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Research Note: Physiological Effects of Adrenocorticotropic Hormone and Hydrocortisone in Laying Hens1
Research Note: Physiological Effects of Adrenocorticotropic Hormone and Hydrocortisone in Laying Hens 1 H. G. GRAY, T. J. PARADIS, and P. W. CHANG Department of Fisheries, Animal and Veterinary Science, University of Rhode. Island, Kingston, Rhode Island 02881 (Received for publication July 29, 1988)
1989 Poultry Science 68:1710-1713 INTRODUCTION
MATERIALS AND METHODS
Environmental stressors in poultry have been clearly identified, and their effects have been reported by numerous investigators (Siegel, 1980; Edens, 1983; Freeman, 1985, 1987). In poultry production systems, however, the level of stress induced by inherent stressors has been difficult to quantify. Hill (1983) presented a general review of stress indicators in poultry. Studies on the physiological effects of stress have generally focused on changes in the adrenal and circulating levels of adrenocorticotropic hormones (ACTH) and corticosteroids (Siegel, 1971; Freeman, 1985) or on immunological responses (Siegel, 1985), including the regression of lymphoid tissues (Garren and Shaffher, 1956; Newcomer and Connally, 1960) and changes in the cellular components of blood (Gross and Siegel, 1983). The present experiment involved die administration of ACTH and hydrocortisone to layers in order to induce physiological changes similar to those of chronic stress, thus allowing these alterations to be studied as indicators of stress.
Husbandry. Thirty-six White Leghorn hens (Shaver strain) were obtained from a commercial poultry flock. The birds were housed singly in cages with a floor area of .13 m2 and a volume of .054 m3. Feed (16.1% CP and 2,860 kcal ME/kg feed) and water were available on an ad libitum basis in troughs. The environment was controlled with ambient temperatures of 16 to 18 C and a regimen of 14:10 h of light:dark. The birds were conditioned by handling during a 2-wk period before the experiment Experimental Design. Individual birds aged 7 to 8 mo were randomly assigned to treatment groups and received one of the following daily hormone (Sigma Chemical Co., St. Louis, MO) injections: .2 mL of a sesame-oil vehicle; 6.3 IU of ACTH/kg; 20.0 IU of ACTH/kg; .25 mg of hydrocortisone/kg; or 2.5 mg of hydrocortisone/kg of live weight. The appropriate daily dosage of a hormone or the control solution was given by a single, intramuscular injection on Days 0, 1, 2, and 3. Blood was collected on Days 1, 2, 3 and 4. Hematological Data. Blood was collected without an anticoagulant from the brachial vein. Total leucocyte counts were obtained from a hemocytometer, using the modified Rees-Ecker method described by Lucas and Jamroz (1961). Blood smears were made by
'Contribution Number 2432, Rhode Island Agricultural Experiment Station, University of Rhode Island, Kingston, RI 02881
1710
Downloaded from http://ps.oxfordjournals.org/ at Albert R. Mann Library on November 19, 2014
ABSTRACT To study the hormonal effects on hematologic parameters as indicators of chronic stress, exogenous adrenocorticotropin (ACTH) at 6.3 or 20.0 IU/kg/day and hydrocortisone at .25 or 2.5 mg/kg/day were administered parenterally to laying hens. Both ACTH treatments induced significant (P<.05) heterophilia, monocytosis, eosinophilia, and basophilia. Significantly elevated leucocyte counts and lymphopenia (P<.05) were observed with the high dosage of ACTH. Both hydrocortisone-treated groups developed an absolute lymphopenia and heterophilia (P<.05). The low dosage of hydrocortisone induced a significant (P<05) monocytosis; the high dosage caused significant (P<.05) decreases in the total eosinophil and basophil counts as well as an increase in the ratio of heterophils to lymphocytes. The hemopoietic parameters, especially heterophil counts, were sensitive indicators of a hormonal stress response induced by the administration of ACTH and hydrocortisone. (Key words: adrenocorticotropin, hydrocortisone, stress, differential leucocyte counts)
1711
RESEARCH NOTE TABLE 1. Effect (x ± SE) of adrenocorticotropic hormone (ACTH) and hydrocortisone on total leucocyte, lymphocyte, monocyte, eosinophil, and basophil counts Treatment group1
N2
Leucocytes
1 2 3 4 5
12 6 6 6 6
20,680 25,450 22,896 22,454 21,159
Lymphocytes
± 606 b ± 942" ± 699* ± 754* ± 2,0O8b
14,376 15,073 13,472 11,901 3308
± ± ± ± ±
Monocytes
430 ab 641 a 516 b 490= 311 d
1,014 1,582 1,371 1,508 1,175
± ± ± ± ±
Eosinophils
54 c 83 a 84 a b 122a HO1*
245 500 452 251 73
± ± ± ± ±
Basophils
30b 59a 75 a 35 b 17c
466 685 687 560 164
± ± ± ± ±
37 b 44 a 61 a 59 ab 39 c
a_d
the glass-slide method, then dried, and stained immediately with May-Grunwald and Giemsa staining solutions (Lucas and Jamroz, 1961). Differential leucocyte counts were made directly by microscopic examination. The heterophil:lymphocyte (H:L) ratios were determined by dividing the relative number of heterophils by the relative number of lymphocytes. Statistical Analysis. The data were analyzed by ANOVA (Steel and Torrie, 1960) using a General Linear Model program from the Statistical Analysis System (SAS Institute, 1985). Main effects by treatment and day and treatment-by-day interactions were considered as fixed. Replications were considered to be random. Duncan's multiple range test was used to separate the means for hormone treatments (Duncan, 1955). RESULTS AND DISCUSSION
Hematological Studies. The mean values pooled over days for total leucocyte, lympho-
cyte, monocyte, eosinophil, and basophil counts are presented in Table 1, since day effects and treatment-by-day interactions were nonsignificant. Leucocytosis (P<.05) occurred in birds treated with the low dose of ACTH, compared to the controls and the high dose of hydrocortisone. In earlier studies, a leucopenia developed in hens after injections with adrenal cortical extracts (Shapiro and Schechtman, 1949) and in chicks after treatments with ACTH and Cortisol (Siegel, 1968). Other researchers (Newcomer, 1957; Glick, 1961; Rusu and Cooper, 1975) induced leucocytosis in chickens by administering ACTH and glucocorticoids. The heterophil counts (Table 2) and H:L ratios (Table 3) are given by days because the treatment-by-day interactions were significant (P<.05). Significant heterophilias (P<.05) were observed with ACTH and hydrocortisone injections at all dosage levels, compared to the control group. An absolute lymphopenia
TABLE 2. Effect (x ± SE) of adrenocorticotropic hormone (ACTH) and hydrocortisone on total heterophil counts, by days Treatment group1 1 2 3 4 5
N2 12 6 6 6 6
Day 1 4,335 6,205 6^85 9,165 19,875
± 489 ± 730 ± 978 ± 648 ± 3,523
Day 2
Day 3
Day 4
4,284 6,771 7,078 6,507 12,509
(cclIs/mm3) 418 4,508 1344 8,673 417 6,754 712 8,721 3,827 20,784
— — — ± 365 5,197 ± 1,528 8,785 ± 453 7,241 ± 1,069 8,476 ± 3,748 11,795
± ± ± ± ±
± ± ± ± ±
1,037 1,323 469 1,008 2,385
•Group 1 = controls', Group 2 = 6.3 IU of ACTH/kg/day; Group 3 : 20.0 IU of ACTH/kg/day; Group 4 = .25 mg of hydrocortisone/kg/day; Group 5 = 2.5 mg of hydrocortisone/kg/day. 2 Birds sampled on Days 1, 2, 3, and 4.
Downloaded from http://ps.oxfordjournals.org/ at Albert R. Mann Library on November 19, 2014
Means within a column with no common superscripts are significantly different (P<.05). •Group 1 = controls; Group 2 = 6.3 IU of ACTH/kg/day; Group 3 = 20.0 IU of ACTH/kg/day; Group 4 = .25 mg of hydrocortisone/kg/day; Group 5 = 2.5 mg of hydrocortisone/kg/day. Birds sampled on Days 1, 2, 3, and 4.
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GRAY ET AL. TABLE 3. Effect (x ± SE) of adrenocorticotropic hormone (ACTH) and hydrocortisone on heterophil!lymphocyte ratios, by days
Treatment group1
N2
Day 1
1 2 3 4 5
12 6 6 6 6
.31 .42 .47 .86 5.95
± ± ± ± ±
.04 .05 .08 .08 .65
Day 2
Day 3
Day 4
.31 .51 .61 .55 5.49
.33 .61 .53 .78 5.74
.37 .58 .51 .69 3.03
± .04 ± .14 ± .05 ± .08 ± 1.46
± .03 ± .09 ± .05 ± .12 ±1.19
± ± ± ± ±
.07 .11 .04 .08 .66
'Group 1 = controls; Group 2 = 6.3 IU of ACTH/kg/day; Group 3 = 20.0 IU of ACTH/kg/day; Group 4 = .25 mg of hydrocortisone/kg/day; Group 5 = 2.5 mg of hydrocortisone/kg/day. 2 Birds sampled on Days 1, 2, 3, and 4. Downloaded from http://ps.oxfordjournals.org/ at Albert R. Mann Library on November 19, 2014
(P<.05) occurred only in the hydrocortisone- cortisone. These results support the data of Newcomer (1957), who attributed the inconsistreated birds (Table 1). Several investigators have found that exoge- tent changes to low cell numbers found in the nous ACTH and glucocorticoids will induce systemic circulation. The present study suggests that absolute heterophilia and lymphopenia in domestic fowl (Shapiro and Schechtman, 1949; Newcomer, heterophil counts are the most sensitive hema1958; Siegel, 1968; Gross et al., 1980). Other topoietic indicators of chronic stress. Total researchers (Huble, 1955; Newcomer, 1957; monocyte and lymphocyte counts and H:L Glick, 1961; Rusu and Cooper, 1975) have ratios do indicate a response to hormonal reported a substantial heterophilia with no stress, but are less sensitive and less concluchange in lymphocyte counts after administer- sive. The leucocyte, basophil, and eosinophil ing ACTH or cortisone acetate, or both. Thus, counts were inconsistent and were unreliable absolute heterophil counts appear to be very indicators of a stress response. sensitive to changes in the circulating levels of the corticosteroids; lymphocyte numbers reREFERENCES spond to a lesser extent. An increase in the H:L ratios (P<05) was Duncan, D. B., 1955. Multiple range and multiple F tests. Biometrics 11:1-42. observed only in the hens treated with 2.5 mg Edens, F. W., 1983. Effect of environmental stressors on of hydrocortisone per kg of BW. The increase male reproduction. Poultry Sci. 62:1676-1689. was observed on all 4 days (Table 3). The H:L Freeman, B. ML 1985. Stress and the domestic fowl: physiological fact or fantasy. World's Poult. Sci. J. 41:45-51. ratio ranged from .31 to .37 in the control Freeman, B. M., 1987. The stress syndrome. World's Poult. group and from 3.03 to 5.95 in the group Sci. J. 43:15-19. treated with 2.5 mg of hydrocortisone. These Garren, H. W., and C. S. Shaffher, 1956. How the period of results suggest that changes in the H:L ratio exposure to different stress stimuli affects the endocrine and lymphatic gland weights of young chickens. are less sensitive than the heterophil counts to Poultry Sci. 35:266-272. the hormones administered. Glick, B., 1961. The effect of bovine growth hormone, A monocytosis was observed in the hens deoxycorticosterone acetate, and cortisone acetate on receiving ACTH and hydrocortisone (Table 1). the white blood cell counts of 2-week-old chickens. Poultry Sci. 40:1537-1539. These differences were significant (P<.05) for all hormone treatments, compared to controls, Gross, W. B., and H. S. Siegel, 1983. Evaluation of the heteropnil/lymphocyte ratio as a measure of stress in except for the group receiving 2.5 of mg chickens. Avian Dis. 27:972-979. hydrocortisone per kg of live weight. Gross, W. B., P. B. Siegel, and R. T. DuBose, 1980. Some effects of feeding corticosterone to chickens. Poultry Data on the total number of eosinophils and Sci. 59:516-522. basophils indicated that the hormone treatHill, J. A., 1983. Indicators of stress in poultry. World's ments elicited a varied response in these types Poult. Sci. J. 39:24-32. of cells (Table 1). The circulating levels of Huble, J., 1955. Hematological changes in cockerels after ACTH and cortisone-acetate treatment. Poultry Sci. both cell types increased (P<.05) in the groups 34:1357-1359. treated with low and high amounts of ACTH, A. M., and C. Jamroz, 1961. Atlas of Avian Hematolbut the reverse response (P<.05) was obtained Lucas,ogy. Agriculture Monograph 25, USDA, Washington, with the group that received a high amount of DC.
RESEARCH NOTE Newcomer, W. S., 1957. Blood cell changes following ACTH injection in the chick. Proc. Soc. Exp. Biol. Med. 96:613-616. Newcomer, W. S., 1958. Physiologic factors that influence acidophilia induced by stressors in the chicken. Am. J. Physiol. 194:251-254. Newcomer, W. S., and J. D. Connally, 1960. The bursa of fabricius as an indicator of chronic stress in immature chickens. Endocrinology 67:264-266. Rusu, V. M., and M. D. Cooper, 1975. In vivo effects of cortisone on the B cell line in chickens. J. Immunol. 115:1370-1374. SAS Insntute, 1985. SAS User's Guide: Statistics, Version 5.18. SAS InsL Inc., Cary, NC. Shapiro, A. B., and A. M. Schechtman, 1949. Effect of
1713
adrenal cortical extract on the blood picture and serum proteins of fowl. Proc. Soc. Exp. Biol. Med. 70: 440-445. Siegel, H. S., 1968. Blood cells and chemistry of young chickens during daily ACTH and Cortisol administration. Poultry Sci. 47:1811-1817. Siegel, H. S., 1971. Adrenals, stress and the environment. World's Poult. Sci. J. 27:327-349. Siegel, H. S., 1980. Physiological stress in birds. Bioscience 30:529-534. Siegel, H. S., 1985. Immunological responses as indicators of stress. World's Poult. Sci. J. 41:36-44. Steel, R.G.D., and J. H. Tcrrie, 1960. Principles and Procedures of Statistics. McGraw-Hill Book Co., Inc., New York, NY. Downloaded from http://ps.oxfordjournals.org/ at Albert R. Mann Library on November 19, 2014
1989 Poultry Science 68:1710-1713 INTRODUCTION
MATERIALS AND METHODS
Environmental stressors in poultry have been clearly identified, and their effects have been reported by numerous investigators (Siegel, 1980; Edens, 1983; Freeman, 1985, 1987). In poultry production systems, however, the level of stress induced by inherent stressors has been difficult to quantify. Hill (1983) presented a general review of stress indicators in poultry. Studies on the physiological effects of stress have generally focused on changes in the adrenal and circulating levels of adrenocorticotropic hormones (ACTH) and corticosteroids (Siegel, 1971; Freeman, 1985) or on immunological responses (Siegel, 1985), including the regression of lymphoid tissues (Garren and Shaffher, 1956; Newcomer and Connally, 1960) and changes in the cellular components of blood (Gross and Siegel, 1983). The present experiment involved die administration of ACTH and hydrocortisone to layers in order to induce physiological changes similar to those of chronic stress, thus allowing these alterations to be studied as indicators of stress.
Husbandry. Thirty-six White Leghorn hens (Shaver strain) were obtained from a commercial poultry flock. The birds were housed singly in cages with a floor area of .13 m2 and a volume of .054 m3. Feed (16.1% CP and 2,860 kcal ME/kg feed) and water were available on an ad libitum basis in troughs. The environment was controlled with ambient temperatures of 16 to 18 C and a regimen of 14:10 h of light:dark. The birds were conditioned by handling during a 2-wk period before the experiment Experimental Design. Individual birds aged 7 to 8 mo were randomly assigned to treatment groups and received one of the following daily hormone (Sigma Chemical Co., St. Louis, MO) injections: .2 mL of a sesame-oil vehicle; 6.3 IU of ACTH/kg; 20.0 IU of ACTH/kg; .25 mg of hydrocortisone/kg; or 2.5 mg of hydrocortisone/kg of live weight. The appropriate daily dosage of a hormone or the control solution was given by a single, intramuscular injection on Days 0, 1, 2, and 3. Blood was collected on Days 1, 2, 3 and 4. Hematological Data. Blood was collected without an anticoagulant from the brachial vein. Total leucocyte counts were obtained from a hemocytometer, using the modified Rees-Ecker method described by Lucas and Jamroz (1961). Blood smears were made by
'Contribution Number 2432, Rhode Island Agricultural Experiment Station, University of Rhode Island, Kingston, RI 02881
1710
Downloaded from http://ps.oxfordjournals.org/ at Albert R. Mann Library on November 19, 2014
ABSTRACT To study the hormonal effects on hematologic parameters as indicators of chronic stress, exogenous adrenocorticotropin (ACTH) at 6.3 or 20.0 IU/kg/day and hydrocortisone at .25 or 2.5 mg/kg/day were administered parenterally to laying hens. Both ACTH treatments induced significant (P<.05) heterophilia, monocytosis, eosinophilia, and basophilia. Significantly elevated leucocyte counts and lymphopenia (P<.05) were observed with the high dosage of ACTH. Both hydrocortisone-treated groups developed an absolute lymphopenia and heterophilia (P<.05). The low dosage of hydrocortisone induced a significant (P<05) monocytosis; the high dosage caused significant (P<.05) decreases in the total eosinophil and basophil counts as well as an increase in the ratio of heterophils to lymphocytes. The hemopoietic parameters, especially heterophil counts, were sensitive indicators of a hormonal stress response induced by the administration of ACTH and hydrocortisone. (Key words: adrenocorticotropin, hydrocortisone, stress, differential leucocyte counts)
1711
RESEARCH NOTE TABLE 1. Effect (x ± SE) of adrenocorticotropic hormone (ACTH) and hydrocortisone on total leucocyte, lymphocyte, monocyte, eosinophil, and basophil counts Treatment group1
N2
Leucocytes
1 2 3 4 5
12 6 6 6 6
20,680 25,450 22,896 22,454 21,159
Lymphocytes
± 606 b ± 942" ± 699* ± 754* ± 2,0O8b
14,376 15,073 13,472 11,901 3308
± ± ± ± ±
Monocytes
430 ab 641 a 516 b 490= 311 d
1,014 1,582 1,371 1,508 1,175
± ± ± ± ±
Eosinophils
54 c 83 a 84 a b 122a HO1*
245 500 452 251 73
± ± ± ± ±
Basophils
30b 59a 75 a 35 b 17c
466 685 687 560 164
± ± ± ± ±
37 b 44 a 61 a 59 ab 39 c
a_d
the glass-slide method, then dried, and stained immediately with May-Grunwald and Giemsa staining solutions (Lucas and Jamroz, 1961). Differential leucocyte counts were made directly by microscopic examination. The heterophil:lymphocyte (H:L) ratios were determined by dividing the relative number of heterophils by the relative number of lymphocytes. Statistical Analysis. The data were analyzed by ANOVA (Steel and Torrie, 1960) using a General Linear Model program from the Statistical Analysis System (SAS Institute, 1985). Main effects by treatment and day and treatment-by-day interactions were considered as fixed. Replications were considered to be random. Duncan's multiple range test was used to separate the means for hormone treatments (Duncan, 1955). RESULTS AND DISCUSSION
Hematological Studies. The mean values pooled over days for total leucocyte, lympho-
cyte, monocyte, eosinophil, and basophil counts are presented in Table 1, since day effects and treatment-by-day interactions were nonsignificant. Leucocytosis (P<.05) occurred in birds treated with the low dose of ACTH, compared to the controls and the high dose of hydrocortisone. In earlier studies, a leucopenia developed in hens after injections with adrenal cortical extracts (Shapiro and Schechtman, 1949) and in chicks after treatments with ACTH and Cortisol (Siegel, 1968). Other researchers (Newcomer, 1957; Glick, 1961; Rusu and Cooper, 1975) induced leucocytosis in chickens by administering ACTH and glucocorticoids. The heterophil counts (Table 2) and H:L ratios (Table 3) are given by days because the treatment-by-day interactions were significant (P<.05). Significant heterophilias (P<.05) were observed with ACTH and hydrocortisone injections at all dosage levels, compared to the control group. An absolute lymphopenia
TABLE 2. Effect (x ± SE) of adrenocorticotropic hormone (ACTH) and hydrocortisone on total heterophil counts, by days Treatment group1 1 2 3 4 5
N2 12 6 6 6 6
Day 1 4,335 6,205 6^85 9,165 19,875
± 489 ± 730 ± 978 ± 648 ± 3,523
Day 2
Day 3
Day 4
4,284 6,771 7,078 6,507 12,509
(cclIs/mm3) 418 4,508 1344 8,673 417 6,754 712 8,721 3,827 20,784
— — — ± 365 5,197 ± 1,528 8,785 ± 453 7,241 ± 1,069 8,476 ± 3,748 11,795
± ± ± ± ±
± ± ± ± ±
1,037 1,323 469 1,008 2,385
•Group 1 = controls', Group 2 = 6.3 IU of ACTH/kg/day; Group 3 : 20.0 IU of ACTH/kg/day; Group 4 = .25 mg of hydrocortisone/kg/day; Group 5 = 2.5 mg of hydrocortisone/kg/day. 2 Birds sampled on Days 1, 2, 3, and 4.
Downloaded from http://ps.oxfordjournals.org/ at Albert R. Mann Library on November 19, 2014
Means within a column with no common superscripts are significantly different (P<.05). •Group 1 = controls; Group 2 = 6.3 IU of ACTH/kg/day; Group 3 = 20.0 IU of ACTH/kg/day; Group 4 = .25 mg of hydrocortisone/kg/day; Group 5 = 2.5 mg of hydrocortisone/kg/day. Birds sampled on Days 1, 2, 3, and 4.
1712
GRAY ET AL. TABLE 3. Effect (x ± SE) of adrenocorticotropic hormone (ACTH) and hydrocortisone on heterophil!lymphocyte ratios, by days
Treatment group1
N2
Day 1
1 2 3 4 5
12 6 6 6 6
.31 .42 .47 .86 5.95
± ± ± ± ±
.04 .05 .08 .08 .65
Day 2
Day 3
Day 4
.31 .51 .61 .55 5.49
.33 .61 .53 .78 5.74
.37 .58 .51 .69 3.03
± .04 ± .14 ± .05 ± .08 ± 1.46
± .03 ± .09 ± .05 ± .12 ±1.19
± ± ± ± ±
.07 .11 .04 .08 .66
'Group 1 = controls; Group 2 = 6.3 IU of ACTH/kg/day; Group 3 = 20.0 IU of ACTH/kg/day; Group 4 = .25 mg of hydrocortisone/kg/day; Group 5 = 2.5 mg of hydrocortisone/kg/day. 2 Birds sampled on Days 1, 2, 3, and 4. Downloaded from http://ps.oxfordjournals.org/ at Albert R. Mann Library on November 19, 2014
(P<.05) occurred only in the hydrocortisone- cortisone. These results support the data of Newcomer (1957), who attributed the inconsistreated birds (Table 1). Several investigators have found that exoge- tent changes to low cell numbers found in the nous ACTH and glucocorticoids will induce systemic circulation. The present study suggests that absolute heterophilia and lymphopenia in domestic fowl (Shapiro and Schechtman, 1949; Newcomer, heterophil counts are the most sensitive hema1958; Siegel, 1968; Gross et al., 1980). Other topoietic indicators of chronic stress. Total researchers (Huble, 1955; Newcomer, 1957; monocyte and lymphocyte counts and H:L Glick, 1961; Rusu and Cooper, 1975) have ratios do indicate a response to hormonal reported a substantial heterophilia with no stress, but are less sensitive and less concluchange in lymphocyte counts after administer- sive. The leucocyte, basophil, and eosinophil ing ACTH or cortisone acetate, or both. Thus, counts were inconsistent and were unreliable absolute heterophil counts appear to be very indicators of a stress response. sensitive to changes in the circulating levels of the corticosteroids; lymphocyte numbers reREFERENCES spond to a lesser extent. An increase in the H:L ratios (P<05) was Duncan, D. B., 1955. Multiple range and multiple F tests. Biometrics 11:1-42. observed only in the hens treated with 2.5 mg Edens, F. W., 1983. Effect of environmental stressors on of hydrocortisone per kg of BW. The increase male reproduction. Poultry Sci. 62:1676-1689. was observed on all 4 days (Table 3). The H:L Freeman, B. ML 1985. Stress and the domestic fowl: physiological fact or fantasy. World's Poult. Sci. J. 41:45-51. ratio ranged from .31 to .37 in the control Freeman, B. M., 1987. The stress syndrome. World's Poult. group and from 3.03 to 5.95 in the group Sci. J. 43:15-19. treated with 2.5 mg of hydrocortisone. These Garren, H. W., and C. S. Shaffher, 1956. How the period of results suggest that changes in the H:L ratio exposure to different stress stimuli affects the endocrine and lymphatic gland weights of young chickens. are less sensitive than the heterophil counts to Poultry Sci. 35:266-272. the hormones administered. Glick, B., 1961. The effect of bovine growth hormone, A monocytosis was observed in the hens deoxycorticosterone acetate, and cortisone acetate on receiving ACTH and hydrocortisone (Table 1). the white blood cell counts of 2-week-old chickens. Poultry Sci. 40:1537-1539. These differences were significant (P<.05) for all hormone treatments, compared to controls, Gross, W. B., and H. S. Siegel, 1983. Evaluation of the heteropnil/lymphocyte ratio as a measure of stress in except for the group receiving 2.5 of mg chickens. Avian Dis. 27:972-979. hydrocortisone per kg of live weight. Gross, W. B., P. B. Siegel, and R. T. DuBose, 1980. Some effects of feeding corticosterone to chickens. Poultry Data on the total number of eosinophils and Sci. 59:516-522. basophils indicated that the hormone treatHill, J. A., 1983. Indicators of stress in poultry. World's ments elicited a varied response in these types Poult. Sci. J. 39:24-32. of cells (Table 1). The circulating levels of Huble, J., 1955. Hematological changes in cockerels after ACTH and cortisone-acetate treatment. Poultry Sci. both cell types increased (P<.05) in the groups 34:1357-1359. treated with low and high amounts of ACTH, A. M., and C. Jamroz, 1961. Atlas of Avian Hematolbut the reverse response (P<.05) was obtained Lucas,ogy. Agriculture Monograph 25, USDA, Washington, with the group that received a high amount of DC.
RESEARCH NOTE Newcomer, W. S., 1957. Blood cell changes following ACTH injection in the chick. Proc. Soc. Exp. Biol. Med. 96:613-616. Newcomer, W. S., 1958. Physiologic factors that influence acidophilia induced by stressors in the chicken. Am. J. Physiol. 194:251-254. Newcomer, W. S., and J. D. Connally, 1960. The bursa of fabricius as an indicator of chronic stress in immature chickens. Endocrinology 67:264-266. Rusu, V. M., and M. D. Cooper, 1975. In vivo effects of cortisone on the B cell line in chickens. J. Immunol. 115:1370-1374. SAS Insntute, 1985. SAS User's Guide: Statistics, Version 5.18. SAS InsL Inc., Cary, NC. Shapiro, A. B., and A. M. Schechtman, 1949. Effect of
1713
adrenal cortical extract on the blood picture and serum proteins of fowl. Proc. Soc. Exp. Biol. Med. 70: 440-445. Siegel, H. S., 1968. Blood cells and chemistry of young chickens during daily ACTH and Cortisol administration. Poultry Sci. 47:1811-1817. Siegel, H. S., 1971. Adrenals, stress and the environment. World's Poult. Sci. J. 27:327-349. Siegel, H. S., 1980. Physiological stress in birds. Bioscience 30:529-534. Siegel, H. S., 1985. Immunological responses as indicators of stress. World's Poult. Sci. J. 41:36-44. Steel, R.G.D., and J. H. Tcrrie, 1960. Principles and Procedures of Statistics. McGraw-Hill Book Co., Inc., New York, NY. Downloaded from http://ps.oxfordjournals.org/ at Albert R. Mann Library on November 19, 2014