There is evidence from the distant past which suggests that when
cloprostenol is used to induce luteal regression in ewes undergoing
superovulatory treatment, the CL subsequently formed regress prematurely
after about 5 days. Sorry I can't help with a reference. Neil Beck

>Does any one have information, published or unpublished, on possible
>effects of treatment of ruminants with the prostaglandin F2 alpha 
>analogue cloprostenol on the development and function of the corpus 
>luteum formed from the subsequent ovulation ?
>
>Similarly, does any one have thoughts on possible mechanisms by which 
>treatment of ruminants with cloprostenol can affect the development 
>and function of the subsequent corpus luteum ?
>
>This is unlikely to be due to the direct action of cloprostenol due to 
>its half-life and removal of tissue residues within 72 hours - cows 
>(Reeves, Journal of Agricultural and Food Chemistry, 1978, 26, 152-
>155).
>---------------------------------------------------------------------
>Background
>During an immunohistological study of the development of the luteal 
>extracellular matrix of cows (slaughterhouse - presumed natural 
>cycles) and ewes (cloprostenol synchronized), differences were noted 
>regarding the pattern of collagen type I accumulation. On the basis 
>of another study on cows treated with cloprostenol it was felt that 
>the differences were not species differences and were due to the 
>treatment.
>
>I know of three papers noting reduced progesterone levels in Brahman, 
>Brown Swiss and Simmental cows:
>Cardenas et al, Animal Reproduction Science, 1991, 26, 211-218 
>Hansen et al, Journal of Animal Science, 1987, 65,524-533 
>Hardin and Randel, Theriogenology, 1982, 17, 669-675
>
>Any thoughts ?
>
>Regards
>
>Mr Leigh Silvester
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>Department of Physiology &                           tel: 0115 951 5151
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>LEICS   LE12 5RD                                                    
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