title: Factors affecting chicken thrombocyte morphology and the relationship with heterophil:lymphocyte ratios.
abstract: 1. Thrombocytes were observed in a haemocytometer chamber and cells were classified into 5 morphological groups which were related to the extent of environmental stress. Thrombocyte morphology scores (TMS) were calculated for each blood sample. 2. Following exposure to social stress, chilling, or the injection of killed Escherichia coli, both TMS and heterophil:lymphocyte (H:L) ratios were increased. From maximum values 1 d after chilling H:L and TMS values returned to normal within 2 and 11 d respectively. 3. The addition of corticosterone (200 mg/kg) to the food resulted in increased H:L ratios whereas TMS were not affected. 4. The injection of an adrenal blocker, 1,1-dichloro-2,2 bis p-choro-phenyl ethane, resulted in decreased H:L values whereas TMS were not affected. 5. Resistance to E. coli challenge infection was not affected by TMS.
authors.affiliation: Department of Large Animal Clinical Sciences, Virginia Polytechnic Institute, Blacksburg 24061.
authors.forename: W B
authors.initials: WB
authors.lastname: Gross
mesh_terms: D000818:Animals; D001792:Blood Platelets / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D002645:Chickens / Q000097:blood*; D003080:Cold Temperature / Q000009:adverse effects*; D003345:Corticosterone / Q000494:pharmacology*; D004926:Escherichia coli; D006098:Granulocytes / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D006843:Hydrocarbons, Chlorinated; D007306:Insecticides / Q000494:pharmacology*; D008214:Lymphocytes / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D013312:Stress, Physiological / Q000097:blood / Q000662:veterinary*
chemical_list: D006843:Hydrocarbons, Chlorinated; D007306:Insecticides; D003345:Corticosterone