Improving the reproductive, immunity and health status of rabbit does using honey bee venom

The aim of the present study was to investigate the long-term effect of using bee venom (BV) on the reproductive performance, immune, and health status of rabbit does and its effect on their litters. Sixty mature does, from Spanish V-line rabbit stock, were randomly assigned to four homogeneous groups with 15 does each. The 1^st , 2^nd and 3^rd groups were injected twice weekly under the neck skin with 0.1 ml solution contains 0.1, 0.2 and 0.3 mg BV/rabbit respectively. The 4^th group served as a control group. From the results, litter size at birth, litter weight and survival rate at weaning age as well as milk yield were significantly (p ≤ 0.05) increased in BV groups than in the control group. Serum estradiol 17-β (E2) was significantly (p ≤ 0.05) higher (15%) in the rabbit does treated with BV compared to the control group. The treated does with BV at any study doses showed a gradual and significant (p ≤ 0.05) decrease (12%) in serum progesterone levels (P4) compared to the control. They also showed a significant (p≤0.05) increase in conception (17%) and fertility rates (10%) compared to the control does. Treatment of rabbit does with BV caused a gradual and significant (p ≤ 0.05) reduction in both aspartate aminotransferase (AST) (16%) and alanine aminotransferase (ALT) (37%) liver enzyme activities. Additionally, results have shown that BV resulted in a gradual and significant (p ≤ 0.05) increase in total antioxidant capacity (TAC), antioxidative enzymes such as glutathione S-transferase (GST) and glutathione peroxidase (GPx), serum IgG, IgM and IgA levels with significant (p ≤ 0.05) decrease in malondialdehyde (MDA) and thiobarbituric acid reactive substances (TBARS) in BV groups compared to the control group. Results suggest that BV can be used in rabbit farming as an effective and safe alternative to artificial chemical drugs (sexual-stimulants) to improve certain reproductive traits, immune response and health.

Effect of carbon dioxide during the early stage of duck egg incubation on hatching characteristics and duckling performance

Gaseous exchange is very important for embryonic development during the incubation of bird eggs. The present study was carried out to investigate the effect of carbon dioxide (CO₂) pumping during the first 10 days of Pekin duck egg incubation on hatching characteristics, embryonic growth, hormonal concentrations and the post-hatch weight of the ducks. Two different ventilation conditions were used in this study. In one condition (V), the incubator was ventilated standard. In the other condition (NV), CO₂ was gradually pumped into a non-ventilated incubator to reach and maintain a 1% concentration through the first 10 days of incubation, after which the incubator was ventilated for the rest of the incubation period. The CO₂ percentage in the V incubator was constant at approximately 0.18%; by contrast, in the NV incubator, the concentration was increased gradually from 0.17% to 1%, where it was maintained through the 10th day of incubation. Throughout the incubation period, the egg weight loss and the embryonic mortality percentages were significantly lower in NV than in V. The hatchability of fertile eggs and the weights of ducklings at hatch were significantly higher in NV than in V. The embryonic T₃, T₄ and corticosterone levels in NV were significantly higher than those in V. Additionally, the haematological parameters (haemoglobin, packed cell volume and red blood cells) of the embryos were significantly higher in NV than in V. Furthermore, a total of 1198 ducklings for the V and NV conditions, all one day old, were individually weighed and then transferred into randomly assigned floor pens with 3 replicates for each ventilation condition. The feed conversion ratio of the ducks was significantly lower in NV than in V, while the reverse was true of body weight at different ages. Therefore, we can conclude that the NV condition with circulation of CO₂ for the first 10 days of incubation is preferable to the V condition.