The results of various haemato-biochemical and hormonal parameters in non-pregnant and pregnant groups (6
th, 7
th, 8
th and 9
th weeks) are presented in Table 1 and 2, respectively.
Haematological parameters
Maternal RBC, Hb and PCV decreased progressively with advancing gestation, with significant reductions (P<0.05) during the 8th and 9th weeks. These findings are consistent with reports in cats, dogs, camels and rabbits
(Abdulsalam et al., 2024; Varun et al., 2023; Sukar et al., 2020; Abdul-Rahaman et al., 2018;
Elzein et al., 2016; Şimşek et al., 2015). The decline in erythrocytic parameters likely reflects physiological haemodilution associated with pregnancy
(Abdulsalam et al., 2024). MCV, MCH and MCHC showed significant (P<0.05) variations between pregnant and non-pregnant queens, with increasing progressively and peaking at 9th week. These findings agree with reports in cats and camels (
Abdul-Rahaman et al., 2018;
Şimşek et al., 2015). The increased MCV during late gestation may reflect a compensatory bone marrow response to gestational anaemia
(Abdulsalam et al., 2024).
WBC counts progressively increased with advancing gestation, reaching significantly higher (P<0.05) levels in the 8
th and 9
th weeks, with the highest value at 9
th week. This physiological leukocytosis is consistent with reports in queens and small ruminants
(Abdulsalam et al., 2024; Muthuramalingam et al., 2022; Elzein et al., 2016; Şimşek et al., 2015). The increase may reflect normal gestational adaptation and maternal stress associated with elevated cortisol, although contrasting findings have been reported in Barki ewes (
El-Sayed et al., 2024). Differential leukocyte counts remained statistically comparable between both groups and across gestational weeks, with basophils undetected in all samples. Similar findings were reported in camels and goats
(Shittu et al., 2023; Abdul-Rahaman et al., 2018), indicating stable leukocyte distribution during pregnancy. In contrast, increased neutrophils and decreased monocytes reported in late pregnancy in ewes and goats may reflect hormonal changes and activation of the hypothalamic pituitary adrenal axis (
El-Sayed et al., 2024;
Elzein et al., 2016).
Biochemical parameters
Serum ALT and AST remained unchanged (P>0.05) between both groups and across gestation, indicating no adverse effect of pregnancy on maternal hepatic function. In contrast, ALP increased significantly (P<0.05) during 8
th and 9
th weeks, peaking in the 9
th week, likely due to placental development and increased placental and bone isoenzyme activity rather than hepatic dysfunction. Similar findings have been reported in cats, mares and dogs
(Chikhaoui et al., 2023; Varun et al., 2023; Abdulsalam et al., 2024). Serum glucose concentrations decreased progressively with advancing gestation, showing significant differences (P<0.05) between non-pregnant and pregnant queens during 7
th to 9
th weeks. The lowest glucose level was observed at 9
th week, likely reflecting increased fetal energy demands during late gestation. Similar declines have been reported in cats and small ruminants (
El-Sayed et al., 2024;
Shittu et al., 2023; Şimşek et al., 2015).
Serum total protein concentrations remained unchanged (P>0.05) between both groups and throughout gestation, suggesting effective maternal adaptation to the increased nutritional demands of pregnancy. Similar observations have been reported in cattle
(Boro et al., 2025), whereas declines observed in goats, sheeps and camels have been attributed to increased fetal protein requirements (
El-Sayed et al., 2024;
Abdul-Rahaman et al., 2018;
Elzein et al., 2016). Serum BUN values significantly increased (P<0.05) at the end of gestation, with higher values at 8th and 9th weeks, likely reflecting increased protein metabolism and maternal-fetal nitrogenous waste production, consistent with previous reports in dogs
(Varun et al., 2023). Serum creatinine remained stable throughout gestation but increased significantly (P<0.05) in 9
th week, consistent with findings in cats and dogs
(Varun et al., 2023; Abdulsalam et al., 2014). Higher maternal than amniotic fluid creatinine concentrations suggest effective maternal renal regulation
(Bigliardi et al., 2022), while stable levels in cattle indicate species specific physiological differences
(Metref et al., 2025).
Serum calcium remained relatively stable throughout gestation, with significant differences (P<0.05) only in 7
th and 9
th weeks compared with non-pregnant queens, indicating effective maternal calcium homeostasis despite increasing fetal mineral demands. Phosphorus remained unchanged until the 8
th week but increased significantly in 9
th week, suggesting physiological adjustments in mineral metabolism near parturition. Similar findings have been reported in cats and camels, whereas contrasting phosphorus changes were reported in mares
(Chikhaoui et al., 2023; Abdul-Rahaman et al., 2018;
Şimşek et al., 2015).
Hormonal parameters
Serum progesterone (P4) concentrations differed significantly (P<0.05) between pregnant and non-pregnant queens and across gestational weeks. P4 gradually declined from 6th to 9
th week, which is consistent with previous reports
(Termelioğlu et al., 2022; Keiser et al., 2017; García Mitacek et al., 2015). Higher P4 levels in pregnant queens highlight its essential role in pregnancy establishment and maintenance. Serum cortisol differed significantly (P<0.05) between pregnant and non-pregnant queens during 6
th to 8
th weeks, but not at 9
th week. Within pregnant queens, cortisol remained comparable from 6
th to 8
th weeks but increased significantly at 9
th week. This late gestational rise agrees with reports in dogs (
Artusi, 2016;
Concannon et al., 1978). Similar prepartum increases have also been reported in large and small ruminants, associated with fetal maturation and preparation for parturition
(Vala et al., 2019; Shittu et al., 2023).
Serum T4 differed significantly (P<0.05) between pregnant and non-pregnant queens during 6th to 8th weeks, but not at 9
th week. Within pregnant queens, T4 remained stable during the 6
th to 7
th weeks but declined significantly in the 8
th to 9
th weeks. Similar late-gestational declines have been reported in dogs
(Hinderer et al., 2023), although contrasting findings were reported by
Cardinali et al., (2017). This decline may reflect haemodilution, increased hepatic metabolism and altered thyroid hormone-binding proteins (
Glinoer, 2004). Serum TSH remained below the assay detection limit (<0.25 ng/ml) in both groups, precluding statistical comparison. Similar undetectable levels have been reported in cats, indicating limited diagnostic utility (
Kabakçi and Elifoğlu, 2020). In contrast, pregnant dogs showed a mid-gestational decline followed by an increase near term, suggesting thyroid hormone mediated negative feedback and adequate maternal thyroid hormone availability for fetal development
(Hinderer et al., 2023).
