Abstract
Male chickens belonging to three Italian
purebreds \u2013 Ermellinata di Rovigo (ER),
Robusta lionata (RL) and Robusta maculata
(RM) \u2013 were studied. All the birds were reared
under the same rearing conditions (from May
until autumn). Chickens were reared under
infra-red lamps from birth until 4 weeks of age
with a 24L:0D photoperiod. Then they were
kept outdoor: the photoperiod changed according
to the season (from 16L:8D to 12L:12D). At
138 and 168 days of age 20 birds/breed were
weighed and then slaughtered. Testicular samples
were collected, after evisceration,
processed and embedded in paraffine wax.
Sections were stained for morphological observations,
observed with light microscope, and
then classified according to the testis maturation
stage. Ermellinata di Rovigo chickens
showed the lowest (P<0.01) body weight and
the highest (P<0.01) testes weight; testes
maturity was higher (P<0.01) in ER than in
RL, whereas RM was intermediate. For each
genotype testes weight and testes maturity did
not significantly differ with aging.
Correlations between testes weight and body,
comb, and wattles weight, according to the
breed, were calculated at 168 days of age. For
ER no significant correlation was found,
whereas RL showed a significant (P<0.01)
positive relationship between testes weight
and body weight, and sexual secondary characters.
Robusta maculata showed a significant
correlation between testes weight and comb
(P<0.01) and wattles weight (P<0.10). Our
results suggest that under the studied environmental
conditions ER showed the highest
testes development according to its more precocious
achievement of adult body weight,
whereas RL was the least precocious purebred
