title: Detection of activity similar to that of early pregnancy factor after mating sows with a vasectomized boar.
abstract: Incubation of normal pig lymphocytes in serum samples collected from 10 sows immediately before, and at daily intervals after mating with a vasectomized boar significantly elevated the rosette inhibition titre (RIT) of a standard antilymphocyte serum in 6 animals on the first but not on the 2nd and 3rd day after copulation. Infusion of seminal plasma without mating into 5 sows induced an obvious, but not statistically significant, transient rise of titres in 3 pigs. Neither sodium chloride infusion (N = 5), nor sham copulation with diverted penis (N = 5) influenced serum RITs. Porcine seminal plasma showed an inherent rosette-inhibiting property. A depression of rosette formation was evident in a concentration-dependent fashion up to a dilution of 1 in 320. Similarly, preincubation of lymphocytes in serial dilutions of seminal plasma in a non-pregnancy serum sample led to an amplification of the rosette inhibiting capacity of the antilymphocyte serum. Non-specific activation of the eggs to release a signal which induces the production of early pregnancy factor (EPF) or the resorption of seminal plasma components into the blood circulation are considered as possible explanations for the EPF-like activity after mating with a vasectomized boar.
mesh_terms: D000818:Animals; D018835:Chaperonin 10; D003307:Copulation; D005260:Female; D006385:Hemagglutination Inhibition Tests; D007166:Immunosuppressive Agents / Q000097:blood*; D008297:Male; D010455:Peptides; D011257:Pregnancy Proteins; D012397:Rosette Formation; D012661:Semen / Q000502:physiology; D013491:Suppressor Factors, Immunologic; D013552:Swine / Q000097:blood*; D014659:Vasectomy
chemical_list: D018835:Chaperonin 10; D007166:Immunosuppressive Agents; D010455:Peptides; D011257:Pregnancy Proteins; D013491:Suppressor Factors, Immunologic; C025124:early pregnancy factor