딱정벌레목(Coleoptera) 거저리과(Tenebrionidae)에 속하는 외미거저리(Alphitobius diaperinus (Panzer))는 저장곡물해충의 하나로 알 려져 있지만, 대부분 이미 피해를 받은 곡물을 섭식하기 때문에 경제적으로 심각한 위협을 초래할 정도는 아니다. 그러나 이 외미거저리 해충은 많은 나라의 가금산업에서 매우 중요한 해충으로 간주되고 있다. 우리나라의 육계농장에서도 외미거저리가 발생하여 문제를 야기하고 있음이 확 인되었고, 이 해충의 발생으로 야기되는 문제로는 육계농장의 보온효과 및 병아리의 전반적인 활력을 떨어뜨리고, 병원균을 전염시킴으로써 가 금업자에게 상당한 경제적 손실을 가져다주고 있다. 한편, 육계농장에서 이 외미거저리 개체군을 한 가지 방법으로 완전히 제거하기가 쉽지 않기 때문에 적절한 방제방법을 개발하기 위한 노력이 절실하다.

The purpose of this study was to determine the effects of mixed or split-sex feeding on growth performance and behavior of Korean native chickens. Three variants of the sex ratio, FO (female only), MO (male only) and MI (mixed) were tested in Korean native chickens (Hanhyop 3) that were between the ages of 7 and 91 days. Body weight gain was the highest (p<0.05) in the MO treatment and the lowest (p<0.05) in the MI treatment. The feed intake (FI) of birds in the MO treatment was higher (p<0.05) than that of birds in the MI treatment during days 14-21, also MO treatment was higher (p<0.05) than that of birds in the MI treatment during days 21-28. However, the FI of birds in the MI group was higher (p<0.05) than that of birds in FO treatment during days 35-42. The behavioral frequency of walking, drinking, and aggressive pecking were not affected by sex ratio treatment. The behavioral frequency of feeding was higher in the FO treatment than that of birds in the other treatments. The comfort time of birds in the MI treatment was longer (p<0.05) than that of birds in the other treatments. The behavioral frequency of pecking was higher in the MO treatment than that of birds in the other treatments. The study suggests that when male and female Korean native chickens are reared together, sex ratio can influence growth performance and behavior frequency.

To extend the shelf-life of chicken breast meat, samples were treated with gel-packs containing slow-released ClO2 gas at 7-15 ppm for 8 days at 4℃. And the changes in lipid oxidation and taste compounds of the samples were investigated. TBARS value of the chicken breast was slightly increased during storage. TBARS value of gas treatments was similar to the control during storage. There were 14 fatty acids in the chicken breast. And there was no change in the fatty acid composition during storage, and there was no significant difference between the control and gas treatments. The content of free amino acids was gradually increased during storage. The content of free amino acids were not significantly different between the control and gas treatments during storage. The content of GMP in the control and gas treatments were decreased during storage. However, gas treatments showed slightly higher content than that of control. AMP was not significantly different between the control and gas treatments. IMP gradually decreased during storage and the content of inosine and hypoxanthine was increased. IMP, inosine and hypoxanthine contents of gas treatment were similar to control, but the control tended to change more rapidly than those of gas treatments.

In this study, effects of gelatin extracted from chicken feet powder and wheat fiber on physicochemical properties of gel were determined. Gel samples were prepared with different concentrations of chicken feet gelatin powder (2, 3, and 4%) and wheat fiber (0, 1, and 2%). Gel strength increased (p<0.05) with increasing concentrations of both chicken feet gelatin powder and wheat fiber. In each gel sample, melting point and apparent viscosity of the gel was affected by different chicken feet gelatin powder concentrations irrespective of the wheat fiber concentrations (0, 1, or 2%). The 4% chicken feet gelatin powder induced the highest melting point among all gel samples regardless of the wheat fiber concentration. The gel sample with 4% chicken feet gelatin powder and 2% wheat fiber showed the highest values (p<0.05). With the increasing concentrations of wheat fiber, CIE L* increased in gel samples with chicken feet gelatin powder at 3 and 4% (p<0.05). Lower CIE a* was observed in gel samples with wheat fiber at 1 and 2% compared to gel samples without wheat fiber (p<0.05). CIE b* of gel samples with 2% chicken feet gelatin powder was decreased as increasing the addition level of wheat fiber (p<0.05). Consequently, our studies show that chicken feet gelatin powder and wheat fiber mixture could be used as a food ingredient since they have various effects on physicochemical properties of gel such as an effect on gel strength, melting point, viscosity, and color.

Red mite, Dermanyssus gallinae is one of the serious pests, damaging to the egg production in chickens. Moreover, the overuse of chemical insecticides caused pest resistance and environmental residual toxicity. Therefore, this work provides a screening method to select entomopathogenic fungi as a candidate of environmentally safe control agent, having high miticidal activity against D. Gallinae. The virulence test was conducted using a spraying method. Of the several species, Beauveria species showed high virulence and mycosis were observed. Some isolates were produced on eight cereal grains in Petri dish conditions. Millet, perilla seed and barley showed the high conidia production. Conidia of the isolates produced on millet and rice showed high thermal stability, when exposed to 45℃. Based on these results, this work suggests that entomopathogenic fungi could be used to control the D. Gallinae.

This study was conducted to evaluate the acceptability of cured cooked boneless chicken drumettes as a raw material for Chuncheon Dakgalbi and to observe its effect on pH, lipid oxidation, volatile basic nitrogen (VBN) content and total viable count (TVC) during refrigerated storage under vacuum. Boneless chicken drumettes were dry cured with a mixed curing agent (0.20% w/w) consisting of sodium chloride (93.1%), sodium nitrite (5.9%) and sodium bicarbonate (1.0%) for 24 h at 2±2℃. Cured samples were cooked using an oven at 150℃ for 20 min and stored at 5.5±0.5℃ for 60 days under vacuum. Non-cured cooked sample was used as a control. Sensory evaluation was performed on day 2 of storage using 22 untrained panelists and samples were mixed with Dakgalbi sauce and reheated using a microwave for 2 min. There were no significant differences between control and treatment group on appearance, flavor, texture, juiciness and overall acceptability. Cured cooked boneless chicken drumettes had significantly (p<0.05) higher pH, lower lipid oxidation, VBN and TVC consistently during storage in comparison with control. These results suggest that dry curing could be applied to boneless chicken drumettes as raw material for Chuncheon Dakgalbi and could extend its shelf life during refrigerated storage under vacuum.

The deleted in azoospermia like (DAZL) gene has been identified in many vertebrate species. DAZL shows high homology with deleted in azoospermia (DAZ) genes that identified only in humans, great apes and Old World monkeys, and boule homolog (BOLL) that identified in many vertebrate species. These genes encode RNA binding proteins (RBP), which regulate the post-transcriptional functions of several genes. In humans, DAZ copies are linked to Y chromosome, while DAZL and BOLL are linked to chromosomes 3 and 2, respectively. DAZ copies has been reported to express in prenatal and postnatal germ cells, particularly in the premeiotic spermatogonia. BOLL has been reported to express during the meiotic G2/M transition in germ cells. DAZL has been reported to express in all stages of germ cells. Compared to humans and mice, the detailed functionalities of DAZL is not clear in many vertebrate species. In our studies, we use chickens as an animal model to examine the expression profiling of DAZL gene in germ cells right from the early embryonic development to the adult. Also, we are studying the effects of small interfering RNA (siRNA) mediated knockdown of DAZL and Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR)/CRISPR associated protein 9 (CRISPR/Cas9) mediated knockout of DAZL in the chicken primordial germ cells (PGCs). In the chicken, DAZL is linked to chromosome 2 (2p1.3-p1.2), and encodes a 289 amino acids protein. By in situ hybridization, we detected a strong expression of DAZL in the germ plasm of chicken oocytes. Later, the expression of DAZL was strongly detected in all stages of intrauterine development and post-ovipositional development especially in the PGC specifying cells. Moreover, the expression of DAZL was strong and constant in the male and female germ cells until adult stage. The siRNA mediated knockdown of DAZL significantly reduced the PGCs proliferation and increased the apoptosis in vitro. We examined the knockout efficiency of DAZL using CRISPR/Cas9 technique in chicken DF1 fibroblast cell line, prior to test in the PGCs. The results of T7 endonuclease I (T7E1) assay and subsequent sequencing indicates clear mutations on the DAZL gene in DF1 cells, and the method could be applicable to cause mutations on the DAZL gene in PGCs. In conclusion, chicken DAZL express in all stages of germ cells as a germ line marker, and alteration in the gene expression causes germ cells impairment.

Epizootic HPAIV, H5N6, and H5N8 infections produced severe loss in poultry and wild birds in the Republic of Korea from 2016 to 2017. But pathological lesions and antigen distribution of the novel HPAIV H5N6 clade 2.3.4.4 in natural cases have been rarely reported. Herein, we describe the pathological lesions and antigen localization in chickens (layer and Korean native), ducks, and Japanese quail naturally infected by HPAIV H5N6. Grossly, severe reddening, swelling, and some necrotic foci, which were similar to septicemia or viremia, were observed in skin and many visceral organs including trachea, lung, liver, spleen, and pancreas. Histopathologically, pulmonary congestion and edema, as well as necrotizing hepatitis, splenitis, pancreatitis, myocarditis, and encephalitis were observed. Immunohistochemically, numerous HPAIV antigens were detected in necrotic parenchymal cells and in blood vessels of the respiratory, lymphoid, digestive, urinary, nervous, and cardiovascular systems. The results indicate that HPAIV H5N6 spread to the entire body via blood and caused severe damage throughout the entire body. The HPAI H5N6 clade 2.3.4.4 virus was isolated from samples of all four cases.

본 연구에서는, 표고버섯 균사체 발효 생물전환공법으로 생산된 미강생물전환소재(BPP-RB)가 가금티푸스의 주요 원인균인 S. Gallinarum에 감염된 닭 유래 대식세포주 HD- 11에 미치는 효과를 조사하였다. 그 결과, 미강생물전환소 재 추출액은 S. Gallinarum 277에 대한 직접적인 성장억제 효과를 보여주지 않았으며, 총단백질 및 분비단밸질 발현 양상에 어떠한 변화도 유도하지 못하였다. 하지만, 미강생 물전환소재 추출액은 (i) HD-11 대식세포의 탐식 능력 (phagocytic activity)을 활성화하였고, (ii) Th1-type cytokines (tumor necrosis factor-α, interleukin (IL)-1β, iNOS)과 immunosuppressive cytokine IL-10의 발현 증가를 유도하였으며, (iii) Th2-type cytokines (IL-4, IL-6)의 발현은 감 소시키는 것으로 확인되었다. 이러한 결과를 종합하면, 미강생물전환소재는 가금 농장에서 가금티푸스 및 다른 Salmonella종의 감염을 예방하기 위한 사료첨가제로서의 가능성을 가지고 있다고 사료된다.

본 연구는 고온다습한 하절기에 음수의 형태가 닭의 생산성, 육질, 혈액의 성상에 미치는 영향을 구명하고자 실행하였다. 8일령 로스종 360수를 4개 처리구인 수돗물, 이온수, 냉수 및 냉이온수(냉수+이온수)로 처리구당 6반복으로 평사에 수용하여 5주령까지 급수하였다. 계사내부 평균 온도와 습도는 30.9℃와 74.0%였으며, 수돗물의 평균온도는 29.5℃였다. 이온수는 정전기를 이용하여 물을 이온화하였고, 냉수는 15℃로 고정하여 급수하였다. 증체량, 사료섭취량 및 사료요구율은 주간으로 측정하였으며, 혈액과 계육 샘플은 실험 종료시에 채취하였다. 사육전기 21일령에 증체량은 수돗물 처리구에서 다른 처리구에 비하여 낮았지만 통계적 차이는 없었으며, 사육후기의 35일령에 이온수, 냉수, 냉이온수 처리구에서수돗물 처리구에 비하여 현저하게 높게 나타났다(p<0.01). 사료섭취량은 증체와 동일하게 사육전기에는 처리구간에 일관적 차이가 없었지만 사육후기에 수돗물 처리구에 비하여 다른 처리구에서 매우 개선 되는 경향을 보였다(p<0.01). 사료요구율은 사양실험 전기간에서 이온수, 냉수 및 냉이온수 처리구에서 매우 개선되었다(p<0.05). 계육의 가슴살에서 명도는 수돗물 처리구에서 높게 나타났으며, 적색도는 낮은 경향을 보였다. 황색도는 일관성이 없었지만 pH는 수돗물 처리구에서 다른 처리구에 비하여 낮게 나타났다(p<0.05). 조리감량은 이온수, 냉수 및 냉이온수 처리구에서 수돗물에 비하여 매우 낮았지만(p<0.05) 연도는 높은 경향을 보였다. 혈중 알부민과 단백질은 처리구간에 차이가 없었지만, 중성지방은 이온수, 냉수 및 냉이온수 처리구에서 낮은 경향을 보였다(p<0.05). 혈중 포도당은 처리구간에 차이가 없었지만 HDL 콜레스테롤은 이온수, 냉수, 냉이온수 처리구에서 수돗물 처리구에 비해 현저하게 높게 나타났다(p<0.05). 본 실험 결과 혹서기 육계에 냉이온수 급수는 생산성 및 육질을 개선하고 혈중HDL을 높게 하였다.

While the darkling beetle, Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae) is considered a pest of stored products, it does not pose a significant economic threat to this industry. The grains these beetles feed on are often already damaged. However, the beetle is considered the foremost premise pest in the poultry industry in many countries of the world. Recently, the darking beetle has also infested in broiler chicken houses of Korea. The problems caused by this pest are destroying their insulative capability, lowering chick’s overall performance and transmitting pathogenic organisms, and have been substantial economic losses to poultry producers. Therefore, we surveyed the status of infestation and damage of this pest in broiler chicken houses. Because there is no simple one step process that will completely eliminate darkling beetle populations from broiler facilities, we would like to outline further studies on the proper control measures.

Developmental aspects of chicken embryos showed dramatic difference compared with those of mammals and consequently, such difference in various developmental events leads to different feasibility in both clinical and industrial application. We have concentrated on the studies for using of chicken bone marrow cells and currently we found number of unique cellular properties. Through this article, we reviewed characteristics and cell signaling of osteogenic cells during endochondral ossification in chicken long bone.

To prolong the shelf-life of chicken breast meat, samples were treated with gel packs containing slow-released chlorine dioxide (ClO2) gas at 7~15 ppm for eight days at 4℃. The microbial, physicochemical properties and sensory evaluation of the treated samples were investigated. The total number of bacteria in the control increased during storage and showed 6.78 log CFU/g on the 8th day of storage, but ClO2 gas treatments showed 6.24~6.58 log CFU/g at the same time. The initial pH of chicken breast meat was 6.00 and gradually increased during storage. And ClO2 gas treatments did not show any significant difference from the control during storage period, but maintained a generally lower pH than that of the control. The lightness, redness, and yellowness during storage were not significantly different between the control and the 7~10 ppm ClO2 gas treatments. However, as the storage period was increased, the redness of 15 ppm ClO2 gas treatment was reduced. The cooking loss and shear force were not different between the control and ClO2 gas treatments during the storage period. Volatile basic nitrogen (VBN) increased in the control from the 6th day of storage and 23.80 mg% in the 8th day of storage. However, VBN of ClO2 treatments showed lower than that of the control. In the change of sensory evaluation during storage, 10 ppm ClO2 treatment showed the highest preference in odor, appearance and overall acceptance during storage period.

The ability of antimicrobial resistant Salmonella strains to cause invasive disease can be attributed to various virulence genes. In this study, the virulence genes located in SPI-1, SPI-2, SPI-5, SPI-11 were found in all antimicrobial-resistant Salmonella isolates. This suggests that these genes play important roles in Salmonella invasion, growth, or survival in the host. The association between the presence of virulence genes and antimicrobial resistance was assessed using the Spearman’s correlation coefficient, and there is a positive association between the gatC, tcfA, hylE, spiA, pagC, msgA, invA, sipB, prgH, spaN, orgA, tolC, iroN, sitC, lpfC, and sopB genes, and resistance to CF, NA and S. This suggests that the association between antimicrobial agents and virulence genes has been shown to vary with the types of antibiotics that are commonly used in different countries. These different associations can be explained by the mechanisms underlying pathogenicity and the acquisition of resistance genes by Salmonella.

본 연구는 Bacillus subtilis를 포함하는 3개의 균주를 지렁이 분변토에 접종하여 제조한 생균제인 분변토 발효사료가 육계의 사양성적 및 닭고기 품질에 미치는 영향을 조사하기 위하여 수행하였다. 육계 240마리를 4개의 처리구로 완전임의 배치하였다. 실험 처리구는 대조구, Lactobacillus fermentum으로 제 조된 상업용 생균제 (CP) 0.2%, 분변토 발효사료 0.3% (FECF3), 분변토 발효사료 0.5% (FECF5)로 구분하였다. 평균 체중 증가량, 흉선, 비장, F낭의 무게는 대조구, CP 처리구와 비교할 때 FECF 처리구가 높았다. 혈액 IgG 함량은 대조구, CP 처리구와 비교할 때 FECF 처리구가 증가하였다. 맹장 Lactobacillus는 대조구, CP 처리구와 비교할 때 FECF 처리구가 높았으나 Escherichia, Salmonella, Coliform bacteria 및 total aerobic bacteria는 FECF 처리구가 낮았다. 닭고기의 보수력은 대조구, CP 처리구와 비교할 때 FECF 처리구가 높았다. 닭고기 n-6/n-3 지방산의 비율은 대조구, CP 처리구와 비교할 때 FECF 처리구가 낮게 나타났다.

With emphasis on native genetic resource, Korean native chicken is one of the major native breeds in poultry in Korea. The weight-age data from 216 pullets of Korean native chicken were used to fit the growth curve using Gompertz model. Live weights have been recorded every three weeks for 36 weeks for 5 strains. All available weight data from birth to the 6 specific ages of week were used for the estimation of parameters. The variation in estimates of mature weight (A) decreased with the increase of age 21 through 36 weeks for all 5 strains studied. However, the variation of rate of maturing (k) showed a tendancy increase with the increase of age. These results indicate that the fitting of growth curve is getting more stable for asymptotic value (A) and more flexible for curve shape (k) with the increase of weight-age data range. Correlations among estimates of A and among estimates of k at various ages showed the highest range of 0.93 ~ 0.99 between 30 and 36 weeks except for the maturing rate (k) of red brown strains. The correlations between A and k tended to fluctuate and were not significant statistically at various ages. Thus, the estimates of growth curve parameters, A and k suitable for genetic studies in Korean native chicken can be derived from accumulated weight-age data after 30 weeks of age.

병원성 대장균군은 전세계적으로 식중독을 발생하는 중요한 병원균으로 알려져 있다. 국내 유통중인 생닭과 조리된 닭가공품 356시료에서 대장균 80균주(22.5%)를 분리 하여 병원성 유전자 multiplex PCR를 이용하여 분석한 결 과 astA 유전자가 26균주(32.5%)에서 검출되었으며, escV 유전자는 17균주(21.3%) eaeA 유전자는 16균주(20.0%) 검 출되었다. 특히 식품에서 문제가 되는 장출혈성 대장균 유 전자 stx 1는 3균주(3.8%)와 stx 2, EHEC-hly는 각 1균주 (1.3%)에서 검출되었다. 병원성 유전자를 토대로 STEC, EPEC, EHEC, EIEC or EAEC의 병원성 대장균으로 분류 한 결과 45균주(56.3%)가 검출되었으며 typical EPEC, EIEC and ETEC의 병원성 대장균은 검출되지 않았다. STEC 병원성 대장균은 O152, O1, O116, O26, O25, O119, O153 혈청형이 분리되었다. 특히 생닭에서 병원성 대장균에 대한 검출률이 높으므로 생닭을 가공 조리 시 교차 오염이 발생하기 않도록 조리 도구, 조리 환경에 대한 철저 한 관리가 필요하다고 생각된다.

본 연구는 닭가슴살(5, 15, 25%)과 기계발골 계육(5, 15, 25, 35%)의 첨가 수준을 달리하여 제조한 소 시지의 품질특성을 조사하여 육가공제품의 원료로 적정 첨가 수준을 구명하고자 실시하였다. 닭가슴살을 첨가한 소시지는 수분과 단백질 함량이 증가하였으나, 지방함량이 감소하였다. 기계발골 계육 첨가는 소 시지의 수분과 단백질 함량을 감소시키고, 지방함량을 증가시켰다. 무기물의 경우 닭가슴살 첨가가 소시 지의 인, 나트륨, 구리 함량을 증가시켰으며, 기계발골 계육 첨가는 칼슘, 철 함량을 증가시켰다. 닭가슴 살 또는 기계발골 계육을 첨가한 소시지는 pH를 감소시켰다. 닭가슴살 첨가는 소시지의 명도를 증가시키 고, 적색도와 황색도를 감소시켰으며, 기계발골 계육을 첨가한 소시지는 명도가 감소하고, 적색도와 황색 도가 증가하였다. 조직감에서 닭가슴살 첨가는 경도, 탄력성, 검성, 씹힘성이 증가하였으나, 기계발골 계 육 첨가는 경도, 탄력성, 검성, 씹힘성을 감소시켰다. 관능적 특성에서 기계발골 계육 첨가는 저작감을 감소시켰다. 기계발골 계육 첨가는 육색에는 긍정적인 영향을 미치나, 조직감을 저해시키고 단백질 함량 을 낮추어, 기계발골 계육을 첨가할 경우 5% 이하로 첨가해야 할 것으로 사료된다.

The objective of this study was to explore the role of familiarity in cross-cultural product perception and perception changes according to food systems (hot sauce and spicy-chicken) in Korean and US consumers. Free choice profiling was conducted by Korean and US consumers on four spicy-chicken samples made using four hot sauce samples. Half of the hot sauce samples were selected to be more familiar to US consumers and vice versa to Korean consumers. A previous study that investigated cross-cultural perceptions of the same four hot sauce samples in US and Korean consumers was incorporated in this study. For distinct sample differences, US and Korean consumers perceived products similarly. However, for less obvious differences, flavor familiarity seemed to affect consumers’ product perceptions. In addition, product perceptions changed more dramatically according to food systems for familiar samples in each country. The findings of this study show that consumers’ product perception can be affected by flavor familiarities.