Effects of Cod Liver Oil and Chromium Picolinate Supplements on the Serum Traits, Egg Yolk Fatty Acids and Cholesterol Content in Laying Hens

Tu-Fa Lien,Jin-Jenn Lu,Chaen-Ping Wu

doi:10.5713/ajas.2003.1177

Abstract

This study investigated the effects of cod liver oil and chromium picolinate on the serum traits and egg yolk fatty acids and cholesterol content in laying hens. One hundred 45-week old single comb white Leghorn laying hens were assigned randomly to four groups. These groups were: (1) control (soybean oil), (2) 1,000 ppb (µg/kg) chromium (organic form chromium picolinate) (Crpic), (3) 3% cod liver oil (CLO), and (4) 1,000 ppb chromium with 3% cod liver oil (CLO+Crpic). The experiment was conducted for 40 days. Results indicated that serum triacylglycerol (TG) and cholesterol contents in the CLO group and the serum glucose content in the Crpic group were significantly lower than those in the control group (p<0.05-0.01). The yolk cholesterol content in the CLO and Crpic groups were also lower than the control group (p<0.01). The lipoprotein profile displayed that in the Crpic group, high-density lipoprotein (HDL) and HDL-cholesterol (HDL-C) were significantly higher (P<0.05) than the control group. Meanwhile, low-density lipoprotein+very low-density lipoprotein (LDL+VLDL) and LDL-C+VLDL-C were significantly lower (p<0.05) than the control group. Notably, of all four groups, the CLO group displayed a more profound effect on serum traits and lipoprotein (p<0.05-0.001). Furthermore, the fatty acid composition of the egg yolks presented that C18:2 in the CLO and Crpic groups was significantly lower (p<0.05-0.001) compare to the control. However, only in the CLO group, C18:3, C20:5 and C22:6 were significantly higher (p<0.001) than the control. Only serum glucose and LDL+VLDL showed the CLO×Crpic interaction (p<0.05), most parameters did not. Therefore, supplemented chromium picolinate or cod liver oil in the diet of laying hens had beneficial effects. However, when these two factors were combined, there was no interaction with most parameters. (Asian-Aust. J. Anim. Sci. 2003. Vol 16, No. 8 : 1177-1181)

Highlights

Several studies have reported that feeding laying hens with a ration rich in ω-3 polyunsaturated fatty acids (PUFA)
Our previous study indicated that a diet supplemented with chromium picolinate could markedly reduce the cholesterol contents in serum LDL and that in the egg yolk of laying hens (Lien et al, 1997)
Cod liver oil and chromium picolinate were added to a laying hen diet to further investigate their effects on serum traits and yolk cholesterol

Summary

INTRODUCTION

Several studies have reported that feeding laying hens with a ration rich in ω-3 polyunsaturated fatty acids (PUFA). Evans (1989) and Page et al (1993) indicated that an organic form of trivalent chromium supplement could reduce blood cholesterol levels. Our previous study indicated that a diet supplemented with chromium picolinate could markedly reduce the cholesterol contents in serum LDL and that in the egg yolk of laying hens (Lien et al, 1997). Received January 25, 2003; Accepted April 14, 2003 domestic animals (Lien et al, 1996, 1997, 1998, 1999, 2001) It is involved in carbohydrate, lipid, amino acid and nucleic acid metabolism (Okada et al, 1984; Press et al., 1990; McCarty, 1991; Xi et al, 2001) and is considered as an essential animal trace element. Cod liver oil (enrich with ω-3 PUFA) and chromium picolinate were added to a laying hen diet to further investigate their effects on serum traits and yolk cholesterol

MATERIALS AND METHODS

RESULTS

DISCUSSION

CONCLUSION