition. The present results demonstrate that limiting the nutritional solicitation of females by shortening the duration of lactation or the length of superposition between lactation and pregnancy, reduces the body fat mobilisation of primiparous does. The effects of reproductive rhythm and weaning age on corporal condition add together.

Mots clés: REPRODUCTIVE RHYTHM; WEANING AGE; REPRODUCTIVE PERFORMANCE; BODY CONDITION; ETAT CORPOREL

Mots clés: RABBIT DOES

Domaines: Science des productions animales

Alexandre Feugier, Laurence Fortun-Lamothe, . Station de Recherches Cunicoles. Extensive reproductive rhythm and early weaning improve body condition and fertility of rabbit does. Animal Research, 2006, 55 (5), pp.459-470. ⟨hal-02663997⟩