• Korean Journal of Poultry Science
• /
• v.22 no.1
• /
• pp.1-6
• /
• 1995

A total of 514 birds were used to investigate the influence of body weight and shank length at hatch on the body weights at various ages in growing pheasant. Statistical model included the terms of hatch and sex as fixed effects and the two covariates of body weight and shank length at hatch. In this model, the effects of hatch and sex on the body weights at the age of 4, 8, 12, 16 and 20 wk, and the average daily gains from hatch to 8 wk and from 8 to 16 wk of age were highly significant(P<0.01). All the regression coefficients of body weights and average daily gains on the body weight at hatch were also significant(P<0.01). Their estimates were 3.05.7.21. 13.89, 15.18 and 15.33 for the body weights at 4. 8, 12, 16 and 20 wk of age ; 0.111 and 0.142 for the average daily gains from hatch to 8 wk, and from 8 to 16 wk of age, respectively. On the shank length, only the regression coefficients of the body weights at 4 and 8 wk of age and the average daily gains from hatch to 8 wk of age were significant(P<0.01). Results of this study suggest that body weight at hatch do significantly affect the body weights in the growing periods up to' the 20 wk of age, but the shank length at hatch influences the body weights only at early age.1)

• Korean Journal of Poultry Science
• /
• v.20 no.4
• /
• pp.197-201
• /
• 1993

The objective of this study was to investigate the effects of hatch and sex on the body weight and shank length of growing pheasant. Least squares means of body weight at the age of 0, 4, 8, 12, 16 and 20 wks were 17.9, 96.0, 296.4, 563.4, 709.0 and 757.4 g for female, and 18.3, 104.4, 349.1, 728.5, 1001.4 and 1101.6 g for male, respectively. The hatch effect on body weight was significant at the age of 4, 8, 12 and 16 wks (P＜0.05), but the effects on shank length were significant at the age of birth and 8 wks only. There was no significant hatch effect on both the body weight and shank length at the age of 20 wks(P＞0.05). Least squares mean differences between female and male were significant(P＜0.01) over all wks of age except at hatch.

• Korean Journal of Poultry Science
• /
• v.20 no.4
• /
• pp.203-208
• /
• 1993

The objective of this study was to investigate the correlation among the measurements of the body weight and shank length at the age of 0, 4, 8, 12, 16 and 20 wk, and to investigate the regression of the final body weight at the age of 20 wk in selection on the body weight and shank length before 12 wk of age. From the simple correlation analysis, the range of correlation coefficients between body weight and shank length at the same age were 0.50~0.83 from females, and 0.57~0.85 from males over all wk of age(P＜0.01). Correlation coefficient between the body weights at hatch and 20 wk of age was 0.44(P＜0.01), but it was not significant(P＞0.05) between the shank length at hatch and body weight at 20 wk of age. The favorable regression models for the estimation of the body weight at the age of 20 wk from both body weight and shank length before 12 wk of age were the models with the independent variables of measurements at hatch and 12 wk of age($R^2$＝0.96), with the measurements at 8 and 12 wk of age($R^2$＝0.96), and with the measurements at 0, 8 and 12 wk of age ($R^2$＝0.96).

• Korean Journal of Agricultural Science
• /
• v.47 no.2
• /
• pp.255-262
• /
• 2020

The aim of this study was to investigate the growth performance between two different crossbred strains of Korean native chickens denoted as 1E and 2E with a white semibroiler (LL) from hatch to d-84 post-hatch. A total of 450 one-day-old chicks were randomly distributed into cages which included 15 replicate cages each for 1E and 2E with 9 replicate cages for LL. A three phase feeding program was used as a starter (Day 1 - 35; crude protein [CP] 20.3%; metabolizable energy [ME] 3,059 kcal·kg^-1), grower (Day 36 - 56; CP 18.6%; ME 3,123 kcal·kg^-1) and finisher (Day 57 - 84; CP 16.7%; ME 3,187 kcal·kg^-1). The results revealed that LL had a higher (p < 0.05) BW during d-8 to d-84 compared with the other two cross breed groups. A higher (p < 0.05) ADG was observed from the LL during the entire period except from d-1 to d-14 and d-71 to d-84 when compared with 1E and 2E. Shank length did not vary (p > 0.05) between the strains, despite LL having a SL that was 2.86% higher (p < 0.05) when compared with the other strains from d-15 to d-21 post-hatch, and 1E had a SL that was 2.28% (p < 0.05) higher when compared with the other strains during the first week of the experiment.

• Korean Journal of Agricultural Science
• /
• v.47 no.3
• /
• pp.605-614
• /
• 2020

This study was conducted to compare the growth performances of three groups of commercial Korean native chickens (KNCs) including two strains of crossbreeds and H3 (Hanhyeop 3) from hatch to twelve weeks of age. (1A, 2A, and H3). A total of 468 one-day-old chicks were allocated in a completely randomized design with 15 replicates per treatment for the crossbreeds and 9 replicates per treatment for H3 (12 birds per cage). Commercial broiler diets (i.e., Week 0 - 5 crude protein [CP] 22.0%, metabolizable energy [ME] 3,025 kcal·kg^-1; week 5 - 8 CP 20.0%, ME 3,100 kcal·kg^-1; week 8 - 12 CP 19.0%, ME 3,150 kcal·kg^-1) were provided according to the Korean Feeding Standard for Poultry on an ad-libitum basis with fresh clean water during the twelve-week period. Body weight gain and shank length (SL) were measured weekly until week 6 and bi-weekly during week 6 to 12. Compared to H3, the two crossbreed groups had a higher body weight (BW) on weeks 3 to 8; however, the bodyweight of H3 on week 10 was significantly higher than the other groups (p < 0.05). Moreover, the average daily feed intake (ADFI) of H3 was higher than that of the two crossbreed groups from hatching to 84 days except for week 3, and H3 showed a lower average daily gain (ADG) on weeks 3 and 10 (p < 0.05). Furthermore, H3 had a higher feed conversion ratio compared to another crossbreed chicken on weeks 1 to 8 and the last week after hatching. Among all the groups, there was no significant difference for shank length during the experimental period.

• Korean Journal of Agricultural Science
• /
• v.48 no.1
• /
• pp.171-178
• /
• 2021

A comparative study was conducted to examine the effects of mixed and separate gender feeding on growth performance of Korean native chickens (KNC) against a white semi-broiler (WSB) and a commercial broiler (CB) over five weeks. 576 chicks were used with eight birds per cage in a randomized complete block design with 18 replicates per breed. For the KNC lines, three groups of male (M), female (F) and mixed-gender (FM) were used. Fresh water and feed were supplied on an ad-libitum basis. Birds were fed a standard starter (d 1 - 22) and grower diet (d 23 - 35). Body weight (BW), feed intake, and shank length (SL) were measured weekly. From the BW and feed consumed data, the average daily feed intake (ADFI), average daily gain (ADG), and feed conversion ratio (FCR) were calculated. The commercial broiler showed higher performance (p < 0.05) for all the indices measured for the entire period. The CB group consumed more feed and were more feed-efficient thus grew faster. This group was followed by the white semi-broiler and the KNC, in order. An intra-breed comparison for KNCs revealed that the males showed better growth performance with longer SL (p < 0.05) compared to the female and mixed-gender groups. The results showed that other than the breed type, mixed and separate gender feeding impacted on the growth performance of the two lines of Korean native chickens. Males for both lines of KNC generally performed better for the parameters measured, as determined by a greater BW and reduced FCR.