Trend analysis of plasma insulin level around parturition in relation to parity in Saanen goats1

Abstract

The present study investigated the effect of parity on plasma insulin level around parturition in Saanen goats. 0, 3, 7, 10, and 14 from parturition, plasma glucose, NEFA, free AA, cortisol, and insulin concentrations were analyzed in 10 primiparous and 10 multiparous goats. At parturition, BW of primiparous goats was about 75% of that of multiparous ones (P < 0.001) and then their milk production was lower than that of multiparous ones (P < 0.001). At parturition, glucose increased (P < 0.01) in both primiparous and multiparous goats and then decreased (P < 0.01) on d 3 of lactation, remaining higher (P < 0.01) in primiparous than multiparous goats until the end of the study period. In both groups, free AA decreased (P < 0.01) at parturition, returning to prepartum levels (P < 0.01) on d 3 of lactation without difference between groups. Only in multiparous goats, plasma NEFA increased at parturition (P < 0.01), returning to prepartum levels on d 14 (P < 0.01). Changes in glucose and AA could have been caused by cortisol, which increased (P < 0.01) at parturition in both primiparous and multiparous goats, returning to prepartum levels (P < 0.01) on d 7 of lactation, without difference between the parity groups. In multiparous goats, insulin decreased soon after parturition (P < 0.05), remaining at low levels until the end of the study period, whereas in primiparous goats, insulin did not vary until d 14 of lactation, when it decreased (P < 0.05) also in this group. Therefore, between d 3 and 14 of lactation, insulin was higher in primiparous than multiparous goats (P < 0.05). Only in primiparous goats, at kidding, insulin was negatively correlated to BW (P < 0.01), and after parturition it was negatively correlated with milk yield (P < 0.05) and plasma NEFA (P < 0.05). We hypothesize that higher insulin levels in primiparous Saanen goats, which are still immature at their first breeding season, acted to limit both the mobilization of bodily reserves and the capture of nutrients by the lactating mammary gland, thus providing nutrients for their own physical and physiological development.

Changes in plasma biochemical parameters and hormones during transition period in Beetal goats carrying single and twin fetus

“…An increase in glucose concentration at parturition may be due to the high concentration of glucocorticoid hormones such as cortisol, which promotes an increase in hepatic glycogenolysis and gluconeogenesis from glucose precursors as it is major energy substrate for the developing fetus, uterus, and placenta [ 9 , 10 ]. In the last trimester of gestation, glucose level was higher in goats carrying twins due to higher demand by fetus, as it was found a positive correlation between fetal abdominal circumference and maternal blood glucose levels [ 11 ].…”

Impact of short nutrient stimuli with different energy source on follicle dynamics and quality of oocyte from hormonally stimulated goats

“…Under these conditions, goats mobilize fatty acids from fat tissue reserves to compensate for the lack of glucose and fatty acids (Invernizzi et al, ). This mechanism leads to an increase in circulating concentrations of non‐esterified fatty acids (NEFA) during the end of gestation and the post‐partum period (Magistrelli & Rosi, ). Recent researches have shown that the use of fat reserves in goats is influenced by energy diets, with limitations in lipolysis (Invernizzi et al, ) and increase in sternal subcutaneous fat thickness (Fernandes et al, ), with maximum values of 11.4, which are similar to that found in the present study (10.5).…”

Effects of pregnancy and post-kidding stages on haematochemical parameters in cross-bred goats

“…Pregnant goats were bled weekly from day -49 (n = 7 sampling dates) prior to kidding to day +21 (n = 3 sampling dates) postkidding (day of kidding = 0). During this period, it was supposed that goat physiology adjusts in order to fulfil the foetuses' demand for nutrients and, later, to reach the lactation peak production (Celi et al 2008;Magistrelli & Rosi 2014;Radin et al 2015). Control goats were sampled the same as pregnant/ post-kidding goats.…”