Effect of Selenium Source and Level in Hen's Diet on Tissue Selenium Deposition and Egg Selenium Concentrations

Abstract

The present study was conducted in a 2 x 4 factorial arrangement in a randomized complete block (RCB) design to compare the effects of a commercial inorganic Se source (sodium selenite, SS) with a commercial organic Se source (Se-enriched yeast, SY) on tissue Se distribution and blood and whole-egg Se concentrations in laying hens. Both Se sources were added into the basal diet at 0, 0.2, 0.5, and 1.0 mg/kg of Se. Seven hundred 68 week old Rohman laying hens were fed with a basal diet containing 0.15 mg/kg DM (dry matter) of Se for 2 weeks, and then, they were allocated randomly into seven groups and were investigated for 28 days. Each group was replicated five times with five cages of four hens per cage in each replicate. During the experiment, two eggs per replicate from each treatment were collected every 7 days and blood was sampled on days 0, 14, and 28 for whole-egg and whole-blood Se analyses. At the end of the experiment, two hens per replicate from each treatment were slaughtered, and muscle (cardiac and breast muscles), liver, spleen, and kidney were sampled for the determination of Se concentrations. The results showed that the addition of Se from either source caused a significant increase in whole-egg and whole-blood Se concentrations (p < 0.01) and Se concentrations in liver, kidney, spleen, and cardiac and breast muscles (p < 0.05) of hens in comparison to the control. Both Se sources and Se levels significantly influenced (p < 0.01) Se concentrations in egg, blood, and the above-mentioned tissues. There was a more significant increase in the Se concentrations in egg (p < 0.01), spleen (p < 0.05), and breast muscle (p < 0.01) and a decrease (p < 0.01) in whole-blood and kidney from hens fed SY than those from hens fed SS. The order of Se distribution was liver > kidney > spleen > cardiac muscle > egg > blood > breast muscle, irrespective of the addition level or source. It was concluded that meat and eggs from hens fed commercial SY are a potential source of Se for humans.

Effect of dietary supplementation with selenium-enriched yeast or sodium selenite on selenium tissue distribution and meat quality in commercial-line turkeys

“…Selenium content of blood and plasma The lack of any significant response in blood and plasma Se concentrations of unsupplemented birds would be expected and is consistent with the findings of other authors investigating the effects of supplementary Se on poultry (Echevarria et al, 1988;Pan et al, 2007;Yoon et al, 2007). The differences seen between comparable doses of the different Se supplements from the current study are indicative of better uptake and incorporation of Se derived from SY and are consistent with findings in sheep (Van Ryssen et al, 1989;Juniper et al, 2008a), cattle (Gunter et al, 2003;Juniper et al, 2008b;Phipps et al, 2008) and pigs (Kim and Mahan, 2001).…”

“…Glandular visceral tissues tend to have greater total Se concentrations than muscle, and cardiac muscle has a greater total Se content than skeletal muscle. These data agree with those reported in laying hens (Petrovič et al, 2006;Pan et al, 2007) and broilers (Wang and Xu, 2008) and are also similar to those reported in lambs (Juniper et al, 2008a) and beef cattle (Juniper et al, 2008b). The differences seen in cardiac, skeletal and gizzard muscle tissue total Se concentrations, when comparing comparable doses of the two sources of Se, are indicative of improved Se uptake and incorporation within those birds supplemented with SY.…”

“…Petrovič et al (2006) reported that total Se concentrations were greater in the kidney, liver and pancreatic tissues of SY-supplemented laying hens when compared with those receiving a comparable dose of SS, but there were no differences between Se sources in muscle tissue. Pan et al (2007) reported that tissue total Se concentrations were similar in liver tissue of laying fowl when comparing sources but greater in the muscle tissue of SY-supplemented birds when compared with SS. Similar effects of Se source have been reported within the cardiac and skeletal muscles of cattle, sheep (Juniper et al, 2008a and and loin tissue of pigs (Mahan et al, 1999;Mateo et al, 2007), whereby tissue total Se concentrations have been greater in SY-supplemented animals when compared with those receiving a comparable dose of SS.…”

“…Yoon et al (2007) reported that there were differences between Se sources in 6-week-old broilers that had received diets containing comparable doses of SS and SY; but differences also existed between comparable doses of different organic sources. Pan et al (2007) showed that Se responses in the blood of 6-week-old broilers were greater in birds fed SS when compared with birds fed a comparable dose of SY. Pan et al (2007) postulated that the differences seen between domestic fowl and cattle or pigs could be attributable to animal class differences (avian v. mammalian).…”

“…Pan et al (2007) showed that Se responses in the blood of 6-week-old broilers were greater in birds fed SS when compared with birds fed a comparable dose of SY. Pan et al (2007) postulated that the differences seen between domestic fowl and cattle or pigs could be attributable to animal class differences (avian v. mammalian). However, the results of the current study indicate that this may not be entirely the case.…”