Study of the circulatory energy balance indicators and hepatic fat content in dromedary camel during late pregnancy and early lactation

Abstract

Lipid metabolism is a hallmark of energy metabolism in periparturient animals. Due to the lack of reports on fat metabolism during the transition period in camels, this study aimed to manifest the fluctuations in the fat metabolism indicators in serum and liver of camels during this period. Ten multiparous (with the parity of 2.38 ± 0.56; mean ± SEM) camels with a body weight of 527.94 ± 73.46 kg were studied 60 days antepartum (AP) until 60 days post-partum (PP). Blood was sampled at about (± three days) 60, 45, 30, 15, and three days before parturition, at parturition, and at the same time points during PP. Liver samples were collected through blind biopsy at about 15 days before calving, and at the same time points with blood collection during PP. No significant difference was observed for the concentration of TAG in the liver between days 15 AP until 3 PP. A definite increase was observed for liver TAG content at day 15 AP, which decreased gradually afterward (P < 0.05). Liver glycogen after an abrupt fall at parturition (P < 0.01), escalated during PP. Circulatory glucose decreased 15 days AP (P = 0.03) and did not return to the previous level until the end of the investigation. Right before parturition, serum TAG was distinctly low, but ascended 15 days PP (P < 0.05), and remained quite constant until the end of the study. Total lipid, phospholipids, HDL, and VLDL, were lowest at parturition (P < 0.05), then escalated temporally. As expected the correlation between serum concentrations of NEFA and β-hydroxybutyrate (BHB) during days 15 AP and 60 PP were highly positive (0.74; P < 0.01). Although hepatic TAG content was positively correlated with serum NEFA and BHB (P < 0.01), glycogen content of the liver revealed highly negative (P < 0.01) correlation with these two serum metabolites (both −0.75). This study, for the first time, denoted the preeminent fluctuations in lipid metabolism indicators during the physiological transition in pregnant camels. These results may be useful for comparative studies between camels and other species.