The present study demonstrate the relationship among physical reproductive characters and
semen quality parameters at different age groups of Sahiwal bulls. The standard breeding
soundness evaluation criteria is not set for the screening of Sahiwal bulls. Artificial insemination
is a tool for rapid genetic improvement. Sahiwal bulls used as AI sire should be screened through
standard breeding soundness evaluation criteria. Therefore the present study has been designed to
determine objectives like: (1) to determine the relationship among physical reproductive characters
and semen quality parameters at different age groups of Sahiwal bulls (2) to compare the semen
quality parameters of pendulous with non-pendulous Sahiwal bulls. The study was carried out
during July-October 2016 at Semen Production Unit Qadirabad district Sahiwal. The Sahiwal bulls
(n=91) maintained at SPU as a regular semen donor bulls, having no reproductive disorder were
selected for this study. These bulls were divided into four different age groups G1 (24-48 months,
n=8), G2 (49-72 months, n=50), G3 (73-96 months, n=27) and G4 (97-108, n=6). The evaluation
of the bulls were done for BW, SC and DPS. Semen quality parameters (ejaculate volume, sperm
concentration, motility, percent live sperm and morphological abnormalities) were evaluated and
compare between different groups. Mean BW and SC increases (P˂ 0.05) with the age of bulls,
but DPS is not correlated with the age means it does not increases with the age. Ejaculate volume
(3.58±0.1, 3.92±.05, 3.97±.06, 4.24±0.15 ml), sperm concentaration (870.6±14.1, 897.4±6.5,
899.5± 8.0, 856.9±20.2 x 10x6 /ml) increases with age. However motility remain more or less
unchange with age . The percentage of live sperms were 75.06±0.3, 75.75±0.1, 75.96±0.1,
77.09±0.4 respectively and percentage of morphological abnormalities were
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19.57±0.6,17.61±0.2,15.80±0.2,16.69±0.4 repectively. The morphological abnormalities were
higher in younger bulls as compered to older bulls. It can be concluded that the BW, SC, ejaculate
volume, sperm concentration (except in G4 due to small sample size) increases as that the age
increases, whereas the other semen quality parameters like individual motility, motility after
dilution and individual motility after freezing looks to be more or less independent of age. The
DPS is not correlated with the age, it may be a genetic character. In comparison of semen quality
between pendulous and non-pendulous bulls, the ejaculate volume and sperm concentration were
significantly higher in pendulous bulls instead of non-pendulous bulls (in G2 and G3) and nonsignificantly
higher (in G1 and G4). While comparing the other semen parameter like motility
percentage (individual, after dilution and after freezing) between pendulous and non-pendulous
bulls the results remain non-significant. The findings of this study direct us to focus more on nonpendulous
bulls instead of pendulous bulls, the reason behind that is the pendulous bull’s needs
extra managemental care as they are more prone to injuries and perpetual infections. These
findings could be used to set the selection criteria for Sahiwal bulls.