• Korean Journal of Veterinary Research
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• v.37 no.1
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• pp.137-146
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• 1997

About Clostridium perfringens causing clinically necrotic enteritis or isolated from the intestinal contens of healthy chicken, We examined the usefulness of a rapid identification method by gas-liquid chromatography as well as the types of toxins. For this study, there were used 169 chickens including 116 broilers, 27 layers and 26 breeders which collected from 9 healty flock and 21 diseased flock showing necrotic enteritis. Among them, Cl perfringens was isolated from 30 chickens(17.8%) including 7 breeders(26.9%), 5 layers(18.5%) and 18 broilers(15.5%). Isolation of Cl perfringens was mainly from ceca (100%) and followed by small intestines(70.0%) and livers(16.7%), respectively. Average concentration of the pathogen in intestinal contents was $10^{3.8}CFU/g$ in cases occuring necrotic enteritis and on the contrary $10^{3.8}CFU/g$ in healthy cases. All isolates tested showed the same characterstics in biochemical tests compared to those in standard strain. Analysis of gas-liquid chromatography to volatile fatty acids produced by Cl perfringens in PYG broth showed the typical peaks of acetic and butyric acids compatible with the standard chromogram and was confirmed as a effective and reliable tool for rapid identification of the bacteria. Toxin types of 30 strains were mostly classified in A type(26 isolates) and the rest in C type(2 isolates) and unidentifed type(2 isolates). All the isolates were highly susceptible to amphicillin, amoxicillin and cephalothin.

• Parasites, Hosts and Diseases
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• v.57 no.3
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• pp.257-264
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• 2019

We tried a series of morphological and molecular approaches to identify a new species of Stellantchasmus (Digenea: Heterophyidae) originating from the wrestling half-beaked fish, Dermogenys pusillus of Thailand. Adult worm samples of the new species were recovered from hamsters experimentally infected with the metacercariae from D. pusillus in Thailand. Two isolates (Thai and Korean) of Stellantchasmus falcatus were used as comparative control groups. Worm samples of 3 Stellantchasmus groups were morphologically observed and molecularly analyzed with the mitochondrial cytochrome c oxidase 1 gene. The morphological characteristics of S. dermogenysi n. sp. are similar to S. falcatus originating from brackish water fish, but minor difference was noted including the absence of the prepharynx, position of the ovary near the ceca end, smaller body size, and shorter esophageal length. A phylogenetic tree derived from neighbor-joining and maximum-likelihood methods suggests that S. dermogenysi n. sp. is separated from S. falcatus supported by high bootstrap values. The relative divergences persist between these host-specific trematodes, which we suggest should be recognized as 2 distinct species. Comparisons of S. dermogenysi n. sp. with S. falcatus isolated from mullets in Thailand and Korea indicate a genetic divergence of mitochondrial DNA of 19.4% and 21.7%, respectively. By the present study, a new species, Stellantchasmus dermogenysi n. sp. (Digenea: Heterophyidae), is proposed in Thailand based on molecular evidences, in addition to minor morphological differences between S. falcatus and the new species.

• Journal of Animal Science and Technology
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• v.63 no.1
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• pp.69-76
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• 2021

This experiment was conducted to evaluate the effect of supplementing enzyme cocktail on growth performance, digestibility of nutrients, and monosaccharide concentration in ileum and ceca of broiler chickens fed wheat-based diets. A total of 600 male broilers (42.26 ± 1.76 g, 0 day old) were used for 35 days of feeding trial consisting of 2 phases (starter phase from d 0 to 21 and finisher phase from d 21 to 35). Four dietary treatments were prepared based on wheat diets containing four levels of enzyme cocktail supplementation at 0, 0.2, 0.3, and 20 g/kg. Overall, dietary enzyme cocktail supplementation decreased feed conversion ratio (linear p = 0.007; quadratic p = 0.013) and improved (linear p < 0.05) the apparent ileal digestibility of dry matter (DM), crude protein, and soluble and insoluble non-starch polysaccharides. The apparent total tract digestibility of DM and gross energy were increased (linear p < 0.01) with increasing supplementation levels of the dietary enzyme cocktail. The concentrations of arabinose, xylose, mannose, and glucose in ileal digesta were linearly increased (p < 0.01) with increasing enzyme cocktail supplementation levels. In addition, the quadratic effect was observed (quadratic p = 0.046) in mannose concentration of ileal digesta. The concentration of arabinose, xylose, mannose, and galactose in cecal digesta was increased (linear p < 0.05) with increasing dietary enzyme cocktail supplementation levels. The supplementation of enzyme cocktail efficiently increased the utilization of nutrients in broiler and there was no adverse effects of high dosage supplementation level.

• Parasites, Hosts and Diseases
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• v.59 no.3
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• pp.303-309
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• 2021

In this study, we intended to describe an unrecorded species of heterophyid trematode recovered from the small intestine of a Korean raccoon dog, Nyctereutes procyonoides koreensis, in Korea. A total of 13 small flukes were collected from a deceased Korean raccoon dog which was found in Chuncheon-si, Gangwon-do, Korea in May 2017. The trematode body were covered with many small spines, rectangular, broader than long, 807-1,103 ㎛ long and 1,270-1,550 ㎛ wide. Oral sucker in the anterior end slightly smaller than acetabulum. Pharynx muscular and well developed. Esophagus relatively long and sigmoid. Acetabulum small and located at median in anterior 2/5 portion. Ceca bifurcated at the anterior of genital pore and acetabulum and terminated at testis level. Testes larger, deeply lobed and located at the near of posterior end of body. Ovary small, triangular and located at the slight left of median and the anterior of left testis. Vitelline follicles dendritic and extend from the middle level of esophagus to the posterior portion of body. Eggs embryonated, operculated, small and 33-35×15-16 ㎛ in size. Based on the morphological characteristics, the small heterophyid flukes recovered from the small intestines of Korean raccoon dog, N. procyonoides koreensis, were identified as Euryhelmis squamula (Digenea: Heterophyidae). Accordingly, this species of heterophyid flukes is to be a new trematode fauna in Korea by this study.

• Animal Bioscience
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• v.37 no.6
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• pp.993-1000
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• 2024

Objective: This study was conducted to investigate the differential expression of the major histocompatibility complex (MHC) gene region in Eimeria-infected broiler. Methods: We profiled gene expression of Eimeria-infected and uninfected ceca of broilers sampled at 4, 7, and 21 days post-infection (dpi) using RNA sequencing. Differentially expressed genes (DEGs) between two sample groups were identified at each time point. DEGs located on chicken chromosome 16 were used for further analysis. Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis was conducted for the functional annotation of DEGs. Results: Fourteen significant (false discovery rate <0.1) DEGs were identified at 4 and 7 dpi and categorized into three groups: MHC-Y class I genes, MHC-B region genes, and non-MHC genes. In Eimeria-infected broilers, MHC-Y class I genes were upregulated at 4 dpi but downregulated at 7 dpi. This result implies that MHC-Y class I genes initially activated an immune response, which was then suppressed by Eimeria. Of the MHC-B region genes, the DMB1 gene was upregulated, and TAP-related genes significantly implemented antigen processing for MHC class I at 4 dpi, which was supported by KEGG pathway analysis. Conclusion: This study is the first to investigate MHC gene responses to coccidia infection in chickens using RNA sequencing. MHC-B and MHC-Y genes showed their immune responses in reaction to Eimeria infection. These findings are valuable for understanding chicken MHC gene function.

• Parasites, Hosts and Diseases
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• v.27 no.2
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• pp.87-100
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• 1989

Eimeria tenella, an intracellular protozoan parasite infecting the epithelial cells of the ceca of chickens, causes severe diarrhea and bleeding that can lead its host to death. It is of interest that 2. tenezla first penetrate into the mucosal intraepithelial Iymphocytes (IEL) before they parasitize crypt or villous epithelial cells. This in vitro study was undertaken to know whether the penetration of E. tenella into such a lymphoid cell is a beneficial step for the parasite survival and development. Three sequential experiments were performed. First, the in vitro established bovine kidney cell line, MDBK cells, were evaluated for use as host cells for E. tenella, through morphological observation. Second, the degree of parasite development and multiplication in MDBK cells was quantitatively assayed using radioisotope labelled uracil ($^3H-uracil$) . Third, the E. tenella sporozoites viability was assayed after preincubation of them with thicken spleen cells. E. tenella oocysts obtained from the ceca of the infected chickens were used for the source of the sporozoites. Spleen cells (I) obtained from normal chickens (FP strain) were preincubated with the sporozoites (T) at the E:T ratio of 100:1, 50:1 or 25:1 for 4 or 12 hours, and then the mixture was inoculated into the MDBK cell monolayer. Morphologically the infected MDBK cells revealed active schisogonic cycle of E. tenella in 3~4 days, which was characterized by the appearance of trophozoites, and immature and mature schizonts containing merogoites. The 3H-uracil uptake by E. tenella increased gradually in the MDBK cells, which made a plateau after 48~60 hours, and decreased thereafter. The uptake amount of $^3H-uracil$ depended not only upon the inoculum sixte of the sporozoites but also on the degree of time delay (preincubation; sporozoites only) from excystation to inoculation into MDBK cells. The 3H-uracil uptake became lower as the preincubation time was prolonged. In comparison, after preincubation of sporozoites with spleen cells for 4 or 12 hours, the 3H-uracil uptake was significantly increased compared with that of control group. From the results, it was inferred that, although the penetration of E. tenella sporozoites into the lymphoid cells such as IEL is not an essential step, it should be at least a beneficial one for the survival and development of sporozoites in the chicken intestine.

• Korean Journal of Poultry Science
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• v.45 no.3
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• pp.167-174
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• 2018

This study examined the effects of dietary processed pine needle tree powder (PPNP) on growth performance, visceral organ parameters, ileal digestibility, blood metabolites and ileal morphology of broiler chickens for 5-week after hatch. In total, 220 1-day-old male Ross 308 broiler chicks were randomly allocated to 30 pens (seven birds per pen), and each pen was assigned to one of five dietary treatments, a diet without PPNP (control) and diets with 0.5%, 1.0%, 1.5% and 2.0% PPNP. The body weight and feed intake were measured weekly. One bird from each pen was selected randomly and gently euthanized to collect the blood, visceral organs and digesta samples on 2, 3 and 5 week of age. Birds fed 2.0% PPNP showed decreased (P<0.05) overall body weight, average daily gain and average daily feed intake compared to those fed control, 0.5 and 1.0% PPNP. The small intestine length increased (P<0.05) as the level of PPNP in the diet increased. A deeper crypt depth was observed (P<0.05) when birds fed 2.0% PPNP compared to those fed the control diet at week 2. A higher V:C ratio was observed (P<0.05) in birds fed 1.0% PPNP than in those fed other treatments at week 3. Ileal protein digestibility improved (P<0.05) when birds fed 0.5% and 1.0% PPNP compared to that in those fed the control diet at week 3. The feed conversion ratio, ileal dry matter digestibility and blood urea nitrogen and cholesterol, and gizzard and ceca weights were not affected (P>0.05) by supplementation of any levels of PPNP. These results demonstrated that inclusion of PPNP in broiler diets could be a possible factor in improving overall growth performance suggesting early gut development when 1% PPNP is supplemented.

• Korean Journal of Poultry Science
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• v.34 no.2
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• pp.129-136
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• 2007

The objectives of this study were to examine the effects of Korean mistletoe (KM) on performance and blood characteristics in broiler chickens. A total of four hundred eighty, 1-d-old male broiler chicks (Ross) were divided into 4 groups with 4 replicates of 30 birds each. The treatments were NC (antibiotics-free diet), PC (NC diet added antibiotics), 0.5% KM (NC diet added 0.5% of KM) and 1.0% KM (NC diet added 1.0% of KM), and the birds were raised for 49 days. There were no significant differences in feed intake and body weight gain among treatments. On d 49, the relative length of jejunum in 1.0% KM tended to be increased or significantly (P<0.05) increased compare to those of other groups. On d 35, the colony forming unit of Salmonella spp. of ceca significantly (P<0.05) decreased by feeding KM. The counts of lymphocyte of KM significantly (P<0.05) increased compare to those of the PC.

• Journal of Veterinary Clinics
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• v.26 no.6
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• pp.591-594
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• 2009

Acute and massive death was noted in 10-week-old chickens, broiler breeder, housed in the floor pens. The number of dead chickens exceeded 20 birds each day. Grossly, fibrinous peritonitis with adhesion of mesenteries and intestinal organs was noted. The ceca were enlarged, expanded, and thickened with congestion. Cecal lumen was distended with a caseous core composed of serous, fibrinopurulent, and hemorrhagic exudates with desquamated masses of epithelial cells. The liver had multifocal white irregular necrotic foci surrounded by a raised ring. Light and electron microscope revealed Histomonas meleagridis in the liver with its characteristic structures and not in the intestinal mucoca and submucosa. In this case, the examination of parasite, larvae and egg was conducted more carefully; however, we could not find eggs or worms of Heterakis gallinarum in the dead or live chickens and earthworms in the soils of floor pens. Therefore, we concluded that an outbreak of blackhead disease probably occurred by direct transmission of histomonads from chickens to chickens in this case.

• Korean Journal of Poultry Science
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• v.8 no.1
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• pp.7-14
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• 1981

The experiment using Anake broiler strain chicks was conducted to study the effort fungistatic agents on microbial counts, Ins of nutrient, growth rate and feed efficiency of the broiler. Feed was adjusted to 12% and 15% moisture level during hot and high humidity season and sorbic acid at the level of 0.02%, 0.04% and Ca-propionic acid at the level 0.1% 0.2% was added. The results obtained were as follows. 1, The Addition of fungistatic agents could slightly reduce mold and yeast counts. The highest effect on inhibition of mold and yeast counts was observed for the addition of sorbic acid at 0.04% level to the fled contained 15% moisture. 2, Approximately 14% starch loss of ground corn was observed from the fred contained 15% moisture and the loss could be diminished to 3-7% by the addition of fungistatic agents with the superior effect of sorbic acid to Ca-propionic acid. 3. Approximately 15% fat loss was detected when high moisture fled was und and this was reduced to 7% by the addition of 0.04% sorbic acid to the feed. 4. Significantly higher growth rate (p＜0.05) during starter period was observed for low moisture feed added by sorbic acid compared with that for high moisture diet without fungistatic agents or with Ca-propionate at the level of 0.1%. 5. Significantly lower feed efficiency (p＜0.05) during starter period of high moisture feed without fungistatic agents was observed; hower no significant different response was detected by either moisturer level of kinds and levels of fungistatic agents used. 6. Significantly higher growth rate (p＜0.05) during finisher period of lower moisture feed with 0.04% sorbic acid was observed compared with that of high moisture fled without fungistatic agents or the feed added by 0.1% Ca-propionate level. 7. Significantly higher feed efficiency (p＜0.05) during finisher period of low moisture feed added by sorbic acid 0.02% or 0.04% level was found compared with that of high moisture feed without fungistatic agents and low moisture feed added by Ca-propionate at the level of 0.1% or 0.2%. 8. Mort bacteria, mold and yeast were observed in the ceca than in small intestine. The. moisture content of dict had no effect on intestinal microfloral counts. However, numbers of mold and yeast of intestine could slightly be reduced by fungistatic agents administration. 9. Nothing but encephalomalacia to chicks fed feed contained 15% moisture without addition of fungistatic agents was observed. In conclusion, addition of either sorbid acid at 0.04% level and Ca-propionate at 0.2% level to high moisture feed or reduced moisture level to 12% could be con-sidered more effective to enhance growth rate and fled efficiency of broilers during summer period.