Seasonal reproductive characteristics of female and male Jackson's hartebeest (Alcelaphus buselaphus jacksoni).

This project examined reproductive characteristics of female and male Jackson's hartebeest (Alcelaphus buselaphus jacksoni), a subspecies that originates in Africa and is currently a model for studies of endangered hartebeest subspecies. Progestagen concentrations were measured in fecal samples collected thrice weekly for 1 year from three non-pregnant, adult females, in the Northern Hemisphere (31 degrees 37'N, 81 degrees 09'W). When their ovaries were active, the females exhibited regular luteal cycles with an overall mean (+/-S.D.) cycle length of 21.4+/-4.1 days (n=31 luteal phases). Peak luteal progestagen concentration was 1.73+/-0.63 microg/g, with a nadir concentration of 0.79+/-0.24 microg/g. Cyclic activity ceased from 6 April to 28 June, 7 April to 8 July, and from 18 February to 20 August, for the three females, respectively. During this acyclic period, mean progestagen concentration was 0.90+/-0.23 microg/g. Ejaculates were collected by electroejaculation from seven males throughout all seasons, with mean (+/-S.D.) 40+/-18% motility, 4.1+/-0.19 progressive motility (scale, 0-5), 1373+/-826x10(6) sperm/mL, and 42+/-28% morphologically normal sperm. These data characterized basic reproductive traits for Jackson's hartebeest and established the females as spontaneously ovulating and seasonally polyestrous when housed in the Northern Hemisphere, whereas males produced apparently viable sperm throughout the year.

A new species of Isospora Schneider, 1881 (Apicomplexa: Eimeriidae) from the Bali (Rothschild's) mynah Leucopsar rothschildi (Passeriformes: Sturnidae), and comments concerning the genera Atoxoplasma Garnham, 1950 and Isospora.

A new species of isosporan (Apicomplexa: Eimeriidae) is reported from the Bali mynah Leucopsar rothschildi (Passeriformes: Sturnidae). Oöcysts of Isospora rothschildi n. sp. are spherical to subspherical, 22.3 x 21.6 (20-26 x 19-23) microm, with a shape index (length/width) of 1.03 (1.00-1.15). A micropyle and oöcyst residuum are absent, but one to many polar granules are present. Sporocysts are ovoidal, 15.9 x 10.6 (15-18 x 9.5-11) microm, with Stieda and substieda bodies and a shape index of 1.50 (1.39-1.65). Each sporocyst contains an ellipsoidal sporocyst residuum, 8.0 x 5.8 (6-11 x 5-8), and each sporozoite contains two refractile bodies. No correlation was found between the presence of coccidian oöcysts in the faeces of some of the birds and Atoxoplasma in blood smears.

Trombiculid mites (Hannemania sp.) in canyon tree frogs (Hyla arenicolor).

Six wild-caught, captive canyon tree frogs (Hyla arenicolor) purchased as a group and housed at the North Carolina Zoological Park were diagnosed with intradermal Hannemania mites, the first described infestation of this frog species by this mite. Typical gross lesions were orange-colored skin vesicles approximately 1 mm in diameter, predominantly located on the ventrum and ventral hind limbs. The larval mites had ovoid bodies approximately 44 microm in length and 240 microm in width. Three of the frogs died, and three became free of mites and pathologic changes after approximately 28 wk of treatment with transcutaneous ivermectin and manual mite removal. The frogs remained free of mites at a 1-yr recheck.

Trypanosoma cruzi infection of free-ranging lion-tailed macaques (Macaca silenus) and ring-tailed lemurs (Lemur catta) on St. Catherine's Island, Georgia, USA.

Free-ranging Old World primates released on St. Catherine's Island, Georgia (USA), were tested for infection with Trypanosoma cruzi as part of a study of the epizootiology of sylvatic T. cruzi in the southeastern USA. The parasite was observed in liver infusion tryptose medium cultures of blood from seven of 11 lion-tailed macaques (Macaca silenus) and one of 19 ring-tailed lemurs (Lemur catta). Cultures of blood from 10 black and white ruffed lemurs (Varecia variegata) were all negative. Analysis of small subunit ribosomal RNA gene polymorphisms detected using polymerase chain reaction techniques indicates that the parasites isolated from both the lion-tailed macaques and the ring-tailed lemur are probably the same as T. cruzi parasites isolated from raccoons (Procyon lotor) trapped on St. Catherine's Island and other locations in the southeastern USA. Foraging lion-tailed macaques were observed to handle and partially consume specimens of Triatoma sanguisuga, the triatomine bug thought to be a vector of T. cruzi in the southeastern USA. Oral transmission of the parasite may have occurred as a result of this behavior.

Epicardial keratinaceous cyst in a tawny frogmouth (Podargus strigoides plumiferus).

Tissues from a tawny frogmouth that died acutely in a zoo collection were submitted for histopathologic examination. A small yellow nodule was observed grossly on the ventricular wall by the zoo veterinarian during collection of tissues. Histologically, the epicardial nodule consisted of a well-circumscribed, thinly encapsulated cyst, 4 mm in diameter. The cyst was composed of gradually keratinizing, attenuated, stratified squamous epithelium, one to three cell layers in thickness. The cyst was filled with laminated keratin and a few keratinized epithelial cells. The cyst was separated from the myocardium by a thin layer of adipose tissue. Based on these observations, the structure was diagnosed as an epicardial keratinaceous cyst.

Diagnosis of polyomavirus infection in seedcrackers (Pyrenestes sp.) and blue bills (Spermophaga haematina) using DNA in situ hybridization.

Avian polyomavirus (APV) infection was diagnosed in a closed research colony of seedcrackers (Pyrenestes sp.) and blue-bills (Spermophaga haematina) using DNA in situ hybridization. The DNA probe was a 1-kbp double-stranded PCR-generated probe that recognized a conserved nucleotide sequence within the VP-1 gene. Using this technique, APV infection was diagnosed, in 25 of 45 birds based upon examination of formalin-fixed paraffin embedded tissues. Birds infected with APV apparently had a higher incidence of hepatic necrosis, hepatitis, bacterial infections and parasitism than did birds without APV.

Acyclovir (Zovirax) pharmacokinetics in Quaker parakeets, Myiopsitta monachus.

The pharmacokinetics of intravenous (i.v.) and intramuscular (i.m.) single-dose administration of acyclovir were determined in Quaker parakeets. After i.v. injection at a dose of 20 mg/kg of acyclovir, elimination half-life was estimated at 0.65 h, volume of distribution at steady state was 627.65 ml/kg, and clearance was 11.22 ml/kg/min. The estimated pharmacokinetic values after i.m. injection at a dose of 40 mg/kg of acyclovir were an elimination half-life of 0.71 h and a bioavailability of 90.1%. The peak plasma acyclovir concentration occurred at 15 min when the drug was administered i.m. Plasma concentrations of acyclovir were undetectable 4-6 h after i.v. administration and 6-8 h after i.m. administration. Oral (capsules) and intravenous (sodium salt) formulations of acyclovir were given by gavage at 80 mg/kg. Peak concentrations with the sodium salt formulation were lower and developed more slowly than with the capsules. In studies designed to detect excessive drug accumulation or adverse side effects, acyclovir was administered i.m. at 40 mg/kg every 8 h for 7 days. Plasma concentrations were determined 15 min after (peak) and just prior to drug administration (trough). In another study acyclovir was gavaged at a dose of 80 mg/kg every 8 h for 4 days. Acyclovir plasma concentrations were determined just prior to and 2 h after drug administration. In both experiments, the birds maintained normal appetite and weight and did not exhibit excessive drug accumulation. Acyclovir plasma concentrations ranging from 2.07 +/- 1.09 micrograms/ml to 3.93 +/- 1.13 micrograms/ml were maintained for 4 days when acyclovir was administered in the feed and water (sole source of food and water).(ABSTRACT TRUNCATED AT 250 WORDS)

Efficacy of acyclovir against herpesvirus infection in Quaker parakeets.

We evaluated the efficacy of acyclovir against experimentally induced herpesvirus infection (Pacheco's parrot disease) in Quaker parakeets. Thirty-two of 40 birds were challenge-exposed with 0.1 ml of a suspension of herpesvirus (10(4) median cell culture infective doses [CCID50]) given IM. Treatment with acyclovir was started 24 hours later and was continued for 7 days. The birds were allotted to 5 groups of 8 birds each. There was a considerable difference in mortality between groups 1-5. Of 8 bird in each group, 6 died in group 1 (control), 1 died in group 2 (gavage), 3 died in group 3 (low dose, IM), 4 died in group 4 (high dose, IM), and none died in group 5 (contact controls). There was a significant (P = 0.023) difference in mortality between groups 1 and 2, thus the oral form of acyclovir administered by gavage was the most efficacious therapeutic regimen. Clinical signs and death occurred after discontinuation of acyclovir in groups 2 and 3, whereas the mean time of death for the control group was 6 days after challenge exposure. Herpesvirus was recovered by inoculation of chick embryo cell culture with pooled tissue suspensions from all birds that died. Histologic evidence of herpesvirus infection was found in most birds that died, with the control group having the most severe lesions. Surviving Quaker parakeets were transferred to cages with seronegative Quaker parakeets with no known exposure to herpesvirus. There have been no deaths attributable to herpesvirus infection in a period exceeding 2 years.

Medical and surgical management of benign prostatic hyperplasia, diskospondylitis, and penile paresis in an ocelot.

Benign prostatic hyperplasia, diskospondylitis at the T13-L1 intervertebral disk space, and penile paresis were diagnosed in a 16-year-old male ocelot. Treatment consisted of castration for the benign prostatic hyperplasia and long-term administration of antibiotics for the diskospondylitis. On physical examination 8 weeks after initial referral, the prostate gland was no longer palpable and could not be visualized radiographically or ultrasonographically. The diskospondylitis lesion was found to be healing, on the basis of radiographic results.

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.