Effects of restricted feeding on fetal and placental development in pregnant rabbits

Abstract

-In our previous study on the effects of restricted feeding on pregnant rabbits (Matsuoka et al., 2009), animals given 20 g/day of diet on and after gestation day 6 (GD 6) showed significant changes in blood coagulation-related parameters suggesting a tendency to bleed and a decrease in serum concentration of progesterone, an important factor to maintain pregnancy, on GD 22, and a half of them showed serum progesterone concentrations less than 4.0 ng/ml which resulted in abortions on and after GD 23. In the present study, the effects of restricted feeding of 20 g/day from GD 6 to GD 22 on embryo-fetal and placental development on GD 23 as well as on blood coagulation-related parameters and serum progesterone concentrations on GD 22 were examined in pregnant rabbits. As compared with the non-restricted feeding (Not-treated, NT) group, the restricted feeding (RF) group showed lower values of platelets, fibrinogen, activated partial thromboplastin time (APTT) and antithrombin III (ATIII) and a longer prothrombin time (PT), reflecting an inhibition of blood coagulation, and a decrease in serum progesterone concentration on GD 22. Cesarean section performed on GD 23 revealed that the RF group showed a tendency towards an increase in the embryo-fetal death index and lower body weights and placental volumes compared with the NT group. Histological examination of the placenta in the RF group revealed that the labyrinth zone was thin and many glycogen-containing cells still remained in the basal zone, suggesting a delay in placental growth.

Competition for Materno-Fetal Resource Partitioning in a Rabbit Model of Undernourished Pregnancy

“…Interestingly, the microscopic assessment of placental thickness showed a significant reduction in labyrinth expansion in both undernourished groups, which supports previous work [35]. The progressive reduction in the surface area of the labyrinth may affect placental nutrient transporters and contribute to the poor fetal outcome.…”

“…Moreover, hemodynamic changes occurring during pregnancy are also similar to the human, with an important increase in maternal blood pressure throughout gestation [32, 34]. In rabbits, the effects of MFR during gestation [17, 30, 31, 35–41] vary depending on the period of the pregnancy exposed, the level of the restriction applied and the capacity of the mother to compensate, particularly during late pregnancy when fetal growth is maximal [42]. When it comes to the mother, MFR is usually linked to metabolic and hormonal changes [35–37] and low milk production [38].…”

“…In rabbits, the effects of MFR during gestation [17, 30, 31, 35–41] vary depending on the period of the pregnancy exposed, the level of the restriction applied and the capacity of the mother to compensate, particularly during late pregnancy when fetal growth is maximal [42]. When it comes to the mother, MFR is usually linked to metabolic and hormonal changes [35–37] and low milk production [38]. Meanwhile, in the fetus, hemodynamic alterations and poor biometric outcomes can be observed [17, 30, 31, 39–41].…”

Food restriction during pregnancy in rabbits: Effects on hormones and metabolites involved in energy homeostasis and metabolic programming

“…Previous studies on rabbits have evaluated the effects of restricted feeding during pregnancy on productive performance (Manal et al, 2010;Rommers et al, 2004a), as well as on embryo-foetal and placental development (Cappon et al, 2005;Matsuoka et al, 2012), but little is known on hormones and metabolites involved in energy homeostasis.…”

Food restriction during pregnancy: effects on body condition and productive performance of primiparous rabbit does

“…intake, productive performance (Rommers et al, 2004b;Manal et al, 2010;Nafeaa et al, 2011), organogenesis (Cappon et al, 2005), placental development (Matsuoka et al, 2012) and some blood parameters (Matsuoka et al, 2009). However, evaluation of body condition is needful not only because it is correlated to short-and long-term reproductive efficiency, but also to animal health and welfare (Castellini et al, 2010;Sánchez et al, 2012;Pascual et al, 2013).…”