• Animal Bioscience
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• 제34권11호
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• pp.1794-1801
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• 2021

Objective: The study aimed to evaluate the productive performance, carcass yield, size of digestive organs and nutrient utilization in Mexican Creole chickens, using four diets with different concentrations of metabolizable energy (ME, kcal/kg) and crude protein (CP, %). Methods: Two hundred thirty-six chickens, coming from eight incubation batches, were randomly distributed to four experimental diets with the following ME/CP ratios: 3,000/20, 2,850/19, 2,700/18 and 2,550/17. Each diet was evaluated with 59 birds from hatching to 12 weeks of age. The variables feed intake (FI), body weight gain (BWG), feed conversion (FC), mortality, carcass yield, size of digestive organs, retention of nutrients, retention efficiency of gross energy (GE) and CP, and excretion of N were recorded. Data were analyzed as a randomized block design with repeated measures using the GLIMMIX procedure of SAS, with covariance AR (1) and adjustment of degrees of freedom (Kendward-Roger), the adjusted means were compared with the least significant difference method at a significance level of 5%. Results: The productive performance variables BWG, mortality, carcass yield, fat and GE retention and excretion of N were not different (p>0.05) due to the diet effect. In the 3,000/20 diet, the chickens had lower values of FI, FC, crop weight, gizzard weight, retention, and retention efficiency of CP (p<0.05) than the chickens of the 2,550/17 diet. Conclusion: The Mexican Creole chickens from hatching to 12 weeks of age can be feed with a diet with 2,550 kcal ME and 17% CP, without compromising productive parameters (BWG, mortality, carcass yield) but improving retention and retention efficiency of CP.

• 한국축산식품학회지
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• 제42권5호
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• pp.833-848
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• 2022

The objective of this study was to characterize the meat quality traits that affect the texture and savory taste of Ufipa indigenous chickens by comparing the proximate composition, physical characteristics, collagen, and nucleic acid contents with those of commercial broilers. It was found that Ufipa chicken breast and thigh meat had a higher protein content (p<0.05) than broiler chicken meat, whereas the fat content was lower (p<0.01). The moisture content of thigh meat was lower in Ufipa chicken meat than in broiler chicken meat (p<0.05). Regarding meat color, broiler chickens had considerably higher L^* and b^* than Ufipa chickens in both the breast and the thigh meat, except for a^* (p<0.01). Regarding water holding capacity, Ufipa chicken breast exhibited higher drip loss but lower thawing and cooking losses than broiler chicken (p<0.01). In contrast, its thigh meat had a much lower drip and thawing losses but higher cooking losses (p<0.01). The shear force of Ufipa chickens' breasts and thighs was higher than that of broiler chickens (p<0.05), while the amount of total collagen in the thigh meat was higher than that of broiler chickens (p<0.05). Additionally, the inosine-5'-monophosphate (IMP) of Ufipa chicken breast and thigh meat was higher than that of broiler meat (p<0.05). The principal component analysis of meat quality traits provides a correlation between the proximate and physical-chemical prosperties of both breeds with some contrast. In conclusion, the present study provides information on healthy food with good-tasting Ufipa indigenous chickens, which offer a promising market due to consumers' preferences.

• 한국환경과학회지
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• 제31권5호
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• pp.457-460
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• 2022

This study was conducted to investigate the effects of dietary supplementation with Ptecticus tenebrifer powder on the mortality and meat quality of Korean native chickens. A total of 40,000 Korean native chickens (1 day old, Hanhyup No. 3) were allocated to two dietary treatments (20,000 chickens in each treatment), which were fed the following: basal diet (control) and 1% of Ptecticus tenebrifer powder (T1). Feeding trials were conducted for 12 weeks, and mortality was measured weekly. At the end of the experimental period, 16 chickens (8 chickens in each treatment) were selected and slaughtered to obtain breast meat. The items used to analyze meat quality were pH, TBARS, and meat color. The weekly mortality rate was decreased by around 2 to 3 times in the T1 treatment group compared with the control group. The pH, TBARS, L^*, and b^* values of Korean native chicken breast were not affected by Ptecticus tenebrifer powder supplementation (p>0.05); however, a^* values showed statistical significance (p<0.05). In conclusion, the addition of 1% Ptecticus tenebrifer powder reduced mortality rate and demonstrated its potential in livestock environmental management.

• Animal Bioscience
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• 제35권12호
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• pp.1904-1910
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• 2022

Objective: This study aimed to investigate the effects of corticotropin-releasing factor (CRF) on the feed intake of broiler chickens and explore its influencing mechanism. Methods: The study included two trials. In trial 1, 32 male broiler chickens (Arbor Acres, Gallus gallus domesticus) were given ventricle buried tubes, and they were allowed to recover for 3 days. At 8:00 AM, intracerebroventricular (ICV) injection with CRF or normal saline was performed in 10-day-old broiler chickens, which were divided into the 5, 10, and 20 ㎍ and control (normal saline) groups according to the dose of CRF injection. In trial 2, chickens were divided into the 10 ㎍ and control group (physiological saline) to repeat trial 1. Results: Results of trial 1 showed that the cumulative amount of feed intake in the 10 or 20 ㎍ groups was considerably lower than that of the control group after ICV injection with CRF. The lowest amount of feed intake was obtained with the addition of 10 ㎍ of CRF. In trial 2, the expression of ghrelin in the hypothalamus injected with 10 ㎍ of CRF increased significantly, but the expression of ghrelin in various sections of the small intestine considerably decreased. The expression of CRF receptor subtypes 1 (CRFR1) in the hypothalamus and some parts of the small intestine remarkably increased, and the expression of CRF receptor subtypes 2 (CRFR2) increased only in the duodenum, whereas the expression of growth hormone secretagogue receptor (GHSR-1α) in the jejunum and ileum increased considerably after ICV injection of 10 ㎍ of CRF. Conclusion: The CRF at 10 ㎍ increased ghrelin expression in the hypothalamus and CRFR1 expression in the small intestine, and this phenomenon was related to the suppressed feed intake of broiler chickens.

• Animal Bioscience
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• 제37권1호
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• pp.61-73
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• 2024

Objective: The main objective of this study was to define molecular mechanisms associated with thermal stress responses of chickens from commercial broilers (BR, Ross 308), Thai native chickens (NT) and crossbreeds between BR×NT (H75). Methods: Twenty days before reaching specific market age, chickens from each breed were divided into control and thermal-stressed groups. The stressed groups were exposed to a cyclic thermal challenge (35℃±1℃ for 6 h, followed by 26℃±1℃ for 18 h) for 20 days. Control group was raised under a constant temperature of 26℃±1℃. Pectoralis major (n = 4) from each group was collected for transcriptome analysis using HiSeq Illumina and analysis of glycogen and lactate. Gene expression patterns between control and thermal-stressed groups were compared within the same breeds. Results: Differentially expressed transcripts of 65, 59, and 246 transcripts for BR, NT, and H75, respectively, were revealed by RNA-Seq and recognized by Kyoto encyclopedia of genes and genomes database. Pathway analysis underlined altered glucose homeostasis and protein metabolisms in all breeds. The signals centered around phosphatidylinositol 3-kinase (PI3K)/Akt signaling, focal adhesion, and MAPK signaling in all breeds with slight differences in molecular signal transduction patterns among the breeds. An extensive apoptosis was underlined for BR. Roles of AMPK, MAPK signaling and regulation of actin cytoskeleton in adaptive response were suggested for H75 and NT chickens. Lower glycogen content was observed in the breast muscles of BR and NT (p<0.01) compared to their control counterparts. Only BR muscle exhibited increased lactate (p<0.01) upon exposure to the stress. Conclusion: The results provided a better comprehension regarding the associated biological pathways in response to the cyclic thermal stress in each breed and in chickens with different growth rates.

• Asian-Australasian Journal of Animal Sciences
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• 제18권5호
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• pp.747-754
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• 2005

Nutritional regulation of gene expression associated with growth and feeding behavior in avian species can become an important technique to improve poultry production according to the supply of nutrients in the diet. Insulin-like growth factor-I (IGF-I) found in chickens has been characterized to be a 70 amino acid polypeptide and plays an important role in growth and metabolism. Although it is been well known that IGF-I is highly associated with embryonic development and post-hatching growth, changes in the distribution of IGF-I gene expression throughout early- to late-embryogenesis have not been studied so far. We revealed that the developmental pattern of IGF-I gene expression during embryogenesis differed among various tissues. No bands of IGF-I mRNA were detected in embryonic liver at 7 days of incubation, and thereafter the amount of hepatic IGF-I mRNA was increased from 14 to 20 days of incubation. In eyes, a peak in IGF-I mRNA levels occurred at mid-embryogenesis, but by contrast, IGF-I mRNA was barely detectable in the heart throughout all incubation periods. In the muscle, no significant difference in IGF-I gene expression was observed during different stages of embryogenesis. After hatching, hepatic IGF-I gene expression as well as plasma IGF-I concentration increases rapidly with age, reaches a peak before sexual maturity, and then declines. The IGF-I gene expression is very sensitive to changes in nutritional conditions. Food-restriction and fasting decreased hepatic IGF-I gene expression and refeeding restored IGF-I gene expression to the level of fed chickens. Dietary protein is also a very strong factor in changing hepatic IGF-I gene expression. Refeeding with dietary protein alone successfully restored hepatic IGF-I gene expression of fasted chickens to the level of fed controls. In most circumstances, IGF-I makes a complex with specific high-affinity IGF-binding proteins (IGFBPs). So far, four different IGFBPs have been identified in avian species and the major IGFBP in chicken plasma has been reported to be IGFBP-2. We studied the relationship between nutritional status and IGFBP-2 gene expression in various tissues of young chickens. In the liver of fed chickens, almost no IGFBP-2 mRNA was detected. However, fasting markedly increased hepatic IGFBP-2 gene expression, and the level was reduced after refeeding. In the gizzard of well-fed young chickens, IGFBP-2 gene expression was detected and fasting significantly elevated gizzard IGFBP-2 mRNA levels to about double that of fed controls. After refeeding, gizzard IGFBP-2 gene expression decreased similar to hepatic IGFBP-2 gene expression. In the brain, IGFBP-2 mRNA was observed in fed chickens and had significantly decreased by fasting. In the kidney, IGFBP-2 gene expression was observed but not influenced by fasting and refeeding. Recently, we have demonstrated in vivo that gizzard and hepatic IGFBP-2 gene expression in fasted chickens was rapidly reduced by intravenous administration of insulin, as indicated that in young chickens the reduction in gizzard and hepatic IGFBP-2 gene expression in vivo stimulated by malnutrition may be, in part, regulated by means of the increase in plasma insulin concentration via an insulin-response element. The influence of dietary protein source (isolated soybean protein vs. casein) and the supplementation of essential amino acids on gizzard IGFBP-2 gene expression was examined. In both soybean protein and casein diet groups, the deficiency of essential amino acids stimulated chickens to increase gizzard IGFBP-2 gene expression. Although amino acid supplementation of a soybean protein diet significantly decreased gizzard IGFBP-2 mRNA levels, a similar reduction was not observed in chickens fed a casein diet supplemented with amino acids. This overview of nutritional regulation of IGF-I and IGFBP-2 gene expression in young chickens would serve for the establishment of the supply of nutrients to diets to improve poultry production.

• 생명과학회지
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• 제21권5호
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• pp.684-692
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• 2011

본 연구는 브로일러의 성장능력을 촉진하기 위한 사료 내 이눌로프리바이오틱스의 적정 첨가수준을 결정하기 위하여 수행하였다. 부화 당일 로스계통(Ross 308)의 브로일러 수컷 320수를 4개의 처리구로 완전임의배치하여 35일 동안 사육하였다. 실험처리구는 대조구(무첨가구), 항생제 첨가구(avilamycin 8 ppm), 이눌로프리바이오틱스 200 ppm 첨가구 및 이눌로프리바이오틱스 250 ppm 첨가구로 구분하였다. 브로일러의 체중과 사료섭취량은 두개의 이눌로프리바이오틱스 첨가구가 대조구, 항생제 첨가구 보다도 높았고, 항생제 첨가구는 대조구에 비해서 높았으며 통계적인 유의차가 인정되었다. 전체 실험기간 동안 사료요구율은 대조구가 이눌로프리바이오틱스 첨가구와 비교할 때 유의하게 높았으나 항생제 첨가구와 이눌로프리바이오틱스 첨가구 사이의 통계적인 유의차는 없었다. 도체중, 도체율, 가슴살, 다리살의 무게는 이눌로프리바이오틱스 첨가구가 대조구, 항생제 첨가구에 비해서 유의하게 높았고, 이눌로프리바이오틱스 200 ppm, 250 ppm 첨가구 사이의 차이는 없었으나 항생제 첨가구는 대조구에 비해서 유의하게 높았다. 복강지방은 이눌로프리바이오틱스 첨가구가 유의하게 감소(19.08~23.30%)하였으며 혈액 면역물질과 흉선, F낭의 무게는 이눌로프리바이오틱스 첨가구가 대조구와 항생제 첨가구에 비해서 유의하게 증가하였다. 장내 유익한 Bifidobacteria와 Lactobacillu는 이눌로프리바이오틱스 첨가구가 대조구와 항생제 첨가구에 비해서 유의하게 증가하였으나 유해한 E. coli와 Salmonella는 그 반대로 나타났으며 통계적인 유의차가 인정되었다. 본 연구는 브로일러의 성장능력 향상을 위한 사료 내 이눌로프리바이오틱스의 적정 첨가수준은 200 ppm에서 결정될 수 있음을 보여준다.

• 한국가금학회지
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• 제22권3호
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• pp.167-178
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• 1995

The purpose of this research was to get basic information for the development of Korean native chicken industry by reviewing the current native chicken farm management and marketing situation of native chicken products(meat and eggs). The research was carried on the basis of the farm field survey covering 210 native chicken feeders out of 9 different local areas, and the results were as follows ; 1. Average raising size of native chicken flocks of sample farms was 1,787 heads and about 50% of those farms raised less than 500 heads chickens for self-sufficiency or on the side. 2. Most farmers made the decision to start on feeding native chickens in small scale with small amount of capital without sound feeding program, and their decision was mainly influenced by recommendation of mass-media( 19.5%) and neighbors (17.2%). 3. The average income per farm earned by raising the native chickens was 13,719 Won, and income per head of chicken was 8,800 Won. 4. About 40% of feeders expressed that the poor marketing management and lack of capital were the bottleneck to native chicken farm management. 5. About 70% of feeders evaluated the prospect of native chicken industry positively and so, about 60% of feeders hoped to expand the raising size in the future. 6. Most farmers directry made a bargain with marketer including middleman and enduser in selling the chicken products because there was not established special marketing system for native chicken products. 7. The sales age of native broiler was about 16~20 weeks and average body weight of broiler was 1.5~2.0 kg. And farm recieved price was not decided on the basis of each body weight or meat quality but only number of heads. 8. The average first egg-laying age of chickens was about 165 days and average annual laying rate was only about 56%. 9. In order to develop the successful Korean native chicken industry, followings are recommended ; 1) Reducing the production costs and increasing the productivity of native chickens should be carried out through technological research and development for sound feeding program of native chickens and sufficient fund supply. 2) Orderly native chicken marketing and pricing system should be established to give good vision about native chickens to farmers and to delight the consumers. 3) The measures for product differentiation including meat quality and nutritional value of native chicken products against other improved chickens should be actively taken by feeders and government.

• Asian-Australasian Journal of Animal Sciences
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• 제18권10호
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• pp.1445-1450
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• 2005

This experiment was conducted to evaluate the effect of feed withdrawal (F) and heat acclimatization (A) on malebroiler and -layer chickens responses to acute heat stress (AHS) at four weeks of age. Totals of ninety male chicks of broiler or layer type were randomly allocated into 30 pens of grower batteries with raised wire floors. Chicks were subjected to F and A three times a week through the first three weeks of age. At each time, feed withdrawal and heat acclimatization (T = $35^{\circ}C$) lasted for six and four hours, respectively. Feed consumption (FC), body weight (BW), and feed conversion ratio (FCR) were recorded weekly for broiler type chickens only. At four weeks of age, all groups of chickens were exposed to AHS (T = $39{\pm}1^{\circ}C$) for three hours. Before and after AHS challenge, body temperature (Tb), heterophil (H), and lymphocyte (L) counts were recorded, and H/L ratio was calculated. Antibody (Ab) response to sheep red blood cells (SRBC) was assessed from all treatments without being exposed to AHS. Group F of broiler-type chickens weighed less (p<0.05) compared to control group. Also, both A and F groups of broiler-type chickens consumed less (p<0.05) feed when compared to control group. Acute heat stress elevated Tb of all treatment groups, however the increase was more profound (p<0.001) in broiler chicks. Broiler chicks of both A and F groups showed a tendency to have higher (p = 0.08) Tb when compared to control group. Acute heat stress elevated (p<0.001) H/L ratio in both types of chickens. Broiler chicks maintained higher (p<0.001) H/L ratio. Both F and A groups reduced (p<0.01) the level of elevation in H/L ratio compared to control groups of both types of chickens. Neither A nor F group affected the Ab production in response to SRBC. However, there was a tendency towards higher Ab responses in F group when compared to other groups in both types of chickens. Results of the present study demonstrate that previous history of feed withdrawal or episodes of heat exposures improved chicks'physiological withstanding of AHS and a tendency to improved humoral immune response.

• 한국동물위생학회지
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• 제18권2호
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• pp.113-123
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• 1995

The present study was conducted to investigate the prevalent characteristics of Fowl Typhoid and antibiotic susceptibility of Salmonella gallinarum isolated from 56 infective or dead chickens of 20 egg laying farms in Kyung Buk province during the period from August to December 1994. 1. Among 416, 000 chickens of 92 flocks in 20 egg laying farms, 17, 360 chickens of 31 flocks were died of Fowl Typhoid. 2. Salmonella gallinarum was isolated from 56 chickens in liver and spleen, and then blood of infective chickens was positive to Pullorum antigen. 3, In the survey of gross lesion of 56 chickens, 43 chickens(76.8%) were swelled at liver, 39(69.6%) were swelled at spleen, 12(21.4%) were changed with bronze, 3(5.4% ) were hemorrhagic in peritoneal cavity. 4. In transmission pattern, 4 farms were outbreaked the entrance of chicken house at first, but the others were outbreaked at various place. They were transmitted at right and left directions in flock. 5. 2 farms confirmed at the early stage of infection were eradicated by removing infective chickens and administrating antibiotics, but 18 farms at chronic stage were not. 6. The biochemical properties of 112 Salmonella gallinarum from chickens were generally identical to those of the referance, but H$_2$S was not productive, cellobiose was fermentive. 7 Minimum inhibitory concentration(MIC) of 20 isolates was performed by using 21 antibiotics, MICs of Amikacin(Ak), Gentamicin(Gm), Kanamycin(Km), and Tetracycline (Tc) were below 1.6 ug/ml, Ampicillin(Am), Furazolidone(Fu) and Neomycin(Nm) were below 3.1 ug/ml, Cephalothin(Ce), Cefazoline(Cf) and Chloramphenicol(Cm) were below 6.3 ug/ml, Nalidixic acid(Na), Polymyxin(Po) and Rifampicin(Rf) were below 12.5 ug/ml, Penicillin (Pm) was below 25 ug/ml, Colistin(Co) and Streptomycin(Sm) were below 50 ug/ml, Sulfamerazine(Sr) and Sulfamethazine (St) were below 200 ug/ml, Lincomycin(Lm) and Spiramycin(Sp) were below 400 ug/ml, Bacitracin(Ba) was below 800 ug/ml. 8. Among the 20 isolates, all(100%) of those were sensitive to Ak, Am, Ce, Cf, Cm, Fu, Gm, Km, Na, Nm, Po, Rf, Sr, St and Tc, but 6 isolates(30%) were resistent to Co, 20(100% ) to Ba, Lm, Pm, Sm, and Sp. The drug resistance patterns were simple which 6 strains were BaCoLmPmSmSp type, and 14 were BaLmPmSmSp type.