
%0 Journal Article
%A Munro, RK 
%A Bertram, J 
%T Progesterone administered after insemination did not affect the fertility of cattle following a controlled breeding program
%J Australian Journal of Experimental Agriculture
%D 1990/04/01
%V 30
%N 2
%P 179-181
%K 
%R https://doi.org/10.1071/EA9900179
%U https://www.publish.csiro.au/paper/EA9900179 
%X Oestrus and ovulation were induced in 112 suckled beef cows following intravaginal administration of progesterone (CIDR-B) and pregnant mare serum gonadotrophin (PMSG). Supplementary progesterone was provided during the induced luteal phase by re-treatment with CIDR-B from 6-21 or 10-21 days after initial insemination. A control group did not receive supplementary progesterone Supplementary progesterone did not affect the pregnancy rate to the initial insemination (59%). It did, however, tend to increase the proportion of non pregnant cows detected in oestrus 21-24 days after the initial insemination (17131 v. 3/14, P<0.05), but the fertility of treated and control cows inseminated at this second oestrus was not significantly different (30%). 
