Immunization against respiratory diseases in cats.

The studies we carried out on respiratory diseases concerned inactivated vaccines administered by the parenteral route and which safety and potency had been clearly established. The immunity we evidenced is a humoral general (and certainly cellular) immunity.An additional aim is under investigation: the development of a local immunity.We are working on the development of a vaccine with attenuated live virus, that may be administered by the oculo—nasal route and used in association with an inactivated vaccine.Numerous experiments are presently carried out to check the safety and potency of this live vaccine and determine the optimum scheme of vaccination.     

Long term variability of total respiratory impedance in normal ponies

Marked seasonal variations were found in the total respiratory impedance of normal Shetland ponies. A large and statistically significant increase in the magnitude of impedance was seen in August, with the maximum change occurring at 22 Hz. Acute inhalation of air at -30°C had a minimal effect on the total respiratory impedance of the ponies, suggesting that changes in air temperature were not responsible for the observed variation in impedance.     

Feline-specific serum total IgE quantitation in normal, asthmatic and parasitized cats

Immunoglobulin E (IgE) plays an important role in defense against parasitic infections as well as allergy. Knowledge of serum total IgE concentrations may have value in diagnosis and prognostication of various disorders; however, to date, no studies have reported feline serum total IgE concentrations. We hypothesize that serum total IgE concentrations will be greater in spontaneously parasitized and asthmatic cats compared to healthy pet cats. Healthy (n=10), parasitized (10) and asthmatic cats (eight) had measurement of serum total IgE by ELISA. Data were analyzed using a t-test with P<0.05 considered significant. Serum total IgE was higher in parasitized (mean±SEM, 328.4±123.8μg/ml; P<0.028) and asthmatic cats (85.5±19.5μg/ml; P<0.047) compared to healthy cats (45.9±19.6μg/ml). However, serum total IgE had poor discriminatory capability between diseased and healthy cats. In conclusion, this assay can detect small quantities of feline serum total IgE, which may be beneficial in future studies of parasitism or allergic disease.     

Erythrocyte protoporphyrin concentrations in clinically normal cats and cats with lead toxicity.

Erythrocyte protoporphyrin (EPP) and blood lead concentrations were determined in 91 clinically healthy cats living in the inner suburban area of Sydney, Australia. The mean EPP concentration was 223.4 +/- 186.1 micrograms litre-1 whole blood and the mean blood lead concentration 0.62 +/- 0.25 mumol litre-1. EPP concentrations were also monitored in three cats with confirmed lead toxicity--at the time of diagnosis and one week and one month after chelation therapy with calcium EDTA. EPP concentrations were elevated in two cats and within the normal range in the third cat at the time of diagnosis. EPP concentration were higher in two cats one week after treatment than at the time of diagnosis. One month after chelation therapy, EPP concentrations were normal in two cats but still substantially elevated in the third cat although its blood lead concentration had returned to normal and all clinical signs of lead toxicity had resolved. It was determined that the predominant form of protoporphyrin present in cats with lead toxicity was zinc protoporphyrin. The EPP assay may have limited value in the diagnosis of acute lead toxicity and in monitoring the success of chelation therapy in cats.     

Tear-film osmolarity in normal cats and cats with conjunctivitis

Objective To compare the tear‐film osmolarity of normal cats and cats with conjunctivitis. Animal studied The population consisted of shelter, research, and privately owned cats. Procedures Cats were classified as normal or having conjunctivitis. An ophthalmic examination including Schirmer tear test (STT), fluorescein staining, tear‐film break‐up time (TFBUT), intraocular pressure (IOP), and slit‐lamp biomicroscopy of the anterior segment was performed. The severity of conjunctivitis was graded and assigned a numerical score. The Tear Lab^TM Osmolarity System was utilized to determine the tear‐film osmolarity. Unpaired t‐tests were used to compare tear‐film osmolarity, TFBUT, IOP, and STT of the two groups. Results A total of 93 cats (186 eyes) were examined. There were 37 normal cats (74 eyes) and 39 conjunctivitis cats (78 eyes). The mean age was 2.34 years. There was no statistical difference (P = 0.2065) between the median tear‐film osmolarity of normal cats (328.5 ± 17.94 mOsms/L) and conjunctivitis cats (325.0 ± 24.84 mOsms/L). Cats with conjunctivitis had an accelerated TFBUT (P < 0.0001) and lower IOPs (P < 0.0001) as compared to normal cats. No statistical difference was found between STT values (P = 0.1304). Conclusions The median tear‐film osmolarity of normal cats was 328.5 mOsms/L. Despite the accelerated TFBUT, conjunctivitis did not cause a statistically significant change in tear‐film osmolarity. The Tear Lab^TM Osmolarity System was easily used and well tolerated by the cats in the study.     

Pharmacokinetics of methimazole in normal cats and cats with hyperthyroidism

The intravenous and oral disposition of the antithyroid drug methimazole was determined in 10 clinically normal cats and nine cats with naturally occurring hyperthyroidism. After intravenous administration of 5 mg methimazole, the mean residence time was significantly (P less than 0.05) shorter in the cats with hyperthyroidism than in the normal cats, but there was no significant difference between the mean values for total body clearance (CL), steady state volume of distribution (Vdss), terminal elimination rate constant (ke), or serum terminal half-life (t1/2) in the two groups of cats. After oral administration, the mean bioavailability of methimazole was high in both the normal cats (77.6 per cent) and cats with hyperthyroidism (79.5 per cent). The values for mean residence time, ke and serum terminal t1/2 after oral dosing were significantly shorter in the cats with hyperthyroidism than in the normal cats. However, after oral administration of methimazole there were no significant differences between the mean values for CL, Vdss, bioavailability and maximum serum concentrations or the time for maximal concentrations to be reached in the two groups of cats. Overall, most pharmacokinetic parameters for methimazole were not altered by the hyperthyroid state. However, the cats with hyperthyroidism did show a trend toward faster elimination of the drug compared with the normal cats, similar to what has been previously described for the antithyroid drug propylthiouracil in cats. These results also indicate that methimazole is well absorbed when administered orally and has a higher bioavailability than that of propylthiouracil in cats with hyperthyroidism.(ABSTRACT TRUNCATED AT 250 WORDS)     

Bordetella and Mycoplasma respiratory infections in dogs and cats.

The consequences of B. bronchiseptica and mycoplasma infections in dogs and cats vary greatly. Only careful clinical judgment can dictate when to institute antimicrobial and other supportive treatments. Approaches to controlling diseases caused by these organisms should be tailored to meet individual needs. Management strategies that reduce natural exposure levels in the animal's environment and maintain active immunity to contagious components of disease have the highest likelihood of success.     

Some effects of short-term methylprednisolone therapy in normal cats.

Four normal cats were treated weekly for 4 weeks with repositol methylprednisolone. Hemograms, serum chemistry panels, urinalyses, 24 hour water consumption, physical and constitutional parameters, and blood cortisol responses to ACTH stimulation were monitored before and during a day were done prior to steroid therapy on each cat. Clinicopathologic abnormalities induced by steroid therapy were, on the whole, inconsistent and minor. The most important findings were: (1) marked steroid-induced suppression of blood cortisol responses to ACTH, and (2) a circadian rhythm of blood cortisol production that was opposite to that of humans and dogs.     

Experimental drug therapy for respiratory disorders in dogs and cats.

Experimental therapy in veterinary medicine is based on empiric reasoning. If a particular therapy is labeled experimental, it means that its effectiveness has not been demonstrated scientifically. Empiric therapy is experimental and is based on experience, not on scientific proof. The purpose of this article is to suggest the use of specific experimental drug therapies for certain respiratory disorders in dogs and cats.     

Rational antibiotic therapy for respiratory disorders in dogs and cats.

Therapy of respiratory tract infections presents some unique challenges to the veterinary practitioner. These infections often involve underlying disease processes that have predisposed the patient to secondary bacterial infection and may complicate the response to therapy. Because of the diversity of microbial organisms that may colonize and invade the respiratory tract, treatment targeted at the infecting pathogens is best accomplished with bacterial culture and susceptibility testing. When these data are unavailable, rational antibiotic treatment should be based on familiarity with historical data and clinical experience. Optimal drug selection is based on predicted microbial susceptibility, drug distribution in the respiratory tract, and safety of the patient. Instituting the appropriate dosage regimen and duration of therapy maximizes the opportunity for a successful resolution of bacterial infections.