Retrograde flushing of dromedary camel bull epididymis: A lesson learned

Abstract

The post mortem collection of epididymal spermatozoa represents the last chance to preserve the gametes of high valuable animals. Studies on dromedary camel epididymal spermatozoa could be a valuable tool for overcoming obstacles related to semen collection or with the viscous nature of their ejaculates as well as to elucidate the role of seminal plasma in this species. Preliminary studies investigated the collection of camel epididymal spermatozoa obtained through the retrograde flushing (Turri et al., SOAS camel conference 2013). Hence this work aimed at describing the application of this technique, main obstacles found and our obtained results. Nine adult dromedary camel bulls were neutered through general anesthesia and open orchiectomy; testicles were kept in an isolated box, at 4 °C, until reaching the nearest laboratory, after 6–8 h. Epididymides were carefully separated from testicles and cleared from surrounding tissues. The cauda epididymides were separated from the body and the deferens ducts were catheterized through a blunted 32 G needle. Retrograde flushing was performed with a 3 ml syringe using a tris-citrate buffer. After recovery, sperm motility was evaluated by two operators on a minimum on 5 fields, whereas viability and morphology were evaluated by eosin/nigrosine staining. The main difficulties were found with the catheterization of the deferens as well as with the flushing process (improper insertion, rupture of the duct, leaking of buffer from insertion site): out of 18 testicles, 4 attempts completely failed, 4 gave low sperm recovery, and 10 were successful. Semen parameters in low recovery flushings were as follows: total sperm concentration 175 × 106 spz; viability 80.0%; total motility 72.4%; abnormal spermatozoa 20%. On the other hand, in the successful cases, the following parameters were observed: total sperm concentration 720 × 106 spz; viability 88.6%; total motility 78.4%; abnormal spermatozoa 16.2%. Overall, retrograde flushing of dromedary camel epididymides can be performed and after some practice, acceptable semen parameters can be obtained. This technique is a valuable tool for preserving high value germplasm and improving new studies on assisted reproductive technologies in dromedary camels.