• KOREAN POULTRY JOURNAL
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• v.6 no.3 s.53
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• pp.95-98
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• 1974

감부로병(Gumboro Disease)으로 알려진 이병은 최근에 전염성훼브리샤스낭병 바이러스(Infectious Bursal of Fabricius Disease Virus:IBDV)에 의해서 일어난다는 것이 밝혀졌다. 이 전염병은 주로 3$\~$6주령의 닭에만이 발생하며 닭이 이에 감염되면 침울해지고 몸의 균형을 잡지 못하며 떨며 항문주위의 틀이 더렵혀지는 등의 증세를 나타낸다. 우리나라에서는 아직 정식 발생보고가 없으나, 미국, 구라파 일본등지에서는 많은 발생보고가 있다. 감염내과된 닭은 5$\~$7일만에 회복되며 회복된 닭은 후유증(後遺症)이 없다. 임상소견으로는 훼브리샤스낭(囊)이 젤라친과 같은 막과 크림이나 치즈같은 물질을 같으며 비대(肥大)해지고 야외에서 발생한 닭의 경우 근육의 출혈과 가끔 신장(腎臟)이 창백, 또는 종장등의 변화가 일어난다. 따라서 본란을 통해서 이 병에 대한 증상과 바이러스의 분리 병리조직학적인 진단방법등에 대한 정보를 제공하여 우리 나라의 발생여부를 확인하는데 참고자료에 공여코저한다.

• Korean Journal of Poultry Science
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• v.50 no.4
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• pp.231-240
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• 2023

Infectious bursal disease (IBD) is an acute, highly contagious, and immunosuppressive disease in young chickens, and causes considerable economic losses to the poultry industry. More than 30 years ago, an antigenic variant IBDV (avIBDV) was reported in chicken farms in the United States. Recently, a novel avIBDV exhibited clear differences in molecular characteristics compared with previous variant strains. This study investigated the molecular characteristics of recently isolated avIBDV strains in Korea. Strains of avIBDV were confirmed by reverse transcription PCR (RT-PCR) and were propagated in 10-day-old specific-pathogen-free (SPF) embryonated chicken eggs through chorioallantoic membrane (CAM) inoculation. Multiple sequence alignment and phylogenetic analyses of hypervariable regions VP2 gene revealed that the strains originated from two different avIBDV lineages (G2a and G2d). In our results, we confirmed the co-existence and prevalence of avIBDV genogroup G2a and G2d in chicken farms. It is necessary to study the protective efficacy of current vaccines against avIBDVs.

• Korean Journal of Veterinary Research
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• v.43 no.3
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• pp.439-448
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• 2003

The VP2 gene of infectious bursal disease virus (IBDV) Chinju which was previously detected in Chinju, Korea was cloned and sequenced to establish the information for the development of genetically engineered vaccines and diagnostic reagents against IBDV. The nucleotide sequence of the entire Chinju VP2 gene consisted of 1,356 bases long encoding 452 amino acids in a single open reading frame (ORF). It consisted of 368 adenine (27.1%), 363 cytosine (26.8%), 339 guanine (25.0%) and 286 thymine (21.1%) residues. The predicted $M_r$ of the Chinju VP2 protein was 48 kDa, and the protein contained 13 phosphorylation sites by protein kinase C, casein kinase II or tyrosine kinase, whereas 3 asparagine-linked glycosylation sites were recognized. The nucleotide sequence of Chinju VP2 ORF had a very close phylogenetic relationship with 98-99% homology to that of the very virulent IBDVs (vvIBDVs) HK46, OKYM, D6948, UK661, UPM97/61 and BD3/99. Also, the Chinju VP2 protein revealed a very close phylogenetic relationship with 99-100% homology to that of these vvIBDVs. The Chinju VP2 protein had 100% amino acid identity in the variable region of residues 206-360 with that of the D6948, HK46, OKYM and UK661, as well as 100% identity in two hypervariable regions of residues 212-224 and 314-324 with those of the D6948, HK46, OKYM, UK661, UPM97/61 and BD3/99. The amino acid sequence of the chinju VP2 protein contained a serine-rich heptapeptide of SWSASGS as in these vvIBDVs.

• Korean Journal of Veterinary Service
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• v.22 no.3
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• pp.247-255
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• 1999

Sequential morphologic changes in the lymphoid organs were examined after ocular and cloacal inoculation in 3weekold chicks with a highly virulent strain (SH/92) of infectious bursal disease virus (IBDV). The infected chickens were sacrificed at 6, 12, 24, 48, 72, and 96 hrs post inoculation (Pl), and thymus, harderian gland, ceacal tonsil, and spleen were observed. Histologically, the significant lesions were characterized by lymphocyte depletion and the earliest detectable changes were evident at 12 hrs Pl. In thymic cortex, lymphoid depletion with apoptosis and prominent "tingible body macrophages" were observed. As the infection advanced, the lesions showed more severe changes. Dying cells were characterized either by capping of nuclear chromatin (apoptosis) or by cytoplasmic swelling (necrosis). In situ staining for apoptosis, some lymphoid cells revealed typical positive reaction, even the stainability was variable depend on every lymphoid organs. These results suggest that IBBV (SH/92) cause severe damage both primary and secondary lymphoid organs, and both T and B lymphocytes. Also the lymphoid depletion of these organs is caused by necrosis and apoptosis induced by IBDV.d by IBDV.

• Korean Journal of Poultry Science
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• v.38 no.3
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• pp.181-189
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• 2011

A 5-month (May to November in 2009) monitoring program for five viral pathogens in litter, such as avian influenza virus A (AIV), infectious bronchitis virus (IBV), infectious bursal disease virus (IBDV), fowl adenovirus (FAdV), and chicken infectious anemia virus (CIAV) was conducted in 62 flocks at 31 broiler farms (two flocks in each farm) in Korea in 2009. Viral pathogens were examined twice (before and at the end of the rearing period) at 31 broiler farms, and included fresh litter (n = 16) and recycled litter (n = 15) farms. Thirty-seven viruses (14 IBVs, 2 IBDVs, 9 FAdVs, and 12 CIAVs) were isolated from 75% (12/16) and 73% (11/15) of fresh litter and reused litter farms during the period, respectively, indicating no difference in viral contamination rate between farms using new and reused litter. Of these isolates, three (two CIAVs and one IBDV) were isolated from recycled litter samples collected before the rearing period at three broiler farms, whereas the others (n=34) were isolated from fresh and recycled litter samples collected at the end of the rearing period. When the performances, involving viability, body weight, and feed conversion ratio, were compared, no significant differences were found between farms using fresh and recycled litter during the period.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.6
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• pp.884-891
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• 2006

The effect of dietary vitamin E supplementation on immune responses was studied in breeder chickens during the maturing period. In experiment 1, 17-week old female birds were fed corn-soybean meal based diets supplemented with either 0, 40, 80, 120, or 160 mg vitamin E (all-rac-${\alpha}$-tocopherol acetate)/kg diet for 19 weeks. In experiment 2, 23-week old male birds were fed the corn-soybean meal based diet supplemented with either 0, 20, 40, 80 or 160 mg vitamin E/kg diet for 8 weeks. The chickens were evaluated for growth performance, antibody titer to sheep red blood cell (SRBC), Newcastle disease virus (NDV), infectious bursal disease virus (IBDV) and infectious bronchitis virus (IBV), and skin response to phytohemagglutinin-P (PHA-P). The results showed that supplemental vitamin E improved body weigh gain of laying pullets during peak-laying period but had no significant effect on growth performance of cockerels. For cockerels, addition of 20 mg vitamin E/kg diet significantly enhanced (p<0.05) immune response to SRBC compared to those added with 0, 80 and 160 mg vitamin E/kg diet; addition of 20 mg vitamin E/kg diet had higher (p<0.01) antibody titer to IBDV than those added with 40-160 mg vitamin E/kg diet. No significant effects on immune response were observed in laying pullets fed supplemental vitamin E. The findings suggest that moderate supplementation of vitamin E may enhance immune responses to selective antigens in cockerels but excessive vitamin E may depress specific immune response.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.3
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• pp.396-403
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• 2009

Male broiler chicks were fed graded levels of organic zinc (zinc-methionine) supplementation to investigate the effects of partial or complete substitution of the organic zinc source for inorganic ones on the development of lymphoid organs and immunological responses. A total of 450 day-old male broilers were distributed into groups of 10 chicks and randomly assigned to nine experimental diets during a 42-day feeding trial. Dietary treatments consisted of two basal diets supplemented with 40 mg/kg added zinc as feed-grade Zn sulfate or Zn oxide in which, Zn was replaced with that provided from zinc-methionine (ZnMet) complex at the levels of 25, 50, 75 or 100%. Two randomly-selected birds from each pen replicate were bled and then slaughtered by cervical cutting on the final day of the trial to measure leukocyte subpopulations and relative weights of lymphoid organs. Among lymphoid organs, only thymus weight was affected (p<0.05) by dietary treatments. The sulfate-supplemented birds were heavier (p<0.01) in relative weight of thymus than oxide-supplemented birds. The 10 days of age-assessed cutaneous hypersensivity reaction was stronger in chicks fed ZnMet-containing diets. Dietary ZnMet supplementation caused (p<0.05) an increase in proportion of lymphocytes and consequently a decrease in heterophil to lymphocyte ratio. Diet fortification by zinc-methionine complex increased (p<0.01) Newcastle antibody titer at 19 days of age. Also, a similar response was observed in antibody titers at 6 and 12 d after infectious bronchitis vaccine administration. There was no significant effect of replacement of dietary zinc on antibody titer against infectious bursal disease virus (IBDV) at the 6th d post-vaccine inoculation; however, at d 12 after vaccination, ZnMet-fortified diets improved antibody titer against IBDV. Although dietary inclusion of ZnMet had no marked effect on primary antibody titer against sheep erythrocytes, effective responses were observed during secondary reaction from the viewpoint of both total antibody and immunoglobulin Y (IgY) titers. From the present findings, it can be concluded that dietary supplementation with organic zinc improves both cellular and humoral immune responses. It is necessary to replace 75% of supplemental inorganic zinc with organic ZnMet complex to achieve the optimum immunological responses in broiler chicks.

• Journal of Life Science
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• v.19 no.11
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• pp.1547-1552
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• 2009

This study was carried out to evaluate the supplementation effect of dietary natural plant extracts (NP: $Coxynil^{(R)}$, $Growell^{(R)}$ and $Respowell^{(R)}$) on broiler chickens. Forty thousand male broilers with 7 days adaptation after hatching were fed experiment diets for 34 days. The supplementation effects of NP on growth performance, blood parameters and biopsy were examined with twenty thousand broilers as the treatment group. Twenty thousand broilers for the control group (CON) were fed the diet with salinomycin-6, clopidol-25, enramycin-1, and BMD-2.5. In the diet of the treatment group, the antibiotics were replaced with 0.03%, 0.035% and 0.03% of $Coxynil^{(R)}$, $Growell^{(R)}$ and $Respowell^{(R)}$, respectively. The weight gain of the treatment group was increased but the feed intake was decreased, indicating that feed efficiency was increased compared to the CON. The mortality of the NP group was also lower compared to the CON group (1,008 birds to 1,693 birds), showing positive dietary effects from natural plant extracts. In the activity of infectious bursal disease virus (IBDV) and new cattle disease virus (NDV) antibodies, the NP showed lower antibody titer levels for both of IBDV and NDV compared to the CON. The levels of total cholesterol, HDL-cholesterol, globulin, and IgG in blood did not show significant differences between the groups. In the microscopic tissue analysis, no significant differences were detected. These results may suggest that a complex of three natural plant extracts can be used as alternative antibiotics in broilers.