Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0149514 (bronchitis)
 6,902 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The specific lacrimal fluid IgA levels and the specific serum IgG levels of broiler chicks (meat type hybrids (MT)), brown-egg layer chicks (heavy layer (HL)), and white leghorn chicks (light layer (LL)) were compared after infectious bronchitis virus (IBV) ocular vaccination at 1 day of age. All birds were maintained as a mixed population throughout the experiment of 45 days. The class specific antibody levels were determined at regular intervals by enzyme-linked immunosorbent assays. All birds responded to the vaccination stimulus as shown by a significant increase of antibody levels in both serum and lacrimal fluid. When comparing the IgG response of the chicken lines tested, LL chicks showed higher serum IBV-IgG values at the time of maximal response at days 5 and 9 post-vaccination (pv). This bird group also showed a more homogeneous (lowest coefficient of variation of values) serum IgG response. On day 13 pv and until the last serum sampling day (day 41 pv) all three chicken types showed statistically identical serum IBV-IgG levels. The local IgA response detected in lacrimal fluids showed differences between the chicks at the time of maximal levels (days 5 to 14 pv), the response of LL chicks being the highest. LL chicks maintained higher specific IgA levels than MT and HL chicks almost throughout the experimental period. According to the coefficient of variation of the absorbance values (36%), the IgA response shown by LL chicks was the most homogeneous.
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PMID:Local and systemic specific antibody response of different chicken lines after ocular vaccination against infectious bronchitis. 892 32

We evaluated the association between antibody (Ab) production and disease resistance. A controlled-challenge protocol was developed to mimic natural infection and to yield a higher rate of mortality following Escherichia coli (EC) challenge. Chicks were first infected with infectious bronchitis virus (IBV) by injecting a high dose of vaccine (attenuated virus) into their air sacs and then were infected with pathogenic EC introduced intratracheally. The experimental population consisted of lines divergently selected for high (HH) or low (LL) Ab response to EC vaccination, an HH x LL cross (HL), and commercial broilers (CC). When chicks were vaccinated with EC vaccine, mean Ab titer 15 d post-EC challenge was threefold higher in HH than LL lines, but both lines exhibited very low mortality (approximately 2%). When chicks were not vaccinated prior to EC challenge, high mortality (8 to 20%) occurred in the slow-growing HH, LL, and HL lines, and much higher mortality (approximately 40%) occurred among the CC broilers that were 38% heavier than the HH, LL, and HL lines. Mean level of Ab to EC, 7 d after EC challenge, was about twofold higher in HH vs. LL chicks and intermediate in HL and CC chicks. Within each line, Ab levels were higher in chicks exhibiting colibacillosis than in healthy ones, suggesting that these Ab were produced as a result of ongoing infection but were too late to fully prevent morbidity and mortality. These results indicate that rapid growth rate substantially reduces broiler viability, whereas Ab levels produced in response to acute pathogenic challenge without prior vaccination do not contribute to disease resistance. Among the relatively slow-growing lines, mortality was about twofold higher in HH than in LL lines. This finding may confirm previous reports that without prior vaccination, high Ab response to acute challenge increases consequent mortality; alternatively, the LL line may be superior in nonspecific defense mechanisms.
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PMID:Antibody responses and morbidity following infection with infectious bronchitis virus and challenge with Escherichia coli, in lines divergently selected on antibody response. 1187 23

The MHC genes have a profound effect on animal abilities to respond to specific antigens because they play a role in presenting foreign antigens to T cells during the course of the humoral or cellular immune response. In the current study, polymorphism in the MHC class I alpha2 domain was compared in 2 lines divergently selected for high (HH) or low (LL) antibody response to Escherichia coli vaccine. These lines also differ markedly in their antibody response to natural E. coli exposure and to vaccination with Newcastle disease virus, infectious bronchitis virus, and infectious bursa disease virus. Recent trials have shown that the LL chicks exhibit a significantly higher percentage of CD8+ T lymphocytes in their peripheral blood lymphocytes and spleen than HH chicks. Despite symmetrical selection intensity in both lines, polymorphism of the alpha2-domain gene was higher in the LL line than in the HH line. Among 29 single-nucleotide polymorphism positions found, 3 were unique to the HH line, 15 were unique to the LL line, and 11 were polymorphic in both lines. These single nucleotide polymorphism positions were not 100% line specific and were in agreement with the genetic variation in antibody level or cellular response still found within the selection lines. Five amino acid positions showed significant differences in polymorphism between the selection lines. These were located within the antigen-binding cleft, suggesting that these positions might influence the ability of MHC class I to bind foreign antigens and leading to differences in immunocompetence between the lines.
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PMID:Genetic variation in major histocompatibility complex class I alpha2 gene among broilers divergently selected for high or low early antibody response to Escherichia coli. 1615 3