• Korean Journal of Poultry Science
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• v.51 no.3
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• pp.153-159
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• 2024

This study investigated the growth performance and fat deposition in Woorimatdag2 (WMD2) breeder pullets in response to dietary levels of apparent metabolizable energy (AMEn). A total of 144 four-week-old WMD2 breeder pullets were weighed and equally divided into four dietary groups, each with four replications until 16 weeks of age. The dietary groups were fed diets formulated with AMEn levels; 2,600, 2,700, 2,800, and 2,900 kcal/kg. The results showed that birds fed 2,800 and 2,900 kcal/kg were higher (P<0.05) in body weight and weight gain compared to those fed 2,600 kcal/kg. Feed conversion ratio was significantly (P<0.05) improved in 2,900 kcal/kg-fed group compared to 2,600 and 2,700 kcal/kg-fed groups. The laying ages of first egg were earlier (P<0.05) in 2,600 and 2,700 kcal/kg-fed pullets than 2,900 kcal/kg-fed those. Meanwhile, the higher (P<0.05) fat (%) into both liver and abdomen was confirmed in groups fed 2,700, 2,800, and 2,900 kcal/kg compared to group fed 2,600 kcal/kg. Furthermore, blood concentrations of AST and ALT were significantly (P<0.05) increased in group fed 2,900 kcal/kg compared to groups fed 2,600, 2,700, and 2,800 kcal/kg. Accordingly, we suggest that 2,600 kcal AMEn/kg is appropriate for WMD2 breeders during growing phase, which may improve their productivity and health of those during laying phase.

• Korean Journal of Poultry Science
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• v.40 no.2
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• pp.121-127
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• 2013

This work was carried to evaluate production efficiency factor, carcass yield and meat quality with weeks of Large-type Korean native ducks. Korean native ducks (n = 90) from National Institute of Animal Science (RDA, Korea) were used in this work. Ninety ducks were divided into 6 groups (15 birds/group) and were fed with meat-type duck diets for 8 wk old. When ducks grew at specific wk (6, 7 and 8 weeks), 2 ducks per group were slaughtered at 6, 7 and 8 wk old. Production efficiency factor, carcass yield, partial meat and meat quality were researched in this work. There was no significant difference on livability with weeks, but body weight at 7 and 8 wk old was higher than that at 6 wk old (P<0.05). Feed conversion ratio at 6, 7 and 8 wk old were 2.25, 2.69 and 3.21, respectively, so there was significant difference with weeks (P<0.05). Production efficiency factor at 6, 7 and 8 wk old were 256.6, 199.8 and 153.0, respectively, so there was significant difference with weeks (P<0.05). Carcass yield at 8 wk old was higher than that at 6 and 7 wk old as 73.5% (P<0.05). Lightness at 6, 7 and 8 wk were 41.8, 39.0 and 38.1, respectively, and that at 6 wk old was the higher than other weeks (P<0.05). There was no significant difference on redness at 6, 7, and 8 wk old (P>0.05) and yellowness at 8 wk old was higher compared to other weeks (P<0.05). Cooking loss was the highest at 6 wk old as 31.6%, but water holding capacity was the highest at 8 wk old (P<0.05). There was no significant difference on shear force among weeks. pH at 6 wk old was the lower than that of other weeks as 5.84. Moisture content significantly decreased with weeks (P<0.05) and fat content at 8 wk was the highest as 1.88% (P<0.05). Protein content significantly increased with weeks until 20.9% at the age of 8 wk (P<0.05). Ash content at 7 and 8 wk old was the higher than that at 6 wk old (P<0.05). There was no significant difference on juiciness, tenderness, and flavor with weeks. Finally, these results may provide that shipping time at 7 wk old preferred to that at 6 and 7 wk old, but further research was needed because of deficiency of data.