Using Marine Algae (Nannochloropsis oculata) as Natural Feed Additives to Improve Reproductive Performance in Rabbits

The present study was carried out to investigate the effect of using marine algae (Nannochloropsis oculata) instead of equine chorionic gonadotrophin (eCG) on improving productivity and reproductivity of rabbits. Thirty secondiparous Hy-plus female rabbits, aged from 6 –7 months and weighed 3.3 kg in average were used. Animals were divided randomly into three equal groups (10 does each). The 1^st group was served as a control group. The 2^nd, hormonal group, was intramuscularly injected with 25 IU per doe of eCG 48 hours before natural mating. The 3^rd one, algae group, was supplemented with Nannochloropsis oculata powder (2Kg/100Kg diet). In vitro evaluation of early embryonic measurements was conducted on 15 matured rabbit does. Results clearly showed that eCG and algal groups achieved significant (P≤0.05) variances on most of the studied traits compared to control animals. Results showed that conception rates were higher in animals treated with eCG hormone and algae than control (100, 80.33 and 70%, respectively). Overall mean of milk yield during the lactating period decreased by 2.5% in hormonal group, however increased by 39% in algal group, compared to control group. Average total litter weight at weaning had increased by 12.4 and 42.5% in animals treated with eCG hormone and algae, respectively, compared to control. Also, litter size of does at weaning was significantly (P≤0.05) improved in eCG and algae groups by 11.3 and 24.3 %, respectively, compared with control group. On the other hand, the mucin layer was thicker in embryos of eCG hormone and marine algae groups by 13.3 and 39.9 %, respectively, than control. Number of collected embryos had increased in algae group compared with hormonal and control groups (9, 5.5 and 1.4, respectively). Results clearly showed that supplementation of Nannochloropsis oculata at a concentration of 2 kg / 100 kg diet had significantly improved some productive and reproductive performance traits of Hy-plus rabbits. In order to serve as a useful technique, the reproductive performance of using marine algae in feeding of other farm animals need to be addressed