- Email: [email protected]
Production of PMSG antiserum in cattle: Assay of inhibitory activity and use in superovulated heifers
THERIOGENOLOGY
PRODUCTION OF PMSG ANTISERUM IN CATTLE: ASSAY OF INHIBITORY ACTIVITY AND USE IN SUPEROVULATED HEIFERS J. Saumande and D. Chupin I.N.R.A. - Station de Physiologie de la Reproduction 37380 N o u z i l l y , France In animals treated to induce superovulation, PMSG s t i l l present a f t e r ovulation could have a deleterious e f f e c t on the q u a l i t y of embryos by stimulating steroid secretion, The i n j e c t i o n of anti-PMSG antibody would counteract t h i s action. Anti-PMSG antisera were produced in c a t t l e in order to avoid any anaphylactic shock and, in the case of repeated treatments, production of antibodies against foreign immunoglobin. A bull and a cow were immunized by giving I.M. injections of 5,000 i . u . PMSG in Freund's adjuvant. The i n h i b i t o r y a c t i v i t y of the antisera obtained was measured in 23 day old female rats which received concomitantly 20 i . u . of PMSG (S.C.) and d i f f e r e n t d i l u t i o n s of the antisera ( I . P . ) ; the rats were k i l l e d 48h l a t e r and the ovaries weighed, Both c a t t l e produced a n t i PMSG antibody and, a f t e r f i v e injections f o r the bull and seven f o r the cow, I0 ul of serum completely i n h i b i t e d the response to 20 i . u . PMSG. The i n h i b i t o r y a c t i v i t y was also tested in cows. We could find neither a volume of antiserum nor a scheme of i n j e c t i o n which would prevent superovulation of PMSG treated animals. However, when PMSG and antiserum were incubated together before being injected, no superovulation occurred. Despite t h i s negative r e s u l t , the i n j e c t i o n of anti-PMSG antiserum 12h a f t e r the beginning of estrus increased the mean number of good embryos collected per h e i f e r (3.7 vs. l . g in controls) without any e f f e c t on the number of embryos recovered; the number of large f o l l i c l e s was decreased (2.4 vs. 3.5 in controls).
108
JANUARY 1981 VOL. 15 NO. 1
PRODUCTION OF PMSG ANTISERUM IN CATTLE: ASSAY OF INHIBITORY ACTIVITY AND USE IN SUPEROVULATED HEIFERS J. Saumande and D. Chupin I.N.R.A. - Station de Physiologie de la Reproduction 37380 N o u z i l l y , France In animals treated to induce superovulation, PMSG s t i l l present a f t e r ovulation could have a deleterious e f f e c t on the q u a l i t y of embryos by stimulating steroid secretion, The i n j e c t i o n of anti-PMSG antibody would counteract t h i s action. Anti-PMSG antisera were produced in c a t t l e in order to avoid any anaphylactic shock and, in the case of repeated treatments, production of antibodies against foreign immunoglobin. A bull and a cow were immunized by giving I.M. injections of 5,000 i . u . PMSG in Freund's adjuvant. The i n h i b i t o r y a c t i v i t y of the antisera obtained was measured in 23 day old female rats which received concomitantly 20 i . u . of PMSG (S.C.) and d i f f e r e n t d i l u t i o n s of the antisera ( I . P . ) ; the rats were k i l l e d 48h l a t e r and the ovaries weighed, Both c a t t l e produced a n t i PMSG antibody and, a f t e r f i v e injections f o r the bull and seven f o r the cow, I0 ul of serum completely i n h i b i t e d the response to 20 i . u . PMSG. The i n h i b i t o r y a c t i v i t y was also tested in cows. We could find neither a volume of antiserum nor a scheme of i n j e c t i o n which would prevent superovulation of PMSG treated animals. However, when PMSG and antiserum were incubated together before being injected, no superovulation occurred. Despite t h i s negative r e s u l t , the i n j e c t i o n of anti-PMSG antiserum 12h a f t e r the beginning of estrus increased the mean number of good embryos collected per h e i f e r (3.7 vs. l . g in controls) without any e f f e c t on the number of embryos recovered; the number of large f o l l i c l e s was decreased (2.4 vs. 3.5 in controls).
108
JANUARY 1981 VOL. 15 NO. 1