Pregnancy-associated glycoprotein concentrations during early gestation in pregnant Awassi sheep

Abstract

This study was aimed at determining the serum pregnancy-associated glycoprotein (PAG) profile of pregnant Awassi sheep during early gestation. A total of 122 Awassi ewes were used, which were in days 28-56 (28, 30, 32, 36, 42, 49, and 56) of gestation. Blood samples were taken via jugular venepuncture. Out of these animals, 104 ewes that had delivered (singleton lambs, n = 60; twin lambs, n = 44), according to lambing records, were selected for the assessment of serum PAG levels. The serum PAG level was measured using a commercial enzyme-linked immunosorbent assay (ELISA) kit (IDEXX Bovine Pregnancy Test). Whereas serum PAG levels (mean ± standard error) on days 28, 30, 32, 36 and 42 of gestation were found to be similar (0.237 ± 0.031, 0.402 ± 0.067, 0.329 ± 0.036, 0.397 ± 0.075, and 0.409 ± 0.060, respectively), the levels measured on days 49 and 56 of gestation were significantly higher (0.712 ± 0.088 and 0.798 ± 0.115, respectively) (p < 0.05). The serum PAG levels of the twin-pregnant ewes on days 28, 30 and 42 of gestation were higher than those of the singlepregnant ewes (twin-pregnant ewes: 0.314, 0.648 and 0.594, respectively; single-pregnant ewes: 0.186, 0.258 and 0.308, respectively; p < 0.05). With a cut-off sample minus negative (S–N) value set at > 0.300, the sensitivity of serum PAG level-based pregnancy diagnosis was 51.95% between days 28 and 42 of gestation and 92.69% between days 49 and 56 of gestation. On the other hand, with a cut-off S–N value set at > 0.100, the sensitivity of the PAG ELISA test was 94.81% between days 28 and 42 of gestation and 100% between days 49 and 56 of gestation. In conclusion, the serum PAG levels of the pregnant Awassi sheep remained similar between days 28 and 42 of gestation, but progressively increased thereafter. The serum PAG levels of the twin-pregnant Awassi ewes were significantly higher than those of the single-pregnant sheep on days 28, 30 and 42 of gestation, but they were not different on days 32, 36, 49 and 56 of gestation.

Serum pregnancy–associated glycoprotein profiles during early gestation in Karya and Konya Merino sheep

“…Previous studies have reported that serum PAGs and PSPB levels determined with the RIA and sheep ELISA methods were higher in multiple pregnant ewes, compared to singleton pregnant ewes (Akkuş & Yaprakcı, 2022 ; El Amiri et al., 2014 , 2015 ; Ranilla et al., 1997 ). However, the differences observed in the serum PAGs levels of singleton and multiple pregnant ewes measured with bovine PAG‐ELISA pregnancy tests do not change the results of pregnancy diagnosis (Akköse et al., 2021 ; Alkan et al., 2020 ).…”

“…Depending on the breed, plasma PAGs levels have been reported to alter during pregnancy (Milisits‐Németh et al., 2018 ; Redden & Passavant, 2013 ; Ranilla et al., 1994 ). In previous research conducted in Türkiye, the early pregnancy serum PAGs levels of ewes of the Konya Merino (Kaplan et al., 2018 ; Uçar et al., 2018 ) and Awassi (Akköse et al., 2021 ) breeds, both of which are commonly raised in the country, have been monitored. This study was aimed at the comparative assessment of the early pregnancy serum PAGs profiles of Karya ewes, characterized by high milk production and fertility, and Konya Merino ewes, bred for meat and wool production.…”

“…the Konya Merino(Uçar et al, 2018), Awassi(Akköse et al, 2021;Akkuş & Yaprakcı, 2022), Awassi X Merino crossbreed(Karen et al, 2003), German Blackheaded Mutton (GBM), Rhoen X GBM X Dorper crossbreed(Ledezma-Torres et al, 2006), Sarda X Lacaune crossbreed(De Carolis et al, 2020) and Corriedale and Ile de France X Texel crossbreed(Rovani et al, 2016), the serum PAG1 levels of the Polypay X Dorset crossbreed(Roberts et al, 2017) and the serum PSPB levels of the Awassi(Akkuş & Yaprakcı, 2022) and Yankasa(Adeyeye et al, 2021) with minor differences. The steady increase in the level of PAGs as pregnancy advances appears to be associated with increased PAGs production in the binucleate cells of the placenta.…”

Evaluating estrus synchronization and early pregnancy detection in Ossimi sheep: The influence of fluorogestone acetate treatment duration and dosage

“…During the gestation period, the mononucleate and binucleate cells of the ruminant trophectoderm generate pregnancy-associated glycoproteins (PAGs), which originate from the placenta ( Sousa et al, 2006 ). Around day 18 or day 20 following breading, PAGs can be observed in the serum of pregnant ewes ( Barbato et al, 2009 ) and are a reliable indication of pregnancy among ruminants, such as goats ( Singh et al, 2021 ), sheep ( Akköse et al, 2021 ), and cattle ( Silva et al, 2007 ). Progesterone (P 4 ) is a crucial hormone for determining pregnancy in ewes ( Schneider & Hallford, 1996 ).…”