Effects of Stress on the Corticosterone Content of the Blood Plasma and Adrenal Gland of Intact and Bursectomized Gallus Domesticus

1. Experiments were conducted to determine whether different handling methods and crating periods differentially affect plasma corticosterone (CS) concentrations in 6 to 7-week-old broilers. 2. Broilers were subjected to 1 of 3 handling methods for 2 min: (i) 3 birds held in an inverted position in one hand (multiple inverted, MI), (ii) 1 bird held in an inverted position (single inverted, SI), or (iii) upright handling (U), which consisted of holding a bird gently with both hands in an upright position. 3. In experiment 1 birds were returned to their respective pens after handling and in experiment 2 they were crated for up to 4 h after the imposition of handling. In experiment 2 food deprived (FD) and fully fed (FF) uncrated birds were also sampled as controls. Blood samples were collected immediately after handling and at 1-h intervals after handling or handling and crating. 4. In experiment 1, MI and SI birds had higher CS concentrations than U birds. 5. In experiment 2, there were no significant differences in CS concentrations of crated birds despite the different handling treatments. FD birds had higher mean CS concentrations than FF birds, although not as high as those of crated birds. CS concentrations peaked at 3 h after crating. Birds showed predominantly resting behaviour after crating. 6. These results suggest that handling stress can be reduced in broilers by the use of upright handling. However, the methods of handling is not important in influencing CS concentrations if the birds are crated after handling, either because crating is a more potent stressor than handling or due to stressor additivity.

Section: Discussionmentioning

confidence: 70%

“…Fasting reduces faecal contamination of carcases (Wabeck, 1972), reduces problems resulting from heat stress (McCormick et al, 1979), and combats respiratory alkalosis-related mortality (Leeson, 1986). However, deprivation of food is considered to be a stressor in poultry (Nir et al, 1975;Scanes et al, 1980;Mench, 1991).…”

Section: Introductionmentioning

confidence: 97%

Influence of different handling methods and crating periods on plasma corticosterone concentrations in broilers

Kannan

Mench

1996

“…ACTH administration reliably increases plasma corticosterone concentrations (Edens and Siegel, 1975;Beuving and Vonder, 1986). Fasting is a potent stressor in chicks (Nir et al, 1975;Constantin et al, 1977;Freeman et al, 1980) and there is now a growing body of evidence that plasma corticosterone concentrations were also increased in older birds (from 8 weeks old to adults) by the withdrawal of food (Scanes et al, 1980;Freeman et al, 1983;Harvey et al, 1983;M. Mitchell, personal communication).…”

Section: Introductionmentioning

confidence: 93%

Adrenocortical and heterophil/lymphocyte responses to challenge in hens showing short or long tonic immobility reactions

Beuving¹,

Jones

Blokhuis³

1989

1. Adult White Leghorn hens showing short or long tonic immobility reactions were classified as low-fear (LF) or high-fear (HF) responders, respectively. Following cannulation, their adrenocortical responsiveness to ACTH administration and the effects of chronic frustration induced by thwarting of feeding on plasma corticosterone concentrations and heterophil/lymphocyte (H/L) ratios were measured at regular intervals. 2. ACTH injection elicited significant and similar mean increases in circulating corticosterone concentrations in both the LF and HF groups. 3. Absolute H/L ratios were higher in HF than in LF hens after cannulation, although both groups showed similar proportional increases from pre-operation ratios. 4. Plasma corticosterone concentrations and H/L ratios were significantly increased at 20 h and 44 h respectively after the frustration of feeding regime began. Thus, adrenocortical activation preceded increases in H/L ratios but, whereas the elevated plasma corticosterone concentrations found after 20 h remained virtually constant thereafter, H/L ratios rose progressively throughout the 68 h frustration period. 5. There were no significant differences between groups in their plasma corticosterone and H/L responses to frustration. However, a consistent trend towards greater adrenocortical activation was observed in the HF than in the LF hens.

“…Food restriction elicited alteration in both leucocytic count (Gross and Siegel, 1986;Katanbaf et al, 1989;Maxwell et al, 1992;Zulkifli et al, 1993) and steroidal hormone status (Nir et al, 1975;Freeman et al, 1981;Mench, 1992). Fasting-induced increases in corticosterone may be essential for stimulating gluconeogenesis.…”

Section: Discussionmentioning

confidence: 97%

Food restriction early or later in life and its effect on adaptability, disease resistance, and immunocompetence of heat‐stressed dwarf and nondwarf chickens

Zulkifli

Dunnington

Gross

et al. 1994

1. Dwarf and nondwarf chickens placed under 60% food restriction from either 4 to 6 (early) or 24 to 26 (late) days of age were exposed to high ambient temperatures (35 +/- 2 degrees C) from 36 to 43 d of age. 2. As measured by heterophil/lymphocyte (H/L) ratios, stress response to food restriction was similar at both ages for dwarfs while less at the younger than the older age for nondwarfs, resulting in a significant food restriction interaction of genotype by age. 3. Nondwarf chickens food restricted at the younger age had smaller increases in H/L ratios, improved resistance to marble spleen disease infection and greater growth than those restricted at the older age or fed ad libitum in response to the high ambient temperatures. 4. For dwarf chickens feeding regimen had no influence on response to the environmental insults. 5. Antibody response to sheep erythrocyte antigen was not affected by genotype or feeding regimen.