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Biomedical subjects

E R Jacobson

Publications and source records attributed to E R Jacobson.

At least 73 records · Page 4Linked to original sources
PubMed1993

Seroprevalence of infectious disease agents in free-ranging Florida panthers (Felis concolor coryi).

Serum samples obtained from 38 free-ranging Florida panthers (Felis concolor coryi) in southern Florida, March 1978 through February 1991, were tested for antibodies against eight bacterial, parasitic, and viral disease agents. Sera were positive for antibodies against feline panleukopenia virus (FPV) (78%), feline calicivirus (56%), feline immunodeficiency virus/puma lentivirus (37%), feline enteric coronavirus/feline infectious peritonitis virus (19%), and Toxoplasma gondii (9%). All samples were seronegative for Brucella spp., feline rhinotracheitis virus, and pseudorabies virus. In addition, all the animals tested were negative for feline leukemia virus p27 antigen as determined by enzyme-linked immunosorbent assay. Feline panleukopenia virus was considered to be a potentially significant disease agent; FPV antibodies occurred in the highest prevalences in older age classes (P = 0.027) and in panthers living in the dense mixed hardwood swamps in the western portion of their range compared to the open cypress and sawgrass prairies to the east (P = 0.096). Because < 50 animals remain in this relict population and the probable resultant depression of genetic diversity and lowered disease resistance, FPV or other disease agents could contribute to the extinction of this endangered subspecies.

Animals↗
PubMed1993

Lizard erythrocytic virus in east African chameleons.

Giemsa-stained peripheral blood films from 9 of 50 flap-necked chameleons, Chamaeleo dilepis, and 1 of 18 Fischer's chameleons, Bradypodion fischeri, collected in Tanzania had intraerythrocytic inclusions. In C. dilepis, acidophilic inclusions were associated with the albuminoid vacuoles reported in typical pirhemocytonosis of saurians. Under transmission electron microscopy, the acidophilic inclusions were aggregations of partially or completely formed viral particles consistent with those of the family Iridoviridae. Enveloped viral particles were 140 to 180 nm in diameter, with a mean of 159 nm (SD, 12). Albuminoid vacuoles were not seen in the B. fischeri infection, in which erythrocytes contained multiple acidophilic inclusions of variable shape. Viral particles in B. fischeri were 156.3 to 200.0 nm in diameter; the mean was 180 nm (SD, 18). This represents the first confirmation of the viral identity of pirhemocyton in a lizard. We recommend that the epithet pirhemocyton no longer be used as a generic name under the International Code of Zoological Nomenclature, and that future reports of the etiologic agent refer to it as Lizard Erythrocytic Virus.

Animals↗
PubMed1992

Molecular cloning and partial characterization of a parrot papillomavirus.

The genome of a papillomavirus isolated from a cutaneous lesion on the head of an African grey parrot (Psittacus erithacus timneh) was cloned into pBR322, and a restriction map was prepared. Several short portions of the DNA were sequenced allowing the genome to be aligned with HPV-la. In Southern blot hybridizations, under conditions of low and medium stringency (Tm-40 and -33 degrees), but not at a higher stringency, this viral DNA annealed weakly with only 1 of 17 mammalian papillomavirus genomes tested. Furthermore, PePV DNA hybridized with the DNA from the European chaffinch only at low stringency, indicating that it represents a unique avian papillomavirus.

Animals↗
PubMed1992

Histomorphometric studies of dermal bone in the desert tortoise, Gopherus agassizii.

Dermal bone biopsies were collected from the periphery of the carapaces of adult desert tortoises (Gopherus agassizii) from grazed and ungrazed habitats near the Arizona/Utah border (USA). Quantitative bone histomorphometry was performed on these biopsies as well as on dermal bone biopsies collected from captive juvenile desert tortoises. Except for mild osteomalacia, carapaces of adult desert tortoises from the grazed habitat were relatively normal. No signs of osteopenia were observed. Based on the low numbers of osteoblasts and osteoclasts in dermal bone of both populations of adult desert tortoises, it appears that the peripheral carapace is relatively inert with very low levels of dermal bone turnover. Bone cells and osteoid were more common in dermal bone biopsies from the carapace and plastron of captive juvenile desert tortoises than in adult desert tortoises. However, the great variability in the incidence of bone cells among individuals and the difficulty in collecting juvenile desert tortoises in the field limit the usefulness of dermal bone biopsies from animals of this age group. Based on these results, we propose that dermal bone of the peripheral carapace is a poor sample site for evaluating the effects of dietary or environmental conditions on calcified tissues in desert tortoises.

Animals↗
PubMed1992

Morphologic and cytochemical characteristics of blood cells from the desert tortoise (Gopherus agassizii).

Morphologic and cytochemical staining characteristics of erythrocytes, leukocytes, and thrombocytes of the desert tortoise (Gopherus agassizii) were evaluated, using blood smears prepared from 23 healthy tortoises of Kern County, Calif. Special emphasis was placed on differentiating features of the various leukocytes and thrombocytes. A variety of cytochemical stains, including benzidine peroxidase, Sudan black B, chloroacetate esterase, alpha-naphthyl butyrate esterase, acid phosphatase, leukocyte alkaline phosphatase, periodic acid-Schiff, and toluidine blue were used. Heterophils had a characteristic, large, focal area of positive staining with chloroacetate esterase, alpha-naphthyl butyrate esterase, and acid phosphatase. Eosinophils stained diffusely positive with benzidine peroxidase, allowing differentiation of this leukocyte from heterophils. Thrombocytes stained focally positive with periodic acid-Schiff, allowing differentiation of these cells from lymphocytes, which stained uniformly negative. An intracytoplasmic body, commonly observed within erythrocytes, was considered ultrastructurally to represent a degenerate organelle.

Animals↗
PubMed1992

Effects of anticoagulant and autoanalyzer on blood biochemical values of loggerhead sea turtles (Caretta caretta).

We evaluated the effect of anticoagulant (lithium heparin, sodium heparin, or none) and type of autoanalyzer on selected blood biochemical values of the loggerhead sea turtle (Caretta caretta). More differences were observed between the analytes in serum and those in the 2 types of plasma than were observed between the 2 types of plasma. Differences in electrolyte concentrations were not significant when plasma from sodium-heparinized blood was compared with plasma from lithium-heparinized blood. Serum is not recommended for reptilian studies because clot formation is unpredictable and because the time required for clotting may allow substantial changes in the chemical composition of the sample. For most determinants, values varied more between the 2 types of autoanalyzers than among the 3 anticoagulant treatments. These sources of variation must be considered when performing comparative studies.

Animals↗
PubMed1991

Chronic upper respiratory tract disease of free-ranging desert tortoises (Xerobates agassizii).

Seventeen desert tortoises, Xerobates agassizii, with upper respiratory tract disease were examined; thirteen were euthanatized for necropsy. Four normal control desert tortoises from a clinically healthy population were similarly evaluated. Hemoglobin and phosphorus values were significantly (P less than or equal to 0.05) lower and serum sodium, urea, SGOT, and cholesterol values were significantly higher in ill tortoises compared to controls. No significant differences in concentrations of serum or liver vitamins A and E were found between the two groups. While no significant differences were found for concentrations of lead, copper, cadmium, and selenium, the livers of ill tortoises had higher concentrations of mercury and iron. Lesions were found consistently in the upper respiratory tract (URT) of ill tortoises. In all ill tortoises dense infiltrates of lymphocytes and histiocytes obscured the mucosal epithelium and underlying glands. The mucosal epithelium was variably dysplastic, hyperplastic, and occasionally ulcerated. Electron microscopic studies revealed small (350 to 900 nm), pleomorphic organisms resembling Mycoplasma sp., in close association with the surface epithelium of the URT of ill tortoises. Pasteurella testudinis was cultured from the nasal cavity of all ill tortoises and one of four control tortoises. A Mycoplasma sp. was cultured from the nasal passageways of four ill tortoises and was ultrastructurally similar to the pleomorphic organism present on the mucosa in tissue section.

Animals↗
PubMed1990

Cutaneous fibropapillomas and renal myxofibroma in a green turtle, Chelonia mydas.

A debilitated 7 kg juvenile green turtle (Chelonia mydas mydas) with multiple ulcerated and infected cutaneous fibropapillomas was clinically evaluated and found to have a nonregenerative anemia, hypoproteinemia, hypoalbuminemia and several electrolyte abnormalities. Surgery was performed to remove the larger tumors. The turtle did not eat postsurgically, and an attempt was made to place a pharyngostomy tube utilizing endoscopy. Edematous esophageal papillae, the angulation of the gastroesophageal junction, and a S-shaped configuration of the esophagous prevented successful placement of the tube. The animal was found dead the next day and necropsied. Multiple large white firm nodules were seen bulging from both kidneys. Microscopic examination of the nodules resulted in a diagnosis of renal myxofibroma.

Animals↗
PubMed1990

Chlamydial and poxvirus infections of circulating monocytes of a flap-necked chameleon (Chamaeleo dilepis).

Of blood films examined from 170 specimens of 15 Chamaeleo spp. in Tanzania, three C. dilepis had an intracytoplasmic inclusion within monocytes. One of the lizards was maintained in captivity and was sequentially bled over a 55 day period. At 46 days, a second type of inclusion was occasionally seen within monocytes. The lizard became ill and was euthanatized on day 55. All circulating monocytes were found to have either one or both types of inclusions. Histologic examination of multiple tissues demonstrated similar inclusions within macrophages in the spleen and liver. Transmission electron microscopic examination of monocytes revealed the presence of a chlamydia-like organism and pox-like virus. These pathogens have not been reported previously in chameleons, nor has a combined infection of circulating monocytes with these two pathogens been reported for any animal.

Animals↗
PubMed1989

Initiation and ultrastructure of a reptilian fibroblast cell line obtained from cutaneous fibropapillomas of the green turtle, Chelonia mydas.

Two fibroblastic cell lines were established from explants of fibropapillomas of each of two different green turtles (Chelonia mydas). These cells, designated GTFP (Green Turtle Fibropapilloma), were subcultured approximately 30 times at 30 degrees C in Eagle's minimal essential media supplemented with 2 to 10% fetal bovine serum. The ultrastructural morphology of the cultured fibroblasts is described. The cells contained abundant rough endoplasmic reticulum, polyribosomes, and mitochondria; collagen fibrils were visible in the extracellular space. No viruslike particles or evidence of other pathogenic agents could be demonstrated by electron microscopy in any of the cultured cells examined.

Animals↗
PubMed1989

Cutaneous fibropapillomas of green turtles (Chelonia mydas).

Six juvenile green turtles (Chelonia mydas) from the Indian River Lagoon System, Florida, U.S.A., with multiple cutaneous fibropapillomas, were kept in isolation and examined over a 6-month period. Histologically, the fibropapillomas consisted of a slightly to moderately hyperplastic epidermis overlying a thickened hypercellular dermis. In the earliest lesions, ballooning degeneration was present predominantly in the stratum basale where rete ridges extended into the dermis; aggregates of mixed inflammatory cells were present around dermal vessels. As the lesions matured, they developed an arborizing, papillary pattern. More mature lesions had a less verrucous, often ulcerated surface, with the dermis composed primarily of large collagenous fascicles and relatively few fibroblasts. While numerous trematode eggs were present within dermal capillaries of a histologically similar biopsy specimen from an Hawaiian green turtle, no trematode eggs were observed in any of 28 biopsies examined from the six Florida green turtles in this study. Low stringency Southern blot hybridization and a reverse Southern blot failed to demonstrate papillomavirus DNA in any of the samples extracted. Ultrastructural evaluation of the earliest lesions demonstrated membrane-bound intracytoplasmic vacuoles within epidermal cells in the stratum basale. Similar vacuoles were also observed in the epidermal intercellular spaces and within the dermis. Occasionally, particles with electron-dense centres and measuring 155 to 190 nm were observed in these vacuoles.

Animals↗
PubMed1988

Use of halothane to maintain anesthesia induced with etorphine in juvenile African elephants.

Sixteen 3- to 5-year-old African elephants were anesthetized one or more times for a total of 27 diagnostic and surgical procedures. Xylazine (0.1 +/- 0.04 mg/kg of body weight, mean +/- SD) and ketamine (0.6 +/- 0.13 mg/kg) administered IM induced good chemical restraint in standing juvenile elephants during a 45-minute transport period before administration of general anesthesia. After IM or IV administration of etorphine (1.9 +/- 0.56 micrograms/kg), the mean time to lateral recumbency was 20 +/- 6.6 and 3 +/- 0.0 minutes, respectively. The mean heart rate, systolic blood pressure, and respiration rate during all procedures was 50 +/- 12 beats/min, 106 +/- 19 mm of Hg, and 10 +/- 3 breaths/min, respectively. Cardiac arrhythmias were detected during 2 procedures. One elephant with hypotension responded to a decrease in the concentration of halothane and IV infusion of dobutamine HCl. Alterations in systolic blood pressure, ear flapping, and trunk muscle tone were useful for monitoring depth of anesthesia. Results indicated that halothane in oxygen was effective for maintenance of surgical anesthesia in juvenile African elephants after induction with etorphine.

Anesthesia↗
PubMed1988

Bacteremia and septic arthritis in a West African dwarf crocodile.

An anorectic, adult West African dwarf crocodile was examined because of bilateral hind limb paresis. Clinical findings included multiple skin wounds, osteomyelitis of the distal portions of the right radius and ulna, severe anemia, and Serratia marcescens bacteremia. The crocodile died after a blood transfusion. At necropsy, hemorrhage in the subarachnoid space, suppurative polyarthritis, and gastric ulceration were found. Serratia marcescens and Morganella morganii were isolated from multiple tissues and body fluids. It was concluded that the bilateral paresis was caused by severe septic arthritis secondary to bacteremia, and that the crocodile died from spinal injury caused by the blood transfusion into the supravertebral vein.

Alligators and Crocodiles↗
PubMed1987

Reptiles.

Basic techniques that will allow the clinician to properly evaluate the ill reptile are discussed. How to take a complete history and a systematic approach to physical examination are emphasized. Techniques for collection of samples for clinical evaluation and selection of drugs for treating ill reptiles are reviewed briefly.

Animal Diseases↗
PubMed1986

Conjunctivitis, tracheitis, and pneumonia associated with herpesvirus infection in green sea turtles.

Fourteen juvenile (15- to 20-month-old) green sea turtles (Chelonia mydas), representative of a group of sea turtles with clinical signs of respiratory tract disease, were euthanatized and submitted for necropsy. Macroscopically, lesions included periglottal necrosis, tracheitis with intraluminal caseous and laminated necrotic debris, and severe pneumonia. Several turtles had caseous conjunctival exudate covering the eyes. Microscopically, the turtles had fibrinonecrotic inflammation around the glottal opening, tracheitis, and severe bronchopneumonia and interstitial pneumonia. In multifocal areas, periglottal and tracheal epithelial cells adjacent to areas of necrosis had hypertrophic nuclei with amphophilic intranuclear inclusions. A mixed population of primarily gram-negative microorganisms was isolated from the tracheal and glottal lesions. Attempts at viral isolation in cultures of green sea turtle kidney cells resulted in the development of cytopathic effects characterized by giant cell formation and development of intranuclear inclusions. Using electron microscopy, intranuclear viral particles (88 to 99 nm in diameter) were seen in inclusion-containing tracheal and glottal epithelial cells and infected green sea turtle kidney cells; particles were consistently seen enveloping from nuclear membranes, and mature particles (132 to 147 nm) were found in the cytoplasm. On the basis of size, conformation, location, and presence of an envelope, the particles most closely resembled those of herpes-viruses.

Animals↗