Changes in circulating prostaglandin E and F2 alpha levels, cloacal temperature, and leukocyte counts in turkeys inoculated with Pasteurella multocida.

The inoculation of Pasteurella multocida (P-1059) intravenously into turkeys increased significantly the plasma prostaglandin (PG) F2 alpha levels to 157% of the control values and the plasma PGE levels to 171% of control values at 3 hr after treatment. At 12 hr, the cloacal temperature of the inoculated birds was significantly higher than that of the control. The leukocyte count of inoculated birds remained unchanged from that of the control. However, the differential leukocyte count shifted in favor of significant increases in heterophils and decreases in lymphocytes and monocytes at 6 and 12 hr after inoculation. This study provides evidence that increases in plasma levels of PGF2 alpha and PGE may be partly responsible for the clinicopathological manifestations of acute fowl cholera.

An experimental soft-release of oil-spill rehabilitated American coots (Fulica americana): II. Effects on health and blood parameters.

The Unocal-Metrolink oil spill of 21 February 1995 resulted in approximately 7800 barrels of San Joaquin crude oil being deposited into the San Gabriel River in Huntington Beach, CA, USA. In order to determine long-term pathological effects of oil exposure and rehabilitation, hematological and serum biochemical parameters for both rehabilitated (RHB) American coots (Fulica americana) and reference (REF) coots were examined every 3-4 weeks (56, 81, 108 and 140 days post oil exposure) after birds were cleaned, rehabilitated and soft-released. Most significant differences in monthly comparisons between RHB and REF birds occurred 56 days following oil exposure. Total white blood cell (WBC) count, albumin:globulin (A:G) ratio and calcium concentration were higher in RHB birds compared to REF birds 56 days post oil exposure. In addition, mean cell hemoglobin (MCH), mean cell hemoglobin concentration (MCHC), alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase and creatine kinase activities, and creatinine, total protein (TP) and globulin concentrations were lower in RHB birds. Blood results from 56 days post oil exposure for RHB coots which subsequently died were compared to blood results from days 108 and 140 for REF coots which survived. Oiled and rehabilitated birds which died had significantly higher WBCs, packed cell volume, TP and globulin concentrations, and lower A:G ratio, MCH, MCHC, glucose and sodium concentrations compared to REF birds which survived. Blood result differences detected at 3-4-week intervals between RHB and REF survivors, and differences detected between RHB coots which died and REF coots which survived, suggested that RHB coots developed an inflammatory response (infectious or non-septic) and, concurrently, may have experienced decreased immune responsiveness. Additionally, RHB coots experienced either an iron (Fe) utilization or Fe metabolism problem. These pathophysiological mechanisms were consistent with increased hemosiderin (stored Fe) present in the liver, spleen and kidney of necropsied RHB birds, and may have contributed to RHB coot mortality. When blood parameter differences were examined for their impact on survival time, it was determined that RHB coots had shorter survival times if they had very high cholesterol (> or =449 mg/dl) or chloride (> or =110 MEQ/l) concentrations on day 56 post oil exposure. Interestingly, the lack of differences between RHB and REF coots from day 81 through day 140 suggested that, from a hematologic and clinical chemistry perspective, coots which were oiled, rehabilitated, released and survived at least 3.5 months could not be differentiated from wild (REF) coots. From these findings it appears that blood analysis, coupled with post-release survival data, may help discern reasons for increased mortality of oiled and rehabilitated birds, compared to non-oiled reference birds.

Evaluation of the haemostatic profile in the pre- and post parturient mare, with particular focus on the perinatal period.

Various haemostatic analytes were systematically evaluated for four months pre-partum and five months post partum in 14 healthy mares. The plasma fibrinogen concentration and both Factor VIII:C and von Willebrand factor activity showed gradual increases from mid-gestation and reached maximal, or near maximal activity at parturition. These increases were paralleled by an increase in plasma fibronectin concentration, the appearance of fibrinogen degradation products, and a modest rise in antithrombin III concentration. In contrast, the activity of Factor VII and Factor IX, and the one-stage prothrombin (PT) time and the activated partial thromboplastin (APTT) time remained relatively constant throughout the pre- and post parturient period.

Haematological, bone marrow and clinical chemical changes in neonatal foals given canine recombinant granulocyte-colony stimulating factor.

Five Thoroughbred and Quarter Horse cross foals were given 20 micrograms canine recombinant granulocyte-colony stimulating factor (rcG-CSF) per kg bwt intramuscularly (i.m.) on the day of birth and 10 micrograms rcG-CSF/kg for 13 additional days. During this time and for an additional 21 days haematology, bone marrow and clinical chemical analyses were performed. After one day of rcG-CSF administration leucocyte and neutrophil counts increased from 9.16 x 10(9)/l to 23.44 x 10(9)/l and from 6.45 x 10(9)/l to 19.61 x 10(9)/l, respectively. The counts continued to increase for the next 3-4 days and then there was a slight decrease. A second increase followed and the leucocyte and neutrophil counts increased to 52.84 x 10(9)/l and 45.16 x 10(9)/l on the day after the last rcG-CSF administration (Day 15). The counts decreased rapidly immediately after the administration of rcG-CSF was stopped and then at a slower rate. The cell counts were still higher than in the controls at the end of the study period (Day 35). Bone marrow cellularity increased from 10-25% before rcG-CSF was given to 60-80% after 5 days. The increase in cellularity was due to increased myeloid activity because the myeloid to erythroid ratio increased from 2.7 to 8.8. Serum chemistry changes were minimal although foals given rcG-CSF at various times had lower glucose concentrations and increased alkaline phosphatase and gamma glutamyl transferase activities.

Probable essential thrombocythemia in a dog.

Essential thrombocythemia (ET) in an 11-year-old dog was characterized by persistently high platelet counts (range, 4.19 X 10(6)/microliters to 4.95 X 10(6)/microliters, abnormal platelet morphology, marked megakaryocytic hyperplasia in the bone marrow, absence of circulating megakaryoblasts, and history of splenomegaly and gastrointestinal bleeding. Increased numbers of megakaryocytes and megakaryoblasts (15% to 20%) in the bone marrow were confirmed by a positive acetylcholinesterase reaction. Another significant finding was the presence of a basophilia in blood (4,836/microliters) and bone marrow. The marked persistent thrombocytosis, absence of reactive (secondary) thrombocytosis, abnormal platelet morphology, and quantitative and qualitative changes in the megakaryocytic series in the bone marrow suggested the presence of a myeloproliferative disease. Cytochemical and ultrastructural findings aided in the diagnosis of ET. The dog was treated with radiophosphorus. The results was a rapid decline in the numbers of megakaryoblasts and megakaryocytes in the bone marrow and platelets and basophils in the peripheral blood. The dog died unexpectedly of acute necrotizing pancreatitis and diabetes mellitus before a complete remission was achieved.

Chemotaxis of horse polymorphonuclear leukocytes to N-formyl-L-methionyl-L-leucyl-L-phenylalanine.

Horse polymorphonuclear leukocytes (PMN) isolated from horse blood by sedimentation and isotonic lysis and having about 25% accompanying lymphocytes were as effective at chemotaxis as nearly pure PMN isolated by density gradient techniques. N-Formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP), used as a representative of the formylmethionyl peptides (produced by prokaryocytic organisms), was effective as a chemoattractant only at the high concentration of 10(-4) M. When serum was preincubated with FMLP at concentrations as low as 10(-8) M, the serum attracted horse PMN. This activity was not generated when heat-inactivated (56 to 60 C for 30 minutes) serum was used. A combination of FMLP and zymosan was no more effective than zymosan alone in generating serum chemoattractants. The results of this study indicate that the FMLP is a weak chemoattractant for horse PMN, but that FMLP has the capability similar to that of zymosan to activate complement to produce PMN chemoattractants.

Reference ranges for hematologic and serum biochemical values in llamas (Lama glama).

Hematologic and serum biochemical values were determined in 174 llamas of all age groups and both sexes from ranches in California and Nevada. Compared with hematologic values for horses and cattle, llama erythrocytes were more numerous (10.1 to 17.3 x 10(6)/microliters), but the PCV was lower (25 to 45%) because the smaller elliptical cells pack tighter. The mean corpuscular volume was half that of horses and cattle (22 to 29.5 fl). The mean corpuscular hemoglobin concentration was higher (38.9 to 46.2 g/dl), and the mean corpuscular hemoglobin slightly lower (9.6 to 12.6 pg). Most serum biochemical values were similar to those of cattle and horses, with the exception of triiodothyronine (48 to 468 ng/dl) and thyroxin (9.8 to 30 micrograms/dl), which are up to 10 times higher than values for other domestic species.

Heterogeneity in phagocytic and nitroblue tetrazolium reductive properties of neutrophils from cows.

Phagocytic and nitroblue tetrazolium (NBT) reductive activities of blood neutrophils from 19 Holstein heifers were measured by light microscopic and spectrophotometric methods, respectively. These functional properties of neutrophils correlated well (r = 0.64) and varied significantly (P less than 0.05) among animals studied. Variations in phagocytosis and NBT reductive activities attributable to the source of sera were determined in experiments in which cells from the same cows and zymogen particles opsonized with heat-inactivated autologous or homologous sera were used. Variations attributable to the source of cells were determined in experiments in which cells from different cows and particles opsonized with pooled sera from all the cows were used. Most of the variation in phagocytic properties and NBT reductive activities was attributable to the source of cells (ie, each cow). The source of sera contributed slightly to the variation in NBT reductive activities, but not to the phagocytic properties. These results support the concept of functional heterogeneity of neutrophils among cows.

Prevalence of mycoplasmas and immune responses to Mycoplasma bovis in feedlot calves.

Microbiological cultural, cytologic, and immunologic observations were made on 30 calves. The eyes, nares, and bronchioalveolar region were subjected to microbiological cultural examination for mycoplasmas. Four of the examinations of 30 eyes, 15 of those of 30 nasal tissues, and 25 of those of the 30 bronchioalveolar regions from the 30 calves were positive for mycoplasmas. Mycoplasma bovis and M bovirhinis were the most prevalent species. Cytologic examinations of peripheral blood and bronchioalveolar washes did not show pathologic changes. Results of indirect hemagglutination, enzyme-linked immunosorbent assay, lymphocyte-stimulation tests on peripheral blood cells, and skin testing demonstrated only a low prevalence of immune recognition of M bovis. Infection and immune response were studied in 3 calves for 10 weeks before, and for 4 weeks after, intratracheal administration of live M bovis.

Using red blood cell creatine concentration to evaluate the equine erythropoietic response.

Red blood cell creatine concentration was examined to determine its association with the equine erythropoietic response. Studies were conducted on 9 healthy horses, 4 healthy ponies, 24 anemia horses, and 2 horses in which anemia was experimentally induced. A modified Jaffe reaction was used to measure RBC creatine concentration. The mean RBC creatine concentration of the 9 healthy horses was 5.72 +/- 0.42 mg/dl, and that of the 4 healthy ponies was 2.59 +/- 0.31 mg/dl. Density-separation of erythrocytes from the healthy horses revealed significantly higher (P less than 0.001) creatine content (7.72 +/- 0.57 mg/dl) in the young RBC populations than in the old RBC populations (4.03 +/- 0.27 mg/dl). The RBC creatine content was assayed in 19 hot-blooded horses which were anemic due to a variety of causes. Of these anemic horses, 12 with PCV between 25% and 30% had a mean RBC creatine concentration of 6.12 +/- 0.46 mg/dl. The 7 other anemic horses with PCV less than 25% had a mean RBC creatine value of 6.07 +/- 0.12 mg/dl. Bone marrow films were examined from 5 anemic horses and in the 2 horses in which anemia was experimentally induced. The RBC creatine concentration correlated positively (P less than 0.001) with the reticulocyte count in the bone marrow and negatively with the myeloid-erythroid ratio (P less than 0.001).

Reference ranges and the influence of age and sex on hematologic and serum biochemical values in donkeys (Equus asinus).

Hematologic and serum biochemical values were determined in blood samples from 217 donkeys (Equus asinus). Donkeys were classified on the basis of size, sex, age, and whether they were domestic or feral. Parametric (mean +/- 2 SD) and nonparametric (2.5th to 97.5th percentile) reference ranges were calculated for each analyte. For all donkeys, 26 of 46 analytes significantly departed from gaussian distribution. Serum lactate dehydrogenase activity in miniature donkeys was higher than that in other donkeys. Differential leukocyte counts in feral donkeys differed from those in other types in ways that suggested that the former had smaller parasite loads or experienced greater stress. Erythrocyte, lymphocyte, and platelet counts and fibrinogen, glucose, inorganic phosphorus, and potassium concentrations decreased with age. Eosinophil counts, mean corpuscular volume, and plasma protein, serum protein, and serum globulin concentrations increased with age. Female donkeys had significantly (P less than 0.05) higher mean corpuscular hemoglobin concentration and leukocyte and neutrophil counts than did male donkeys. Mean corpuscular hemoglobin increased with age, and females had higher values than did males of all age groups. An interaction between age and sex was observed for alkaline phosphatase activity, with a trend for decreased activity with age.

Xylazine causes transient dose-related hyperglycemia and increased urine volumes in mares.

Xylazine given IV at doses of 0.5, 1.0, and 1.5 mg/kg to mares caused a significant (P less than 0.05) dose-related increase in serum glucose concentration and urine volume. Serum glucose concentrations as much as 150 mg/dl were recorded in mares after they were given the largest xylazine dose. The greatest urine volume, similar to changes in peak glucose concentration, always occurred during the first hour after dosing with xylazine and averaged 1.82, 3.93, and 5.68 ml/kg/hour after the 0.5-, 1.0-, and 1.5-mg/kg doses, respectively, were given. Urine osmolality and specific gravity were significantly (P less than 0.05) inversely related to urine volume. Although serum glucose concentrations were significantly increased above those measured after IV injection of saline solution, significant glucosuria was not detected.

Modifications of a cholinesterase method for determination of erythrocyte cholinesterase activity in wild mammals.

A method to determine erythrocyte cholinesterase (ChE) activity was modified for use in wild mammals. Erythrocyte ChE of California voles (Microtus californicus) was primarily acetylcholinesterase (AChE), which was similar to the brain and unlike plasma which was primarily butyrylcholinesterase (BChE). Triplicate erythrocyte AChE analyses from individual animals of several species of wild rodents revealed a mean coefficient of variation of 8.7% (SD = 4.3%). Erythrocyte ChE activity of several wild mammals of California revealed that mule deer (Odocoileus hemionus) had the highest erythrocyte AChE activity (1,514.5 mU/ml) and dusky-footed woodrats (Neotoma fuscipes) had the lowest activity (524.3 mU/ml). No ChE activity was found in erythrocytes of several species of birds and fish.

Aspergillosis in common crows in Nebraska, 1974.

During fall 1974, approximately 1,000 to 1,500 common crows (Corvus brachyrhynchos) died of aspergillosis in south-central Nebraska. The birds were debilitated, lethargic and dyspneic. On necropsy, typical lesions of aspergillosis were found in the lungs and air sacs. Histopathologic examination revealed granulomatous lesions around fungal hyphae in the respiratory system.

Treatment of captive giant Canada geese affected by avian cholera.

In the spring of 1975, an epornitic of avian cholera in Nebraska affected wild waterfowl, common crows (Corvus brachyrhynchos), and a captive flock of guant Canada geese (Branta canadensis maxima). Measures taken to control the disease in the captive geese included flushing the water of their pen with fresh well water, parenteral (50mg oxytetracycline intramuscularly) and feed (tetracycline 500 g/ton) antibiotic treatment, and removing dead waterfowl and crows from the pen, and keeping wild waterfowl and crows out of the pen. Other measures taken to prevent a recurrence of the outbreak included monitoring the area with susceptible sentinel birds and culturing nasal swabs for Pasteurella multocida. Young Canada geese and wood ducks (Aix sponsa) raised in the area also were cultured before release to assure that carriers would not be released into the wild. Presently, ponds in the pen have been dried up so that the area is less attractive to wild waterfowl. Swine feeders and waterers that have been modified to discourage their use by crows are being used to feed and water the geese.

An epornitic of avian cholera in waterfowl and common crows in Phelps County, Nebraska, in the spring, 1975.

In the spring of 1975, many species of waterfowl and common crows (Corvus brachyrhynchos) were found dead in Phelps County, Nebraska. About 25,000 water fowl and at least 3,000 crows died in the epornitic. Few waterfowl were seen dying, but the crows experienced a chronic illness during which they became debilitated and were lethargic and dyspneic. Gross and microscopic lesions in the waterfowl were typical for acute avian cholera. The crows had dark, firm areas within the lungs, loosely adhered yellow fibrous material in the pericardial sac and air sacs and, occasionally, liver abscesses. Microscopically, focal purulent pneumonia was present and a fibrinopurulent exudate overlaid a granulomatous reaction on the heart and lung surfaces. Isolation of Pasteurella multocida serotype 1 confirmed the diagnosis of acute and chronic avian cholera in the waterfowl and crows, respectively.

Chronic lymphocytic leukemia in the dog.

Lethargy and weight loss were associated with chronic lymphocytosis in a dog. The bone marrow was infiltrated with large numbers of small lymphocytes, similar to those appearing in blood. Clinical and laboratory examinations led to a diagnosis of chronic lymphocytic leukemia. Four other cases of chronic lymphocytic leukemia were evaluated retrospectively.

Diagnostic value of pericardial fluid analysis in the dog.

The physical, chemical, and cytologic characteristics of 50 pericardial effusions were reviewed to determine their value to the clinician for distinguishing a variety of pericardial disorders in the dog. Pericardial fluid analysis allowed identification of chylous and bacterial pericardial effusions. Overlap in the ranges of RBC counts, nucleated cell counts, and protein concentrations between dogs with neoplastic and nonneoplastic disorders precluded identification of the cause of the effusion. Of 19 neoplastic effusions, 74% were not detected on the basis of cytologic findings and 13% of 31 nonneoplastic effusates were falsely reported as positive or suspect for a neoplasm. It was concluded that pericardial fluid analysis, including cytologic examination, did not reliably distinguish neoplastic from nonneoplastic disorders.

Myelomonocytic myeloproliferative diseases in a horse.

Myelomonocytic myeloproliferative disease in a horse was diagnosed on the basis of hematologic, enzymatic, and histopathologic findings. It was characterized clinically by depression, weight loss splenomegaly, lymphadenopathy, coagulopathy, and bacteremia. Hematologic findings included severe refractory anemia, thrombocytopenia, monocytosis, and pleomorphic leukocytes, with a left shift of the myeloid series. The serum lysozyme concentration was 14.5 microgram/ml (normal, less than 5 microgram/ml). The bone marrow contained many immature cells of the myeloid series and had a myeloid-to-erythroid ratio of 30.5 to 1. The horse died after brief hospitalization. Necropsy revealed generalized lymphadenopathy and hemorrhages throughout the body. Histopathologically, primitive cells were seen in several tissues. Cells that proliferated in the bone marrow were primarily myeloblastic, with some additional erythropoietic cells. Myeloblastic cells with evidence of normal erythropoiesis were seen in numerous lymph nodes and in the spleen, whereas primarily normal erythropoietic cells proliferated in the adrenal glands. Myeloid blast-type cells predominated in the lungs, myocardium, liver, and kidneys.

Acute myelomonocytic leukemia in a horse.

A 7-year-old Quarter Horse stallion with a myeloproliferative disorder was examined because of colic, and an enterolith was removed surgically. The horse experienced secondary complications after abdominal surgery, and leukopenia and thrombocytopenia were detected. Five months later, the horse was examined for recurrent peripheral edema and for repair of an abdominal incisional hernia. Acute myelomonocytic leukemia was diagnosed, and treatment with low-dose (noncytocidal) cytosine arabinoside was unsuccessful. Necropsy revealed neoplastic infiltrate in the spleen, liver, lung, adrenal gland, testes, and eye. The persistent hematologic abnormalities before the onset of overt leukemia may represent hematopoietic dysplasia or preleukemia.