Buffalo bull semen traits are economically important traits that influence farm fertility and profitability. Genetic improvement
of semen characteristics is an important detail of the genetic improvement. This study was conducted to assess
the relationship between the breeding values as well as the phenotypic values for semen traits (VOL, MM, LS, AS
and CONC) of the Egyptian buffalo bulls. A total of 7761 normal semen ejaculates were collected and characterized at
ILMTC laboratory from 26 bulls from 2009 to 2019. For VOL, MM, LS, AS, and CONC, the actual means were 3.89 mL,
62.37%, 60.64%, 3.94%, and 0.67 × 109 sperm/mL, respectively. The prediction of breeding values for semen traits was
estimated using a Bayesian procedure. The estimated standardized EBVs and phenotypic values were used in the principal
component analysis (PCA). Of five PCs, one PC (PC1) had > 1 eigenvalues that was responsible for 87.19% of the total
variation of SEBV, and two PCs had > 1 eigenvalues that were responsible for 59.61% and 21.35% of the total variation
of the phenotypic values. Together, PC1 and PC2 accounted for 97.97% of the total variance of SEBV and 80.96% of
the total variance of phenotypic values. A graphs of the first two components showed the traits separated into two different
directions by group. This indicates each group was under similar genetic influence. Therefore, selection can be done
separately for each group without influencing the other. Principal component analysis reduced variables to describe the
key information in buffalo semen data. |
