The present study evaluated the repellent activity and the improvements in egg production and mortality rate on laying hens infested with poultry red mites (PRM) administered with a mixture of Korean traditional herbal methanolic extracts (CHE, Foeniculum vulgare : Sophora flavescens : Cinnamomum cassia : Glycyrrhiza glabra = 1:1:1:1, w/w/w/w). PRM numbers per laying hens in CHE-0.5 administered with CHE 0.5 kg/ton feed were significantly decreased compared to those in Non-CHE (control) during overall experimental periods (1st week post-treatment, p<0.05; 2nd week post-treatment, p<0.01; 3rd-4th week post-treatment, p<0.001). In CHE-1.0 administered with CHE 1.0 kg/ton feed, PRM numbers were significantly decreased compared to those in Non-CHE during the whole experimental periods (1st week post-treatment, p<0.01; 2nd-4th week post-treatment, p<0.001). After administration of CHE for 4 weeks, egg production and mortality rate in CHE-0.5 and CHE-1.0 were significantly improved compared to those in Non-CHE (p<0.05). In addition, hematological and blood biochemical parameters in all CHE-treated groups were insignificantly different compared to those in Non-CHE. This study showed that CHE (0.5 and 1.0 kg/ton feed) had a repellent activity on PRM in laying hens and effects on the improvement in egg production and mortality rate of laying hen. CHE could be an effective and safe candidate for the control of PRM and the improvement in egg production and mortality rate of laying hens.

This study was investigated the synergistic antibacterial effects from the combination of sulfamethazine (SMZ) and tiamulin (SMT) against Salmonella Typhimurium (S. Typhimurium) and Actinobacillus pleuropneumoniae (A. pleuropneumoniae) isolated from pigs. Minimum inhibitory concentrations (MICs) and fractional inhibitory concentration (FIC) index were determined for 10 bacteria from 13 swine farms in Gyeongsangnam province by the National Committee for Clinical Laboratory Standards broth microdilution procedure. Antimicrobial agents tested included SMZ, tiamulin and SMT. Against S. Typhimurium and A. pleuropneumoniae, the MIC ranges of SMZ, tiamulin and SMT were 125-500, 15.625-62.5 and 15.625-62.5 μg/mL, respectively. In addition, the FIC index ranges of SMT against S. Typhimurium and A. pleuropneumoniae were 0.19-0.38 and 0.19-0.62, respectively. In conclusion, SMT has a high antibacterial activity against S. Typhimurium and A. pleuropneumoniae, then the combination may be applied for the treatment of swine diseases caused by S. Typhimurium and A. pleuropneumoniae.

Despite the various effects on the health of Chamaecyparis obtusa essential oil (COEO), an adverse effect on the skin has recently been reported. Therefore, in this study, the skin sensitization test of COEO was conducted to confirm the skin safety of the essential oil by the guinea pig maximization test. Guinea pigs were sensitized with intradermal injection of 0.1ml COEO for 24 h. After 1 week, 5% of COEO was treated on the site of injection and 2% of the essential oil was challenged 2 weeks later. The average skin reaction evaluated by erythema and edema on the challenge sites and sensitization rate in the COEO-treatment group at 24 h were 0.0 and 0%, respectively, which are substantially low compared with in the 2,4-dinitrochlorobenzene-treatment group (positive control group) (average skin reaction: 3.0, sensitization rate: 100%) and identical with in the olive oil-treatment group (negative control group), representing a weak sensitizing potential. The average skin reaction and sensitization rate observed at 48 h were 0.0 and 0% in the COEO-treatment group, respectively, and 2.0 and 100% in the positive control group, respectively. It was concluded that 5% of COEO classified to Grade I, induced no sensitization when tested in guinea pigs.

This study was carried out to investigate the acute oral toxicity of Chamaecyparis obtusa (C. obtusa) essential oil (CBE) in New Zealand white male and female rabbits. Acute oral treatment with the CBE did not reveal any sign of toxicity or mortality in treated rabbits. The body weight of the rabbits was not affected after a single oral administration of the CBE during the 14-day observation period. In both the hematological and blood biochemical analysis, all parameters of the treated group with 2,000 mg/kg body weight of the CBE were not significantly different than those of the control group. Therefore, the lethal dose 50 of the CBE was estimated to be greater than 2,000 mg/kg body weight in rabbits, which indicated that the CBE is non-toxic. In conclusion, this study suggests that oral administration of the CBE is safe on rabbits.

This study examined the overdose toxicity of Super-Neophensan, containing florfenicol and acetaminophen, upon pigs. SNP-3.0 (n=10) was administered at the dosage level of 3 kg/ton feed for 7 consecutive days, which is 3 times the recommended dose based on the guidelines of the manufacturer, and the control group (CON) (n=10) was administered the normal diet without the drug. The body weight, weight gain and feed efficiency in SNP-3.0 treated with the drug for 14 days post-administration showed no significant differences compared with those in CON. In hematological and blood biochemical analyses, all parameters were not affected by over-dosage of the drug. In the same way, there were no significant differences between SNP-3.0 and CON on markers for liver and kidney functions. As no adverse effects were observed with the drug in an overdose oral toxicity test, this study suggests that the drug was identified as a safe agent in pigs administered with three times the recommended dose.

A study of the tissue depletion of florfenicol (FFC) administered orally to pigs at a dose of 0.05 kg/ton feed for 7 days was performed. Sixteen healthy cross swine were administered with FFC. Four treated animals were arbitrarily selected to be sacrificed 1, 3 and 5 days after the end of treatment. FFC residue concentrations in muscle, liver, kidney, and fat were determined using high-performance liquid chromatography (HPLC) with ultraviolet photometric detector at 230 nm. The correlation coefficient (R2) of the calibration curve for florfenicol amine (FFCa) was > 0.997 and the limits of detection and quantification were 0.012 and 0.040 μg/mL, respectively. Recovery rates in swine edible tissues ranged from 79.1 to 93.5%. In the FFC-treated group, FFC residues at 3 days post-treatment were below the maximum residue limits (MRLs) in muscle, kidney and fat, and those at 5 days post-administration were below the MRLs in all edible tissues. These results suggest that the withdrawal period of FFC after the drug treatment might be 5 days, which is a sufficient amount of time for reduction of the FFC residues below the MRLs in all edible tissues.

본 연구는 육계에 Hematococcus pluvialis(H. pluvialis)의 급여가 성장 및 혈액 성상에 미치는 효과를 확인하기 위해 수행되었다. 2주령의 육계 120수를 기초사료 급여구(대조구)와 H. pluvialis 건조분말을 0.05(HP 0.05), 0.1(HP 0.1) 및 0.2%(HP 0.2)로 사료에 혼합하여 급여한 3개의 처리구로 나누어 5주 동안 사양시험을 실시하였다. 시험 종료시점에, HP 0.2의 증체량은 대조구와 비교하여 통계적으로 유의성 있게 증가하였으며(p<0.05), 사료요구율도 대조구와 비교하여 통계적으로 유의성 있게 개선되었다(p<0.05). 혈액학적 지표들의 경우, 모든 H. pluvialis 건조분말 처리구와 대조구 사이에 유의적인 차이를 보이지 않았다. 혈액생화학적 지표들의 경우, HP 0.2의 aspartate aminotransferase 값이 대조구와 비교하여 통계적으로 유의성 있게 감소하였다(p<0.05). 본 연구의 결과를 통해, H. pluvialis 건조분말을 사료 톤 당 2.0kg 농도(0.2%)로 육계사료에 첨가하여 급여할 경우에 육계의 성장 및 사료요구율의 개선 효과가 있는 것으로 확인되었다.

This study evaluated the effect of reduced glutathione (GSH) for the reduction of stress and inflammatory response in calves inoculated with foot-and-mouth disease (FMD) vaccine. Twenty-five calves were divided into five groups of 5 calves. The negative control (NC) did not receive any vaccination or drug treatment. The positive control (PC), GSH-25, GSH-50 and GSH-100 were intramuscularly injected with GSH at concentrations of 0, 25, 50 and 100 mg / 10 kg body weight (BW), respectively, for 3 days after FMD vaccination. On day 3, 5 and 7 post-treatment, the serum cortisol and tumor necrosis factor- α (TNF-α) levels in GSH-50 and GSH-100 were significantly decreased compared with those in PC (p < 0.05). However, there was no significant difference in the serum cortisol and TNF-α levels between GSH-100 and NC 3 and 5 days post-treatment, and between GSH-50, GSH-100, and NC 7 days post-treatment. The results from this study suggest that treatment of 50 mg / 10 kg BW GSH for 3 days is useful for the reduction of stress and inflammatory response caused by FMD vaccination in calves.

Highly pathogenic avian influenza virus (HPAIV) damages vital organs and tissues, frequently leading to death in birds, and causes serious economic losses in the poultry industry. In addition, HPAIV can infect humans and other mammals, often with fatal outcomes. In this study, the virucidal efficacy of Clean-Zone®, which contains citric acid, malic acid and phosphoric acid, against avian influenza virus (AIV, H9N2) was investigated. Virucidal efficacy was determined by examining the viability of AIV after contact with the disinfectant in the allantoic membrane of chicken embryos. The disinfectant and AIV were reacted under hard water (HW) and organic matter suspension (OM) condition. AIV was inactivated with 200- and 50-fold dilutions of the disinfectant under HW and OM conditions, respectively. As the disinfectant, Clean-Zone®, has a virucidal efficacy against AIV, it can be used to prevent the spread of animal viral diseases.

본 연구는 우유 중에서 덱사메타손을 효과적으로 정량 분석하기 위한 LC-MS/MS법을 확립하고 이를 검증하기 위해 수행되었다. 확립된 LC-MS/MS에 대해 특이성, 검출 한계, 정량한계, 정확도 및 정밀도에 대한 검증을 통하여 유효성을 확인하였다. 표준용액을 이용하여 검량성을 작성한 결과, r2 > 0.999 이상의 직선성을 확인하였고, 덱사 메타손에 대한 검출한계와 정량한계는 각각 0.15와 0.5 ng/ mL이었다. 또한, 회수율은 98.9-109.6%로 나타났으며, 상대표준편차는 1.7-4.4%로 나타나 정확성이 우수하였으며, 이는 식품의약품안전처의 잔류동물용의약품 분석법에서 제시한 기준에 모두 적합한 수준이었다. 따라서 본 연구를 통해 개발된 LC-MS/MS법은 향후 우유 중 덱사메타손을 분석하는데 효과적으로 활용될 수 있을 것으로 사료된다.

This study examined the acute toxicity of Vital-Shoot containing reduced glutathione in male and female ICR mice. Mice were intraperitoneally injected the drug at dose levels of 0, 250, 500, 1,000 and 2,000 mg/kg body weight (BW) for single-dose toxicity test. There were no statistical differences in BW changes between the control and all treated groups. Based on hematological and blood biochemical analyses, the drug did not affect all parameters. In addition, markers for liver and kidney functions did not meaningfully change in all treated groups. Since there were no adverse effects from the drug in a single-dose intraperitoneal toxicity test, it was concluded that the lethal dose 50 (LD50) of Vital-Shoot is estimated to be >2,000 mg/kg BW.

This study investigated the synergistic effects of a combination of cephalexin and gentamicin (CCG) against Streptococcus spp. isolated from bovine milk. Minimum inhibitory concentrations (MICs) and fractional inhibitory concentration (FIC) index were determined for 12 bacteria isolated from 12 bovine farms in Gyeongnam province. The MIC ranges of cephalexin, gentamicin and CCG were 0.25-0.5, 0.5-2.0 and 0.06-0.125 μg/mL, respectively. In addition, the FIC index range of CCG against the isolates was 0.32-0.34, showing a synergistic effect in the checkboard assay. In conclusion, CCG has a high antibacterial activity against Streptococcus isolates and may be utilized in the treatment of bovine streptococcal mastitis.

살모넬라증은 가축에 심각한 피해를 유발하는 질병으로, 축산업과 식품산업에 많은 경제적 손실을 초래하고 있다. 본 연구에서는, 복합 인산염을 주성분으로 하는 분말 소독제의 Salmonella Typhimuriums에 대한 살균효과 시험을 수행하였다. 배지희석법을 이용한 살균효력시험은 4℃에서 30분 동안 시험 세균을 희석 소독제에 노출시켜 소독제의 가장 효과적인 낮은 희석배수를 결정하는 시험이다. 본 분말 소독제와 시험 세균을 처리조건에 따라 경수와 유기물로 희석하여 반응을 시켰다. 유기물 조건에서, Salmonella Typhimurium에 대한 소독제의 살균력은 경수조건에서의 살균력과 비교하여 낮게 나타났는데, 이는 유기물들에 의한 소독제의 살균 유효성분에 대한 저해작용에 따른 것으로 사료된다. 분말 소독제는 Salmonella Typhimurium과 같은 병원체에 대해 살균효과를 가지므로, 살모넬라증과 같은 세균성 질병의 확산을 제어하는데 효과적으로 이용될 수 있을 것으로 사료된다.

This study investigated the changes in appetite and behavior of cattle and pigs after foot-and-mouth disease (FMD) vaccination. This study involved ten calves and ten pigs, each divided into two groups of five animals. One group of each animal was vaccinated with an FMD vaccine (FMD-V), and the other group was used as a non-treated control (CON). Each animal’s appetite and behavior were observed before vaccination and for seven days post-vaccination. In the FMD-V groups, appetite and behavior scores during the seven days post-vaccination were significantly decreased compared to those in the CON groups. The only exception was the seventh day post-vaccination in the swine behavior scores.

The coronavirus porcine epidemic diarrhea virus (PEDV) infects the cells lining the small intestine of a pig and, causes porcine epidemic diarrhea (PED). Owing to its highly infectious nature, PEDV has a substantial economic burden, which results in significant morbidity and mortality in piglets. In this study, the virucidal efficacy of a powder disinfectant containing a phosphate compound against PEDV was investigated. Virucidal efficacy was assessed as the infectivity of PEDV toward Vero cells after exposure of the virus to the disinfectant. PEDV was exposed to the disinfectant in the presence of either hard water (HW) or an organic matter suspension (OM). In the HW condition, PEDV was inactivated by 4-fold dilution of the disinfectant. In the presence of OM, the disinfectant showed virucidal activity with a 2-fold dilution. As the disinfectant possessed virucidal activity against PEDV, it should be an effective reagent for limiting the spread of animal viral diseases.

살모넬라증과 부루셀라증은 가축 및 사람에 심각한 피해를 유발하는 질병으로, 축산업과 식품산업에 많은 경제적 손실을 초래하고 있다. 본 연구에서는, 자몽종자추출물, 구연산, 사과산 그리고 염화벤잘코늄을 주성분으로 하는 스프레이형 소독제의 Salmonella Typhimurium과 Brucella ovis에 대한 효력시험을 수행하였다. 살균효력시험은 배지희석법에 따라 수행하였으며, 스프레이형 소독제와 시험 세균들을 처리조건에 따라 경수와 유기물로 희석하여 반응을 시켰다. 유기물 조건에서, Salmonella Typhimurium과 Brucella ovis에 대한 스프레이형 소독제의 살균력은 경수조건에서의 살균력과 비교하여 낮게 나타났는데, 이는 유기물들에 의한 소독제의 살균 유효성분에 대한 저해작용에 따른 것으로 사료된다. 스프레이형 소독제는 Salmonella Typhimurium과 Brucella ovis와 같은 인수공통전염병 유발 병원균들에 대해 살균효과를 나타내어, 살모넬라증과 브루셀라증과 같은 세균성 질병의 확산을 제어하는데 효과적으로 이용될 수 있을 것으로 사료된다.

본 연구는 S. Typhimurium을 대상으로 paraformaldehyde 35%를 함유한 훈증소독제의 살균효과를 평가하기 위해 수행되었다. 예비 시험에서, S. Typhimurium의 현탁액 균수는 모두 3.9 × 108CFU/mL이었으며, 훈증소독제에 노출시킨 모든 담체의 균수는 평판배지법과 여과법으로 배양한 시험균주 현탁액의 균수의 50%보다 많았다. 또한, 대조담체로부터 회복된 S. Typhimurium 균수는 모두 3.3 × 106 CFU/mL이었다. 훈증소독제의 살균효과 시험에서는, 훈증소독제를 처리한 담체의 S. Typhimurium의 감소 균수는 5.22 log CFU/mL로 나타났다. 이상의 결과로부터, paraformaldehyde를 주성분으로 하는 훈증소독제는 S. Typhimurium에 대해 효과적인 살균력을 갖는 것으로 확인되었으며, 병원성 세균에 오염된 식품재료 및 주방용품의 소독에 적용할 수 있을 것으로 사료된다.

In this study, the virucidal efficacy of a fumigant (35% paraformaldehyde) against avian influenza virus (AIV) was examined. After AIV suspensions had been deposited on stainless steel carriers, the dried carriers were exposed to the fumigant in a 300-m3 test room for 3 h. Thereafter, all carriers were submerged in a neutralizing solution to scrape off the surviving viruses, and the respective suspensions were diluted. Each dilution factor was respectively inoculated into the allantoic membrane of five 10-day-old embryos. After incubation, AIV viability in the collected allantoic fluids was examined and the EID50 was calculated. The fumigant inactivated ≥5.7log10EID50 of AIV and was nontoxic to the embryos.

Antibiotic Detection Kit (Combination I), a lateral flow immunoassay (LFIA) developed for detecting antibiotic residues in milk, was utilized for the analysis of antibiotic residues in the muscle tissue of olive flounder. After 5-h treatment of samples by placing them in water dosed with sulfadimethoxine (SDM; 200 g/ton water), the residue depletion of SDM was investigated in 25 cultured olive flounders (Paralichthys olivaceus). Muscles from fish were sampled before treatment and on the 1st, 2nd, 3rd, 4th and 5th days after treatment. The concentration of SDM in the muscle was then determined by LFIA. The absorbance ratio of the sample to the control blank (Bs/Bo) was employed as an index to determine the residue in olive flounder muscle. To investigate the recovery rate, standard solutions were added to muscle samples to obtain final concentrations of 25 and 50 ng/mL in the muscle. The recovery rates of all spiked samples were >96.6% of the spiked value. SDM was detectable in the muscle of fish treated with the drug until the 1st day of the withdrawal period. The present study shows that the LFIA can be easily adopted to detect SDM residues in the tissue of farmed fish.

This study investigated the effects of LactoPlanta® (Lactobacillus plantarum (L. plantarum), 2.0 × 109 colony forming units (CFU)/kg) on reduction of noxious gas emission in pig houses as well as improvement of carcass weight and quality in finishing pigs. A total of 850 finishing pigs were assigned to four treatment groups: control (CON, basal diet) (n=190), LP-0.1, 0.1% LactoPlanta® (n=210), LP-0.2, 0.2% LactoPlanta® (n=230), and LP-0.4, 0.4% LactoPlanta® (n=220). Ammonia and hydrogen sulfide concentrations were significantly reduced in all treatment groups compared to CON. Mercaptan contents and carcass weights of LP-0.2 and LP-0.4 were significantly decreased compared to CON, whereas there were no significant differences between LP-0.1 and CON. Carcass weight of LP-0.1 was slightly higher than that of CON, but there was no significant difference. However, carcass weights of LP-0.2 and LP-0.4 were significantly higher than that of CON (P<0.05). The prevalence of grade A carcasses in groups administered with L. plantarum (46.7~63.3%) was higher than that in CON (43.3%) and increased in a dose-dependent manner. Based on the results of this study, L. plantarum could be an effective candidate to reduce noxious gas emissions in finishing pig houses as well as improve carcass weight and quality in finishing pigs.