Does advanced age affect reproductive variables, semen composition, and liquid semen storage during different seasons in Boujaâd rams?

The present research was conducted to evaluate the effects of season and age on scrotal circumference (SC), semen characteristics, semen composition, and sperm motility during liquid storage in Boujaâd rams. Semen was collected throughout 1 year from April 2014 to March 2015. Two ram groups, namely older rams including animals aged 5.5 to 6 years of age, and younger rams including animals aged 2.5 to 3 years of age were used. Scrotal circumferences, semen characteristics, and some biochemical variables from semen were measured. After collection and evaluation, the semen was extended in skim milk (SM) at 15 °C to a concentration of 0.8 × 109 spermatozoa/ml. Thereafter, samples were evaluated at different storage times (0, 8, and 24 h). The results indicate that older rams had greater values of SC, lesser semen quality, protein, lipid, and cholesterol concentrations than younger rams. Nevertheless, for both groups there were the least values for semen quality and semen composition in winter. The semen collected from younger rams had greater motility after liquid storage compared with that of the older rams. The least semen quality after liquid storage was recorded in the winter compared with the other seasons of the year for both age groups. In conclusion, results of the present study indicate that older Boujaâd sheep have lesser semen quality, different semen composition than younger rams after liquid storage and during different seasons of the year. Furthermore, there was a strong correlation between semen composition and motility of stored ram semen.

Morphometry and depth of inseminating catheter penetration in prolific and non- prolific ewes at different ages: A post mortem study.

The ewe's cervix structure is highly variable among females, which may limit the application of transcervical artificial insemination (TCAI). This work aimed to study the variation in cervix anatomy in two different prolificacy breeds (D'man a prolific and Boujaâd a non-prolific sheep). Reproductive tracts were collected from D'man (n = 64) and Boujaâd (n = 187) females aged between 1 and 4 years. The weight of the uterus, length of the cervix and depth of penetration of the inseminating pipette were recorded. The number of cervical rings was counted and their arrangement graded. The cervix anatomy of D'man ewes differs from that of Boujaâd. The cervix morphology of Boujaâd ewes is more complex compared to D'man ewes; this complexity depends on the age of the ewe. No significant difference was found regarding the depth of penetration of the insemination catheter for the two breeds at 1, 2 and 4 years old (P > 0.05). However, at 3 years old, the highest depth of penetration (P < 0.05) was recorded in D'man ewes. In addition, for both breeds, grade 2 was the most frequent (P < 0.05), and the cervix became less complicated for TCAI with advanced age (4 years old). To conclude, the cervix of D'man ewes is less complex and more favorable to TCAI. In addition, to overcome the complexity of the cervix in Boujaâd sheep, a selection of 4-year-old ewes will make the penetration of the artificial insemination catheter possible.

Supplementation of ram semen extender to improve seminal quality and fertility rate.

In sheep, artificial insemination serves as an important technique for breed improvement. In this context, genetic material from a small number of superior sires can be used in a large number of females. During this process, the storage of ram sperm may influence the efficiency of artificial insemination. Two main methods are currently used for ram semen storage: liquid storage and cryopreservation. The oxidative stress during the storage process can injure ram sperm and in some cases this leads to irreversible damage at the cellular level. To reduce such negative effects, different preservation protocols, extenders and protective components have been tested to improve ram sperm quality and to achieve greater fertility rates. This review provides an overview of the recent progress in extender supplementation using antioxidants and other compounds to improve ram semen quality parameters and fertility rates. It will emphasize on enzymes, vitamins, amino acids, proteins, some plant extracts and other compounds such as sugars, seminal plasma and fatty acids that can be used to supplement the extenders to reduce the formation of oxidants in ram semen and maintain its quality and enhance its fertility. It will also stress on how these supplements act, what were the tested levels giving beneficial effects on motility, viability, plasma membrane integrity and DNA fragmentation in liquid, cooled and post-thawing semen?

Effect of season on scrotal circumference, semen characteristics, seminal plasma composition and spermatozoa motility during liquid storage in INRA180 rams.

The present study was undertaken to assess the effect of seasons on scrotal circumference, semen characteristics, seminal plasma composition, and sperm motility during liquid storage of INRA180 rams. The semen was collected from five mature INRA180 rams (2-3 years of age) during one year (from April 2014 to March 2015). Scrotal circumferences, semen characteristics, some biochemical parameters of seminal plasma were evaluated. Immediately after collection and evaluation, the semen was pooled and extended in skim milk (SM) at 15°C to reach 0.8×109 spermatozoa/ml. Thereafter, samples were evaluated at different storage times (0, 8, and 24h). The results showed that scrotal circumference, semen quality and the concentration of total protein in seminal plasma were relatively constant during the year (P>0.05). However, total lipid and cholesterol concentrations increased significantly (P<0.001) in winter and summer. The result showed also that progressive motility was higher in winter and summer after 24h of storage (P<0.01). In contrast, no difference was recorded regarding total motility (P>0.05). To conclude, the INRA180 rams have the ability to produce semen with high quality all over the year. The only parameters showing seasonal variations are cholesterol, total lipid, and progressive motility.

Protective effects of Opuntia ficus-indica extract on ram sperm quality, lipid peroxidation and DNA fragmentation during liquid storage.

The present study aimed to assess the phenolic composition of the acetone extract from Opuntia ficus indica cladodes (ACTEX) and its effects on ram semen variables, lipid peroxidation and DNA fragmentation during liquid storage at 5°C for up to 72h in skim milk and Tris egg yolk extenders. Semen samples from five rams were pooled extended with Tris-egg yolk (TEY) or skim milk (SM) extenders containing ACTEX (0%, 1%, 2%, 4% and 8%) at a final concentration of 0.8×109 sperm/ml and stored for up to 72h at 5°C. The sperm variables were evaluated at different time periods (8, 24, 48 and 72h). Sperm total motility and viability were superior in TEY than in SM whereas the progressive motility, membrane integrity, abnormality and spontaneous lipid peroxidation were greater in SM compared to TEY (P<0.05). The results also indicated that the inclusion of 1% ACTEX in the SM or TEY extender increased the sperm motility, viability, membrane integrity, and decreased the abnormality, lipids peroxidation up to 72h in storage compared to control group. Similarly, even at 72h of storage, 1% ACTEX can efficiently decrease the negative effects of liquid storage on sperm DNA fragmentation (P<0.05). In conclusion, SM and TEY supplemented with 1% of ACTEX can improve the quality of ram semen. Further studies are required to identify the active components in ACTEX involved in its effect on ram sperm preservation.