Developmental Changes of Duckling Liver and Isolation of Primary Hepatocytes

Abstract

The liver is the main site of fat synthesis and plays an important role in the study of fat deposition in poultry. In this study, we investigated the developmental changes of duckling livers and isolated primary duck hepatocytes. Firstly, we observed morphological changes in duckling livers from the embryonic period to the first week after hatching. Liver weight increased with age. Hematoxylin-eosin and Oil Red O staining analyses showed that hepatic lipids increased gradually during the embryonic period and declined post-hatching. Liver samples were collected from 21-day-old duck embryos for hepatocyte isolation. The hepatocytes showed limited self-renewal and proliferative ability and were maintained in culture for up to 7 days. Typical parenchymal morphology, with a characteristic polygonal shape, appeared after two days of culture. Periodic acid-Schiff (PAS) staining analysis confirmed the characteristics of duck embryo hepatocytes. PCR analysis showed that these cells from duck embryos expressed the liver cell markers ALB and CD36. Immunohistochemical staining and immunofluorescence analysis also confirmed ALB and CK18 expression. Our findings provide a novel insight regarding in vitro cell culture and the characteristics of hepatocytes from avian species, which could enable further studies concerning specific research on duck lipid metabolism.

Embryonic growth and effect of embryonic age on quantitative and functional characteristics of duck primary hepatocytes

“…To gain a better understanding of the growth characteristics of the isolated cells, a cell growth curve was measured at E14. Cell counts were recorded every 24 h, showing a trend of initial increase, followed by a decrease, then another increase, and finally reaching a relatively stable cell quantity, which was similar to Bao's findings ( Bao et al, 2023 ). Normally, cell quantity would increase initially and then decrease until aging ( Zhao et al, 2022 ).…”

“…This situation could be attributed to the fact that as EA increased, the liver not only grew in size and weight ( Chen and Rui, 1992 ; Zhu et al, 2012 ), but also in the number of cells. However, during the middle and late stages of the embryonic period, particularly after reaching its peak at E16, the sharp decrease may be mainly due to the increasing lipid droplet content in hepatocytes ( Chen and Rui, 1992 ; Na et al, 2012 ; Bao et al, 2023 ). After centrifugation, hepatocytes with high-fat content are prone to rupture ( Liu et al, 2018 ) and are suspended in the centrifuged supernatant due to their low density, resulting in a significant decrease in the sediment.…”