Expression of ovSOLD1 and caSOLD1 mRNA. (A) Expression of ovSOLD1 and caSOLD1 mRNA in ovine and caprine tissues, respectively. Heart, liver, lung, spleen, kidney, ovary, oviduct, uterus, placenta, testis, seminal vesicle and prostate were used for reverse transcription polymerase chain reaction (RT--PCR) amplification in sheep tissues. Heart, liver, lung, spleen, kidney, ovary, uterus and placenta were used for RT--PCR amplification in goat tissues. Ovine and caprine placental tissues taken at days 45 and 50 of gestation were used, respectively. GAPDH expression levels in ovine and caprine tissue are presented as loading controls. (B) Expression of SOLD1 in ruminant placental tissues by quantitative real-time PCR analysis. i) ovSOLD1 expression during the early to late stages of pregnancy. Ovine samples were recorded as Day 45PTM, Day 45ICOT, Day 95PTM, Day 95ICOT, Day 135PTM and Day 135ICOT, respectively. ii) caSOLD1 expression during the early to late stage of pregnancy. Caprine samples were recorded as Day 50PTM, Day 50ICOT, Day 90PTM, Day 90ICOT, Day 140PTM and Day 140ICOT, respectively. PTM and ICOT refer to placentome and intercotyledonary membrane, respectively. Expression levels of these mRNAs were normalized to that of GAPDH measured in the corresponding RNA preparation. Values are shown as the mean ± SEM. Values with different letters are significantly different (P < 0.05).