Rabbit seminal plasma catalase is much higher than in the semen of other mammals, and
differences appear to be inherited. Because of the scarcity of information on rabbit
blood catalase and haematocrit in Dutch-belted rabbits, an investigation of possible
effects of gender, age and genetics on these variables was undertaken. There were 191
rabbits sampled at 2-3 months, 130 at 12 months and 61 at 18-24 months of age. There
was no age effect on the haematocrit values and on blood catalase activity. At 12
months of age males had an average haematocrit value of 44% compared with 40% for
females (P < 0.05). Corresponding average catalase values were
431 and 356 units/ml of blood (P < 0.05). Also catalase was
measured in the semen and blood of 34 males, and males differed in both their blood
and semen catalase activity (P < 0.05). The correlation between
the two traits was r = 0.44. Heritability (h
2) estimates, based on 231 rabbits were 0.40 for blood catalase activity,
and 0.26 for haematocrit. The genetic correlation between the two variables was 0.83
(P < 0.05). These studies are consistent with the literature
in that female rabbits have a slightly lower haematocrit value than males, and this
is associated with a lower catalase activity. This appears to be the first report of
a study that compares rabbit blood catalase in males and females of different ages.
Preliminary evidence that differences may have a heritable basis is consistent with
previous studies on rabbit semen catalase.
