Recurrent spinal arachnoid cyst in a cat

Spinal arachnoid cysts (SACs) are uncommon expanding lesions in the spinal canal. They are rarely diagnosed in dogs, and there are only four published cases in cats. We report a case of a 12-year-old cat with recurrent signs of intermittent urinary incontinence and hind limb ataxia 2 years after surgical marsupialisation of a spinal arachnoid cyst at T11/12. Recurrence of a cyst was diagnosed by myelography. Repeated marsupialisation after laminectomy was successful and the cat recovered satisfactorily although intensive physical therapy was necessary. SACs are very rare in cats and seem to occur mainly as a secondary lesion to spinal and meningeal trauma or irritation due to bony changes of the vertebrae.     

Reproductive ability of triploid ornamental (koi) carp (Cyprinus carpio L.) × goldfish (Carassius auratus L.) hybrids and characteristics of their offspring

The purpose of this study was to investigate reproductive ability of backcross triploid koi (Cyprinus carpio L.) × goldfish (Carassius auratus L.) hybrids. These triploids have been obtained by crossing of F₁ hybrid females producing diploid eggs with males of parental species. Triploid hybrid females, when crossed with goldfish or koi males, produced mostly aneuploid fish with ploidy range from approximately 2.2n–3.2n with a mean value 2.5n; some fish in crosses of triploid females with koi males were tetraploid (4.0n). Since analysed fish had in their genomes one haploid set from parental males, the data indicate that triploid hybrid females mostly produced aneuploid eggs with ploidy range from approximately 1.2n–2.2n and a mean ploidy around 1.5n while some eggs were triploid. Triploid hybrid males were completely sterile and have not released any sperm after hormonal injection. Despite their low viability, some aneuploid fish obtained from triploid hybrid females were raised in indoor recirculating systems until the age of 2 years and their reproductive ability has been evaluated. One aneuploid female with ploidy 2.1n produced larvae with ploidy range from 2.9n to 3.4n with a mean ploidy of 3.1n when crossed with a koi male; about 60% of obtained larvae had ploidy from 3.0n to 3.2n. These data indicate that this female produced mostly eggs with unreduced ploidy level.     

Reproductive ability of second generation ornamental (koi) carp (Cyprinus carpio L.) × goldfish (Carassius auratus L.) hybrids and characteristics of their offspring

The purpose of this study was to investigate the reproductive ability of second generation (F₂) koi (Cyprinus carpio L.) × goldfish (Carassius auratus L.) hybrids. Only diploid F₂ males and females were fertile and used in crosses. A significant increase was recorded in male fertility in F₂ versus F₁. In contrast with an earlier study in which only one fertile F₁ male was found, about 20% of F₂ males produced sperm. The observed reproductive ability of F₂ hybrids was similar to that demonstrated by the only fertile F₁ male and F₁ females. F₂ males produced diploid spermatozoa and generated triploids when crossed with koi females. All triploid fish in these progenies were males indicating that F₂ males had a sex chromosome constitution of XY. F₂ females produced diploid eggs and generated mostly triploids when crossed with koi males. In progenies obtained by crosses of F₂ males with F₁ and F₂ females, most of the surviving juveniles (63%–100%) were diploid; a minority of juveniles were aneuploid (ploidy ranged from 2.1n to 3.6n). Diploid fish in these progenies were presumably the result of spontaneous androgenesis and gynogenesis, by the same mechanisms observed earlier in progenies obtained by crossing the F₁ male with F₁ females.     

Pathophysiology of excessive iron storage in mynah birds

Hepatic iron overload was diagnosed in young and adult Rothschild's mynah birds. By light microscopic evaluation, it was determined that there was progressive accumulation of iron pigment with age in the hepatocytes. The Kupffer's cells of the liver, the reticuloendothelial cells of the spleen, and the phagocytic cells in the small intestine were negative for Prussian blue (iron) pigments. These observations suggested that diet had only a minor influence on the iron distribution in the mynah birds. This was confirmed by comparing iron distribution in the liver and spleen of mynah birds with that in other exotic birds receiving the same diet as the mynah birds. The syndrome of excessive iron overload in the mynah birds shared most of the important histopathologic characteristics with idiopathic (hereditary) hemochromatosis in human beings.     

Pharmacodynamics and pharmacokinetics of orally administered bishydroxycoumarin in the goat

Eight goats, 2 nontreated controls and 6 treated, were used to study the pharmacodynamics and pharmacokinetics of bishydroxycoumarin. In 5 of the 6 treated goats, there was a significant relationship between prothrombin times and drug concentrations. Activated clotting times did not change with time in either the controls or the treated goats. Five of 6 treated goats reached a plateau of drug concentration after 24 to 36 hours. Lag times for onset of pharmacologic effect ranged from 12 to 24 hours. The one goat (No. 3) that did not respond in concert with the other 5 was extremely nervous and became anorectic during the period of indoor confinement.     

Quantitative studies of erythropoiesis in the clinically normal, phlebotomized, and feline leukemia virus-infected cat

Erythropoiesis was evaluated in 5 cats at base line with normal PCV and then in the same cats with anemia induced by phlebotomy and in 5 other cats with nonregenerative anemia from community-acquired feline leukemia virus (FeLV) infection. The hematologic evaluation included complete blood cell and reticulocyte counts, marrow morphologic features, determination of serum erythropoietin concentrations by radioimmunoassay, ferrokinetic studies, and in vitro marrow culture of early erythroid progenitors (erythroid burst-forming units; BFU-E) and late erythroid progenitors (erythroid colony-forming units; CFU-E). Phlebotomized cats developed marrow erythroid hyperplasia and an increased reticulocyte count. Ferrokinetic studies revealed an increase in plasma iron turnover from 1.4 to 3.8 mg of Fe/dl of blood/day and RBC use from 50.4% to 78.5%. The mean CFU-E number and CFU-E/BFU-E ratio increased after phlebotomy, but the increase was not significant (P greater than 0.05). Serum erythropoietin values did increase significantly. In FeLV-infected cats, a nonregenerative anemia was demonstrated by marrow erythroid hypoplasia and a low total reticulocyte count. An increased percentage of rubriblasts and prorubricytes was observed in 4 of the 5 cats. Although serum erythropoietin values were high (321 +/- 123 mU/ml vs normal 14 +/- 1 mU/ml), ferrokinetic data revealed decreased erythropoiesis. Marrow culture studies in the FeLV-infected cats also revealed low numbers of BFU-E and CFU-E, but normal numbers of granulocyte-macrophage progenitors remained. Seemingly, the FeLV infection impaired the ability of feline marrow to respond physiologically to anemia.