title: Evaluation of vectorelectrocardiographic analysis of young broiler chickens as a predictive index for susceptibility to ascites syndrome.
abstract: Vectorelectrocardiographic (VCG) analysis was performed on 50 male broiler chicks (1 week of age) before placement in a hypobaric chamber. During 5 weeks of exposure to hypobaric hypoxia (simulated altitude of 2900 m), all recorded mortality (38%) was due to the development of ascites syndrome. There was a positive correlation (r = 0.74, P less than 0.01) between the increment in the frontal plane mean resultant vector magnitude divided by body weight (designated as the cardiac index [CI]), with the severity of right ventricular enlargement. Chicks developing ascites syndrome had a greater CI (P less than 0.05) at 1 week of age when compared with chicks that did not develop the syndrome. Therefore, the CI calculated by VCG analysis recognizes right ventricular enlargement, suggesting that a pre-hatch or early post-hatch functional cardiac stress has occurred, predisposing the 1-week-old broiler chick to ascites syndrome. Application of the CI has a physiological index may prove useful in future studies targeted for selection of ascites syndrome resistance in broiler chickens.
authors.affiliation: Department of Poultry Science, Texas A&M University System, College Station 77843.
authors.forename: T W
authors.initials: TW
authors.lastname: Odom
authors.forename: L M
authors.initials: LM
authors.lastname: Rosenbaum
authors.forename: B M
authors.initials: BM
authors.lastname: Hargis
mesh_terms: D000531:Altitude; D000818:Animals; D001201:Ascites / Q000209:etiology / Q000276:immunology / Q000401:mortality / Q000662:veterinary*; D001835:Body Weight; D006332:Cardiomegaly / Q000150:complications / Q000175:diagnosis / Q000662:veterinary; D002645:Chickens; D004198:Disease Susceptibility; D000860:Hypoxia / Q000150:complications / Q000662:veterinary*; D008297:Male; D011201:Poultry Diseases / Q000209:etiology / Q000276:immunology* / Q000401:mortality; D013577:Syndrome; D014672:Vectorcardiography / Q000662:veterinary*