Active immunization of the cow against oestradiol-17β

in Reproduction
Authors:
T. E. Martin
Search for other papers by T. E. Martin in
Current site
Google Scholar
PubMed
Close
,
D. M. Henricks
Search for other papers by D. M. Henricks in
Current site
Google Scholar
PubMed
Close
,
J. R. Hill Jr
Search for other papers by J. R. Hill Jr in
Current site
Google Scholar
PubMed
Close
, and
N. C. Rawlings
Search for other papers by N. C. Rawlings in
Current site
Google Scholar
PubMed
Close
Free access

Sign up for journal news

Summary. Six beef heifers were immunized over a 4-month period with an oestradiol-17β–BSA conjugate in Freund's adjuvant. There was an interference with oestrus in the treated heifers; 2 ceased to exhibit oestrus, one exhibited one oestrus and three exhibited oestrus after Day 47 of treatment. The control heifers treated with Freund's adjuvant had normal oestrous cycles. The antiserum titre rose in all treated heifers and attained its highest level in the 2 animals in which oestrus did not recur. The temporal changes in plasma LH, progesterone and oestradiol were normal during the pretreatment period, but became abnormal during the 120 days after immunization. Although plasma oestradiol-17β rose at the expected time of oestrus after treatment, it was apparently effectively neutralized by the antiserum induced by treatment as evidenced by the absence of an LH surge. Plasma progesterone levels fell to baseline and remained low, indicating lack of formation of corpora lutea.

 

  • Collapse
  • Expand