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M A Goodwin

Publications and source records attributed to M A Goodwin.

At least 55 records · Page 3Linked to original sources

Relationship of the enzyme-linked immunosorbent assay to indirect immunofluorescent antibody test for the detection of so-called chicken anemia agent antibodies in serum from broiler breeders.

Serum samples collected from breeder chickens ranging in age from 1 day to 55 weeks were tested for CAA antibodies by enzyme-linked immunosorbent assay (ELISA) and indirect immunofluorescent antibody (IFA) test. The relationship of ELISA to IFA test was determined. The sensitivity of the ELISA relative to the IFA test was 82.64%, and the specificity of the ELISA relative to the IFA test was 56.25%. Agreement between the ELISA and the IFA test was highly significant (Kappa = 0.74, Z = 5.78). We concluded that the ELISA is as good as the IFA test for detecting CAA antibody in sera from chickens.

Anemia↗

Incidence of anemia and polycythemia in clinically ill Georgia broilers.

The incidence of anemia and polycythemia was established in clinically ill Georgia broilers that were tested for packed cell volume (PCV) during 1988 and 1989. More than 66% (324/488 = 66.4%) of PCV-tested broiler chicks were anemic, and less than 2% (8/488 = 1.6%) of PCV-tested chicks were polycythemic. The incidence of anemia was significantly (P less than 0.001) higher than expected (2.5%) at age 7 days (56.9%), 14 days (83.9%), 21 days (74.7%), 28 days (58.7%), and 35 days (57.9%). The incidence of polycythemia was significantly (P less than 0.001) higher than expected (2.5%) in 35-day-old broilers (21.1%) but was not significantly different from the expected rate in broilers at age 7 days (0%), 14 days (1.8%), 21 days (0.3%), and 28 days (4.3%). The established rates for anemia were much higher than we would have hypothesized. This led us to believe that either 1) an etiology for anemia is present in epizootic proportions in Georgia broilers, or 2) the standard method for establishing reference intervals for anemia in animals does not apply to broiler chicks.

Anemia↗

Development and comparison of serologic methods for diagnosing chicken anemia virus infection.

This paper describes the development of an indirect immunoperoxidase assay (IIP) and an indirect enzyme-linked immunosorbent assay (ELISA) for detecting antibodies to chicken anemia virus (VAC). The IIP assay developed used CAV-infected MDCC-MSB1 cells for detecting antibody to CAV, whereas the ELISA utilized gradient-purified immunoadsorbed CAV as the target antigen. The IIP and ELISA were compared with the standard indirect immunofluorescent antibody (IFA) assay, which is more conventionally used to screen chicken serum for antibodies against CAV. Comparative test results of 185 field samples of chicken serum by these three methods were in agreement 84% of the time. Both IFA and IIP assays yielded fewer positive tests than did the ELISA. IFA and IIP assays were in agreement 93% of the time, as compared with 91% agreement of IIP and ELISA results, or 84% agreement for comparative IFA and ELISA results.

Anemia↗

Increasing incidence of anemia among clinically ill Georgia broilers: 1988-89 vs. 1990.

The incidence of anemia in clinically ill Georgia broilers climbed from 66.4% (324/488) during 1988-89 to 80.9% (531/656) during 1990. The incidence of polycythemia fell from 1.6% (8/488) during 1988-89 to 1.5% (10/656) during 1990. Specifically, compared with 1988-89, the 1990 incidence of anemia increased significantly in chicks at age 7 days (P = 0.0002) and 28 days (P = 0.05). We have no certain explanation for this shifting incidence of anemia in clinically ill Georgia broilers. Anemic chicks have plasma that contains virus particles with morphologic characteristics consistent with a virus (chicken anemia agent [CAA]) known to cause anemia in chickens. If CAA is the predominant etiology for anemia in clinically ill Georgia broilers, then our observation could be easily explained. The increasing rate of anemia could indicate a decline in broiler health over time.

Anemia↗

Comparisons of packed cell volumes (PCVs) from so-called chicken anemia agent (CAA; a virus)-free broilers to PCVs from CAA-free specific-pathogen-free leghorns.

Packed cell volumes (PCVs) from 3-, 7-, 14-, 21-, 28-, and 35-day-old clinically healthy chicken anemia agent (CAA)-free and specific-pathogen-free (SPF) leghorn chicks were compared with PCVs from age-matched clinically healthy CAA-free broiler chicks. The PCVs of the SPF chicks regressed significantly (F = 20.6, df = 2/3, P < 0.025) on age in a linear fashion. The PCVs of the broiler chicks regressed significantly (F = 9.56, df = 2/3, P < 0.05) on age in a cubic parabola. The mean PCVs of the broiler chicks were significantly (P < 0.05) higher than PCVs of SPF chicks at every tested time interval. Results indicate that PCV values are higher in broiler chicks than in SPF leghorn chicks, and that PCVs increase as chicks age. Clinicians, diagnosticians, and investigators who intend to work with chicken blood must be aware of these differences.

Anemia↗

Inability of so-called chicken anemia agent (CAA) infections to be diagnosed by anemia and hematopoietic organ atrophy alone.

In the recent past, anatomic and clinical pathologic diagnoses of so-called chicken anemia agent (CAA) infections have been based on lesions such as anemia and hematopietic organ atrophy (HOA). In the present study, significant (P less than or equal to 0.05) positive and negative correlations were seen in a lesion matrix constructed from 89 cases of anemia and HOA in Georgia broilers during 1988 and 1989. Only splenic atrophy and bursal atrophy were not significantly associated. We concluded that information regarding only HOA and anemia is not sufficient to allow pathologists to diagnose CAA in broiler chickens submitted to diagnostic laboratories such as ours.

Anemia↗

Packed cell volume reference intervals to aid in the diagnosis of anemia and polycythemia in young broiler chickens.

Packed cell volume (PCV) reference intervals were established for use in diagnosing anemia and polycythemia in young broiler chickens. Blood samples were collected from one hundred twenty 3-to-49-day-old clinically healthy conventionally reared broiler chickens. PCVs were determined and analyzed. PCVs regressed significantly (P less than 0.025) on age, which shows that neonatal physiologic anemia occurs in broiler chickens, as well as in mammals and specific-pathogen-free (SPF) chickens. The definition for anemia in broiler chicks varies with age. We defined anemia as a PCV less than or equal to 26%, 29%, 33%, 32%, 33%, 33%, 31%, and 28% for broiler chickens, 3, 7, 14, 21, 28, 35, 42, and 49 days old, respectively. We define polycythemia as a PCV greater than or equal to 42%, 43%, 41%, 40%, 42%, 42%, 41%, and 40% for broiler chickens 3, 7, 14, 21, 28, 35, 42, and 49 days old, respectively. Otherwise, broiler chickens have PCVs within established reference intervals. Results provide guidelines for detecting anemia and polycythemia in young broiler chickens of various ages.

Analysis of Variance↗

Toxicological pathology of cockleburs (Xanthium spp.) for broiler chickens.

Spiking mortality syndrome (SMS) in chickens resembles cocklebur toxicity in cattle, sheep, pigs, and rats. In order to determine if cockleburs are toxic to broiler chicks, crushed burs were fed (25% wt:wt) to broilers for 21 days. Ingestion of cockleburs resulted in significant failure to properly gain body weight. Otherwise, chicks did not develop clinical signs of illness or gross or microscopic lesions. Although there were some significant differences in serum chemistry values among chick groups, there were no consistent patterns. Severe hypoglycemia is said to be a characteristic finding in chicks that die with SMS. Because glucose levels were not low in chicks that were fed cockleburs, we feel certain that cockleburs do not cause SMS.

Animal Feed↗

Comparison of histopathology to the direct immunofluorescent antibody test for the diagnosis of infectious laryngotracheitis in chickens.

Histopathology and direct immunofluorescent antibody (DIFA) tests were compared for diagnoses of infectious laryngotracheitis (ILT) in 144 cases of spontaneous respiratory disease in chickens presented to the Georgia Poultry Laboratory during 1988. For the 48 cases in which ILT was diagnosed, correct histologic diagnoses were made 100% (48/48) of the time and correct DIFA diagnoses were made 96% (46/48) of the time. For the 96 cases in which ILT was not diagnosed, correct histologic and DIFA diagnoses were made in every case. A Kappa test showed that DIFA was as effective as histopathology for the diagnosis of ILT in chickens (P = 0.0). It was concluded that increased use of DIFA could be instrumental in the abatement of ILT in chickens.

Animals↗

Diagnoses of infections by the so-called chick anemia agent: anemia and direct transmission electron microscopic detection of virus.

Blood from 48 chicks was examined for anemia (packed cell volume), and plasma was examined for virus particles by direct transmission electron microscopy (DTEM). There was agreement between the occurrence of anemia and the presence of CAA virus particles in plasma from anemic chicks (Kappa = 0.2425, Z = 2.096, P = 0.036). Although DTEM is a method that can be used to diagnose CAA in chicks, more sensitive, economical and less laborious diagnostic assays are needed.

Anemia↗

Clinical, pathological, and epizootiological features of long-segmented filamentous organisms (bacteria, LSFOs) in the small intestines of chickens, turkeys, and quails.

Long-segmented filamentous organisms (LSFOs) are easily recognized gram-positive bacteria that infect several species of animals. The present study describes the epizootiological, clinical, and pathological characteristics of LSFOs in chicks, turkey poults, and quails in Georgia and California. LSFOs are most likely to be seen in young poultry that have gastrointestinal illnesses during winter. Concomitant infections with other bacteria and protozoans are common. Although inflammation and displacement of microvilli are characteristics of LSFO infections in these birds, LSFOs are not necessarily pathogens. They may be normal intestinal flora or commensal organisms that overgrow when certain unknown gastrointestinal conditions are correct or certain unknown events occur.

Animals↗

Pathogenicity of CL-1 chicken anemia agent.

Twelve-day-old broiler-type chickens had hemorrhagic necrotic wing tips. After 10 blind subcultures in an MDCC-MSB1 cell line, a virus (so-called chick anemia agent [CAA]) was isolated and designated CL-1 CAA. Five-day-old specific-pathogen-free chicken embryos from a commercial breeder flock that were found not to possess antibody against CAA were infected with CL-1 virus via yolk-sac injection. Many (49%) infected embryos were small and apparently had died from severe systemic hemorrhage. Hatched chicks were small and had pale feathers, skin, skeletal muscles, bone marrow, and viscera. All infected chicks had small thymuses. These thymuses often were so small that they could not be found grossly (P = 0.002). Anemia occurred within 4 days post-hatch. Microscopically, all hematopoietic organs were markedly atrophic. Septic necrotizing lesions were seen only in organs from CL-1-injected chicks. Physicochemical and pathological characteristics of this virus indicate that it is similar to other isolates of CAA found in Europe and Japan.

Anemia↗

Packed cell volume reference intervals to aid in the diagnosis of anemia and polycythemia in young leghorn chickens.

Packed cell volume (PCV) reference intervals were established for use in diagnosing anemia and polycythemia in young chickens. Blood samples were collected from 3-to-35-day-old specific-pathogen-free leghorn chicks. PCVs were determined and analyzed. PCVs regressed significantly (P less than 0.0001) on age, which shows that neonatal physiologic anemia occurs in chicks as well as in mammals. The definition for anemia in chicks varies with age. We defined anemia as a PCV less than or equal to 23%, 25%, 26%, 28%, 31%, and 30%, respectively, for chicks 3, 7, 14, 21, 28 and 35 days old. We defined polycythemia as a PCV greater than or equal to 36%, 37%, 38%, 37%, 41%, and 40%, respectively, for chicks 3, 7, 14, 21, 28, and 35 days old. Healthy chicks have PCVs within established reference intervals. Results provide guidelines to detect anemia and polycythemia in young leghorn chicks of various ages.

Anemia↗

A survey for parvovirus-like virus (so-called chick anemia agent) antibodies in broiler breeders.

A prospective study to survey for the presence of parvovirus-like virus (PVLV; so-called chick anemia agent) antibody in broiler breeder pullets in Georgia, North Carolina, and Florida was conducted by collecting serum samples from 52 breeder flocks that ranged in age from 1 day to 55 weeks old. Results indicated that PVLV infection was widespread. Ninety-eight percent (51/52) of chicken flocks and 62% (530/861) of chickens had PVLV antibody. Rates of antibody-positive chickens among flocks ranged from 0% to 100% and averaged 76%. Upon initial examination, the percentages of chickens positive for PVLV appeared evenly distributed with respect to several convenient age groups and geographic locations. However, compared with young chickens (less than or equal to 19 weeks old), markedly significantly lower proportions of positives were present among chickens more than 19 weeks old (P = 0.00001) or chickens 30 weeks old or more (P = 0.000004). Also, there were significant (F = 7.7, df = 3/827, P less than 0.001) differences among the rates of PVLV antibody in chickens among various companies. The relatively high rate of PVLV antibody among broiler breeder chickens helps explain the low incidence of clinical disease among their offspring.

Age Factors↗

The relationship of Cryptosporidium sp. infection of the bursa of Fabricius, intestinal tract, and respiratory system of chickens in Georgia, 1974-1988.

During 1974-1984, cryptosporidiosis was diagnosed in slightly more than 1% (63/6050 = 1.04%) of histopathology reports on chickens and turkeys made at two Georgia diagnostic laboratories. During 1985-1988, cryptosporidiosis was diagnosed in almost 6% (157/2622 = 5.99%) of histopathology reports on chickens and turkeys made at the two laboratories. Intestinal and respiratory Cryptosporidium sp. infections have increased significantly (p less than 0.01) with time. During the same period, there was no statistical pattern for bursa of Fabricius Cryptosporidium sp. infections, and there was no relationship between the incidence of bursal infections and the incidence of either respiratory or intestinal infections.

Animals↗

Effect of Cryptosporidium baileyi on broilers infected at 26 days of age.

Cryptosporidium baileyi causes respiratory disease, pallor, death, and transient increased feed conversion (FC) and decreased body weight gain (BWG) when intratracheally (IT) inoculated into young chicks. Unlike the case for young chicks in previous studies, C. baileyi had no effect on FC, BWG, or mortality in IT-inoculated 26-day-old chicks. Results from two different histologic evaluations indicated that IT inoculation with 10(4) oocysts caused higher epithelium lesion scores (P less than 0.05) and higher mucosal area scores (P less than 0.05) than did IT inoculation with more, fewer, or no oocysts. Reasons for these findings and implications of chicken immune system response to or modulation by C. baileyi are discussed.

Animals↗

Rapid cytologic diagnosis of respiratory cryptosporidiosis in chickens.

A method is presented for the rapid cytologic detection of cryptosporidial oocysts in Diff-Quik and modified Kinyoun acid-fast-stained tracheal imprints. On Diff-Quik-stained preparations, cryptosporidial oocysts were observed attached to the apical ends of respiratory epithelial cells or scattered throughout the imprint. These oocysts were round to oval, measured approximately 6 to 7 micron in diameter, and appeared faintly blue with fine pink granules. In modified Kinyoun acid-fast-stained tracheal imprints, the oocysts usually were pink to bright red against a blue background. Cytologic examination of tracheal imprints following Diff-Quik and modified Kinyoun acid-fast staining provides a rapid, reliable, and economical method for diagnosis of respiratory cryptosporidiosis in poultry.

Animals↗

Infectious anemia caused by a parvovirus-like virus in Georgia broilers.

Pale chicks with necrotic dermatitis, small bursas of Fabricius (BFs), small thymuses, pale bone marrow, and watery blood were suspected of having parvovirus-like virus- (PVLV) associated disease. Histologic lesions included atrophy or hypoplasia of thymuses and BFs, and septic necrotizing clostridial dermatitis and hepatitis. Clostridium perfringens was cultured from skin and liver. A PVLV was isolated in a Marek's disease tumor cell line (MDCC-MSB1) culture and was identified by physicochemical, immunofluorescent, and morphologic features. This isolate was named GA-1 PVLV. Specific-antibody-negative chicks and embryos infected with heat- or chloroform-treated GA-1 PVLV developed anemia at the same rate. Control chicks never were anemic. This is the first isolation of PVLV from clinically ill chickens in the United States and the first report of PVLV-induced anemia in chickens in the Western Hemisphere.

Anemia↗