Long term effect of post-weaning rhythm on the body fat and performance of rabbit doe

Abstract

-Reproductive protocols based on standard (Control: 11 days post-partum) or extended rhythm (PW: post-weaning at 27 days post-partum) were compared. Two groups of fifty 19-weekold New Zealand White females were inseminated for seven consecutive cycles. The kits were weaned at 26 days. On the day of AI, all the does were submitted to ultrasound scanning of the perirenal regions to measure fat thickness. The fertility rate and several indexes of efficiency were calculated. Fat thickness, estimated perirenal fat and live weight were higher in PW does. The does submitted to post-weaning rhythm had a higher sexual receptivity (P < 0.01), and fertility rate (P < 0.01) whereas litter size and pre-weaning mortality were not affected. Primiparous Control does showed a particularly low fertility rate; the value increased successively but was always lower than in PW does. PW rhythm in comparison with the standard one seemed more adapted to doe reproductive physiology even if there was a lower production (35.0 vs. 38.8 rabbit sold/year) and risk of fatness (18% of multiparous does). rabbit doe / fertility / rhythm of insemination

Effect of Light Colour and Reproductive Rhythm on Rabbit Doe Production

“…Similarly to our results, Feugier and Fortun-Lamothe (2006) reported differences between females inseminated at 11 d and weaned at 35 d with those inseminated at 25 d and weaned at 23 d. Castellini et al (2006) recorded higher body weight in the groups inseminated at 27 d post-partum. The authors considered this result to be the consequence of a possible better body condition of the latter inseminated group's better condition.…”

“…Castellini et al (2006) found similar results, as the proportion of the replacement does was lower in the group inseminated at 27 d than in the other group where insemination took place at 11 d (60 and 80%, respectively). Higher survival (longevity) could be related to the better body condition (Castellini, 2007).…”

“…Litter weight at birth, at 23 d and the individual weight at 23 d of lactation were higher in 42D than in 56D group (P=0.006, P=0.057 and 0.055, respectively). Xiccato et al (2005), Feugier andFortun-Lamothe (2006) and Castellini et al (2006) observed similar tendencies. It seems that the longer resting period after kindling could have a favourable effect on the kindling rate but not on the litter size and litter weight.…”

“…The differences between the two groups were much smaller than reported in the literature (Feugier and Fortun-Lamothe, 2006;Xiccato et al, 2005;Castellini et al, 2006). The reason for this finding may be that inseminating the does two days after weaning (25 d postpartum) and the own early weaning had a positive effect on receptivity, so in the 42D group prior to insemination the nursing method was modified from free to controlled nursing with the aim of biostimulation.…”

“…Castellini et al (2006) also found significant differences but, because of the weak pregnancy rate following insemination at 11 d, the difference between the two groups was only 8 d.…”