Chloramphenicol toxicosis in cats

Six cats were given chloramphenicol orally at the dose level of 120/mg/kg/day in 3 divided doses for 14 days and were then observed for another 3 weeks after treatment. Five other cats were used as untreated controls for the first 14 days and subsequently were given 60 mg of chloramphenicol/kg/day for 21 days. Clinical signs of toxicosis, which were more severe in cats given the higher dose level, included central nervous system depression, dehydration, reduced food intake, body weight loss, sporadic diarrhea, and vomiting. In cats given the higher dose level, chloramphenicol caused reversible marrow suppression, with marrow hypoplasia, maturation arrest of erythroid cells, and inhibition of mitotic activity, and caused vacuolation of lymphocytes and of early myeloid and erythroid cells. Significant changes were evident in bone marrow after treatment for 1 week and in peripheral blood at the end of the 2nd week. Hematologic changes included decreased numbers of neutrophils, lymphocytes, reticulocytes, and platelets. In cats given the lower dose level, changes in blood and bone marrow were similar but less severe.     

Effects of recombinant canine granulocyte colony-stimulating factor on white blood cell production in clinically normal and neutropenic dogs.

Recombinant canine granulocyte colony-stimulating factor (rcG-CSF) was administered to clinically normal dogs, cyclic-hematopoietic dogs, and dogs undergoing autologous bone marrow transplantation, to determine whether rcG-CSF could be used to stimulate WBC production and function in normal and neutropenic dogs. To the normal dogs, rcG-CSF was administered by SC injection at rates of 1 microgram/kg of body weight, q 12 h; 2 micrograms/kg, q 12 h; or 5 micrograms/kg, q 12 h. A significant dose-dependent increase in the WBC count resulted from the stimulation of bone marrow progenitor cells. The increased WBC count was characterized by mature neutrophilia and monocytosis. Neutrophil myeloperoxidase and phagocytic activity were normal in rcG-CSF-treated normal dogs, demonstrating the production of normal functional neutrophils in response to rcG-CSF treatment. Recombinant canine G-CSF prevented neutropenia and associated clinical signs but did not completely eliminate the cycling of neutrophils in cyclic-hematopoietic dogs when it was administered at rates of 1 microgram/kg, q 12 h, and 2.5 micrograms/kg, q 12 h. The time to bone marrow reconstitution was not decreased in dogs treated with rcG-CSF at a rate of 2.5 micrograms/kg, q 12 h, for 13 days following autologous bone marrow transplantation. On the basis of our findings, we suggest that treatment with rcG-CSF is an effective way to stimulate myelopoiesis in dogs, but that the dose of rcG-CSF required to stimulate WBC production will vary depending on the cause of neutropenia. Recombinant canine G-CSF should be useful in stimulating production and maintaining function of WBC for treatment of clinical diseases seen commonly in veterinary practice.     

Systemic toxicosis associated with azathioprine administration in domestic cats.

Five cats were treated with an azathioprine suspension (2.2 mg/kg of body weight on alternate days) and 2 cats were given vehicle (controls) for 9 weeks. Complete blood and platelet counts and serum biochemistry variables were monitored weekly. Bone marrow aspirates were evaluated every 3 weeks, and core bone marrow biopsy was performed at the end of the study. Profound neutropenia (less than 600 cells/microliters) was observed in all treated cats, and 1 cat developed pancytopenia. Treatment was discontinued if the WBC count was less than 3,000 cells/microliters. Four weeks after discontinuation of azathioprine, 1 treated cat again was given azathioprine at a lower dosage (1.1 mg of azathioprine/kg on alternate days) and neutropenia recurred within 2 weeks. During treatment, 3 cats developed thrombocytosis, and 2 developed thrombocytopenia. In 4 of 5 cats, neutropenia and thrombocytopenia resolved when azathioprine was discontinued. Bone marrow cytologic examination during treatment revealed reduction of the neutrophil line, with relative increase in monocytes. Core bone marrow biopsy at the completion of the study revealed hypocellular marrow with marked decrease in the myeloid series in cats given azathioprine. One of the cats that was treated with azathioprine had a hypercellular marrow with increased numbers of mature granulocytes and precursors; however, azathioprine had been discontinued 3 weeks prior to biopsy. Alterations in serum biochemical variables were not associated with azathioprine. Two cats that were treated with azathioprine developed respiratory tract infections, and 1 of them was euthanatized during the study.     

Megaloblastic erythropoiesis and tissue depletion of folic acid in the cat

Dietary requirement for folic acid was shown in the cat. Folic acid deficiency was produced by feeding young cats a deficient diet (0.125 mg of total folate/kg of dry weight by analysis) for 22 weeks. The folic acid-deficient cats grew normally, but had reduced plasma, red blood cell, and liver folate concentrations in comparison with those concentrations in cats fed a control diet (1.36 mg of total folate/kg).. Urinary excretion of formiminoglutamic acid was increased in all deficient diet cats 24 hours after L-histidine injection. Erythroblasts in bone marrow smears from folic acid-deficient cats were megaloblastic; they showed abnormal nuclear chromatin patterns and had nuclear-cytoplasmic asynchronism.     

Pharmacokinetics,efficacy prediction indexes,and residue depletion of ribavirin in Atlantic salmon's (Salmo salar) muscle after oral administration in feed

Ribavirin is an antiviral used in human medicine, but it has not been authorized for use in veterinary medicine although it is effective against infectious salmon anemia (ISA) virus, between others. In this study, we present a pharmacokinetic profile of ribavirin in Atlantic salmon (Salmo salar), efficacy prediction indexes, and the measure of its withdrawal time. To determine the pharmacokinetic profile, fishes were orally administered with a single ribavirin dose of 1.6 mg/kg bw, and then, plasma concentrations were measured at different times. From the time‐vs.‐concentration curve, Cmax = 413.57 ng/mL, T_max = 6.96 h, AUC = 21394.01 μg·h/mL, t_1/2 = 81.61 h, and K₁₀ = 0.0421/h were obtained. Ribavirin reached adequate concentrations during the pharmacokinetic study, with prediction indexes of C_max/IC₅₀ = 20.7, AUC/IC₅₀ = 1069.7, and T>IC₅₀ = 71 h, where IC is the inhibitory concentration 50%. For ribavirin depletion study, fishes were orally administered with a dairy dose of 1.6 mg/kg bw during 10 days. Concentrations were measured on edible tissue on different days post‐treatment. A linear regression of the time vs. concentration was conducted, obtaining a withdrawal time of 1966 °C days. Results obtained reveal that the dose of 1.6 mg/kg bw orally administered is effective for ISA virus, originating a reasonable withdrawal period within the productive schedules of Atlantic salmon.     

Evaluation of toxicosis of liposome-encapsulated cis-bis-neodecanoato-trans-R,R-1,2-diaminocyclohexane platinum (II) in clinically normal cats

OBJECTIVE: To determine adverse effects of single and multiple doses of liposome-encapsulated cis-bis-neodecanoato-trans-R,R-1,2-diaminocyclohexane platinum (II) (L-NDDP) administered IV to healthy adult cats. ANIMALS: 10 healthy adult cats. PROCEDURE: 8 cats were given a single dose of L-NDDP (at rates of 75, 100, 150, or 200 mg/m2), and 2 cats were given liposomal lipid (1,500 mg/m2). Six of the 10 cats were given doses of L-NDDP at the maximum tolerated dosage (100 mg/m2) or a lower dosage (75 mg of L-NDDP/m2) at 21-day intervals, for a total of 4 treatments. Hematologic and serum biochemical analyses, urinalyses, and physical examinations were used to monitor effects of L-NDDP. RESULTS: All cats had transient pyrexia, lethargy, vomiting (1 to 3 times/24 h), inappetence, and an acute species-specific infusion reaction that was prevented by administration of atropine-diphenhydramine. Dose-limiting toxicosis was evident as a 10-day course of lethargy, intermittent vomiting, and diarrhea. In cats given multiple doses, dose-related thrombocytopenia, cumulative myelosuppression, transient increased hepatic transaminase activity, and mild to moderate hepatic hydropic degeneration and proximal renal tubular lipidosis in excess of lipidosis expected for this species were detected. Bone marrow hypoplasia was detected in some cats that received higher doses (cumulative dosages of 300 or 400 mg of L-NDDP/m2). CONCLUSION: Cats can safely be given L-NDDP at potentially therapeutic dosages without inducing renal or pulmonary toxicoses. CLINICAL RELEVANCE: Because L-NDDP has better tumoricidal activity than cisplatin (in vivo and in vitro) and is not cross resistant, it may be similarly or more efficacious than cisplatin in humans and dogs.     

Use of a nonionic detergent (Triton WR 1339) in healthy cats to assess hepatic secretion of triglyceride

OBJECTIVE: To determine whether a nonionic detergent (Triton WR 1339) can be used in cats to assess hepatic secretion of triglyceride. ANIMALS: 28 healthy cats. PROCEDURE: Triton WR 1339 was administered IV according to the following schedule: 5, 50, 150, and 250 mg/kg of body weight. Control cats did not receive an injection or received 0.9% NaCl or PBS solutions at the same osmolarity and volume as the 250 mg/kg group. Blood samples were collected throughout the 48-hour period after administration for determination of triglyceride and cholesterol concentrations and for RBC morphology and osmotic fragility studies. RESULTS: Administration of Triton WR 1339 at 150 and 250 mg/kg caused profound hypertriglyceridemia. Triglyceride concentrations increased in a curvilinear fashion for the first 2 hours and remained increased for approximately 24 hours. Area under the time-concentration curve for triglyceride at 5 hours differed significantly among groups. At 12 and 24 hours, cholesterol was significantly higher in cats receiving 250 mg/kg. The most dramatic changes in osmotic fragility and RBC morphology were in cats receiving 250 mg/kg; 1 of these cats developed severe icterus and died 5 days later. Feeding rice and casein before administering Triton WR 1339 at 150 mg/kg did not appear to affect the hypertriglyceridemia response. CONCLUSIONS AND CLINICAL RELEVANCE: Triton WR 1339 can be administered IV to cats at a rate of 150 mg/kg to assess hepatic triglyceride secretion, although some cats may have increased RBC osmotic fragility. Higher dosages caused substantial adverse effects, whereas lower dosages did not alter plasma triglyceride concentration.     

Effects of heterologous antineutrophil antibody in the cat

Rabbit anti-cat neutrophil serum was injected intraperitoneally into cats to study its effects on blood neutrophil numbers, on development of neutrophils in bone marrow, and on the fate of circulating and developing neutrophils. There was a significant difference (P less than 0.05) in curves of blood neutrophil numbers between antineutrophil serum (ANS)- and normal rabbit serum (NRS)-injected cats; neutrophil counts tended to decrease in ANS-injected cats, whereas a transient increase in counts occurred in NRS-injected cats. Significant left shifts (P less than 0.05) were present in ANS-injected cats, but absent in NRS-injected cats. Toxic morphologic changes were noted in blood neutrophils in all ANS-injected cats. Significant bone marrow changes (P less than 0.05) occurred in ANS-injected cats, but were absent in NRS-injected cats. Myelocyte percentages of the granulocyte marrow population increased during the time that segmented neutrophil percentages decreased. In ANS-injected cats, the percentage of cells in the mitotic pool (myeloblasts, promyelocytes, myelocytes) significantly increased (P less than 0.05), with a corresponding significant decrease (P less than 0.05) in the postmitotic pool (metamyelocytes, bands, segmented neutrophils). Aspirated bone marrow smears (Wright's stain) revealed marrow macrophages containing phagocytized neutrophil bands and segmented neutrophils. Sections of liver obtained after cats were necropsied revealed neutrophil phagocytosis by Kupffer's cells, but neutrophil phagocytosis was not demonstrated in other tissues examined.     

Bone marrow hypoplasia in a cat treated with griseofulvin

Three weeks after initiation of griseofulvin treatment for dermatophytosis (40 mg/kg of body weight, q 12 h), an 8-yr-old domestic shorthair cat developed depression, vomiting, and pyrexia. Abnormalities found during physical examination included bilateral mydriasis, visual impairment, grade-II/V systolic murmur and multiple areas of alopecia. The cat was pancytopenic; serum biochemical abnormalities included hyperbilirubinemia, hyperglycemia, hyponatremia, and hypokalemia, and urinalysis revealed proteinuria, glycosuria, and bilirubinuria. Examination of a bone marrow aspirate revealed profound hypoplasia of all precursors. Griseofulvin toxicosis was diagnosed on the basis of the temporal relationship of drug administration with onset of clinical, hematologic, and biochemical abnormalities and failure to identify an infective or neoplastic cause for the bone marrow hypoplasia. The condition was refractory to treatment and the cat was euthanatized. Pathologic changes in the bone marrow were consistent with severe hypoplasia of all bone marrow precursors.     

Enhanced phagocytic activity of neutrophils caused by administration of egg white derivatives (EWD) in cats injected with cyclophosphamide (CPA)

To examine in vivo effects of egg white derivatives (EWD), the numbers of peripheral blood cells and neutrophil phagocytosis were evaluated in cats injected intramuscularly with cyclophosphamide (CPA). There were no changes in the number of red blood cells (RBC) or packed cell volume (PCV) values regardless of oral administration of EWD or injection of CPA, but the numbers of platelets, white blood cells (WBC) and neutrophils in cats administered EWD significantly increased (p<0.05 to 0.01) when compared with those in control cats which received saline solution. In addition, the administration of EWD resulted in a significant enhancement in the phagocytic activity of neutrophils (p<0.01) when compared to control cats, suggesting that EWD has a stimulating effect on leukocyte progenitors. The numbers of platelets, WBC and neutrophils, and the phagocytic activity of neutrophils in cats injected with CPA alone were significantly lower (p<0.05 to 0.01) than those in control cats. However, co-administration of EWD to cats injected with CPA resulted in a significant increase in the numbers of platelets, WBC and neutrophils (p<0.05 to 0.01), and in the phagocytic response of neutrophils (p<0.01) when compared to cats injected with CPA alone. Therefore, these results suggest that co-administration of EWD may be effective in reducing some possible side effects in animals treated with immunosuppressive or antitumor agents.     

Pathologic features of adriamycin toxicosis in young pigs: nonskeletal lesions

In ten experiments, 53 castrated male 4- to 8-week-old weanling pigs were given adriamycin (ADR) IV at mean dosages of 0.64, 1.0, 1.6, 3.2, or 6.4 mg/kg/week at various frequencies for up to 20 weeks. Mortalities in pigs given these dosages were 0% after 112 days, 100% after 134 days (survival time was 48 to 134 days), 91% after 75 days (survival time was 5 to 75 days), 100% after 28 days (survival time was 23 to 28 days), and 100% after 14 days (survival time was 10 to 14 days), respectively. Survival time was prolonged in younger pigs and in pigs given smaller but more frequent dosages of ADR. Characteristic gross and histopathologic alterations of ADR toxicosis were observed in pigs given 1.0, 1.6, 3.2, or 6.4 mg/kg/week mean dosages. The most frequent lesions were in the alimentary tract, myeloid and lymphoid tissues, skin, and perivascular tissues at injection sites. Alimentary tract lesions were mucosal epithelial atrophy, with secondary fibrinonecrotic inflammation in the oral cavity and large intestine. Marked hypoplasia was seen in bone marrow and lymphoid tissues, with frequent terminal hemorrhagic diathesis and septicemia. Several days before death, the pigs developed severe dermatitis over the ventral portion of the abdomen and inner surfaces of the limbs. Perivascular necrosis and cellulitis produced by extravasation of ADR was a frequent complication of treatment. Terminal severe acute pneumonia occurred in most pigs. Pericarditis or cardiomyopathy (or both) developed in 14 pigs, given 0.64, 1.0, or 1.6 mg/kg each week (mean cumulative dosage 520.5 mg/m2 of body surface). Characteristic histopathologic and ultrastructural alterations in affected cardiac muscle cells were vacuolar degeneration, myocytolysis, and hyaline necrosis. Nephrotoxicosis also was in pigs with chronic ADR toxicosis. Systemic antibiotic treatment did not prolong survival of ADR-treated pigs in two experiments, but did in one other experiment.     

Drug Efficacy of Terbinafine Hydrochloride (Lamisil®) During Oral Treatment of Cats,Experimentally Infected with Microsporum canis

Cats represent a primary source of Microsporum canis infections in humans. Terbinafine hydrochloride (Lamisil^®) is commonly used in the treatment of microsporosis in humans as its fungicidal action permits short periods of treatment. The aim of the present study was to estimate the efficacy of the drug in cats. Nine cats were experimentally infected with M. canis and treated with terbinafine hydrochloride at a dose of 10–20 mg/kg (once daily, SID; low‐dose group, LDG). Another nine cats were similarly infected and treated with 30–40 mg/kg SID (high‐dose group, HDG) and a further nine cats were also infected and left untreated (control group, CG). The general condition of the cats was observed daily and their clinical symptoms evaluated weekly. The cats recovery was monitored using the Wood's lamp illumination test and microscopic and fungal culture examinations. The general condition of the cats during the study was good. The cure rates of the LDG were not significantly different from the CG at any period during the treatment. However, the HDG cure rates differed significantly from the other two groups. After 109 days of treatment, when all nine cats of the HDG were healed, seven cats of the LDG and all the cats in the CG were still M. canis‐positive. This study shows that dosages of 10–20 mg/kg SID of terbinafine hydrochloride are not sufficient to terminate an experimental M. canis infection in cats within an acceptable period of time. Terbinafine hydrochloride can be used to treat dermatophytosis in cats, but a higher dosage, 30–40 mg/kg SID, should be used to achieve a cure.     

Tissue concentrations of clindamycin after multiple oral doses in normal cats

Eighteen normal cats were randomly allocated into two blocks with three treatment groups and dosed orally with clindamycin aqueous solution for 10 days at a dosage rate of 5.5 mg/kg twice daily (Group 1), 11 mg/kg twice daily (Group 2), or 22 mg/kg once daily (Group 3). At the end of dosing, all cats were killed and tissues were taken for clindamycin concentration analysis. Clindamycin was extracted from tissues using solid-phase extraction columns followed by microbiological assay of clindamycin using a cylinder plate assay using M. luteus. Recovery from each tissue was determined by inoculating known concentrations of clindamycin into drug-naive tissues and comparing the observed concentration from the expected concentration. Confirmation that the bioassay detected clindamycin and not N-desmethylclindamycin, its active metabolite, was done using gas-chromatography-mass-spectrometry. Concentrations were highest in the lung, with tissue:serum ratios greater than 3 in all groups. Concentrations were higher in Group 3 than Group 1 (P less than 0.05). Only liver concentrations in Group 3 were statistically higher than in Group 2, although all tissues except bone marrow and CSF had numerically higher concentrations in Group 3 than Group 2. The tissue:serum ratio was greater than 1 in all tissues studied except bone, cerebrospinal fluid, brain, and skeletal muscle.     

Serum concentrations of gentamicin in cats

Twenty-one adult cats, allotted into 2 groups, were given gentamicin sulfate at dosages of either 5.0 mg/kg of body weight or 2.5 mg/kg as a single IM injection. During a 24-hour period, serum concentrations of gentamicin were measured serially, using a fluorescence immunoassay. The mean peak serum concentration of gentamicin in cats given 5.0 mg/kg was 23.1 micrograms/ml at postinjection hour (PIH) 0.5; thereafter, the mean serum concentration steadily decreased to 2.0 micrograms/ml at PIH 24. The mean peak serum concentration for cats administered 2.5 mg/kg was 9.1 micrograms/ml at PIH 0.5; thereafter, the mean serum concentration steadily decreased to 1.3 micrograms/ml at PIH 12. Serum therapeutic concentrations, without exceeding toxic concentrations, were attained at the 2.5 mg/kg dosage.     

Evaluation of methylprednisolone and triamcinolone for the induction and maintenance treatment of pruritus in allergic cats: a double-blinded, randomized, prospective study

Background – Oral triamcinolone (T) and methylprednisolone (M) have been recommended at various dosages for the control of pruritus associated with feline allergic dermatitis. Objectives – The first objective was to determine effective dosages of methylprednisolone (Pfizer, New York, NY, USA) and triamcinolone (Boehringer Ingelheim Vetmedica, Inc., St Joseph, MO, USA) required to induce remission from pruritus associated with feline allergic dermatitis. The second objective was to compare efficacy of several different alternate day maintenance dosages. The third objective was to determine whether laboratory abnormalities occurred at effective dosages. Animals – Thirty‐two client‐owned allergic cats were randomly assigned to the M or T groups. Methods – Owners reported weekly on pruritus score and behavioural changes. Remission was defined as a pruritus score of ≤2/10, with 0 as the least and 10 as the most pruritic. Serum chemistry, complete blood count, fructosamine and urinalysis were assessed on day 0, at the end of the 7–14 day induction phase and at study completion. Results – Mean once daily doses required for induction were 1.41 mg/kg for M and 0.18 mg/kg for T. Mean alternate day maintenance doses were 0.54 mg/kg for M and 0.08 mg/kg for T. There was a statistically significant decrease in eosinophils and increase in fructosamine for both groups from baseline to study completion. Fructosamine levels did not exceed the reference range in any case. Conclusions – These results suggest that triamcinolone is approximately seven times as potent as methylprednisolone, and that these dosages are efficacious and well tolerated for the control of pruritus in allergic cats.     

A hematological study on thirteen cats with myelodysplastic syndrome

Hematological abnormalities were investigated in 13 cats with myelodysplastic syndrome (MDS). Examination of the peripheral blood samples from the 13 cats revealed anemia in 11 cats, leukopenia in 9 cats, and thrombocytopenia in 9 cats. Four cats had pancytopenia (30.8%) and 9 cats had bicytopenia (69.2%). Dysplastic changes of erythrocytes, neutrophils, and platelets in the peripheral blood were found in 5, 10 and 8 cats, respectively. Bone marrow examination of the 13 cats revealed that ratios of blast cells to all nucleated cells (ANC) ranged from 0 to 20%. Ratios of erythroid progenitor cells to ANC were more than 50% in 3 cats and less than 50% in 10 cats. Eosinophils accounted for more than 5% of non-erythroid cells in 10 cats. Dysplastic changes in the granurocytic, erythrocytic, and megakaryocytic cells in the bone marrow were found in 11, 7 and 5 cats, respectively. Dysplastic changes in these cats included giant neutrophils, ring-nucleated neutrophils, binuclear myelocytes, hypersegmented and hyposegmented neutrophils, megaloblastoid erythroblasts, multinucleated erythroblasts, micromegakaryocytes, and segmented multinucleated megakaryocytes. Virological examination indicated the presence of feline leukemia virus antigen in the peripheral blood from all of the 13 cats with MDS. The peripheral blood cytopenias and dysplastic changes in each blood cell lineage in the bone marrow were shown to be important for the diagnosis of MDS in cats.     

Plasma angiotensin converting enzyme activity and pharmacokinetics of benazepril and benazeprilat in cats after single and repeated oral administration of benazepril.HCl

The plasma pharmacokinetics of benazepril and its active metabolite, benazeprilat, were determined in cats after oral administration of benazepril.HCl at dosages of 0.25, 0.5 and 1.0 mg/kg as a single dose (n = 5 per group) and after once daily application for 8 days (n = 6 per group). Pharmacodynamics were assessed by measurement of plasma angiotensin converting enzyme (ACE) activity. After single administration of benazepril.HCl, maximum benazepril concentrations were recorded at the first sample (2 h) and declined relatively rapidly with an elimination half life (t1/2) of 1.4 h. Highest benazeprilat concentrations were recorded at the first sample (2 h) in most cats and declined biphasically with half lives of each phase of 2.4 and 27.7 h. With repeated administration, plasma benazeprilat concentrations accumulated slightly with accumulation ratios (R) of 1.46, 1.36 and 1.24 for the 0.25, 0.5 and 1.0 mg/kg dosages of benazepril.HCl, respectively (median value of 1.36 for all dosages). All three dosages of benazepril.HCl caused marked inhibition of plasma ACE activity in all cats. The maximum effect (Emax, % inhibition of ACE as compared to baseline) was > or = 98% after single and 100% with repeated administration. The duration of action of benazepril.HCl was long, with > 87% (single) and > 90% (repeat) inhibition of plasma ACE persisting 24 h after dosing. Benazepril.HCl was well tolerated in all animals. Dosages of 0.25-1.0 mg/kg benazepril.HCl once daily are recommended for clinical testing in cats.     

A randomized double-blinded placebo-controlled study to evaluate an effective ciclosporin dose for the treatment of feline hypersensitivity dermatitis

Background – Hypersensitivity dermatitides (HD) are frequently suspected in cats, but there are few clinical studies on safe and effective treatments in the published literature. Objectives – To establish a safe and effective dose of ciclosporin in the treatment of feline HD. Animals – One hundred client‐owned cats with feline HD. Methods – Double‐blind study, with cats randomly assigned to receive ciclosporin at either 7.0 mg/kg once daily (n = 33) or 2.5 mg/kg once daily (n = 32) or a placebo (n = 35) for 6 weeks. Results – Mean Total Lesion Scores with 7.0 mg/kg ciclosporin were significantly lower than with 2.5 mg/kg ciclosporin (P = 0.0047) or placebo (P = 0.0003) at study end. Individual Total Lesion Scores improved by >50% in 70% of the 7.0 mg/kg group, compared with 47% in the 2.5 mg/kg group and 23% in the placebo group (P = 0.0006). The investigators’ Global Assessment of Improvement was ‘excellent’ or ‘good’ in 61% of cats treated with 7.0 mg/kg ciclosporin, compared with 47% of cats given 2.5 mg/kg and 23% given placebo. The improvement in Investigator Pruritus Scores was significantly greater in cats treated with 7.0 mg/kg ciclosporin (54%) compared with both 2.5 mg/kg ciclosporin (32%; P = 0.0232) and placebo (21%; P = 0.0063). Mild gastrointestinal disorders were the most common adverse events, but these did not require cessation of therapy. Conclusions and clinical importance – Results suggest that 7.0 mg/kg ciclosporin once daily in food or per os for 6 weeks is effective and well tolerated in feline HD.     

Intravenous administration of docetaxel to cats with cancer

Background: The safety of IV administration of docetaxel to cats with cancer has not been reported. Objectives: Document adverse effects of IV administration of docetaxel to cats. Animals: Twenty‐one client‐owned cats with any confirmed malignancy. Methods: Cats received up to 5 docetaxel treatments, administered IV every 3 weeks. The initial dosage was 1.0 mg/kg, and dosages were increased by increments of 0.25 mg/kg in cohorts of 3 cats. Adverse events were determined by a CBC at days 7 and 21, serum chemistry and urine specific gravity at day 21, and medical histories provided by the owners. Results: Cats received docetaxel dosages ranging from 1.0 to 2.5 mg/kg, for a median of 2 treatments. Dose‐limiting toxicoses included fever, neutropenia, and vomiting, seen in 2 of the 4 cats treated at 2.5 mg/kg. Hypersensitivity reactions were infrequent (4 of the 21 cats) and mild. The maximum tolerated dosage was 2.25 mg/kg. Conclusions and Clinical Importance: Docetaxel can be administered IV to cats with a low incidence of adverse effects.     

Bone marrow hypoplasia and intestinal crypt cell necrosis associated with fenbendazole administration in five painted storks

Five painted storks were treated with fenbendazole for 5 days for internal parasitism. Four birds died following treatment. Profound heteropenia was a consistent finding in all samples evaluated; additionally, the 1 surviving bird had progressive anemia. Consistent necropsy findings in the 4 birds that died were small intestinal crypt cell necrosis and severe bone marrow depletion and necrosis. Fenbendazole has been associated with bone marrow hypoplasia and enteric damage in mammals and other species of birds. The dosages of fenbendazole used in birds are often substantially higher than those recommended for mammals, which may contribute to bone marrow hypoplasia and intestinal crypt cell necrosis associated with fenbendazole administration in birds.