Effect of C-phycocyanin purified from Spirulina platensis on cooled ram semen quality and in vivo fertility.

This research sought to purify C-phycocyanin (C-PC) from Spirulina platensis and investigate its potential in enhancing the quality parameters and in vivo fertility of ram semen subjected to cooled storage at 5 °C, when using a skim milk (SM) based semen extender. The purification process of C-PC involved cold maceration, pre-purification using chitosan and activated charcoal, followed by purification through aqueous two-phase extraction (ATPE) and ion-exchange chromatography. Afterward, fifty ejaculates were collected from 4 fertile Boujaâd rams and extended using the SM extender at 37 °C, enriched with 0 µg/mL (control), 1.2 µg/mL, 2.4 µg/mL, 3.6 µg/mL, or 4.8 µg/mL of C-PC. The diluted semen was subsequently cooled to 5 °C using a controlled cooling process, with a gradual cooling rate of approximately 0.5 °C per minute, and its quality parameters were evaluated after 0, 4, 8, and 24 h of cooling storage. Then, its fertilization ability after 4 h of cooling storage was evaluated using artificial insemination. The adopted purification process yielded a grade analytical purity of 4.06. Additionally, semen extended in SM with a 2.4 µg/mL C-PC supplement displayed significant (P < 0.0001) enhancement in total motility, progressive motility, curvilinear velocity, straight-line velocity, average path velocity, viability and lipid peroxidation of ram semen at 0, 4, 8, and 24 h of cooling storage. These improvements were observed in direct comparison to both the control group and the other C-PC concentrations. Regarding fertility rates, semen extended in SM with a 2.4 µg/mL C-PC recorded a 76 % rate, a notable increment from the 63 % observed in ewes inseminated by semen extended in SM alone, although the difference was not statistically significant (p > 0.05). These findings underscore the promising potential of C-PC as a natural supplement for enhancing semen quality, warranting further investigations.

Comparative evaluation of Duragen® and skim milk extenders to enhance ram semen quality and fertility: A promising alternative in ovine artificial insemination.

This study aimed to investigate the effectiveness of Duragen® and skimmed milk (SM) extenders on the quality parameters, bacterial load and fertilization ability of stored ram semen. A total of 50 ejaculates from Sardi rams (n = 5) aged 2.5-3 years, were collected and stored in Duragen® and SM at 15°C. The motilities and velocity parameters generated by the CASA system were then evaluated at 0, 8 and 24 h of storage. Afterward, bacterial loads of sperm extended in Duragen® and SM were determined at 0, 5 and 24 h of incubation. In addition, ewes (n = 100) aged 2 years, have been chosen in the same herd. The selected ewes were then synchronized and inseminated using semen extended in Duragen® and SM and stored for 5 h at 15°C. The results revealed that total and progressive motilities, straight velocity (VSL), straightness (SRT), lateral head displacement (ALH) and beat cross frequency (BCF) were not affected by the extender type after 24 h of storage (p > .05). However, curvilinear velocity (VCL), velocity average path (VAP), linearity (LIN) and wobble (WOB) showed higher values in Duragen® compared with SM extender after 24 h of storage (p < .05). Bacterial loads were observed mainly in sperm stored in SM at 5 h (183 UFC/mL) and at 24 h (357 UFC/mL) of incubation. However, the only case showing a bacterial load in Duragen® is when the storage time attains 24 h (199 UFC/mL). Concerning fertility, sperm diluted in both extenders resulting in high fertility rates which reaches 66% and 73% for Duragen® and SM, respectively, with no statistical difference (p > .05). In summary, Duragen® extender decreased bacterial load in stored semen and maintained high ram sperm quality and fertility. These findings suggest that Duragen® extender could be used as SM alternative in ovine artificial insemination (OAI).