Comparison of hematological parameters between single and twin pregnancies in Dorper ewes during gestation, lambing, and postpartum

Abstract

The hematopoietic system changes during the pregnancy to carry fetal development and maternal needs. This study compared the hematological parameters between ewes with single and twin pregnancies during gestation, delivery, and postpartum. The experiment was conducted on 60 healthy pregnant Dorper ewes that were divided into two experimental groups: Group 1 (G1), with single pregnancies (n=30), and Group 2 (G2), with twin pregnancies (n=30). Blood samples were collected from all ewes at different times: immediately before fixed-time artificial insemination (AI); on day 30, 90, 120, 130, and 140 of pregnancy; immediately after delivery; and at 24h and 48h postpartum. Statistical analysis compared the two groups at different times (P<0.05). Mild, normocytic, and hypochromic anemia was detected in all ewes from AI time and throughout pregnancy from both groups, but did not prove to be of clinical relevance. In the peripartum stage (from the 140th day of pregnancy to 48h postpartum), the ewes with twin pregnancies (G2) exhibited higher erythrogram values and neutrophil:lymphocyte ratio than did ewes with single pregnancies (G1). This indicated a greater hematopoietic adaptation in the body during the development of two fetuses. Except for the eosinophil numbers, all leukogram parameters were influenced by pregnancy in a similar way in both groups, and was characterized mainly by leukocytosis with neutrophilia during peripartum due to the high presence of endogenous cortisol at delivery. Thus, these findings showed that pregnancy was a stressful physiological event that increased the leukocyte count with a slight alteration in the erythrogram of Dorper ewes.

Endocrine-metabolic Adaptations in Dorper Ewes: Comparison Between Single and Twin Pregnancies During Gestation, Delivery, and Postpartum

“…The higher BW mean found in the G2 group compared to the G1 group from D0 can be justi ed by higher ovulation and proli cacy rates in the G2 group compared to the G1 group (Santarosa et al 2019a).…”

“…Adhikari et al (2018) found a suppression of glucagon secretion when animals were exposed to high energy diets. In the present experiment, the animals were maintained under the same nutritional diet; however, during pregnancy there was fatty acids mobilisation, with changes in cholesterol and triglycerides levels (Santarosa et al, 2019a), that can generate a negative feedback of glucagon secretion. Glucagon concentration showed large oscillations among sample time points and between groups analysed in the present study, although it did not represent a metabolic change due to pregnancy.…”

“…Decreased insulin sensitivity is observed at different life stages and is physiological at puberty, ageing, and pregnancy (Duehlmeier et al 2013;Brondani et al 2016;Sadegzadeh-Sadat et al 2021). A complex endocrine-metabolic adaptation occurs during pregnancy involving changes in insulin sensitivity, increased β cell mass response, slight elevation of blood glucose after feeding (Duehlmeier et al 2013), and changes in circulating levels of phospholipids, free fatty acids, triglycerides, and cholesterol (Santarosa et al 2019a). These changes are physiological because they represent a metabolic adaptation of the adequate energy supply to the foetus and preparation of the mother for delivery and lactation.…”

“…The ewes included in the present study belonged to the Araí & Zumbi sheep farm, located in Pardinho, São Paulo State, Brazil. A total of 150 non-pregnant healthy Dorper ewes between 2 and 5 years old were submitted to an estrous synchronisation protocol following the methodology described by Santarosa et al (2019a). Laparoscopic xed-time arti cial insemination (FTAI) was performed with frozen semen (D0) of the same breed.…”

“…Water and mineral salt (Ovinophos with Monensina®, Tortuga Agrarian Zootechnical Company, Mairinque, São Paulo, Brazil) were available ad libitum in automatic troughs. Mineral analysis of the total diet (feed, corn silage, and pasture) was undertaken following the methodology described by Santarosa et al (2019a), as well as the sanitary management. At the end of the experimental period, the ewes remained on the farm for lactation with their lambs.…”