Reproduction in Domestic Animals - Facultad de Ciencias Veterinarias

16 t h International Congress on Animal Reproduction
124 Poster Abstracts
similar to or even below baseline values. The collected data suggest a
significant and so far not recognized influence of spermatozoa on the
regulation of the uterine immune responses after insemination.
P291
Effect of dietary supplementation with salmon oil on
cryopreservation of boar semen
Amorim, LS 1, Torres, CAA 2 *, Amorim, EAM 2 , Graham, J 2
1Department of Biomedical Sciences, Colorado State University, Fort Collins,
CO, United States; 2 Animal Science Department, Federal University of
Viçosa, Minas Gerais, Brazil
Cryopreservation of boar semen is not common, as the damage caused
to the cells is extensive. The fatty acid composition of boar
spermatozoa contain some docosapentaenoic acid (DPA) and
docosahexaenoic acid (DHA). The increase in the freezability of boar
spermatozoa by enhancing the DHA content of the plasma membranes
via changes in the lipid content of the feed is considered. The
objective was to find out whether DHA, given as salmon oil
supplementation, may have a beneficial effect on cryopreservation of
boar semen. Twenty-four boars Dalboard 85, 1–2 years old, were
distributed in a completely randomized factorial design (2×3) with
two oil sources (soybean and salmon) and three levels of antioxidant
(150, 300, and 450 mg of vitamin E/kg). The diets consisted of a basal
diet that was supplemented with 35g soybean or salmon oil (SO) per
kg diet. During a period of 10 weeks of feeding the diets, one
ejaculate from each boar was collected per week. An aliquot of the
sperm rich fraction was diluted 1:1 (v:v) in BTS and used for
assessment of fresh semen quality and sperm lipid analysis. Semen
was diluted with BTS at 30 o C and after kepted at 24 o C for 1 h, and
then, centrifuged with centrifugation diluent (CD) and rediluted with a
freezing extender (50 ml of 11% lactose in distilled water + 20 ml of
egg yolk, + 25 ml of CD, 1.5 ml Equex, 6 ml of 85% glycerol) to a
final concentration of 500x106 cells/ml and filled French straws (0.5
ml; Minitub, Brazil) and stored for 1 h at 5 oC. After, samples were
frozen 5 cm above liquid nitrogen. Thawing was in a noncirculating
water-bath 37 o C for 20s. For determining the fatty acid composition
of the spermatozoa, a sample of approximately 15 ml was taken from
each ejaculate shortly after collection and centrifuged for 20 min at
1000 x g. The remaining semen was frozen until analysed. Sperm
motility, morphology and lipid composition were assessed in fresh
and frozen–thawed samples. The DHA increased in the SO-group
from 23.3 to 46.7% and the DPA decreased from 11.5 to 5.2%
(P