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Featured researches published by C. R. Parkhurst.


Annals of the New York Academy of Sciences | 1975

SOME EFFECTS OF EXPOSURE OF THE JAPANESE QUAIL EMBRYO TO 2.45‐GHz MICROWAVE RADIATION

Donald I. McRee; Philip E. Hamrick; Joseph Zinkl; P. Thaxton; C. R. Parkhurst

Exposure of quail eggs 4 hr per day during the first 5 incubation days at 2450 MHz and in an exposure field of 30 mW/cm-2 and at an absorbed power of 14 mW/g does not cause any great change in body weight, observed gross malformations, rbc, wbc, hematocrit, hemoglobin, or differential wbc percentages. If small differences exist in these parameters due to microwave exposure, they are obscured by the large variability between individual quail. This variability is believed to partially result from changing blood values in the developing young quail, and the 2-day spread in ages at the time of sacrifice could account for some of the variability. The overall hatch percentages for the exposed and control eggs were approximately equal. A slight significant decrease (11%) in hemoglobin was noted in the birds irradiated on Day 2. Additional verification, however, is needed, because the observed change is less than the normal range of values observed in young quail. These data do suggest, however, that exposure of developing Japanese quail embryo to microwave radiation of the frequency and power density level used in this study does not preclude normal systemic development, hematologic differentiation, or the general hardiness of the hatched quail.


Poultry Science | 2000

D-xylose absorption as a measurement of malabsorption in poult enteritis and mortality syndrome

R. E. Doerfler; L. D. Cain; F. W. Edens; C. R. Parkhurst; M. A. Qureshi; G. B. Havenstein

Abstract Severe wasting of body tissues, diarrhea, high morbidity and mortality, and stunting are all characteristics of poult enteritis and mortality syndrome (PEMS). The wasting of musculature and loss of nearly all adipose tissue suggested that even though the PEMS-infected poults were eating some feed, nutrient intake was not sufficient to meet body requirements for maintenance and growth. Because epithelial cells in the gastrointestinal tract appeared to be a target of the undefined etiological agent (or agents) that causes PEMS, a study was conducted in which PEMS-infected poults were evaluated for malabsorption through 3 wk of age. D-Xylose, a poorly metabolized pentose, was given per os as a bolus, and blood samples were obtained from the ulnar vein in the wing of control and PEMS-infected poults over a 3-h period to estimate intestinal absorption. D-Xylose absorption in control poults peaked 30 to 60 min after the oral treatment, similar to results reported earlier. The PEMS-infected poults did not show a peak in absorption. The PEMS-infected poults showed significant delays in D-xylose absorption at 4, 7, and 11 d after PEMS challenge. The severe malabsorption and metabolic deficiency problem associated with PEMS was postulated to be a direct effect of the undefined infectious agent or agents that cause the disease.


Poultry Science | 1997

Atypical Escherichia coli strains and their association with poult enteritis and mortality syndrome

F. W. Edens; C. R. Parkhurst; M. A. Qureshi; Ivan A. Casas; G. B. Havenstein

Abstract To date, no definitive etiology has been described for Poult Enteritis and Mortality Syndrome (PEMS). However, two atypical Escherichia coli colony types are isolated consistently from moribund and dead poults afflicted with PEMS. To test the infectivity of these E. coli strains, poults were placed into floor pens in three isolation treatment rooms: 1) Control: no bacterial challenge, 2) E. coli colony Types 1 or 2 posthatch oral challenge: 10(8) cfu/per poult at 1 d, and 3) E. coli colony Types 1 or 2 posthatch oral challenge: 10(8) cfu/per poult at 6 d. Daily intramuscular injections of cyclophosphamide (100 micrograms per poult) from 1 to 5 d posthatch were given to half of the poults in each treatment. Atypical E. coli challenge caused BW depression, and cyclophosphamide treatment exacerbated the response. All E. coli-challenged poults developed diarrhea similar to PEMS. Mortality was increased by both atypical E. coli colony types, but at 21 d E. coli colony Type 2 caused greater mortality than colony Type 1. With cyclophosphamide treatment, mortality was exacerbated with both colony types, but colony Type 2 at 1 d caused the greatest mortality. Ultrastructural damage to ileum epithelium cell microvilli and subcellular organelles indicated that part of the BW depression could be attributed to malabsorption of nutrients. It was concluded that the atypical E. coli colony Types 1 and 2 play a significant role in the PEMS disease.


Poultry Science | 2002

Influence of a propionic acid feed additive on performance of turkey poults with experimentally induced poult enteritis and mortality syndrome

R. D. Roy; F. W. Edens; C. R. Parkhurst; M. A. Qureshi; G. B. Havenstein

Abstract Poult enteritis and mortality syndrome (PEMS) has multiple etiological agents associated with its occurrence, including two viruses and at least three Escherichia coli isolates. Myco Curb (MC) contains organic acids and is used as a feed additive to inhibit growth of many bacteria and toxin-producing molds but not viruses. Studies evaluating the influence of MC on BW, feed conversion, and mortality indicate that turkey poults tolerate MC at 1.25% but not 2.50%, but higher MC content in feed provides greater suppression of growth of bacterial isolates commonly associated with PEMS. In two PEMS experiments, 1.25% MC was blended into poult starter feed and was maintained in the feed for the duration of the 3-wk experiments. In these experiments, 1-d-old commercial poults were placed into battery brooders and were given turkey starter feed and water ad libitum. At 6 d posthatch, PEMS-designated poults were given a 1-mL oral gavage of a 10% suspension of feces from PEMS-infected poults. BW depression due to PEMS was not alleviated by MC, although there was less variation in mean BW of the MC-fed poults, and there was a highly significant reduction in mortality (68% in PEMS-exposed with MC vs. 32.5% in PEMS-exposed without MC). The reduction in mortality in the MC-fed poults was attributed to decreased bacterial content of the gut and to maintenance of packed cell volume and hemoglobin content. It was concluded that MC might be a potential nutritional intervention during PEMS.


Health Physics | 1977

Humoral immunity of Japanese quail subjected to microwave radiation during embryogeny.

Philip E. Hamrick; Donald I. McRee; P. Thaxton; C. R. Parkhurst

Fertile Japanese quail eggs were exposed to continuous wave microwave radiation at an intensity of 5 mW/cm2 (50 W/m2) and a frequency of 2450 MHz. The absorbed power density was determined to be 4.03 W/kg. The eggs were exposed throughout the first 12 days of the normal incubation period of 17.5 days. Non-exposed control eggs were incubated in a chamber identical to the exposure chamber. After hatching, exposed and control quail were reared in the conventional laboratory manner. Weekly body weight measurements were made to compare the growth patterns of exposed and control quail. The weights of the exposed male at the ages of 4 and 5 weeks were 12 and I % , respectively, less than the control males. These differences approached statistical significance ( P ~ 0 . 0 5 ) . At 5 weeks of age the quail were challenged with sheep red blood cells (SRBC) and the levels of the anti-SRBC antibodies were determined. The levels of specific anti-SRBC antibodies, determined 4 days after antigen challenges, were of the same magnitude for both the exposed and control quail. Following this assessment of humoral immunity, the quail were sacrificed and the bursa of Fabricius and spleen were removed and a comparison was made of exposed and control birds. The weights of the bursa of Fabricius and spleen were not altered significantly by the microwave exposure. Research Triangle Park, NC27709 PAUL THAXTON and CARMEN R. PARKHURST


Immunological Investigations | 1977

Antibody Responses to Xenogeneic Red Blood Cell Challenge in the Japanese Quail

E. H. Benton; G. W. Morgan; P. Thaxton; C. R. Parkhurst; M. O. Shambley

Previous reports indicate that Japanese quail are hyporesponsive to such conventionally used antigens as sheep red blood cells and bovine serum albumin. In this study the immune responsiveness of Japanese quail to several erythrocyte antigens was investigated. The quail produced higher antibody titers when immunized with chukar red blood cells than when immunized with sheep, turkey, or pheasant red blood cells. It is concluded that Japanese quail are capable of producing HA titers comparable in magnitude to those demonstrated by other laboratory animals, when the quail are immunized with an appropriate antigen. Chukar red blood cells are such an antigen.


Experimental Biology and Medicine | 1973

Abnormal Mating Behavior and Reproductive Dysfunction Caused by Mercury in Japanese Quail

J. Paul Thaxton; C. R. Parkhurst

Summary The results of this study support previous findings that Hg does reduce the reproductive potential of the female of avian species (3, 4). Additionally, the dangers of Hg are not relegated entirely to the female, but rather it is concluded that Hg exerts an equally adverse effect on the reproductive potential of the avian male. The loss of reproductive efficiency which is caused by Hg in both male and female quail may be correlated directly to a diminution in their normal mating behavior.


Comparative Biochemistry and Physiology Part C: Comparative Pharmacology | 1988

Hematological effects of ethyl methanesulfonate, paraquat and phenylhydrazine in Japanese quail

M.W. Clark; R.P. Gildersleeve; J. P. Thaxton; C. R. Parkhurst; Donald I. McRee

1. Juvenile Coturnix coturnix japonica males were injected intravenously with 2, 20 or 200 mg ethyl methanesulfonate (EMS)/kg body wt; 0.2, 2 or 20 mg paraquat (PARA)/kg body wt; or 0.6, 6 or 60 mg phenylhydrazine (PHZ)/kg body wt; and hematologic variables were measured at 0 (non-injected), 24 and 72 hr post-injection. 2. EMS, PARA and PHZ-induced hemolytic anemia began within 24 hr post-injection. 3. Recovery from anemia began within 72 hr post-injection of EMS or PARA, but PHZ injected quail continued to show a marked anemia at that time. 4. EMS and PARA induced lymphocytopenia, monocytopenia and heterophilia, while PHZ induced lymphocytosis, monocytopenia and heteropenia after injection. 5. These results suggest that the anemia induced by EMS and PARA was dissimilar from that induced by PHZ, that all chemicals affected leukopoiesis and that Japanese quail can mount a marked recovery from the hematologic affects of PARA, a widely used herbicide, in a short interval after intoxication.


Poultry Science | 1998

Hypothermia, hypoglycemia, and hypothyrosis associated with poult enteritis and mortality syndrome

R. E. Doerfler; F. W. Edens; C. R. Parkhurst; G. B. Havenstein; M. A. Qureshi

Abstract A metabolic dysfunction contributes to the poor performance and mortality associated with Poult Enteritis and Mortality Syndrome (PEMS). Within 2 d after contact-exposed poults were removed from the presence of PEMS-infected poults and returned to their respective treatment rooms to infect experimental poults, the experimental poults began to huddle together and show signs of the disease. When separated from the huddle, body temperatures of exposure poults were depressed significantly. Body temperatures decreased progressively through 8 d after exposure with a maximum depression of 2 C and returned to a normal level at 18 d after PEMS exposure. Similar decreasing patterns in serum glucose, inorganic phosphorus, triiodothyronine, and thyroxine were observed, with maximum decreases in these serum constituents being found between 8 and 13 d after PEMS exposure. There were significant correlations among decreasing body temperatures, decreasing serum constituents, and mortality in the PEMS-exposed poults. Daily mortality rates associated with PEMS began at 6 d and peaked at 9 d after PEMS exposure. Mortality rates decreased from 9 to 15 d after experimental PEMS exposure. Depressions in serum constituents, body temperature, and increased mortality rates did not coincide with decreased feed intake associated with PEMS. Therefore, it was concluded that the agent(s) causing PEMS may have a direct effect on energy metabolism in afflicted poults.


Comparative Biochemistry and Physiology Part A: Physiology | 1987

Hematology of Japanese quail selected for high or low serum corticosterone responses to complex stressors

R.P Gildersleeve; D.G Satterlee; T.R Scott; Donald I. McRee; C. R. Parkhurst; M.E Cook

Blood was collected from random-bred male Coturnix coturnix japonica and from quail selected genetically for high or low serum corticosterone responses to complex stressors after chronic exposure to short daily photoperiods and after exposure to long photoperiods. When compared to the low response quail, high response quail exhibited increased mean cellular hemoglobin values, reticulocyte numbers and heterophil percentages, and decreased monocyte and eosinophil numbers after exposure to long photoperiods. The data indicate that these corticosterone response lines can be partitioned by their hematological responses to photoperiodic manipulation.

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F. W. Edens

North Carolina State University

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P. Thaxton

North Carolina State University

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George J. Mountney

United States Department of Agriculture

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Donald I. McRee

National Institutes of Health

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G. R. Baughman

North Carolina State University

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G. B. Havenstein

North Carolina State University

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M. A. Qureshi

North Carolina State University

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G. W. Morgan

North Carolina State University

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M. B. Timmons

North Carolina State University

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Pat B. Hamilton

North Carolina State University

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