Prediction of fertility by centrifugal countercurrent distribution (CCCD) analysis: correlation between viability and heterogeneity of ram semen and field fertility

in Reproduction
Authors:
R Perez-Pe
Search for other papers by R Perez-Pe in
Current site
Google Scholar
PubMed
Close
,
JI Marti
Search for other papers by JI Marti in
Current site
Google Scholar
PubMed
Close
,
E Sevilla
Search for other papers by E Sevilla in
Current site
Google Scholar
PubMed
Close
,
M Fernandez-Sanchez
Search for other papers by M Fernandez-Sanchez in
Current site
Google Scholar
PubMed
Close
,
E Fantova
Search for other papers by E Fantova in
Current site
Google Scholar
PubMed
Close
,
J Altarriba
Search for other papers by J Altarriba in
Current site
Google Scholar
PubMed
Close
,
JA Cebrian-Perez
Search for other papers by JA Cebrian-Perez in
Current site
Google Scholar
PubMed
Close
, and
T Muino-Blanco
Search for other papers by T Muino-Blanco in
Current site
Google Scholar
PubMed
Close
View More View Less
Free access

The prediction of the fertilizing ability of a sire or a given insemination dose is a primary aim in the field of artificial insemination. Centrifugal countercurrent distribution analysis (CCCD) was used to determine the relationship between some sperm parameters and the in vivo fertility rate obtained with the same sample after cervical artificial insemination. A total of 522 ewes from 26 different farms was inseminated with 53 ejaculates obtained from 25 mature Rasa aragonesa rams. Semen was diluted to 1.6 x 10(9) cells ml-1 and doses of 0.25 ml were prepared and kept at 15 degrees C until used for insemination. The same ejaculates were used for analysis of standard semen parameters and CCCD analysis. Sperm motility, concentration and viability were determined before and after CCCD. Post-CCCD parameters were derived from the analysis of the profile obtained after CCCD. The recovered viability showed the highest correlation with fertility, especially in the central chambers (V2), r = 0.415, P < 0.005). The ejaculate heterogeneity also showed a positive correlation with field fertility (r = 0.23), with a tendency towards significance (P < 0.1). The mean fertility value of all ejaculates used in this study was 46.75%, ranging from 12.5% to 75.0%. Ejaculates were classified into two categories according to their fertility: higher and lower than the mean value. Only the viability recovered in the central chambers (V2) was a parameter with a predictive capacity to discriminate between the two groups (P < 0.05). A predictive equation for field fertility with a correlation coefficient r = 0.488 and a very high level of significance (P < 0.005) was deduced by multiple analysis: PF = 6.02 + 0.069V2 + 0.315H (where PF is predictive fertility, V2 is the recovered viability in the CCCD profile central chambers and H is heterogeneity).