- One group of four adult White Leghorn male chickens was fed a
diet containing 7.3% linoleic acid and 32.4 mg/ kg of added vitamin E
(group IV) for 50 weeks which was designated as the positive control.
A second lot (group I) containing 14 males received the same level of
linoleic acid but no added vitamin E until the 34th week when four
males (group III) having the lowest fertility based on the results of
the 29th week were transferred to the vitamin E supplemented diet.
At 44 weeks, based on determinations made at the 38th week, the
deficient group was again divided into two groups of five males each,
one retained on the deficient diet (group I) which served as the negative
control, the other (group II) was placed on the vitamin E supplemented
On the basis of first setting data (2nd-9th day after insemination)
fertility of group I, the negative control, decreased to 35.0% at 29
weeks. Fertility of group IV, supplemented throughout the trial with
32.4 mg/kg of vitamin E, was significantly higher than group I
beginning at 24 weeks and throughout the remainder of the experiment.
At 50 weeks, fertility of the negative control group had decreased
to 4.2%. Fertility of group III, (3. 3 %), supplemented with 32.4
mg/kg vitamin E at 34 weeks, and group II, (16.2%), supplemented
with the above level of vitamin E at 44 weeks, had increased to
60.6% and 65.4%, respectively, at 50 weeks. At 47 weeks fertility
in all supplemented groups was significantly greater than the negative
No meaningful differences were evident between any group for
semen volume, semen concentration, hatchability of fertile eggs,
feed consumption or body weights. Second setting data (10th through
17th day) for fertility and hatchability of fertile eggs gave results
similar to the first setting, although lower fertility values were
obtained due to the decreased fertility of sperm after nine days in the
oviduct. Insemination of larger volumes of semen from vitamin E
deficient birds did not increase fertility, nor did a reduced volume
of semen from supplemented birds result in decreased fertility.
No conclusive results were obtained from the analyses of
fatty acids in the sperm. It was noted, however, that sperm motility
decreased in vitamin E deficient males.
From these findings one may conclude the following:
1. Male chickens fed diets high in linoleic acid maintained
their fertilizing capacity when supplemented with 32.4 mg/kg of
2. Sterility in male chickens induced by a high linoleic acid and
low vitamin E diet was reversible by supplementation with 32.4
mg/kg of vitamin E, even after prolonged deficiency periods of 34
and 44 weeks duration.
3. Results obtained from the second setting of eggs would
indicate that one eight-day period of collection would be sufficient.
4. Increased volume of semen from deficient birds did not
increase fertility, nor did reduced volume of semen from supplemented
males reduce fertility.
5. Sperm motility was decreased in vitamin E deficient birds.