Nitrogen-15 Determination in Tissues of Laying Hens Fed on Different Levels of $^{15}N-Chlorocholine$ Chloride ($^{15}N-CCC$) Diets

다국어 초록 (Multilingual Abstract)

An experiment was conducted to determine the distribution of nitrogen-15 in tissues of laying hens receiving different levels of $^{15}N$-CCC in diets. Twenty brown laying hens were divided into four groups and randomly assigned into one of four dietary treatment groups consisting of 0, 5, 50 and 100 ppm $^{15}N$-CCC inclusion. The hens were individually fed with the $^{15}N$-CCC diets in battery cages for 11 days and then all hens restored to feeding on the control diet for 7 days. After eleven days, eight hens were slaughtered, and the others were slaughtered seven days after $^{15}N$-CCC diets withdrawal. Samples of blood, liver, heart and meat were collected and their $^{15}N$ contents were determined. The ${\delta}^{15}N$ excess (${\delta}^{15}N$-ex) and atom percentage excess in $^{15}N$ were calculated. The ${\delta}^{15}N$-ex and atom percentage excess $^{15}N$ increased significantly (p<0.05) with increasing levels of $^{15}N$-CCC in diets in all tissues after feeding $^{15}N$-CCC diets for eleven days. The highest concentration of ${\delta}^{15}N$-ex and atom percentage excess $^{15}N$ were detected in blood, followed in order by liver, heart and thigh meat. The concentrations reduced significantly (p<0.05) after $^{15}N$-CCC diets were withdrawn. Comparison between treatment groups showed that ${\delta}^{15}N$-ex and atom percentage excess $^{15}N$ were still higher in hens that had been fed diets with higher levels of $^{15}N$-CCC. This study showed that nitrogen-15 was distributed in blood, liver, heart and meat of laying hens.