This study evaluated the efficacy of a wild boar repellent (Repellent A) consisting of tannins and plant oils (castor oil, garlic oil, and cinnamon oil). Sixty farmed wild boars (4-8 months old) were divided into three groups: the normal control group (NC, n=20), the experimental group (EP, n=20), and the comparative experimental group (C-EP, n=20), which used Repellent B consisting of guaiacol, eugenol, menthol, thymol, and indole. EP and C-EP were equipped with four repellents per feeder, while no repellents were installed in the NC feeder. The feed intake and the number of feeding approaches were measured for one week in all groups. The number of approach of wild boars in feeders was monitored daily using a CCTV camera. The daily feed intake per farmed wild boar in EP and C-EP was significantly decreased compared to NC (p<0.05), and EP was significantly decreased compared to C-EP (p<0.05). In the average number of daily approaches, EP and C-EP were significantly decreased compared to NC (p<0.05), and EP was significantly decreased compared to C-EP (p<0.05). In conclusion, Product A has been confirmed to have excellent repellent effects on wild boars, and it could be used to prevent wild boars from approaching pig farms.
This study evaluated the immunogenicity of the Bacillus Calmette-Guérin (BCG) vaccine in a guinea pig model to refine preclinical assessment methods. 24 guinea pigs were divided into four groups for immunohistochemical, histopathological, and molecular analyses, including qRT-PCR and ELISA. The ELISA results revealed significant elevations in interleukin 2 (IL-2), interferon-gamma (IFN- ), and tuberculosis-specific antibodies in vaccinated guinea pigs, particularly γ notable after 6 weeks. Although lung cytokine levels remained unchanged, spleen gene expression showed significant differences in interleukin-17, interleukin-12, interleukin-1β, and C-X-C motif chemokine ligand 10 after 6 weeks. Immunohistochemistry revealed peak IL-2 expression at 8 weeks and significant IFN-γ and TNF-α expression at 6 weeks. This study confirmed the effectiveness of BCG vaccine in guinea pigs, providing crucial insights for future tuberculosis vaccine development and standardizing immune response indicators.
The present study, black soldier flies (Hermetia illucens) fermented using lactic acid bacteria were powdered without defatting and added to 3% or 5% to make pig feed. Weaning piglets were fed 3% (T3) or 5% (T5) feed powdered with Hermetia illucens for 5 months and the efficacy of the feed was investigated. The results of measuring body weight gain over 5 months after adding 3% (T3) or 5% (T5) of Hermetia illucens powder to the feed of weaned piglets showed significant weight gain in the T5 group compared to the control group. The added feed to Hermetia illucens powder did not show toxicity, and analysis of its effect on blood properties showed that white blood cell levels tended to increase in the T3 or T5 group compared to the control group.The only increase in white blood cell count was a change within the normal range. As a result of analyzing the effect of the level of addition of Hermetia illucens powder on feces, the effect of liquid reduction showed excellent results in the T3 treatment group and maintained the best form of feces. In this study, the thawing loss in the control group was 6.66%, and the T3 group with added powder to Hermetia illucens showed a significant decrease of 5.03%, and the T5 group also showed a decrease of 5.61%. Therefore, it was demonstrated that additive feed for Hermetia illucens reduced thawing loss, affected the water holding capacity of meat, and played an important role in maintaining the taste of meat. Moreover, the results of carcass grade showed a tendency for one grade to increase in the T3 and T5 groups fed additive feed to Hermetia illucens compared to the control group. In conclusion, the results of this study suggest that feed supplemented with Hermetia illucens is effective in influencing the weight gain of pigs, reducing the liquid content of feces, and increasing carcass grade.
From 2020, Korean Animal and Plant Quarantine Agency has reset the withdrawal time (WT) for veterinary drugs typically used in livestock in preparation for the introduction of positive list system (PLS) program in 2024. This study was conducted to reset the MRL for tiamulin (TML) in broiler chickens as a part of PLS program introduction. Forty-eight healthy Ross broiler chickens were orally administered with TML at the concentration of 25 g/L (TML-1, n=24) and 50 g/L (TML-2, n=24) for 5 days through drinking water, respectively. After the drug treatment, tissue samples were collected from six broiler chickens at 1, 2, 3 and 5 days, respectively. According to the previously established analysis method, residual TML concentrations in poultry tissues were determined using LC-MS/MS. In TML-1, TML in all tissues was detected less than LOQ at 2 days after drug treatment. In TML-2, TML in liver and kidney was detected more than LOQ at 2 days after treatment. According to the European Medicines Agency’s guideline on determination of withdrawal periods, withdrawal periods of TML-1 and TML-2 in poultry tissues were established to 0 and 2 days, respectively. In conclusion, the estimated WT of TML in poultry tissues is shorter than the current WT recommendation of 5 days for TML in broiler chickens.
This study evaluated the virucidal efficacy of a chlorine dioxide (ClO2) gas-generating fumigation disinfectant consisting of sodium chlorate solution (25% sodium chlorate) and reaction solution against avian influenza virus (AIV). After AIV suspensions had been deposited on stainless steel carriers, the 9 dried carriers were exposed to the fumigant (sodium chlorate solution: 8.5, 17, 34, 50, and 100 mL) in a 25-m³ test room for 2, 3, and 4 h, respectively. Thereafter, all carriers were submerged in a neutralizing solution (20% fetal bovine serum) to scrape off the surviving viruses, and the respective suspensions were diluted. Each diluent was inoculated into the allantoic membrane of five 10-day-old embryos. After incubation for 5 days at 37℃, AIV viability in the collected allantoic fluids was examined, and the egg infectious dose 50 (EID50) was calculated. When the carrier was exposed to ClO2 gas generated from reacting 34 mL of the fumigant for 3 h, the AIV titer reduced by more than 104.0 EID50/carrier compared to the control, which was exposed to the fumigant without inoculation of AIV suspension. In addition, the control was non-toxic to the embryos.
This study was conducted to reset the maximum residue limit (MRL) for didecyldimethylammonium chloride (DDAC) in broiler chickens. The disinfectant containing DDAC (10%, w/w) was diluted 160 times and evenly sprayed on the bodies of twenty-four broiler chickens at a rate of 15 mL per day per bird for 7 days. After the disinfectant treatment, tissue samples were collected from six broiler chickens at 0.25, 1, 3 and 5 days, respectively. Residual DDAC concentrations in poultry tissues were determined using LC-MS/MS. Correlation coefficient (0.99 >), the limits quantification (LOQ, 2.0~10.0 μg/kg), recoveries (86.9~118.6%), and coefficient of variations (<19.98%) were satisfied the validation criteria of Korean Ministry of Food and Drug Safety. In all tissues except for liver, DDAC was detected more than LOQ at 5 days after the disinfectant treatment. In liver tissues, DDAC was detected more than LOQ at 3 days after treatment. According to the European Medicines Agency’s guideline on determination of withdrawal periods, withdrawal period of DDAC in poultry tissues was established to 26 days. In conclusion, the developed analytical method is sensitive and reliable for detecting DDAC in poultry tissues. When DDAC disinfectant is sprayed on a poultry house in the presence of broiler chickens, it is necessary to keep the disinfectant from contacting the body of the livestock.
This study evaluated the fungicidal efficacy of weakly acidic hypochlorous acid water (WAHW) against Microsporum canis (M. canis) and its therapeutic effect on M. canis-infected mouse skin. WAHW was produced by a WAHW generation module. A fungicidal efficacy test by the broth dilution method was used to determine the lowest effective concentration of the WAHW. The lowest effective concentration of WAHW was less than 10 ppm. For T-1, T-2, and T-3, 30 ppm of WAHW was applied to the infected skin once, twice, and three times a day, respectively, and for T-4, 50 ppm of WAHW was applied once a day. On the 3rd day after the initiation of treatment, skin scores in all of the WAHW-treated groups were significantly decreased compared to those in the positive control group (PC) (p<0.05), and there were no significant differences compared to the normal control (NC). The area of the infected skin in all of the WAHW-treated groups was significantly decreased compared to PC from the first day after the initiation of WAHW treatment (p<0.05). The results showed that WAHW had a fungicidal efficacy on M. canis at less than 10 ppm, and it was effective in improving skin symptoms when 30 ppm of WAHW was applied to the M. canis-infected area once a day for five days or 50 ppm of WAHW was applied once a day.
This study investigated ethopabate (EPB) residues in edible tissues of broiler chickens given in drinking water and established the withdrawal time (WT) of EPB in poultry tissues. Twenty-four healthy Ross broiler chickens were orally administered with EPB at the concentration of 3.8 mg/L for 14 days (EPB-1, n=24) and 15.2 mg/L for 7 days (EPB-2, n=24) through drinking water, respectively. After the drug treatment, tissue samples were collected from six broiler chickens at 0, 1, 3, and 5 days, respectively. EPB residue concentrations in poultry tissues were determined using LC-MS/MS. Correlation coefficient values ranged from 0.9980 to 0.9998, and the limits of detection and quantification (LOQ) were 0.03~0.09 and 0.1~0.3 μg/kg, respectively. Mean recoveries in muscle, liver, kidney and skin/fat tissues were 95.9~109.8, 108.7~115.3, 89.9~96.6 and 86.7~96.8%, respectively, and coefficient of variations were less than 17.11%. At the end of the drug-administration period (0 day), EPB was detected at levels under the LOQ in all tissues from both the EPB-1 and EPB-2 groups. According to the results of EPB residue in Ross broiler tissues, withdrawal periods of both EPB-1 and EPB-2 in poultry tissues were established to 0 day. In conclusion, the developed analytical method is suitable for the detection of EPB in poultry tissues, and the estimated WT of EPB in poultry tissues will contribute to ensuring the safety of Ross broiler chickens.
From 2020, Korean Animal and Plant Quarantine Agency has reset the withdrawal time (WT) for veterinary drugs typically used in livestock in preparation for the introduction of positive list system (PLS) program in 2024. This study was conducted to reset the MRL for amprolium (APL) in broiler chickens as a part of PLS program introduction. Forty-eight healthy Ross broiler chickens were orally administered with APL at the concentration of 60 mg/L (APL-1, n=24) for 14 days and 240 mg/L (APL-2, n=24) for 7 days through drinking water, respectively. After the drug treatment, tissue samples were collected from six broiler chickens at 0, 1, 3 and 5 days, respectively. Residual APL concentrations in poultry tissues were determined using LC-MS/MS. Correlation coefficient (0.99 >), the limits quantification (LOQ, 0.3~5.0 μg/kg), recoveries (81.5~112.4%), and coefficient of variations (<15.5%) were satisfied the validation criteria of Korean Ministry of Food and Drug Safety. In APL-1, APL in all tissues except for kidney was detected less than LOQ at 3 days after drug treatment. In APL-2, APL in liver and kidney was detected more than LOQ at 5 days after treatment. According to the European Medicines Agency’s guideline on determination of withdrawal periods, withdrawal periods of APL-1 and APL-2 in poultry tissues were established to 3 and 2 days, respectively. In conclusion, the developed analytical method is sensitive and reliable for detecting APL in poultry tissues. The estimated WT of APL in poultry tissues is longer than the current WT recommendation of 2 days for APL in broiler chickens.
This study examined the subacute oral toxicity of Dendropanax morbiferus H.Lév leaves hot-water extracts (DMWE) using male and female Spargue-Dawley rats. Rats were orally administered the DMWE at dose levels of 0, 250, 500, 1,000, and 2,000 mg/kg body weight (BW) for four weeks. For experimental period, clinical signs and the number of deaths were examined, and feed intake and BW of all experimental animals were measured once a week for four weeks. At the end of the experiment, blood samples were collected from all rats, and all animals were euthanized and autopsies were performed to collect major organs. No dead animals were found during the experimental period. In addition, no differences were found between control and DMWE-treated groups in feed intakes, BW changes, organ weights, clinical signs, hematological parameters, and serum biochemical parameters. The results of this study provided evidence that oral administration of DMWE at the dose of 2,000 mg/kg BW is safe in rats and may not exert severe toxic effects.
In this study, the acute toxicity of Dendropanax morbiferus H.Lév leaf hot-water extracts (DMWE) was examined in male and female ICR mice. Mice were orally administered the DMWE 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 significant differences in change of BW between control and all DMWE treated-groups. In hematological and blood biochemical analysis, none of the parameters were affected by the DMWE. Similarly, there were no significant effects on markers for liver and kidney functions in all DMWE treated-groups. Since there were no adverse effects of the DMWE in single oral toxicity tests, even at the highest doses, it was concluded that the lethal dose 50 (LD50) of DMWE is estimated at > 2,000 mg/kg BW.
This study evaluated the effect of a combination of acetaminophen (AAP), vitamin C (VC) and thioctic acid (TA) on reducing serum cortisol concentrations in mice with foot-and-mouth disease (FMD) vaccination. For 5 days from 3 days before FMD vaccination to 2 days after vaccination, mice were orally administered with AAP 600 mg/kg feed (n=25, AAPT), combination of AAP 600 mg and VC 200 mg per kg feed (n=25, AVCT) and combination of AAP 600 mg, VC 200 mg and TA 20 mg per kg feed (n=25, AVTT), respectively. From day 1 to day 7 after FMD vaccination, the cortisol concentration of all groups treated with the drug was significantly decreased compared to that of the positive control group with FMD vaccination (p<0.05). In conclusion, the combined treatment of AAP, VC and TA was the most effective in relieving stress from FMD vaccination compared to the single treatment.
This study investigated changes of milk production in dairy cows intramuscularly injected with drugs containing dexamethasone (DXM). Three types of dexamethasone formulations (Bueunde® (DXM 0.5 mg/mL), Dexason INJ.® (DXM 1 mg/mL) and Dexolone-20 inj.® (DXM 1 mg/mL)) were intramuscularly injected into sixteen healthy dairy cows each. Bueunde® was intramuscularly injected into 8 dairy cows with 5 mg (BED-1) and 10 mg (BED-2) of DXM once a day for 3 consecutive days, respectively. Dexason INJ.® was intramuscularly administered once into dairy cows with 20 mg (DXS-1, n=8) and 40 mg (DXS-2, n=8) of DXM, respectively. Dexolone-20 inj.® was intramuscularly injected once into dairy cows with 20 mg (DXS-1, n=8) and 40 mg (DXS-2, n=8) of DXM, respectively. Milk production (MP) of BED-1 and BED-2 significantly decreased during the drug administration and up to 48-hour post-drug treatment. Compared with the MP before drug administration, the MP of DXS-1 and DXL-1 was meaningfully decreased by 36 and 24-hour post-drug administration, respectively, and that in both DXS-2 and DXL-2 significantly decreased until 48-hour post-drug treatment. In conclusion, it was confirmed that the MP temporarily decreased by 48 hours after administration of DXM to dairy cows.
Based on many previous studies, this study reviewed the effects of needle-free intradermal injection (NFI) on the prevention of the incidence of lesions at the injection site in pork from pigs vaccinated with the foot-and-mouth disease vaccine, the reduction of the vaccine dose, the stress-relief of vaccination, and the reduction of farm worker-related injuries. The vaccine and drugs injected with the NFI pass through the tissue and are widely dispersed along the path of least resistance, resulting in a vastly dispersed, spider-web-like distribution of the medication and absorbed quickly. In addition, since NFI is inoculated into the dermal layer where immune cells are abundantly distributed, even a small amount of vaccination shows an antibody-forming effect similar to that of the conventional needle intramuscular injection. NFI is a method suitable for animal welfare because the vaccine or drug is widely dispersed over the inoculation site and causes less pain or stress than the needle intramuscular injection. Use of NFI system for the vaccination and drug delivery improves work efficiency in farms and reduces the incidence of musculoskeletal disorders in farm workers. In the future, it is judged that in-depth studies are needed on the effect of improving productivity and reducing the dose of antibiotics through NFI.
This study investigated chlorpheniramine maleate (CPM) residues in milk of intramuscularly dosed dairy cows and established the withdrawal time (WT) of CPM in milk. Sixteen healthy Holstein cows were injected with 10 (CPM-1) and 20 mL (CPM-2) of the drug containing 4 mg/mL of CPM, respectively. After administration of CPM, milk samples were collected from all cows at 12 hour intervals for 5 days. CPM residue concentrations in milk were determined using LC-MS/MS. The correlation coefficient of the calibration curve was 0.9956, and the limits of detection and quantification (LOQ) were 0.6 and 1.0 μg/kg, respectively. Recoveries ranged between 98.5-115.0%, and coefficient of variations were less than 10.96%. After treatment, CPM in CPM-1 and CPM-2 was detected below the LOQ in all milk samples at 12 hours. According to the European Medicines Agency’s guideline on determination of withdrawal periods for milk, withdrawal periods of both CPM-1 and CPM-2 in milk were established to 12 hours. In conclusion, the developed analytical method is sensitive and reliable for detection of CPM in milk, and the estimated WT of CPM in bovine milk will contribute to ensuring the safety of milk.
A number of studies have been conducted to confirm the preventive effect of xylitol on dental caries as a whole or partial alternative to dietary sugars. This study reviewed the oral health effects of xylitol on the prevention mechanism of dental caries, the prevention of dental caries, the inhibition of mother-to-child transmission, and the oral health effects in the elderly based on existing studies on the oral health of xylitol. Carbohydrates and dietary sugars in food are fermented by acid-producing microorganisms in the mouth and produce dental plaque and acid, which cause dental caries. However, most dental decay-causing bacteria cannot produce acids by metabolizing xylitol. Xylitol, stored in cells as a non-metabolizable metabolite by Streptococcus mutans (S. mutans), affects bacterial glucose metabolism and inhibits bacterial growth. Xylitol consumption also reduces the amount of plaque and the population of S. mutans in both plaque and saliva. In addition, xylitol acts in the remineralization process. Xylitol has been confirmed to effectively prevent dental caries, inhibit mother-to-child transmission of MS, prevent dental caries, and increase salivary flow in the elderly. In conclusion, xylitol is an adequate sugar substitute for dental health, from infants to the elderly. For future studies, the researchers recommend reviewing the effects of xylitol on the oral and intestinal microbial environment and the side effects of excessive intake.
The present study is designed to investigate the antibacterial effect of the hot-water and various ethanol extracts from the leaves of Dendropanax morbifera L. (DML) against Porphyromonas gingivalis (P. gingivalsis). Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of 30, 50 and 70% ethanol extract of DML against P. gingivalis decreased in a concentration-dependent manner. However, MIC and MBC of hot-water and 30% ethanol extract against P. gingivalis were the same as 3.13 and 6.25 mg/mL, respectively. In the bacterial growth inhibition test, the growth of P. gingivalis in the group treated with MBC and 2×MBC of DML hot-water extract was statistically significantly decreased from 6 h after incubation compared to the control group (p<0.001). From the results portrayed above, aqueous extract from DML at the concentration of 6.25 mg/mL can be usefully used to suppress infection of P. gingivalis, a major causative agent of periodontal disease.
This study compared the immune responses, stress relief and weight gains of needle or needle-free intramuscular and needle-free intradermal vaccination in pigs. When the same amount of a foot-and-mouth disease (FMD) vaccine was administered to pigs, antibody titers at 4 weeks after the 1st and 2nd FMD vaccination were not significantly different between the needle (IM-S) and needle-free (NM-P250) intramuscularly vaccinated groups, but the weight gain of NM-P250 was significantly increased compared to that of IM-S at 8 weeks after the 2nd FMD vaccination (p<0.05). In addition, serum cortisol concentrations of NM-P250 were considerably decreased compared to those of IM-S on the 5th and 7th day after the 1st and 2nd FMD vaccination (p<0.05). However, the antibody titers of IM-S vaccinated with 2 mL of FMD vaccine were significantly increased compared to those of the needle-free intradermal vaccinated group with 0.5 mL of FMD vaccine at 4 weeks after the 1st and 2nd FMD vaccination (p<0.05). In conclusion, the needle-free intramuscular injection for the FMD vaccination can be chosen for weight gain and stress relief in pigs.
The present study is designed to investigate the hypolipidemic effect of the hot-water extract from the leaves of Dendropanax morbifera L. (DMWE) in hyperlipidemic rats. Thirty male 5-week-old rats were grouped as follows: Normal control (NC) given distilled water; hyperlipidemic control (HC) administered with distilled water; drug treatment (DT) orally administered with atorvastatin (10 mg/kg body weight (BW)); DMWE-treated groups (DM-50, DM-100 and DM-200) treated with DMWE 50, 100 and 200 mg/kg BW, respectively. All groups (except for NC) were fed a high-fat diet during the experiment. After 4 weeks of administration, the BW of all groups treated with DMWEs significantly increased compared to that of HC (p<0.05) and showed no significant difference compared to that of NC. In addition, serum total cholesterol levels in all groups treated with DMWEs were meaningfully decreased, compared to that in HC (p<0.05). In serum triglyceride (TG) and low-density lipoprotein-cholesterol levels, both DM-100 and DM-200 considerably decreased compared to HC (p<0.05), and no significant differences in TG levels were between DM-100 and DM-200. In high-density lipoprotein-cholesterol levels, DM-200 was statistically different compared to HC, and there were no significant differences between DM-100, DM-200 and DT. Furthermore, aspartate transaminase and alanine aminotransferase concentrations of DM-100 and DM-200 were significantly decreased compared to those of HC (p<0.05). From results portrayed above, DMWE at the concentration of 100 mg/kg BW has been identified to be effective in the treatment of hyperlipidemic rats.
This study investigated the preventive effect of Dendropanax morbifera leaf extracts (DMLEs) drew out with water, 30, 50 and 70% ethanol against alcohol-induced hepatotoxicity in vitro and vivo. The 3-(4,5-dimethylthiazol-2-yl)-2,5-dipenyltetrazolium bromide (MTT) assay was performed to assess cytotoxic activity of DMLEs, and the half-maximal inhibitory concentration (IC50) ranged between 1.11 and 2.08 mg/mL on Hep3B cells. In preventing ethanol-induced-hepatotoxicity on Hep3B cells, 30 and 50% ethanol DMLEs were significantly effective compared to the 5% ethanol treatment control. In addition, the 30% ethanol DMLE was orally provided to rats 30 min prior to the administration of ethanol (3 mL/kg body weight). At 1, 3 and 5 h after ethanol treatment, the plasma levels of ethanol and acetaldehyde were determined. The 30% ethanol DMLE effectively decreased the plasma ethanol levels during 5 h but increased the plasma acetaldehyde levels until 3 h and then significantly decreased at 5 h, as compared to the control. These results indicate that the 30% ethanol DMLE possesses a potent preventive effect against ethanol-induced liver toxicity in Sprague-Dawley rats.