These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Effect of environmental stress on the responses of ascorbic-acid-treated chickens to Escherichia coli challenge infection.
    Author: Gross WB.
    Journal: Avian Dis; 1988; 32(3):432-6. PubMed ID: 3058111.
    Abstract:
    As the stressfulness of the environment increased (measured as increasing heterophil/lymphocyte [H/L] ratios), resistance of chickens to Escherichia coli challenge infection increased. At a relatively low level of environmental stress (H/L ratio = 0.33), the incidence of severe lesions was 22% in chickens fed diets containing 330 mg of ascorbic acid (AA)/kg and 80% in undosed controls. As the level of environmental stress increased, the dose of AA required for maximum reduction of the incidence of severe lesions increased, and the difference in lesion incidence between AA-dosed and undosed chickens decreased. When environmental stress resulted in H/L ratios of 0.53 or more, AA did not ameliorate the severity of infection. At levels of stress characterized by H/L ratios between 0.39 and 0.44, increasing doses of AA resulted in increased susceptibility to E. coli until a dose associated with maximum susceptibility was reached. Further increases in the dose of AA resulted in decreased susceptibility until a dose associated with maximum resistance was reached. In chickens fed feed containing 15 mg corticosterone/kg, increasing doses of AA resulted in increasing susceptibility to E. coli.
    [Abstract] [Full Text] [Related] [New Search]