• Korean Journal of Poultry Science
• /
• v.29 no.2
• /
• pp.135-140
• /
• 2002

An experiment was conducted to determine the effects of vitamin C supplementation on the performance and egg quality of layers. A total of 800 ISA Brown layers of 71 weeks old were assigned to one of the following diets containing 0, 3, 10, 50 or 100 ppm LG-vitamin C, 100ppm free ascorbic acid, 100 ppm Rovimix stay C-35 or 50 ppm LG-vitamin C supplemented with 100 ppm Zn methionine chelate. The feeding trial was conducted for flour weeks during the period of May to June when the average ambient temperature was $23.8^{\circ}C$ (5 :00 PM). Each treatment was replicated five times with 20 birds housed in 2 birds cage units. Vitamin C supplementation did not improve the overall performances (egg Production and egg Quality). Birds fed 100 ppm of LG vitamin C had the lowest egg Production while birds fed 100 ppm of Rovimix-35 had the lowest egg weight among birds fed different sources of vitamin C. Although supplementation of vitamin C over 50 ppm increased soft and broken egg Production, supplementation of 10 ppm LG vitamin C showed lowest soft and broken egg Production among all treatments. E99she11 thickness was highest in the treatment of 50 ppm LG vitamin C. In conclusion, supplementation of vitamin C at the level of 3 ~ 100 ppm did not significantly influence the laying performance and eggshell quality of laying hens under normal ambient(20 ~$26^{\circ}C$ ) condition.

• Korean Journal of Poultry Science
• /
• v.49 no.4
• /
• pp.239-246
• /
• 2022

This study was conducted to investigate the effects of dietary γ-aminobutyric acid (GABA) and a probiotic mixture on egg production and quality, blood parameters, and stress levels (corticosterone) in Hy-Line parent stock during summer in Korea. A total of 105 Hy-Line parent stock aged 24 weeks were randomly divided into three groups, each containing thirty-five birds: control, γ-aminobutyric acid (GABA), and probiotics (1 × 10⁸/g Bacillus licheniformis, 1 × 10⁷/g Lactobacillus plantarum, and 1 × 10⁷/g Corynebacterium butyricum). The hens were fed a diet containing 50 ppm GABA or 0.1% probiotics for 6 weeks. Compared with the control group, the hen-day egg production, egg mass, and feed conversion ratio over the total period were significantly higher in the probiotic group (P<0.05). In contrast no significant differences were detected among groups with respect to egg weight, albumen height, Haugh units, yolk color, shell thickness or shell strength. Similarly, no significant difference were observed among groups with regards to biochemical profile (total cholesterol, triglyceride, glucose, total protein, aspartate aminotransferase, alanine aminotransferase, albumin, and inorganic phosphorus). However, compared with the control group, we did detect significant reductions in corticosterone levels in the GABA and probiotics groups (P<0.05). On the basis of our findings in this study, it would appear that dietary GABA and probiotics can alleviate heat stress in Hy-Line parent stock, with probiotics in particular being found to promote significant improvements in the hen-day egg production, egg mass, and feed conversion of laying hens during the summer season in Korea.

• Animal Bioscience
• /
• v.37 no.8
• /
• pp.1418-1427
• /
• 2024

Objective: This study aimed to investigate the efficacy of Bacillus-based probiotics supplemented at two different levels to modulate the productive performance, egg quality, tibia traits, and specific cecal bacteria counts of Hy-Line Brown layers from 25 to 37 weeks of age. Methods: A total of 216 twenty-five-week-old hens were randomly distributed into 3 experimental diets with 12 replicates of 6 birds per cage. Diets included basal diet supplemented with 0 (CON), 3×10⁸ (PRO1), or 3×10⁹ (PRO2) colony-forming unit (CFU) of the test probiotic containing Bacillus subtilis PB6, Bacillus subtilis FXA, and Bacillus licheniformis G3 per kilogram of feed. Results: Improved egg weights and mass at 29 weeks; and feed intake at 31 weeks (p<0.10) were noticed with the probiotic-supplemented PRO1 and PRO2 diets. Considering egg quality, the shell thickness, Haugh units, and yolk color were improved; but yolk cholesterol was lowered (p<0.05) with PRO1 and PRO2 diets at 29 weeks. At both 33 and 37 weeks, the egg-breaking strength, shell color and thickness, albumen height, Haugh units, and yolk color were improved; but yolk cholesterol was similarly lowered (p<0.05) with the PRO1 and PRO2 diets. Improved tibia Ca, ash, weights, and density; and raised cecal counts of Bifidobacteria and Lactobacilli (p<0.05) were noticed with PRO1 and PRO2 diets. Improved tibia P but reduced Clostridia counts (p<0.10) were also observed with the PRO1 and PRO2 diets. Conclusion: Probiotic supplementation of Bacillus subtilis PB6, Bacillus subtilis FXA, and Bacillus licheniformis G3 at 3×10⁸ CFU/kg of feed is adequate to significantly improve egg quality, lower yolk cholesterol, enhance several tibia traits, and raise the populations of beneficial cecal bacteria. Modest improvements in several productive parameters and tibia P but reduced Clostridia were also observed; and could warrant further investigation of probiotic effects beyond the current test period.

• The Korean Journal of Zoology
• /
• v.8 no.2
• /
• pp.89-127
• /
• 1965

1. This report is on the outcome of observation made up the breeding process of Narcissus flycatcher, Muscicapa narcissina zanthopygia, using 15 ness-boxes at Seoul and Kwang Nung Experimental forest in 1964, and the relevant feeding habit was studied by the collar method of wrapping the necks of thenestlings for 50-60 minutes or more in some cases from 1963 to 1964. 2. The Narcissus flycatcheris a common summer resident throughout Korea arriving at the end of April. The earliest data of arrival of this species in Seoul, is April 26, 1964. They migrate southward from the later part of September to early part of October. 3. In a week after their arrival , they start to build nest after a brief courtship. Male and female prepare their nest ina nestboxes in 4 or 5 days. Nests are usually found in the moss, which provide definite frame-work. The inner side of the nest is usually composed of roots of Gramineae or leaves of pine, oak or other broad leave tree. 4. The laying period is generally from the later part of April to the middle of June : and the number of eggs laid is from 3 to 8 , therefore 5 in average : eggs are pink with traces of milky yellow blending of light auburn and orange red spots and chicken-egg-like in shape. 5.The incubation takes place for 7-12 days from the middle part of May to the middle of June, in the order of male and female . The hatching rate tends to increase in proportion to clutch size. 6. The feeding period usually lasts 15 days in average from the early part of June to the middle of July and the feeding urge tends to increase in proportion to brood size. 7. The animals invading into their nest-boxes are red ants, chipmunks, bees , barkbeetles and philippine red-tailed shirkes, etc. 8. On the basis of analysis covering 714 birds in 31 nests, the food they consumed during the nesting period of nestlings were mostly of animal matters composing of : insect larvae form-39. 88% insect adult form 36.26%, insect pupae-0.19%, spider-17.75% and other animal matters 5.92% , Besides a small amount of plant pieces were found . As to the insect larvae, Lepidoptera was the largest in the content followed by Hymenoptera , Orthoptera and Coleoptera. As to the insect adult, Diptera was the largest in the content followed by Coleoptera, and Hymenoptera. In view of forest protection, noxious insect was of 69.38%, useful insect 4.39%, and spider 17.75%. 9. The rich assortment of its food, the ability of acquiring various insect (adults as well as larvae), its destruction of great numbers of harmful insects , and its quick assimilation artificial nesting with the nest-boxes of 2.5-3cm entrance hole employed, allow us to conclude that the flycatcher may be successfully employed in the elimination of fores pests. The above results are only that part obtained near Seoul in the middle of Korea, however, if we would extend the scheme to other broad areas using similar techniques, the nest-boxes could not only be well used by the birds, but also it would help to prevent the increase of harmful. insects.

• Korean journal of applied entomology
• /
• v.48 no.4
• /
• pp.541-546
• /
• 2009

The egg size and weight of the gray field slug, Deroceras reticulatum Muller, was $1.91{\times}2.19$ mm and 3.3 mg at $24^{\circ}C$, respectively. Its weight increased from newly laid eggs to adults for 17 weeks at four temperature regimes and was heaviest at $20^{\circ}C$, followed by 24, 16 and $28^{\circ}C$. Likewise, hatching rate of the egg batches was highest with 95% at $20^{\circ}C$, followed by 24, 16 and $28^{\circ}C$ with significant differences. The number of eggs in the batches was increased with 20 at $20^{\circ}C$ while it was only 10 at $28^{\circ}C$. The average accumulated egg-laying days was longest with 15 days at $20^{\circ}C$ while shortest with 9 days at $24^{\circ}C$. The range of egg-laying period was shortest with 84-134 days at $16^{\circ}C$ and longest at $20^{\circ}C$. Thus, the total number of eggs laid by adult D. reticulatum was highest with 217 at $20^{\circ}C$ and lowest with 105 at $16^{\circ}C$. The egg period was 12-19 days while the juvenile period and adult longevity were 51-68 days and 85-134 days, respectively. The life span of D. reticulatum from egg to adult was longest with 216 days at $20^{\circ}C$, followed by 193 days at $24^{\circ}C$, 170 days at $16^{\circ}C$ and 151 days at $28^{\circ}C$. Accordingly, the most favorable temperature for the oviposition, development and longevity of D. reticulatum is $20^{\circ}C$.

• The Journal of the Petrological Society of Korea
• /
• v.10 no.2
• /
• pp.106-120
• /
• 2001

The Busan area in the northeastern part of the Ogcheon metamorphic zone, Korea, consists mainly of Precambrian Busan and Bakdallyeong gneiss complexes, Ogcheon metamorphic rocks and Mesozoic granitoids. The Busan gneiss complex shows Heart-shaped distribution laying down eastward, and is surrounded by the Ogcheon metamorphic rocks in the central part of the Busan area. In this study structural examination on the main constituent rocks (Busan gneiss complex and Ogcheon metamorphic rocks) was conducted to clarify the geological structure of the Ogcheon metamorphic zone in the Busan area. It indicates that the geological structure was formed at least by three phases of deformation. (1) Dl deformation: the formative period of the structural units of WNW trend (Sanjeoteo, Busan-II, Busan-I, and Chungiu nappes) and the mylonitic foliations related to the compression of NNE-SSW direction, (2) D2 deformation: the differential E-W shortening and N-S extension period of the structural units of WNW trend related to the compression of E-W or WNW-ESE directions, (3) D3 deformation: the formative period of the kink or open folds of E-W trend related to the compression of N-S direction in the eastern and southern parts of Busan area where the structural units of N-S or NNE trends reoriented owing to the intense D2 deformation were developed. These three phases of deformation are closely connected with the distribution of the structural units and the Heart-shaped Busan gneiss complex laying down eastward, and in this paper a new geodynamic model to the Heart-shaped Busan gneiss complex is suggested: Dl deformation-the zonal distribution of WNW trend with a constant width, D2 deformation - the formation of convex wedges northeastward and southward, D3 deformation - the formation of concave wedge westward.

• Korean Journal of Poultry Science
• /
• v.39 no.3
• /
• pp.177-182
• /
• 2012

This work was carried out to investigate the performance of growing period of two-way crossed of Korean native chickens parental stocks. A total of four hundred eighty female 2-crossbred chicks were used in this study and they were from National Institute of Animal Science. Groups were four crossbreds (4 replications/crossbred, 30 birds/replication) as A) C strain ${\times}$ Y strain, B) C strain ${\times}$ L strain, C) C strain ${\times}$ G strain and D) C strain ${\times}$ W strain. Body weight of A crossbred was the highest at the age of 8 week (P<0.05) and that of D strain was the lowest for growing period (P<0.05). Body weights of A and B crossbreds were higher than those of C and D crossbreds at the 12 and 16 weeks (P<0.05). Weekly body weights of A and B crossbreds were higher than C and D crossbreds (P<0.05), and weekly body weight of B crossbred was higher compared to other crossbreds at 0~20 weeks old. Weekly feed intake of D crossbred was the lowest among all crossbreds at 0~12, 0~16 and 0~20 weeks old (P<0.05). Weekly feed conversion ratio of C crossbred was the highest among crossbreds (P<0.05). These results can give the basic information for growth related data in 2-way crossbreed Korean Native Chickens, which can be used for the parental stocks for the laying-type of Korean native commercial chickens.

• Korean Journal of Poultry Science
• /
• v.34 no.3
• /
• pp.197-205
• /
• 2007

This study was conducted to compare the effect of feeding molting and fasting molting on the performance, egg quality, and visceral organs in laying hens for animal welfare. Eighty one 62-wk-old White Leghorn hens that egg production was over 80% and average weight was $1.6{\pm}0.3\;kg$ were used in this study. Treatments were control (non-molt treatment), feeding molt treatment, and fasting molt treatment. The three treatments were administered to three replicate group of nine hens wherein each group. All treatment groups were fed the basal diet (CP 15%, ME 2,700 kal/kg) for two weeks as the adaptation period. Induced molt diets contains low CP (6.7%) and low energy (2,200 kal/kg). Test periods were 14 days for feeding molting and 10 days for fasting molting. Egg production decreased to be 0% at 10 days of feeding molting treatment, but at 2 or 3 days of fasting molting treatment. Egg production restarted after 19 days ending molt at feeding molting treatment, while after 24 days at fasting molting treatment. On the egg quality was improved at molting treatments (p<0.05) except egg yolk. Egg shell tissue was crowded at molting treatment to compare to control. Liver weights, heart weight, and oviduct weight of laying hens decreased at molting treatments (p<0.05). Finally, feeding molting might could be replaced fasting molting on the welfare and further studies were needed about molting program.

• Korean Journal of Poultry Science
• /
• v.34 no.3
• /
• pp.157-163
• /
• 2007

To examine the effects of dietary organic selenium and vitamin E supplementation on egg production, egg weight, daily egg mass, feed intake, feed conversion, egg quality, lipid-soluble antioxidative capacity (ACL) in egg yolk, and selenium retention of egg in laying hens, Hy-Line laying hens of 77 wk old were replaced in the individual cage for 12 week. A corn-soybean meal based diet was supplemented with 0 (control), vitamin E 100 IU/kg and the combination of 0.9 ppm Se from selenium yeast (SY) and vitamin E 50, 100 and 150 IU/kg. Egg production and daily egg mass were significantly increased (P<0.05) in supplemental vitamin E 100 IU, and 0.9 ppm SY + vitamin E 50 IU than control for the whole experimental period. However, feed intake and feed conversion were not affected by supplemental vitamin E and SY. Haugh unit was significantly (P<0.05) higher in supplemental vitamin E 100 IU and 0.9 ppm SY + vitamin E 50 IU than control, 0.9 ppm SY + vitamin E 100 and 0.9 ppm SY + 150 IU in week 5. Haugh unit of the eggs during storage decreased significantly(P<0.05) from day 1 to day 11. However, Haugh units of the eggs from 0.9 ppm SY + vitamin E 150 IU treated groups did not decreased significantly until day 5. Yolk color was significantly (P<0.05) higher in 0.9 ppm SY + vitamin E 50 and 0.9 ppm SY + 100 IU than other treatment groups in week 1. Selenium concentrations of egg were significantly increased (P<0.05) in 0.9 ppm SY + vitamin E than control and vitamin E 100 IU groups. Lipid-soluble antioxidative capacity (ACL) in egg yolk was significantly (P<0.05) higher in supplemental combination of 0.9 ppm SY + vitamin E 150 IU when compared to those of other treatment groups.

• Journal of Animal Science and Technology
• /
• v.45 no.3
• /
• pp.369-376
• /
• 2003

This experiment was conducted to investigate the influence of different levels of metabolizable energy (ME) and crude protein (CP) on post-molt performance and egg quality of spent laying hens. Four hundred and thirty two, ISA Brown hens at sixty six weeks of age after molt induction were fed six experimental diets containing three ME (2,750, 2,800, 2,850 kcal/kg) with two CP (15, 17%) levels in a factorial design. The influence of ME and CP were evaluated on egg production, egg weight and feed intake throughout 24 weeks of production. Egg mass and feed conversion ratio (FCR) were measured during the experimental period. Haugh unit, yolk color and eggshell breaking strength were measured at 5%, 50%, peak, post peak and end stage of egg production. The hens fed 2800 kcal/kg diet along with 15% CP recorded the highest outcome of egg production (P<0.05). The egg weight has been shown to increase with hens receiving 2,800 kcal/kg ME. Daily egg mass tended to increase in hens fed with 15% CP and 2,800 kcal/kg ME. Feed intake decreased significantly with the level of ME and CP in the diet increased (P<0.05). Yolk color was improved significantly in eggs laid by the hens receiving 17% CP than 15% diet. It also tended to be higher in 17% CP with 2,800 or 2,850 kcal/kg ME diet treatments. Egg shell breaking strength increased with hens receiving diets of 15% CP and 2,800 kcal/kg. From this experiment it can be concluded that the ME level of 2,800 kcal/kg coupled with 15% CP could be used to achieve the higher egg production and better eggshell strength in induced molting hens.