Background: This study explores the potential of discarded male layer embryos as a sustainable and non-GMO cell source for cultivated chicken meat production. The research aims to identify efficient methods for isolating muscle progenitor cells (MPCs) with high proliferative potential by conducting transcriptome analysis on thigh muscle tissues from both male and female chick embryos. Methods: Transcriptome analysis was performed on the thigh muscle tissues of male and female chick embryos, aged 12-13 days, (n = 4 each), to investigate the gene expression profiles and identify strategies for efficiently isolating MPCs. This approach aims to pinpoint techniques that would allow for the selection of MPCs with optimal growth and proliferation capabilities. Results: Using heatmap, hierarchical clustering, and multidimensional scaling (MDS), we found no significant sex-based differences in gene expression, except for the overexpression of the female-specific gene LIPBLL. The expression of muscle stem cell factors, including PAX3, PAX7, and other myogenic regulatory genes, showed no significant variation. However, to recover MPC-rich cells isolated from male thigh muscle, we found that by the pre-plating 7 stage, myogenesis-related genes, MYHs and MUSTN1 were minimally expressed, while the cell cycle arrest gene CDKN1A sharply increased. Conclusions: Our findings suggest that simple cell isolation directly from tissue is a more scalable and efficient approach for cultivated meat production, compared to labor-intensive pre-plating methods, making it a viable solution for sustainable research and resource recycling.

Salmonella enterica subsp. enterica serovar Gallinarum biovar Gallinarum causes fowl typhoid in poultry. In this study, we isolated Salmonella from a Korean retail chicken shell egg and performed whole-genome sequencing, from which we identified one chromosome (4,659,977-bp) and two plasmids (plasmid_1: 87,506 bp and plasmid_2: 2,331 bp). The isolate serotype was confirmed to be Gallinarum, with a biovar type of Gallinarum, which was finally identified as Salmonella enterica subsp. enterica serovar Gallinarum biovar Gallinarum. Multilocus sequence typing confirmed that the isolate was that of sequence type 78. The antimicrobial resistance gene, aac(6')- laa, was identified on the chromosome, and 166 virulence genes were detected on the chromosome and plasmid_1.

In this study, chicken fry was made using batter prepared from a frying pre-mix that replaced wheat flour (WF) with floury rice powder (FRP) at ratios of 0% (control group), 25% (FRP-25 group), 50% (FRP-50 group), 75% (FRP-75 group), and 100% (FRP-100 group). The physicochemical and acceptability of the finished chicken fry were assessed to provide basic data for product development studies using FRP. The experimental groups that replaced WF with FRP showed higher water binding capacity and lower fat binding capacity than the control group (p<0.05). The viscosity of the batter decreased significantly as the proportion of FRP increased (p<0.05). The pick-up rate measurement results showed significantly lower values in experimental groups compared to the control group (p<0.05). The color measurement results of the chicken fry showed that as the substitution ratio of FRP to WF increased, lightness decreased, and redness increased (p<0.05). The browning index also showed a significant increase as the substitution ratio of FRP increased. The acceptance test results showed that the FRP-100 experimental group was significantly higher in all acceptability characteristics than the control group (p<0.05).

Scaly-leg in chickens, also known as knemidokoptiasis, is caused by infection with Knemidokoptes spp. Chickens in backyard systems developed scaly skin lesions on their legs. This farm is not an industrialized farm for producing meat or eggs. A skin smear microscopic test identified the Knemidokoptes spp. mites, revealing both larvae and adults in the same chicken. Ivermectin was applied to control the knemidokoptiasis through oral and topical administration. However, there were no clinical effects observed after the application of ivermectin. Knemidokoptiasis worsens the quality of life in chickens. Effective control methods could be established in further studies.

This study investigated the quality characteristics of convenient chicken porridge prepared with fresh ginseng powder (FGP). The porridge made with the addition of FGP showed significantly higher or similar pH at 5.99-6.13 compared to porridge made without adding FGP. The convenient chicken porridge with FGP had lower viscosity and higher spreadability than the control group (p<0.05). This porridge exhibited higher lightness (L) and yellowness (b) values but a lower redness (a) value than the control group (p<0.05). The porridge made with the addition of 0.4% blanched FGP (BG0.4) displayed higher total polyphenol content, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activities than the other types of chicken porridge (all p<0.05). The porridge with the addition of FGP showed weaker “rice grain size”, “glossiness”, “appearance cohesiveness”, “cooked rice aroma”, “sweet taste”, “texture cohesiveness”, “thickness”, and “stickiness” than the control group (all p<0.05). The appearance and flavor acceptance were significantly higher or similar for the porridge samples made with the addition of 0.2% non-blanched FGP (NBG0.2) and 0.4% non-blanched FGP (NBG0.4) when compared with those of the control group.

Chicken embryonic stem (ES) cells have great potential and provide a powerful tool to investigate embryonic development and to manipulate genetic modification in a genome. However, very limited studies are available on the functional characterization and robust expansion of chicken ES cells compared to other species. Here, we have developed a method to generate chicken embryonic stem cell-like cells under pluripotent culture conditions. The chicken embryonic stem cell-like cells were cultivated long-term over several passages of culture without loss of pluripotency in vitro and had the specific expression of key stem cell markers. Furthermore, they showed severe changes in morphology and a significant reduction in pluripotent genes after siRNA-mediated NANOG knockdown. Collectively, these results demonstrate the efficient generation of chicken embryonic stem cell-like cells from EGK stage X blastoderm-derived singularized cells and will facilitate their potential use for various purposes, such as biobanking genetic materials and understanding stemness in the fields of animal biotechnology.

비가열 닭고기 분쇄육의 제조 시 향신료의 첨가에 의한 세균의 증식 억제 효과에 대하여 연구하였다. 닭가슴살 분 쇄육의 일반성분은 수분 72.98±0.15%, 조단백질 23.37±0.46%, 조지방 1.00±0.03%, 조회분 1.90±0.03%였다. 향신료 첨가 에 의한 미생물 증식 억제 효과는 로즈마리 > 마늘 > 겨 자 순이었으며, 첨가량이 증가할수록 억제 효과가 커졌다. 닭고기 분쇄육의 일반세균 및 대장균 증식 억제를 나타내 는 향신료의 최적 첨가 농도는 로즈마리 2%, 마늘 4%, 겨 자 1.2%였다. 일반세균 및 대장균에 대한 증식 억제 효과 는 단독 및 혼합 첨가 시 저장기간 동안 기간별로 차이가 있었고, 저장 9일째 억제 효과는 MixA(97.4%) > 로즈마 리(96.9%) > MixB(96.3%) > 마늘(53.7%) > 겨자(33.3%) 순이었다. 닭고기 분쇄육에 살균마늘과 비살균마늘을 첨가 하여 비교했을 때 일반세균 수는 살균마늘 처리구가 비살 균마늘 처리구에 비해 초기 2.6-3.0 log CFU/g, 9일째 2.4- 3.2 log CFU/g 정도 낮았고, 저장기간이 경과할수록 그 수 가 감소하였다. 비살균마늘 처리구는 대조구보다 높은 일 반세균 수를 나타냈으며, 저장기간이 경과할수록 증가하는 경향을 나타냈다. 대장균 수의 경우 살균마늘 처리구가 비 살균마늘 처리구에 비해 저장 0일째 0.4-1.0 log CFU/g, 9 일째 0.5-1.5 log CFU/g 정도 낮았으며, 저장기간의 경과에 따른 변화는 일반세균 수와 비슷한 경향을 나타냈다. 결론 적으로 로즈마리, 마늘, 겨자의 다양한 혼합적용에 의해 닭 고기 분쇄육 제품의 미생물적 안전성이 향상되었다.

This study investigated the quality characteristics of emulsion-type chicken breast sausages containing black soldier fly larvae (BSFL) powder. The chicken breast and BSFL powder were added at various mixing ratios (C:chicken breast 56% and BSFL powder 0%, 1%:chicken breast 55% and BSFL powder 1%, 2%:chicken breast 54% and BSFL powder 2%, 3%:chicken breast 53% and BSFL powder 3%). The pH, moisture content, and water holding capacity of the sausages increased with the powder amount. In the instrumental color evaluation, the L* and b* values were significantly different among the samples (p<0.05). However, there was no significant difference in a* value (P>0.05) with the amount of powder added. Volatile basic nitrogen and acid value tended to increase with the amount of BSFL powder. The total phenolic content tended to increase, but the value of IC50 according to DPPH radical scavenging decreased as the amount of powder increased. This study concluded that BSFL powder can be used in meat products processing as a substitute for meat protein and may also improve antioxidant activity.

본 연구는 흰점박이꽃무지 유충 분말의 첨가량에 따른 닭 가슴살 소시지의 품질특성에 대한 영향을 분석하였다. 분석 결과 흰점박이꽃무지 유충 분말 첨가 유화형 닭고기 소시지와 첨가하지 않은 대조구 간의 일반성분 차이는 보이지 않았다(p>0.05). 흰점박이꽃무지 유충 분말 첨가량에 따라 명도는 감소하고 황색도는 증가하는 경향을 보였으며, 흰점박이꽃무지 유충 분말의 높은 pH가 육제품의 pH를 상승시켜 가열감량은 감소시키고 보수력은 증가시키는 긍정적인 영향 을 보였다. 유화형 소시지의 물성 중 경도에서 흰점박이꽃 무지 유충 분말 첨가구가 대조구 보다 높은 값을 나타내 조직감에 변화를 주었으며, 자유라디칼 활성도와 총 페놀 함량은 흰점박이꽃무지 유충 분말의 첨가량에 따라 증가하는 경향을 보였다. 이러한 결과를 통해 흰점박이꽃무지 유충 분말의 우수한 항산화 활성이 육제품에서도 발현이 가능 하며 기능성 첨가물로서 흰점박이꽃무지 유충 분말을 활용 한 기능성 소시지 제조 또한 가능할 것으로 판단된다.

A number of Korean Chicken breeds were registered in Domestic Animal Diversity Information System (DAD-IS, http://dad.fao.org/) of the Food and Agriculture Organization (FAO). Evaluation of genetic diversity and relationship of local breeds is an important factor towards the identification of unique and valuable genetic resources. Therefore, this study aimed to analysis the genetic diversity and relationship of 22 Korean Chicken breeds using 12 microsatellite (MS) markers. The mean number of alleles for each variety was 5.52, ranging from a 3.75 (Leghorn F; NF) to a 7.0 (Ross). The most diverse breed was the Hanhyup3 (HCC), which had the highest expected heterozygosity (HExp) (0.754) and polymorphic information content (PIC) (0.711). The NF was the least diverse population, having the lowest HExp (0.467) and PIC (0.413). As a result of the principal coordinates analysis (PCoA) and factorial correspondence analysis (FCA) confirmed that Hy-line Brown (HL) and Lohmann Brown (LO) are very close to each other and that Leghorn and Rhode Island Red (RIR) are clearly distinguished from other groups. Thus, the reliability and power of identification using 12 types of MS markers were improved, and the genetic diversity and probability of individual discrimination were confirmed through statistical analysis. This study is expected to be used as basic data for the identification of Korean chicken breeds, and our results indicated that these multiplex PCR marker sets will have considerable applications in population genetic structure analysis.

Fowl adenovirus serotype-4 (FAdV-4) infection, also known as hydropericardium-hepatitis syndrome (HHS), is one of the most prevalent diseases in the Korean poultry industry. Therefore, an effective vaccination against FAdV-4 should be developed for prevention of HHS infection. However, a standard animal model with significant pathologic characteristics has not been established for evaluation of HHS vaccine efficacy. In this study, we comparatively evaluated FAdV-4 pathogenicity from specific- pathogen-free (SPF) chickens using FAdV-4 strain (ADL091024) isolated in laying chickens in Korea according to chicken age, passage number and virus titers. In brief, FAdV-4 passaged four times in yolk sac of SPF eggs with the highest viral titers could induce the most severe clinical signs in 1-day-old chickens, similar to natural HHS outbreaks. Furthermore, the efficacy of a newly developed attenuated live FAdV-4 vaccine candidate was successfully determined using the established 1-day-old SPF chickens. There was no significant pathogenicity based on the criteria such as mortality, body weight, gross lesions, histological lesions and virus detection rates in the vaccination and non-challenge control groups. However, the challenge group without vaccination showed significant pathogenicity including hepatic necrosis, histological lesion scores in the liver and heart, virus replication and decreased body weight gain. In conclusion, the chicken challenge model established in this report was proposed for consistent and reliable evaluation of FAdV- 4 vaccine efficacy.

본 연구는 감마선 및 전자선 조사에 의한 닭고기 원료 사료 내에 존재하는 주요 위해 미생물을 비열처리 살균 효과를 검증하기 위하여 진행되었다. 일반세균, E. coli 및 Salmonella의 위해 미생물을 분쇄 닭고기 원료사료에 접종 후 3, 5, 7, 10 kGy의 전자선과 감마선으로 조사하였다. 전자선과 감마선 모두 3 kGy의 조사 시 시험된 미생물을 검출 한계 이하로 사멸시켜 분쇄 육류 원료 사료의 경우 3 kGy의 흡수선량이 충분한 비열 살균 조건임을 보여주었다. 방사선 조사에 의한 원료 사료의 품질 지표 변화를 알아보기 위하여 분쇄 닭고기의 조사 처리 후 pH 변화, 색도 측정, 전자코 이취 분석을 수행하였다. pH와 색도의 경우 감마선 및 전자선 조사에 의해 유의미하게 변화하지 않는 것으로 나타났다. 전자코 이취 시험의 경우 감마선 조사의 경우 3 kGy의 저선량 조사부터 이취가 발생되기 시작하였으며 10 kGy 조사 시 급격하게 이취의 정도가 증가하는 것으로 나타났다. 전자선 조사 역시 3 kGy의 조사부터 이취가 발생하였으며 5 kGy의 선량 이후 흡수선량이 증가함에 따라 이취가 점진적으로 증가하였다. 본 연구 결과 3 kGy의 저선량에서도 닭고기를 원료로한 펫푸드의 비열 살균 효과를 충분하게 이루어짐을 확인하였고 품질 지표에도 부정적인 영향을 주지 않는 것으로 나타났다. 이러한 비열처리 펫푸드의 살균 기술 개발은 국내 펫푸드 시장의 활성화와 반려 동물의 복지 향상에 기여할 것으로 기대된다.