Effect of dietary fat sources on fatty acid deposition and lipid metabolism in broiler chickens

Abstract

The hypothesis tested was that dietary vegetable fats rich in saturated fatty acids, when compared with a vegetable oil rich in linoleic acid, increase fat deposition in broiler chickens and affect synthesis or oxidation, or both, of individual fatty acids. Diets with native sunflower oil (SO), a 50:50 mix of hydrogenated and native SO, palm oil, and randomized palm oil were fed to broiler chickens. Intake of digestible fat and fatty acids, whole body fatty acid deposition, hepatic fatty acid profile, and hepatic enzyme activities involved in fatty acid oxidation and synthesis were measured. The fat deposition:digestible fat intake ratio was significantly lower for the SO group in comparison with the groups fed the vegetable fats rich in saturated fatty acids. The difference between digestible intake and deposition of C18:2, reflecting its maximum disappearance rate, was highest for the SO group and lowest for the palm oil- and randomized palm oil-fed birds. The calculated minimal rate of de novo synthesis of monounsaturated fatty acids (MUFA), calculated as deposition minus digestible intake, was more than 50% lower for the SO group than for the other 3 dietary groups. Based on the fatty acid profiles in the liver, it would appear that increasing contents of C18:2 decrease the desaturation of saturated fatty acids into MUFA. It is concluded that a diet rich in C18:2 in comparison with different kinds of vegetable saturated fatty acids decreases the deposition of fat, especially of MUFA. It appears to be caused by a higher β-oxidation and a reduced de novo synthesis of MUFA, but this conclusion is not fully supported by the measured activities of enzymes involved in fatty acid synthesis and oxidation.

Deposition of Dietary Bioactive Fatty Acids in Tissues of Broiler Chickens

“…Therefore, the slopes of the regression between tissue and dietary MCFAs and EFAs may represent the AR of these FAs in the tissues. Except that the AR of C18:2 is lower in the breast meat (i.e., 0.46), that of C18:2 and C18:3 in the thigh meat and abdominal fat (Table 3) is comparable with the values of 0.7 and 0.5, respectively (Villaverde et al, 2006;Smink et al, 2010). We found that the AR of MCFAs was less than 0.5 in the breast meat, thigh meat and abdominal fat.…”

“…The contents of EFAs and LCFAs shown in breast meat, thigh meat, and abdominal fat ( (Crespo and Esteve-Garcia, 2001;Smink et al, 2010). However, the contents of nonessential fatty acids (NEFAs) in the breast meat, thigh meat, and abdominal fat (Table 2) increased as the dietary MCTs increased (P＜0.05).…”

“…Therefore, the LCFA profile of the body clearly correlated with the dietary LCFA profile. The efficiency of deposition of EFAs was high in the body of broiler chickens (Villaverde et al, 2006;Smink et al, 2010).…”

Effect of Fat Extraction Methods on Fatty Acid and Infrared Profiles of Chicken Fat Using GC-MS and FTIR

“…In addition, Hilda [15] found 0.50 % of arachidonic acid in chicken fat and Guntarti et al [16] also explained that this was likely due to the arachidonic acid was lost by heating or derivatization during the extraction process. Smink et al [17] reported that chicken fat has high linoleic acid (omega-6 fatty acid) with percentages of 7.9-22.8 %. This can be seen that linoleic acid in GCMS results has percentage of about 15 % and it is one of dominant fatty acids in chicken fat.…”

Effects of Dietary Inclusion of Oil Sources With or Without Vitamin E on Body Composition and Meat Oxidation Level in Broilers*

“…Liver is where MUFA is synthesized. The presence of PUFAs in the diet leads to lower conversion of SFA into MUFA due to inhibitary effects of PUFAs on the activity of the enzyme Δ9-desaturase in the liver (Ajuyah et al, 1991;Lopez-Ferrer et al, 2001a,b;Villaverde et al, 2006;Smink et al, 2010). The high concentration of LA (18:2n-6) in the diet with only sunflower oil was reflected in its significantly greater incorporation into thigh and breast muscle compared with the 100% rapeseed oil dietary group (p=0.001).…”