Original Scientific Article
Pregnancy-specific protein B in Yankasa ewes during pregnancy and postpartum periods
Adewale Ayodeji Adeyeye*,
Yusha`u Usman Abubakar,
Olufisayo Oluwadamilare Leigh,
Iyorhembe Utim Ate,
Jashilagari Stephen,
Kabir Ayo Raheem,
Simon Azubuike Ubah

Mac Vet Rev 2021; 44 (1): 55 - 62


Received: 20 August 2020

Received in revised form: 02 December 2020

Accepted: 07 December 2020

Available Online First: 22 January 2021

Published on: 15 March 2021

Correspondence: Adewale Ayodeji Adeyeye, adewale.adeyeye@udusok.edu.ng


Pregnancy-specific protein B (PSPB) is produced by mono and binucleate trophoblast cells in the placenta of ruminants during pregnancy. This study was designed to determine the pattern of serum PSPB in Yankasa ewes during pregnancy and postpartum periods. Mature cycling Yankasa ewes were synchronized and divided into two groups A (n=11) and B (n=13). Group A was bred, while group B was unbred. Blood samples for PSPB assessment were collected from the ewes starting from the day of breeding until 4 weeks post-lambing. All pregnant Yankasa ewes lambed with singleton lambs after an average of 151.18 days. There was a significant (p<0.05) increase in PSPB in pregnant compared with the non-pregnant ewes in the period between 3 weeks post-breeding and 3 weeks post-lambing. Peaks were detected in the first (100.60 ng/ml), second (133.90 ng/ml), and third (114.82 ng/ml) trimesters at 5, 10 and 21 weeks of gestation, respectively, but steadily decreased within 4 weeks (2.38 ng/ml) postpartum. In conclusion, PSPB detected pregnancy in Yankasa ewes from 3 weeks post-breeding with peak levels at 5, 10 and 21 weeks post-breeding in the first, second, and third trimesters, respectively. PSPB decreased gradually after lambing until 4 weeks postpartum.

Keywords: pregnancy specific protein-B, pregnancy, postpartum, Yankasa ewes


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© 2021 Adeyeye A.A. This is an open-access article published under the terms of the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. 

Conflict of Interest Statement

The authors have declared that no competing interests exist

Citation Information

Macedonian Veterinary Review. Volume 44, Issue 1, Pages 55-62, e-ISSN 1857-7415, p-ISSN 1409-7621, DOI: 10.2478/macvetrev-2021-0010, 2021