Page Banner

United States Department of Agriculture

Agricultural Research Service

Research Project: SAFEGUARDING WELL-BEING OF FOOD PRODUCING ANIMALS Title: Changes of blood parameters associated with bone remodeling following experimentally induced fatty liver disorder in laying hens

Authors
item Jiang, S -
item Cheng, Heng Wei
item Cui, L -
item Zhou, Z -
item Hou, J -

Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 10, 2013
Publication Date: June 1, 2013
Repository URL: http://handle.nal.usda.gov/10113/56771
Citation: Jiang, S., Cheng, H., Cui, L.Y., Zhou, Z.L., Hou, J.F. 2013. Changes of blood parameters associated with bone remodeling following experimentally induced fatty liver disorder in laying hens. Poultry Science. 92:1443-1453.

Interpretive Summary: Osteoporosis, a progressive decrease in mineralized structural bone that causes 20 to 35% of all mortalities in caged White Leghorn hens. Studies have demonstrated that obesity and osteoporosis are two linked disorders. This study examined if excessive energy consumption affects bone metabolism in laying hens. One hundred 63-week-old laying hens were randomly divided into two treatments, i.e., fed with a regular diet (control treatment) or a high energy and low protein diet (HE-LP; experimental treatment) for 80 days. The results indicated that HE-LP diet successfully induces a fatty liver disorder in laying hens with an up-regulated bone turnover, exacerbating skeletal damage. Data suggests that there is an interaction between fat metabolism and skeletal health in chickens. These data can be used by egg producers to develop guidelines for improving chicken welfare by modification of diets.

Technical Abstract: Studies have demonstrated that obesity and osteoporosis are two linked disorders in humans. This study examined if excessive lipid consumption affects bone metabolism in laying hens. One hundred 63-week-old laying hens were randomly divided into two treatments, i.e., fed with a regular diet (control treatment) or a high energy and low protein diet (HE-LP; experimental treatment) for 80 days. Egg production, feed intake, and BW were recorded at various days during the treatment. At day 80, 10 birds per group were randomly sacrificed. Abdominal fat weight, liver weight, and liver fat content were measured. Serum total calcium, inorganic phosphate, and alkaline phosphatase were detected using a biochemical analyzer. Serum levels of osteocalcin, leptin-like protein, and estrogen were detected by enzyme-linked immunosorbent assay. Tibia length and width were measured using a vernier caliper; density of the right tibias was detected using an X-ray scanner; and mechanical properties of the left tibias were analyzed using a material testing machine. The expression of osteocalcin and osteoprotegerin mRNA in the keel bones were analyzed by Real-time PCR. The levels of osteocalcin protein in the keels were also analyzed by Western blot. Compared with control hens, hens fed with HE-LP diet had a lower egg production, lower feed intake, heavier liver fat content and abdominal fat pad (P < 0.05). HE-LP diet also caused increases in serum alkaline phosphates activity, the serum concentrations of osteocalcin, leptin-like protein and estrogen (P < 0.05), and decreases in keel osteocalcin concentrations (P < 0.05). There were significant positive correlations between the serum concentrations of leptin-like protein, estrogen, and osteocalcin regardless of treatment (P < 0.05). The results indicate that HE-LP diet successfully induces a fatty liver disorder in laying hens with an up-regulated bone turnover, exacerbating skeletal damage. Data suggests that there is an interaction between fat metabolism and skeletal health in chickens.

Last Modified: 10/25/2014