• Journal of Microbiology
• /
• 제44권3호
• /
• pp.344-353
• /
• 2006

Symptoms of fowl cholera including orofacial edema, swollen and edematous wattles and combs, and severe respiratory disorders were detected in domestic poultry in two broiler breeder farms: one located in Gyeong-gi Province (October, 2000) and the other in Chung-cheong-nam Province (March, 2001). Gram-negative, bipolar staining bacillus was easily found in a direct smear. The biochemical properties of isolates were examined using a standard diagnosis method, proving that they were 99.7% similar to the Pasteurella multocida (P. multocida: PM), a pathogenic and causative agent of fowl cholera (FC). As a result, an FC outbreak in domestic fowls was confirmed for the first time in Korea since 1942. Because FC was detected in broiler breeder farms for the first time in 59 years at the same time as an FC outbreak was confirmed in wild birds (October, 2000), our concern was focused on whether the PM strains that originated in wild birds were transmitted into poultry forms. The possibility was tracked down by comparing phenotypic and genetic properties between the two types of PM strains. PM strains of chicken origin showed prominent differences from the PM strains of wild bird origin in both phenotypic and genetic properties. An examination of the origin of the wild bird bacteria was conducted, but no evidence has been identified that PM strains from the wild bird were introduced into domestic poultry farms.

• 한국동물위생학회지
• /
• 제35권2호
• /
• pp.91-97
• /
• 2012

The strategy for infectious bursal disease (IBD) control and its success rate under field conditions depends on hygiene management, IBD field pressure, level, and variation in maternally derived IBD antibodies. This study investigated the level of IBD-specific antibody by ELISA and the prevalence of IBD virus by PCR in broilers, white-semi broilers, and Korean native chickens raised in Jeongeup, Jeonbuk. IBD-specific maternally derived antibodies were measured from 698 chickens and the mean titers of maternal antibodies were $3,572{\pm}1,402$ in broilers, $1,262{\pm}762$ in white-semi broilers, and $1,932{\pm}912$ in Korean native chickens. At 2 weeks after vaccination, the geometric mean antibody titers of broiler, white-semi broiler, and Korean native chicken were $582{\pm}427$, $3255{\pm}1,080$, and $1,023{\pm}499$, respectively. According to sequence analysis of the variable virion protein 2 gene, 4 isolates were found to be very virulent IBDV, 9 isolates classical virulent, and 2 isolates intermediate plus vaccine strain.

• Journal of Animal Science and Technology
• /
• 제65권3호
• /
• pp.490-510
• /
• 2023

Feed safety is needed to produce and provide safe animal feeds for consumers, animals, and the environment. Although feed safety regulations have been set for each country, there is a lack of clear feed safety regulations for each livestock. Feed safety regulations are mainly focused on heavy metals, mycotoxins, and pesticides. Each country has different safe levels of hazardous materials in diets. Safe levels of hazardous materials in diets are mostly set for mixed diets of general livestock. Although there is a difference in the metabolism of toxic materials among animals, the safe level of feed is not specific for individual animals. Therefore, standardized animal testing methods and toxicity studies for each animal are needed to determine the correct safe and toxic levels of hazardous materials in diets. If this goal is achieved, it will be possible to improve livestock productivity, health, and product safety by establishing appropriate feed safety regulations. It will also provide an opportunity to secure consumer confidence in feed and livestock products. Therefore, it is necessary to establish a scientific feed safety evaluation system suitable for each country's environment. The chance of outbreaks of new hazardous materials is increasing. Thus, to set up appropriate toxic levels or safe levels in feed, various toxicity methods have been used to determine toxic levels of hazardous materials for humans and animals. Appropriate toxic testing methods should be developed and used to accurately set up and identify toxicity and safe levels in food and feed.

• Journal of Animal Science and Technology
• /
• 제66권1호
• /
• pp.232-236
• /
• 2024

Ligilactobacillus is a genus of Gram-positive lactobacilli commonly found in the intestinal tracts of vertebrates. It has been granted a Qualified Presumption of Safety (QPS) status from the European Food Safety Authority (EFSA). One specific strain, Ligilactobacillus salivarius B4311, was isolated from fecal samples of broiler chickens from a farm associated with Chung-Ang University (Anseong, Korea). This strain was observed to have inhibitory effects against Listeria monocytogenes. In this paper, we present the complete genome sequence of Lig. salivarius B4311. The whole genome of strain B4311 comprises 2,071,255 bp assembled into 3 contigs representing a chromosome, repA-type megaplasmid, and small plasmid. The genome contains 1,963 protein-coding sequences, 22 rRNA genes, and 78 tRNA genes, with a guanine + cytosine (GC) content of 33.1%. The megaplasmid of strain B4311 was found to contain the bacteriocin gene cluster for salivaricin P, a two-peptide bacteriocin belonging to class IIb.

• 한국가금학회지
• /
• 제10권2호
• /
• pp.113-121
• /
• 1983

국내에서 발생하고 있는 ILT의 역학적인 사항을 파악하기 위하여 1982년 6월부터 1983년 8월까지 ILT가 발생된 5개 종계농장과 1개 산란계농장의 총56개 계군을 대상으로 계군간 및 계군내 전파속도와 전파수단, 품종, 나이, 사양형태에 따른 감수성의 차이, 발병 전후의 백신접종이 피해를 줄이는데 미치는 영향 등을 조사하였다. 6개 대상농장 중 5개 농장에서는 ILT발생 직전 또는 직후 백신접종을 실시하였으며 겨울철에 발생한 2개 농장에서는 발생직후 철저한 전파수단의 차단에 의해서 농장별로 1-2계군의 발생에 그치고 나머지 5-7계군은 발생이 없었다. 계군간의 전파속도는 평사계군이 평균 6일로서 케이지계군(11.5일)보다 빨랐으나 유의적인 차이는 인정할 수 없었다. 한편 케이지계군 중 산란을 하지 않는 미성숙계군간의 전파기간이 17일인데 반하여 산란중인 계군에서는 8일로서 유의적인 차이가 인정되어 난좌나 집란과정에 의한 전파촉진 가능성을 엿볼 수 있었다. 발병계군 내에서의 폐사기간은 평균 18일로서 사육형태. 품종 및 나이에 따른 차이를 인정할 수 없었다. 또한 폐사율은 평균 6.5%로서 미성숙육계종계군(2.9%)이 미성숙산란계군(11.8%)이나 산란중인 육계종계군(6.9%)에 비하여 월등히 낮았을 뿐 다른 어떤 기준에서도 궤사율의 차이를 인정할 수 없었다. 조사대상 농장 중 여름철에 발생한 한 육계종계 농장에서는 계군의 나이에 따라 37주령 이상된 7개 계군에서는 모두 수탉이 암탉에 비하여 두배 이상의 높은 폐사율을 보여 주었다.

• 한국가금학회지
• /
• 제37권3호
• /
• pp.221-228
• /
• 2010

본 시험은 육계에 마늘 부산물을 급여하여 5주간 사육한 육계의 생산성과 계육의 일반 성분, pH, 도체 특성, 콜레스테롤 함량 및 혈액 조성을 조사하였다. 실험구는 마늘 부산물을 첨가 급여하지 않은 처리구를 대조구, 마늘 부산물 1% 급여구는 T1, 마늘 부산물 2% 급여구는 T2 그리고 마늘 부산물 5% 급여구는 T3 등 4개 처리구로 나누어 사양하였다. 육계의 증체량, 사료 섭취량, 사료 요구율 등의 생산성은 유의적인 변화가 없었다. 계육의 일반 성분 중 조지방은 마늘 부산물을 급여함에 따라 감소하였고(P<0.05), T2에서 가장 낮은 함량을 보이고 있으며, 수분과 조회분은 처리구간에 유의성은 없었다. 도체 특성 중 간의 무게는 마늘 부산물 급여구에서 무거웠으며, 급여량이 증가할수록 다소 무거운 경향이었다(P<0.05). 계육의 총 콜레스테롤과 LDL-cholesterol은 마늘 부산물 급여구에서 낮았고, 특히 T3에서 가장 낮았으며 HDL-cholesterol은 높아지는 결과이었다(P<0.05). 혈액 성분중GOT는 마늘 부산물을 급여함으로 감소하는 경향이었고, GPT, triglyceride, glucose는 유의성이 없었다. 결론적으로 마늘 부산물 2%를 급여하면 육계의 생산성에는 영향을 미치지 않으면서 계육의 콜레스테롤 함량에 영향을 미칠 수 있을 것으로 사료된다.

• 한국가금학회지
• /
• 제32권2호
• /
• pp.101-106
• /
• 2005

산란노계를 닭고기로서 자원화하여 농가의 수익과 단백질 공급원으로 활용하기 위한 목적으로, 생산성이 낮고 경제적 가치가 적은 산란노계 사료에 목초액을 첨가${\cdot}$급여하여 육질 개선 효과를 조사하기 위하여 계획하였다. 이사브라운 갈색종 240수를 배치하여 대조구에는 육계용 배합사료, 시험 1구에는 국산 목초액 $0.8\%$, 시험 2구에는 외국산 목초액 $0.4\%$를 첨가하여 급여하였다. 사료 섭취량은 대조구가 시험구보다 3g 정도 적었는데 목초액의 유기산이 사료의 소화에 영향을 준 것으로 사려된다. 사육성적의 차이는 국산과 외국산 목초액의 구성성분의 차이에 기인하며, 외국산 목초액의 첨가는 성페르몬과 성분이 유사한 목초액이 내분비 물질의 분비를 촉진한 결과 산란율이 증가하였고, 목초액의 첨가에 따라 조지방 함유량은 다리 고기가 가슴고기보다 많았으며 육색의 개선 효과도 있었다. 다리고기의 육질과 관능검사는 근섬유의 조직을 가늘게 하고 보습력을 증가시키는 외국산 목초액 첨가구에서 좋은 평가를 받았다.

• 한국가금학회지
• /
• 제9권2호
• /
• pp.63-101
• /
• 1982

육용계에서 가식육량을 효과적으로 추정할 수 있는 방법을 구명코자 White Cornish종과 S. C. W. Leghorn종. 그리고 이 두 품종의 상반교잡종을 각각 120수씩 계 480수를 공시하여 체중. 부위별 가식육 및 체형의 변화, 이들 형질에 발현된 잡종강세와 반성유전효과 및 화학적 조성분함량을 조사하고. 성장단계별 가식육량을 추정한 결과를 요약하면 다음과 같다. 1. W. Cornish종의 8주시 체중 및 사료요구율과 폐사율을 보면 각각 1,818.8$\pm$47.7g와 2.24 및 3.30%였고 S. C. W. Leghorn종에선 각각 667.8$\pm$28.9g와 3.28 및 2.50%였으며 잡종들의 능력은 이 두 품종의 중간정도로 정상발육을 하였다. 2. 체중에 있어서 계종간 차이는 2주령부터 유의성이 인정되었고. 성장곡선의 회귀방정식에서 성장속도를 표시하는 회귀계수률 보면 W. Cornish종( $b_{cc}$ =1,578)은 S. C. W. Leghorn종 ( $b_{LL}$ =1,378)에 비해 유의적으로 크고 교잡종들은 이 두 품종의 중간값( $b_{LC}$ =1,476, $b_{CL}$ =1,470)을 보인다. 가식육량의 경우도 계종간 증가양상이 체중의 경우와 비슷하였으나 육량증가의 회귀방정식에서 회귀계수의 크기가( $b_{LL}$ =1,563, $b_{LC}$ =1,651, b.$_{CL}$ =1,636, $b_{CC}$ =1,766) 체중에서 보다 컷는데 그 원인이 성장속도 차이때문인지를 구명하기 위해 주령(log x)과 체중에 대한 가식육량비율(log y) 간의 선형관계를 추정한 결과 각 계종의 회귀계수( $b_{LL=0.184}$, $b_{LC}$ =0.175, $b_{CL=0.165}$ 및 $b_{CC}$ =0.188)는 모두유의성이 인정되어 가식육의 증가속도는 체중의 증가속도보다 현저히 빠른 것으로 판명되었다. 3. 체중구성요소중 주령경과에 따라 그 중량비율이 증가되는 것은 우모, 복강지방, 흉부 및 퇴경부이고, 감소되는 것은 두부, 경부, 가식내장 및 부가식내장이며 방혈량, 각부, 익부 및 배부는 큰 변화를 보이지 않는다.

• Journal of Animal Science and Technology
• /
• 제62권2호
• /
• pp.159-173
• /
• 2020

A 4×2 factorial feeding trial was designed to investigate the effect of replacing soybean meal (SBM) with cottonseed meal (CSM) in wheat/sorghum/SBM-based diets fed with or without microbial enzymes in diets on the performance, visceral organ development and digestibility of nutrients of broiler chickens. Four graded levels of CSM - none (0%), low (4%, 8%, and 12%), medium (5%, 10%, and 15%), and high (6%, 12%, and 18%) of complete diets in starter, grower and finisher, respectively were fed with or without 100 mg/kg of xylanase and β-glucanase blend. Eight isocaloric and isonitrogenous diets were formulated using least-cost method to meet the nutrient specifications of Ross 308 male broilers. Each treatment was randomly assigned to 6 replicates (10 birds per replicate). There were CSM-enzyme interactions (p < 0.05) on feed intake (FI) and weight gain (WG) in the starter phase. Enzyme supplementation improved (p < 0.05) feed conversion ratio (FCR) in the grower and finisher phases, and increased WG in growing and finishing birds. CSM inclusion reduced (p < 0.05) the weight of gizzard and proventriculus in starter chicks, while these organs were bigger (p < 0.05) in the grower phase. The test ingredient decreased (p < 0.05) small intestinal weight in starter and grower birds. The CSM increased the absolute weight of thighs (p < 0.05) while breast meat was increased (p < 0.01) by enzyme addition. Starch digestibility was improved (p < 0.01) by enzyme inclusion and decreased (p < 0.01) by CSM. Enzyme supplementation improved (p < 0.05) the ileal digestibility of gross energy and protein. The results demonstrate that CSM can substitute up to 90% SBM in broiler chicken diets without compromising performance, and the nutritive value of CSM-containing diets can effectively be improved by enzyme supplementation.

• Animal Bioscience
• /
• 제35권8호
• /
• pp.1223-1234
• /
• 2022

Objective: The objectives of this study were to evaluate the effects of daily feed intake during the laying period on embryonic myogenic differentiation 1 (MYOD1), myogenic factor 5 (MYF5), and myogenic factor 6 (MYF6) gene expression in genetically fat and lean lines of chickens. Methods: An experiment in a 2×2 factorial design was conducted with two dietary intake levels (100% and 75% of nutrition recommendation) and two broiler chicken lines (fat and lean). Two lines of hens (n = 384 for each line) at 23th week of age were randomly divided into 4 treatments with 12 replicates of 16 birds. The experiment started at 27th week of age (5% egg rate) and ended at 54th week of age. Hatched eggs from the medium laying period were collected. Real time polymerase chain reaction analysis was used to analyse the MYOD1, MYF5, and MYF6 mRNA levels of E7, E9, E11, E13, and E15 body tissues and E17, E19, and E21 chest and thigh muscle samples. Results: The results indicated that there were significant effects of line, dietary intake, and interactions between them on MYOD1, MYF5, and MYF6 gene mRNA expression levels in embryonic tissues. Low daily feed intake did not change the expression trend of MYOD1 mRNA in either line, but changed the peak values, especially in lean line. Low daily feed intake altered the trend in MYF5 mRNA expression level in both lines and apparently delayed its onset. There was no apparent effect of low daily feed intake on the trends of MYF6 mRNA expression levels in either line, but it significantly changed the values on many embryonic days. Conclusion: Maternal nutrient restriction affects myogenesis and is manifested in the expression of embryonic MYOD1, MYF5, and MYF6 genes. Long term selection for fat deposition in broiler chickens changes the pattern and intensity of myogenesis.