Manipulating Lipolysis to Reduce Fatness and Improve Carcass Composition in Commercial Broilers

Betaine has been studied as an osmolyte and methyl group donor for many species. Recent studies have found that betaine is able to increase muscle mass and reduce adiposity in meat type broilers birds. In experiment one, eight-hundred Cobb 500 broiler chicks were supplemented with betaine at 0.6 g/kg and 1.2g/kg. Birds had access to feed and water for ad libitum consumption for forty-two, forty-four, and forty-nine days. Birds and feed were weighed weekly. Carcass parameters (dress weight, breast percentage, and leg percentage) were taken at slaughter on days forty- two and forty-nine. Blood was taken at day forty-four to assess nonesterified fatty acids, triglycerides and glucose. Betaine did not have an effect on carcass performance, triglycerides or glucose. Betaine did however have a significant effect on NEFA concentration (p<0.05) indicating a betaine induced change in lipolysis.

In experiment two, ten one day old broilers were used to establish a protocol for lipolysis in broiler adipose explants. Adipose depots were harvested, cultured and treated with a variety of known lipolytic agents and nuclear receptor agonists. Media concentrations of glycerol and NEFA were measured to assess lipolytic activity of the explants. Treatments included: glucagon, isobutyl-1-methylxanthine(IBMX), isoproterenol, betaine, TO-901317, GW-7647 and rosiglitazone. Bezafibrate, IBMX, glucagon and TO-901317 had an significant effect on media glycerol and non-esterified fatty acid concentration (p<0.05) indicating an increase in lipolysis.