Live production and carcass characteristics of broilers fed a blend of poultry fat and corn oil derived from distillers dried grains with solubles.

Corn distillers dried grains with solubles (DDGS) are now being further processed to remove corn oil, which may be used as a dietary energy source for poultry. The objectives of this study were to compare the effects of a poultry fat (PF) and a new DDGS-derived corn oil blend (CO) on live performance and carcass characteristics of 49-d-old broilers. Four corn-soybean meal based diets were formulated with differing blends of PF and CO. All diets contained the same percentage of total fat, but differed in the fat source. One diet had the sole source of fat as PF (100:0% PF:CO) and was then replaced with 25% CO, 75% CO, and a 100% replacement of CO. Each of the diets was fed in a 3-phase feeding program to 6 replicate pens. At day of hatch, Ross × Ross 708 broilers were randomly allocated to 24 pens composed of 42 birds of equal sex. On d 49, 10 birds from each pen were processed, and carcass, abdominal fat pad, and breast muscle components were determined. There were no significant differences in live performance for the starter phase (0-18 d). For the grower phase (19-35 d), birds fed 75:25% PF:CO significantly (P ≤ 0.05) increased BW, BW gain, and decreased feed conversion compared with the control (100:0% PF:CO). Birds fed 0:100% PF:CO also observed similar improvements in BW, BW gain, and feed conversion during the grower phase. There were no significant differences for the finisher phase (36-48 d). On d 49, live weights for birds fed the 0:100% PF:CO diets were significantly lower compared with other treatments. A trend for lower carcass and breast weights and increased abdominal fat was also observed for birds fed the 0:100% PF:CO. The addition of CO led to significant improvements in pellet durability for grower and finisher pellets. The results of this study indicate that DDGS-derived CO can be used to partially replace PF in broiler diets without any detrimental effects.

Interaction between orosensory and postingestional stimulation in the control of corn oil intake by rats.

The microstructure of the ingestive behavior of rats ingesting corn oil emulsions was analyzed to describe quantitatively how postingestional stimulation interacts with orosensory stimulation to control the intake of corn oil. Seventeen hour food deprived rats were given 30-min access intake tests with corn oil emulsions ranging in concentration from 0.125% to 64%. The volume ingested showed an inverted U shaped function over this concentration range. The Weibull function fitted to the rate of licking function showed that the initial rate of licking was an increasing linear function of the log of the concentration of corn oil. The slope of the licking rate function was an increasing curvilinear function of the log of corn oil concentration. Together these results indicate that the negative feedback effect of corn oil in the gastrointestinal tract increases more rapidly at the higher concentrations of corn oil than does its orosensory stimulating effect resulting in a decrease in the volume ingested. Unlike carbohydrates, where the increase in the initial rate of licking is a result of an increase in the size of the clusters, the increase with concentration in the initial rate of ingesting corn oil was caused by an increase in the number of clusters rather than their size. This study provides a quantitative analysis of the interaction between orosensory and postingestional stimulation, two variables that play an important role in the control of ingestion of corn oil.

Sustained intracerebroventricular infusion of brain fuels reduces body weight and food intake in rats.

Long-term infusion of glucose, beta-hydroxybutyrate, and glycerol into the third ventricle of the rat brain caused a stabilization of body weight at a lower than normal level. Among the glucose- and glycerol-treated animals this weight loss was caused in part by temporary hypophagia. Among the animals treated with beta-hydroxybutyrate the weight loss was unaccompanied by a reduction in food intake. The results are consistent with the view that the systems controlling food intake and body weight are sensitive to the availability of brain fuels. They are not consistent however, with the view that these control systems monitor calories independently of their source.