title: Purification of chicken carbonic anhydrase isozyme-III (CA-III) and its measurement in White Leghorn chickens.
abstract: BACKGROUND
  The developmental profile of chicken carbonic anhydrase-III (CA-III) blood levels has not been previously determined or reported. We isolated CA-III from chicken muscle and investigated age-related changes in the levels of CA-III in blood.
  
  
  METHODS
  CA-III was purified from chicken muscle. The levels of CA-III in plasma and erythrocytes from 278 female chickens (aged 1-93 weeks) and 68 male chickens (aged 3-59 weeks) were determined by ELISA.
  
  
  RESULTS
  The mean level of CA-III in female chicken erythrocytes (1 week old) was 4.6 μg/g of Hb, and the CA-III level did not change until 16 weeks of age. The level then increased until 63 weeks of age (11.8 μg/g of Hb), decreased to 4.7 μg/g of Hb at 73 weeks of age, and increased again until 93 weeks of age (8.6 μg/g of Hb). The mean level of CA-III in erythrocytes from male chickens (3 weeks old) was 2.4 μg/g of Hb, and this level remained steady until 59 weeks of age. The mean plasma level of CA-III in 1-week-old female chickens was 60 ng/mL, and this level was increased at 3 weeks of age (141 ng/mL) and then remained steady until 80 weeks of age (122 ng/mL). The mean plasma level of CA-III in 3-week-old male chickens was 58 ng/mL, and this level remained steady until 59 weeks of age.
  
  
  CONCLUSIONS
  We observed both developmental changes and sex differences in CA-III concentrations in White Leghorn (WL) chicken erythrocytes and plasma. Simple linear regression analysis showed a significant association between the erythrocyte CA-III level and egg-laying rate in WL-chickens 16-63 weeks of age (p < 0.01).
authors: Laboratories of Veterinary Physiology, School of Veterinary Medicine, Azabu, University, Sagamihara, Kanagawa, Japan. nishida@azabu-u.ac.jp
authors: Toshiho
authors: T
authors: Nishita
authors: Yuichiro
authors: Y
authors: Tomita
authors: Daisuke
authors: D
authors: Yorifuji
authors: Kensuke
authors: K
authors: Orito
authors: Hideharu
authors: H
authors: Ochiai
authors: Kazuyosi
authors: K
authors: Arishima
mesh_terms: D000818:Animals; D024402:Carbonic Anhydrase II / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D002645:Chickens / Q000097:blood / Q000378:metabolism / Q000502:physiology*; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D004912:Erythrocytes / Q000201:enzymology; D005260:Female; D008297:Male; D018482:Muscle, Skeletal / Q000201:enzymology; D010058:Oviposition; D012016:Reference Values
chemical_list: D024402:Carbonic Anhydrase II