Impacts of Enzymes and Probiotic in Improving the Utilization of Sieved Olive Pulp Meal on Reproductive Performance and Some Blood Traits of Rabbit Bucks

Abstract

live pulp is considered a waste of agricultural processing with low nutritional value. The current study aimed to study the effect of enzymes and dry yeast in enhancing the benefit of sieved olive pulp (SOP) on reproductive performance and some blood parameters of rabbit bucks. The question arises as to what is the maximum amount of sieved olive pulp that can be incorporated into a buck's diet to achieve maximum benefits using some additives? A total of 49 adult V-Line buck rabbits were divided into seven dietary treatments and housed in individual batteries. Treatments included a basal diet with no supplement as a control and the other six treatments involved substituting the basal diet with two levels of 20 and 25% of SOP supplemented with 0.1 g/kg econase enzymes (E), 0.5 g/kg dry yeast (DY), or a combination of E+DY for 8 weeks. The results showed that rabbit bucks fed diets containing SOP20-E and SOP25-DY exhibited significant improvement (P≤0.05) in viability compared with other treatments, as well as those feeding rabbit bucks diets containing SOP25 with any supplements resulted in significant improvements (P≤0.05) in sperm concentration as compared to other groups. While bucks received SOP diets with any supplements, there was a significant (P≤0.01) increase in total sperm output compared with the control group. Additionally, the inclusion diet SOP25-DY produced the fewest abnormal sperm and dead spermatozoa in comparison to other treatments. Supplementations or SOP levels did not significantly impact the majority of hematological parameters, but platelets were significantly (P≤0.05) lower in all dietary treatments than the control group. Blood cholesterol levels were significantly (P≤0.01) lower in rabbit bucks that received SOP, regardless of supplementation compared to the control group. Conversely, diets containing SOP20 or SOP25 with E+DY resulted in a statistically significant increase in glucose levels (P ≤0.01). In conclusion sieved olive pulp can be integrated into buck's diet up to 25% supplemented with enzymes or dry yeast without any negative effects on some semen quality, blood constituents or hematological parameters.