Three distinct studies using an ethidium bromidedigitonin
fluorometric assay were conducted to determine
if the fertilizing ability of individually caged broiler
breeder males (BBM) could be enchanced by nutrition,
breeding and semen extender viscosity.
The first study evaluated the effects on the
spermatozoal quality of BBM by feeding corn-soybean meal
(CS) and corn-yellow pea (CYP) diets containing 16% crude
protein (CP) fed on a daily restricted basis and the 7% CP
fed ad libitum. The study was conducted from 30 to 43
weeks of age (WOA). Under the conditions of this study,
feeding the diets containing CS and CYP did not have
detrimental effects on spermatozoal cell characteristics,
fertilizing ability and hatchability of fertile eggs. This
study demonstrated that BBM kept in cages could be fed
yellow peas as well as 77. CP diets.
In the second study, BBM were divergently selected
for a spermatozoal cell viability index score for three
generations. Semen was collected and evaluated in each
generation for semen viability, fertilizing ability and
hatchability of fertile eggs. No differences (P>.05) were
observed between the divergently selected lines in both
generations (61 and 02) for the semen characteristics
evaluated. Attempts to explain the lack of response to
divergent selection were discussed.
The third study attempted to decrease the
conventional insemination dose of 100 x 10⁶ spermatozoal
cells to 33 x 100⁴ per hen by increasing the viscosity of
Beltsville Poultry Semen Extender (BPSE) by the addition
of 47. (w/v) carboxymethylcellulose (CMC). The fertility at
the lower insemination dose was not enchanced by
increasing the viscosity. When the data was arranged
according to the insemination dose and fertility was
evaluated over the first seven days of the fertile egg
collection period, no difference was observed (P<.05)
according to the insemination dose. Therefore, the cost of
maintaining the BBM could possibily be reduced by using 33
x 10⁶ sperm cells for artificially insemination under the
field conditions
