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

• Korean Journal of Veterinary Service
• /
• v.25 no.4
• /
• pp.347-355
• /
• 2002

This experiment was performed to investigate apoptosis during undergoing pathogenesis of avian infectious bronchitis virus(IBV)-infected chicks. Sixteen days old chicks were infected with IBV, Massachusetts-41 strain(M-41, 10$^4$-10$^{5}$ EID$^{50}$ ) experimentally, they were autopsied to remove trachea, lung, kidney and cloacal bursa at 6hr, 12hr, 1 day, 3 day and 7 day post infection(PI) respectively for H-E and TUNEL staining. Grossly, mild serous, catarrhal exudate was observed in the trachea, nasal passages and sinuses nasal from 4 day PI. The cloacal bursa was swollen from 3 day PI. Histopathologically, the trachea was seen mild cellular infiltration, edema of the mucosa and submucosa, vascular congestion and mild hyperplasia of the epithelium from 6 hr PI and the changes were seen a little more severely on 7 day PI. It was observed that the cloacal bursa was getting more and more hyperplasia through the experiment. The nuclei degeneration were shown in the kidney on 7 day PI. No specific changes were seen in the lung. In TUNEL analysis, apoptotic cells showed sharp increasing at 12 hr PI and reaching a maximum on 1 day PI in the trachea, lung, kidney and cloacal bursa. And then apoptotic cells decreased gradually returning to a level of the control by 7 day PI in all the removed organs.

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

• Korean Journal of Poultry Science
• /
• v.37 no.2
• /
• pp.167-172
• /
• 2010

An immunochromatograhy (IC) based infectious bursal disease virus (IBDV) detection kit, which employed two anti-IBDV VP2 monoclonal antibodies, was evaluated for rapid diagnosis of infectious bursal disease virus (IBD). The detection limit of the IC kit for IBDV was $10^{3.1}$ to $10^{3.9}$ $EID_{50}$/mL, indicating that the IC kit detected IBDV sensitively as same as double antigen capture ELISA but less than a RT-PCR assay. The IC kit did not detect other viral pathogens such as Newcastle disease virus, infectious bronchitis, avian influenza virus, and infectious larynotracheitis virus. When applied to tissue samples of experimental chickens died 3 or 4 days post infection after very virulent IBDV (strain Kr/D62) infection, the IC kit detected IBDV in all samples of the bursa of Fabricius, spleen, kidney, cecal tonsil and in 87.5%, 37.5% and 0% of liver, thymus and proventriculus samples. In particular, BF tissue samples showed stronger signal bands than other tissues. Positive signal was observed. All except for one thymus sample of samples having negative results by the IC kit showed the same result with DAS-ELISA but RT-PCR assay detected IBDV in some of IC kit negative samples of thymus and proventriculus. When swab samples from the bursa of Fabricius of dead chickens (n=231) on field farms were tested, the sensitivity and specificity of the IC assay relative to RT-PCR was 100% (109/109) and 97.5% (119/122), respectively and kappa value between both assay was 0.97. The kit can provide a useful aid for rapid detection of IBDV in chickens under field circumstances.

• Pediatric Infection and Vaccine
• /
• v.25 no.2
• /
• pp.101-106
• /
• 2018

A 6-year-old boy with underlying hemolytic anemia of unknown etiology, atopic dermatitis, and recurrent urticaria visited our hospital because of acute respiratory failure induced by influenza A. Despite mechanical ventilation after endotracheal intubation along with inhalation of nitric oxide, respiratory acidosis and hypoxemia persisted. Veno-venous extracorporeal membrane oxygenation (VV ECMO) insertion was performed to provide respiratory support. After performing flexible bronchoscopy, we found that thick mucus plugs were obstructing the right bronchus intermedius and the upper lobe orifice. After bronchial washing and removal of the plugs, we were able to wean the patient off VV ECMO and transfer him to the general ward. He was discharged without any neurologic or pulmonary sequelae.

• Asian-Australasian Journal of Animal Sciences
• /
• v.25 no.2
• /
• pp.256-260
• /
• 2012

The objectives of this study were to investigate the immune responses of broiler chickens fed diets supplemented with different level of chromium methionine (CrMet) in heat stress (HS) condition. Two hundred and eighty eight male broiler chickens (Ross 308) were allocated to four treatment groups (supplementation with 0, 200, 400 or 800 ppb Cr in the form of CrMet) in a completely randomized design. The experiment was conducted at heat stressed condition and all birds were kept under temperature of $33{\pm}2^{\circ}C$. Antibody titers against Newcastle disease virus (NDV) and infectious bronchitis virus (IBV), heterophil to lymphocyte ratios (H/L), and concentration of plasma cortisol (CPC) were measured at 21 and 42 d. At 42 days of age two birds were chosen randomly from each replicate, slaughtered, spleen and bursa of Fabricius were collected, weighed and expressed as a percentage of live body weight. Antibody titers against NDV and IBV at 21 and 42 days of age in broiler fed supplemental CrMet were higher than in broiler chickens fed control diet (p<0.05). CPC level in broiler chickens fed CrMet were significantly (p<0.05) decreased. Increases in lymphocyte counts and consequently a decrease in heterophil to lymphocyte ratios in broiler chickens fed 800 ppb Cr were observed at 21 and 42 d. Supplementation with CrMet had no significant effect on lymphoid organs of broilers. The results suggest that dietary CrMet supplementation at a level of 800 ppb can improve some immune responses of broiler chickens under heat stress conditions.

• Journal of Veterinary Clinics
• /
• v.23 no.2
• /
• pp.105-110
• /
• 2006

A three-layer, feed-forward artificial neural network (ANN) with sixteen input neurons, three hidden neurons, and one output neuron was developed to identify the presence of infectious bronchitis (IB) infection as early as possible in laying hen flocks. Retrospective data from flocks that enrolled IB surveillance program between May 2003 and November 2005 were used to build the ANN. Data set of 86 flocks was divided randomly into two sets: 77 cases for training set and 9 cases for testing set. Input factors were 16 epidemiological findings including characteristics of the layer house, management practice, flock size, and the output was either presence or absence of IB. ANN was trained using training set with a back-propagation algorithm and test set was used to determine the network's capability to predict outcomes that it has never seen. Diagnostic performance of the trained network was evaluated by constructing receiver operating characteristic (ROC) curve with the area under the curve (AUC), which were also used to determine the best positivity criterion for the model. Several different ANNs with different structures were created. The best-fitted trained network, IBV_D1, was able to predict IB in 73 cases out of 77 (diagnostic accuracy 94.8%) in the training set. Sensitivity and specificity of the trained neural network was 95.5% (42/44, 95% CI, 84.5-99.4) and 93.9% (31/33, 95% CI, 79.8-99.3), respectively. For testing set, AVC of the ROC curve for the IBV_D1 network was 0.948 (SE=0.086, 95% CI 0.592-0.961) in recognizing IB infection status accurately. At a criterion of 0.7149, the diagnostic accuracy was the highest with a 88.9% with the highest sensitivity of 100%. With this value of sensitivity and specificity together with assumed 44% of IB prevalence, IBV_D1 network showed a PPV of 80% and an NPV of 100%. Based on these findings, the authors conclude that neural network can be successfully applied to the development of a screening model for identifying IB infection in laying hen flocks.

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

• Korean Journal of Poultry Science
• /
• v.46 no.4
• /
• pp.235-247
• /
• 2019

Serological monitoring has been conducted worldwide for early diagnosis of disease and monitoring of immune status in poultry. This study was conducted to evaluate the immune status of layers with sera submitted to the Avian Disease Laboratory, Chungbuk National University from 2015 to 2017. The test results were analyzed by the time submitted and by the age of the chicks. Low pathogenic avian influenza (LPAI) showed a low positive rate of antibody compared with those of Newcastle disease, indicating that domestic vaccination against LPAI was not sufficient. The antibody profile of infectious bronchitis (IB) depicted high level of titer and a low tendency of CV as compared to the uninfected control flocks, which indicated that most layer farms have been exposed to the field IB virus. In case of avian metapneumovirus infection (aMPV) and Mycoplasma synoviae (MS), since the introduction of the vaccine in 2011 and 2017, respectively, the positive rate and the titer level were higher than those in pevious times. No significant difference in the changes of seasonal result was observed, indicating proper vaccination and improvement in biosecurity and management.