The objective of this study is to establish the shelf life of non-pasteurized whole egg, egg yolk and egg white liquid. Each sample was stored for two weeks at 5oC, 10oC, 15oC, and 25oC, and then sensory, microbial, and physicochemical tests were performed periodically. The estimation of shelf life was based on the microbial standards of total viable counts and coliforms. The chemical properties highly correlated with the sensory evaluation were also used. Our results showed that the shelf life was the most influenced by microbial properties. Exceptionally, however, whole egg and white liquid stored at 5oC and 10oC with limited bacterial growth were affected by chemical property. The shelf life of the three non-pasteurized liquids was calculated to be less than one day at over 15oC. At 5oC and 10oC, the shelf life was calculated to be 5 d and 1 d for egg yolk liquid, 5 d and 5 d for egg white, and 7 d and 5 d for whole egg, respectively. Therefore, it is advisable to establish reasonable shelf life in the more specific manner based on consideration of these findings.

The purpose of this study was to review regulatory management of the classification system and scope of veterinary medical devices in Korea. In Korea, the four categories of the classification system for veterinary medical devices (instruments, supplies, artificial insemination apparatus, and others) is somewhat differently than that for human medical devices (instruments, supplies, dental materials, and reagents for in vitro diagnostics). In 2013, veterinary medical devices were classified into approximately 1,400 items, whereas, human medical devices were classified into approximately 2,200 items. Dissimilar to human medical devices, veterinary medical devices have no individual identification codes for effective market management. In conclusion, it is necessary to introduce a device identification code system and re-examine scope of the classification system for veterinary medical devices in Korea.

본 연구에서는 국내 대표 식육인 소, 돼지, 닭, 오리의4종 식육과 염소, 양, 말, 칠면조의 4종 식육을 동시에 신속하게 감별할 수 있는 2 set의 multiplex PCR법을 개발하고자 미토콘드리아 16S RNA에서 종 특이부위를 선발하고 각 종에 대한 특이도를 높이기 위하여 인위적인 미스매치를 주어 프라이머를 제작한 후 8종 식육의 274개시료를 대상으로 특이도와 민감도를 조사하였다. 그 결과소, 돼지, 닭, 오리 모든 시료에서 각각 279, 94, 192, 477 bp의 증폭산물이, 말, 양, 염소, 칠면조의 모든 시료에서 각각 152 bp, 271 bp, 670 bp, 469 bp에서 뚜렷한 PCR 유전자 산물이 확인되어 모든 축종에서 100%의 특이도를 나타내어 축종별 감별력이 우수한 것으로 나타났다. 8종의 축종별로 DNA를 10 ng/μl으로 정량한 후 혼합물을 10배씩 단계 희석하여 반응여부를 조사한 결과, 소, 돼지, 오리에서는 100 fg까지, 닭에서는 1 pg까지 검출됨을 확인할수 있었다. 소, 돼지, 닭, 오리고기를 99.9%, 99%, 90%,70%, 50%, 30%, 10%, 1%, 0.1%의 비율로 혼합한 식육과 83℃ 20분, 100℃ 30분, 121℃ 10분에서 각각 열처리한 가열 혼합육에 대하여 검출한계를 조사한 결과 마지막단계의 희석 비율인 모든 혼합육의 0.1%에서 검출이 가능하였으며, 열처리 혼합육에서는 닭에서는 1% 농도에서소와 돼지의 혼합육에서 0.1% 농도에서 검출되어 민감도가 높음을 확인할 수 있었다. 본 연구에서 개발된 multiplex PCR법은 특이도 및 민감도에 있어서 국내 대표 식육을 감별하는데 있어서 유용한 것으로 평가된다.

In this study, we investigated and analyzed the registration, sales and regulatory management system of in vitro diagnostic veterinary medical reagents (IVDVMRs) in Korea. The registration of IVDVMRs has gradually increased since 2000, and total of 233 products from 58 companies were registered from 1975 to 2014. The market size of IVDVMRs is estimated to be approximately 12 billion Won per year from 2011 to 2013: the export sales and proportion was estimated to be 36.8% as 4.4 billion Won in 2013. Of these products, the ranking of the sales were canine heartworm, bovine tuberculosis, swine fever, porcine reproductive and respiratory syndrome, canine distemper+adenovirus+parvovirus disease, foot and mouth disease, etc. In vitro diagnostic human medical reagents were diverted biological medicine from the medical devices by the revision of the Pharmaceutical Affairs Law Enforcement Regulations in 2014 in Korea. In contrast, in vitro diagnostic devices for animal were still managed as medical devices and biological medicines, respectively. The diagnostic reagents for infectious diseases have neither classification nor grade systems. Good manufacturing practices (GMP) requirements on IVDVMRs were also exempted from the current system. This study suggested that the registration of the IVDVMRs has increased since 2005, and regulations of these devices should be improved for the effective operating system.

In this study, two commercial PCR and ELISA test kits were examined for identification of eight animal species (beef, pork, chicken, duck, turkey, goat, lamb, and horse) from raw meat and meat products in Korea. The detection limit in RAW meat ELISA kit® on three types of meat samples blended with beef, pork and chicken, demonstrated that all meat species were differentiable down to 0.2%. RAW meat ELISA kit® on animal species resulted in differentiation rate of 94.5% for beef, 93.3% for pork, 90% for lamb, and 100% for chicken, duck, turkey, goat, and horse. In contrast, Powercheck Animal Species ID PCR kitTM resulted in 100% specificity at 0.05% limit of detection for all meat species. The detection limit of Cooked Meat ELISA kit® on mixed meat samples heat-treated with different temperatures and times, resulted in 0.1% for all heat-treated mixed meat except for chicken at 1.0%. Additionally, ELISA kit on sixty meat products resulted in specificity of 31.8% for ham, 13.6% for sausages, and 12.5% for ground processed products, and relatively low rate for more than 2 types of mixed meats. On the contrary, meat species differentiation using PCR kit showed higher percentage than that using ELISA kit®: 50.0% for ham, 41.7% for sausages, and 28.6% for ground processed meat. Futhermore, PCR kit on 54 dried beef meats detected pork genes in 13 products whereas ELISA kit showed negative results for all products. Hence, the possibility of cross-contamination during manufacturing process was investigated, and it was found that identical tumblers, straining trays, cutters and dryers were used in both beef and pork jerky production line, suggesting the inclusion of pork genes in beef products due to cross-contamination. In this study, PCR and ELISA test kits were found to be excellent methods for meat species differentiation in raw meat and heat-processed mixed meat. However, lower differentiation rate demonstrated in case of meat processed products raised the possibility of inclusion of other species due to cross-contamination during manufacturing process.

The current standard solutions for somatic cells used for calibration of electronic somatic cell counts as reference material in raw milk are preserved with bronopol, boric acid, sodium azide, or potassium dichromate, and have a shelf-life of only up to 6 days at 4 ± 2℃. In the present study, a set of somatic cell standard solutions (SCSS) with a stability of 5 months for calibration of electronic instruments was developed. Somatic cells collected from cow’s milk and stored in a bulk tank at a dairy plant were treated with 10% formaldehyde in order to improve stability, and then separated by centrifugation. The resulting somatic cell suspension was preserved with glycerin, thimerosal, and dimethyl sulfoxide, and diluted in 3% processed skim milk solution ranging from 200,000～250,000 (low level), 350,000～ 450,000 (medium level), and 550,000～650,000 (high level) cells/㎖. Each SCSS was verified by direct microscope somatic cell counting (DMSCC), C-reader, and commercial standard samples. The average somatic cell count determined by DMSCC was 248, 214, 226 × 103 cells/㎖, 436, 382, 420 × 103 cells/㎖, and 612, 595, 609 × 103 cells/㎖. The coefficient of variation representing the repeatability of DMSCC decreased as the number of cells increased, and was <10.0% in almost all SCSS samples (range 4.6～7.1%). No statistically significant difference in somatic cell concentration was observed after storage at refrigeration temperature (2～6℃) over a period of 22 weeks (5 months). The stabilized SCSS may be useful as a reference material for determination of somatic cell count and quality control in testing of bovine raw milk.

We compared between an automated most-probable-number technique TEMPO®TVC and traditional plating methods PetrifilmTM for estimating populations of total aerobic bacteria in various livestock products. 257 samples randomly selected in local retail stores and 87 samples inoculated with E. coli ATCC 25922, Staphylococcus aureus ATCC 12868 were tested in this study. The degree of agreement was estimated according to the CCFRA (Campden and Chorleywood Food Research Association Group) Guideline 29 and the agreement indicates the difference of two kinds methods is lower than 1 log base 10(log10). The samples of hams, jerky products, ground meat products, milks, ice creams, infant formulas, and egg heat formed products were showed above 95% in the agreement of methods. In contrast, proportion of agreement on meat extract products, cheeses and sausages were 93.1%, 92.1%, 89.1%, respectively. One press ham and five sausages containing spice and seasoning, two pork cutlets containing spice and bread crumbs, two meat extract product and two natural cheeses and one processing cheese with a high fat content, and one ice cream containing chocolate of all samples showed the discrepancy. Our result suggest that TEMPO®TVC system is efficient to analyses total aerobic bacteria to compare manual method in time-consuming and laborious process except livestock products having limit of detection.

This paper describes the epidemiological characteristics of bovine tuberculosis in Korea during January 2000 to September 2004, when the incidence of bovine tuberculosis increased markedly: a total of 1,054 herds (4,197 cattle) were confirmed to be infected with Mycobacterium bovis during this period. Based on the record of epidemiological investigation, introduction of purchased cattle (22.9%, 125/545) into a farm was the most frequent transmission route of M. bovis infection. On 31.7% (335/1,054) of the infected farms, recurrent infection occurred more than once before the disease has been eradicated completely. The highest rate of recurrence was detected around 70 days after the initial test of the infected herd, which seems to be related to current regulation on the test of animals that cohabited with those previously diagnosed with infection in farms, rather than to the characteristic of the disease. Although the current eradication program has been effective in controlling the disease in dairy cattle in Korea, control measures more specific to beef cattle may be needed because infection rate in beef cattle continues to increase in recent years.

We investigated the prevalence of the Listeria monocytogenes from livestock processed products in processing plants and retail markets of Korea from 2010 to 2011. A total of 1,380 samples were collected; Meat processed products such as cooked ham and sausage, jerked meat, and meat extract products. Milk processed products such as milk, butter, cheese, and ice cream. Egg processed products such as whole egg liquid and pidan. L. monocytogenes were isolated from samples using listeria enrichment broth, fraser broth and Oxford agar, and counted in Oxford agar. The three of L. monocytogenes strains (1.16%) were isolated from sausages, two (0.73%) from mixed pressed ham and one (0.51%) from jerked meat, respectively. The colony forming unit (CFU) of L. monocytogenes from all samples were below 10 CFU/g. The four isolates (66.6%) were 1/2b except two isolates (1/2a) in the serotypes. Further studies are needed to understand the transmission route of L. monocytogenes, including a survey of food handlers, environments of retail markets, and all potential risk factors in cooked sausages, mixed pressed hams, and jerked meat processing.

A total of 222 udder-half milk samples of lactating goats were collected from two herds in Korea during 2008 and all samples were subjected to bacteriological examination. Somatic cell counts (SCC) were also determined for all samples except for 13 (5.9%), which were collected from halves of udders with clinical mastitis. A total of 85 bacteria were isolated from 82 (36.9%) of 222 milk samples tested. Staphylococci were the predominant pathogens, accounting for almost 70% of the isolates: Coagulase negative staphylococci (CNS) and S. aureus constituted 55% (47/85) and 14.1% (12/85), respectively. Among 209 samples tested for SCC, bacteria were isolated from 36 of 115 (31.3%) samples with SCC of <1×106 cells/㎖ and 38 of 94 (40.4%) samples that had SCC of ≥1×106 cells/㎖, respectively. All S. aureus were detected from samples with SCC of ≥1×106 cells/㎖, while 25 of 47 (61.0%) CNS were isolated from milk samples with SCC of <1×106 cells/㎖. Mean SCC of milk samples that harbored S. aureus and CNS was 4,787×103 cells/㎖ and >1×106 cells/㎖, respectively. All S. aureus and CNS isolates were susceptible to all antimicrobials tested except for penicillin, to which 2 (16.6%) S. aureus and 12 (25.5%) CNS isolates showed resistance.

Toxocara (T.) canis, round worm of dogs and cats, is probably the most common gastrointestinal helminthes of domestic canid and is ascarid nematodes in the order Ascaridida, family Toxocaridae. The prevalence of patent toxocariasis is highest in the young dogs and much less common in adult dogs. There are few reports on the status of T. canis prevalence of dogs in Korea. Few cases of human visceral larva migrans also reported in Korea. However, as far as we know, there is no report on the canine toxocariasis case determined by pathological findings in Korea until now. In this research, we diagnosed canine toxocariasis by fecal egg test and pathologic findings in 2-month old two Pointer dogs. Typical T. canis eggs were detected in the fecal test. Numerous adult ascarids in the lumen of small intestine and stomach in one dog and multifocal white necrotic lesions in lung, liver, and kidney in another dog were observed grossly. Histologically, multifocal necrosis, eosinophilic inflammation and intralesional ascarid larva were prominent findings in the lung, liver and kidney.

For the screening of Brucella antibodies in pig, 2,140 pig serum samples were collected from six slaughter house in Korea between 2006 and 2007. The Rose Bengal test (RBT) and serum agglutination test (SAT) were used for initial screening for specific antibodies to Brucella, and competitive enzyme-linked immunosorbent assay (C-ELISA) was used for confirmation of presence of serum antibody for Brucella. Overall, 575 (26.9%) samples resulted in seropositive in RBT. In SAT, 50 (2.3%) and 10 (0.5%) samples showed suspicious positive and positive reaction, respectively, however, all sera tested in this study showed a negative reaction in C-ELISA. SAT and C-ELISA might be applicable as a tool for screening of swine brucellosis.

To determine the prevalence of Campylobacter jejuni and Campylobacter coli in meats, a total of 4,161 samples (1,953 domestic and 2,208 imported) were collected from 304 slaughterhouses nationwide and registered cold storages for imported meats in Korea during 2005～2009. The isolation rates of C. jejuni and C. coli in domestic beef, pork, chicken and duck meats were 0.1% (1/630), 0% (0/630), and 0.1% (1/644), 0% (0/644) and 20.5% (125/609), 10.2% (62/609) and 25.7% (18/70), 20.0% (14/70), respectively. In the case of imported meats, C. jejuni were isolated from 0.1% (1/943) and 15.2% (83/546) of pork and chicken meats, respectively, and C. coli were detected only from 4.8% (26/546) of chicken meats. Neither C. jejuni nor C. coli were detected from imported beef, and C. coli were also not detected from imported pork. In conclusion, chicken meats had much higher rate of contamination with Campylobacter compared to beef and pork. Therefore, HACCP system that is now mandatory for slaughterhouses should be actively practiced for safe and sanitary processing, handling, and marketing of chicken meats. In addition, all critical control points should be determined by processing procedures at processing plants as well as farms and slaughterhouses, and monitoring should be carried out at regular intervals.