E. Behalova et al., IN-VITRO FERTILIZATION OF PIG OVA - EFFECTS OF VARIOUS FACTORS ON PENETRATION, POLYSPERMY AND MALE PRONUCLEUS DEVELOPMENT, Animal reproduction science, 32(1-2), 1993, pp. 127-133
Pig zona-free and zona-intact ova were successfully penetrated in vitr
o by ejaculated boar spermatozoa. The oocytes were obtained from antra
l follicles (2-5 mm in diameter) of slaughtered gilts and matured in M
-1 99 with porcine follicular fluid (50%) and follicle stimulating hor
mone (FSH) (0.25 IU ml-1) for 44 h at 38.5-degrees-C. In vitro fertili
sation (IVF) was carried out with a spermatozoa-rich fraction of a fre
sh boar ejaculate which had been incubated in M-199 supplemented by 10
% inactivated bovine serum. The penetration rate of zona-free oocytes
was dependent on the duration of sperm incubation. IVF of zona-intact
ova was designed to estimate the optimal spermatozoa concentration for
insemination. The concentration of (1-1.5) X 10(6) spermatozoa ml-1 g
ave the best fertilisation results (87%), whereas the concentration be
low 1 X 10(6) spermatozoa ml-1 resulted in a lower fertilisation rate
(62%) but in a higher number of monospermic eggs (36%) and male pronuc
leus formation (80%).