The tests on blastogenesis using phytohemagglutinin, pokeweed mitogen and concanavalin-A were conducted with peripheral blood lymphocytes (PBL) obtained from sows treated with oxytocin and prostaglandin F_2α (PG). The results at 0, 30, 60, 90 and 120 minutes were comparatively examined. Six healthy post-weaning sows each weighing between 195 and 300kg were treated with single intravenous injection of 25IU of oxytocin and 10mg of PG.
The results revealed that the sows treated with oxytocin or PG showed significantly lower mitogenic responses of PBL to three mitogens in vivo than those not treated. The results of the in vitro study revealed that direct addition of PG or oxytocin and mitogen to the PBL of intact sows caused significant impairment of blastogenetic responses of lymphocytes of sows treated with PG in comparison with those treated with oxytocin.

View full abstract

In oder to investigate the effects of sex on growth, carcass traits and physico-chemical properties of muscles and adipose tissues, 4 male, 4 castrated male and 6 female pigs crossbred with wild boar were fattened from 30kg to 90kg of body weight.
1) The growth results were significantly better in male and castrated pigs than in female pigs in terms of daily weight gain and total feeding days, while those in male pigs were better than those in castrated male pigs in terms of feed consumption and feed conversion but without significance in the differences.
2) The uncastrated males proved to have less accumulated fat and higher yield of lean meat than those of the others. Our impression on the quality of meat in this conjunction during dressing of meat and test eating was that it had not the smell peculiar to male pigs as would be sensible.
3) There was no appreciable difference among the three different sex groups in terms of chemical composition of muscles and the color shade of M. longissimus thoracis.
4) The fatty acid composition of back fat did not show remarkable difference among the three different sex groups, but the linoleic acid content in kidney leaf fat was significantly higher in male than in castrated male or female.
The above mentioned results suggested that the fattening of male pigs crossbred with wild boar had merit in view of good growth and higher yield of lean meat, especially so when slaughtering is done at a body weight of approx. 90kg, by which the peculiar masculine smell is minimized and the necessity of castration for fattening purpose can be dispensed with.

View full abstract