Descriptive epidemiological study of the use of antimicrobial drugs by companion animal veterinarians in New Zealand

Abstract

AIM: To describe the patterns of use of antimicrobial drugs by veterinary surgeons treating commonly presented bacterial infections in companion animals in New Zealand.

METHODS: A postal survey of 800 randomly selected companion animal veterinarians practicing in New Zealand was conducted between August and December 2008. Data were collected regarding the antimicrobials prescribed for recent cases of skin, ear and urinary tract infections; the use of culture and susceptibility testing; and veterinarian characteristics such as proportion of time spent treating companion animals and recent attendance at continuing professional development (CPD) events. Potential associations within the data were explored using extended mosaic plots and multivariable regression models.

RESULTS:Completed surveys from 393 respondents were available for analysis, providing data on systemic antimicrobial drug use for 1,799 cases of presumptive bacterial infections. The most frequently prescribed drugs were amoxicillin-clavulanic acid (864 cases, 48%), cephalexin (558, 31%), and fluoroquinolones (198, 11%). Of 359 cases of canine superficial pyoderma, 157 (44%) were treated with amoxicillin-clavulanic acid and 155 (43%) were treated with cephalexin with median reported treatment durations of 7 and 10 days, for these two drugs respectively. Culture and susceptibility tests had been used in 376 of 1,984 (19%) of all reported cases and 160 (43%) of these were suspected urinary tract infections. Practitioners that spent 100% of their time treating companion animals and who had attended a CPD course related to companion animals within the 12 months prior to completing the survey were more likely to submit a sample for culture and susceptibility testing and to prescribe longer courses of antimicrobials for the treatment of canine pyoderma than practitioners who spent less than 100% of their time treating companion animals and had not attended a CPD course in the last 12 months.

CONCLUSIONS: Broad-spectrum drugs considered by the World Health Organisation to be critically important for human health, such as fluoroquinolones and amoxicillin-clavulanic acid, are amongst the most frequently prescribed antimicrobials in companion animal medicine, and these drugs are often prescribed without submitting a sample for culture and susceptibility testing.

CLINICAL RELEVANCE: Many cases of superficial pyoderma were treated for less than the recommended duration of 21 days, which may contribute to a higher rate of recurrent pyoderma and the development of drug resistance within the causal bacteria. Veterinarians should be aware that the use of fluoroquinolones, in particular, should be based upon the results of a culture and susceptibility test.     

Imaging of intermittency in ripple-wave turbulence

The dynamics of a fluid surface filled with high-amplitude ripples were studied with a technique (diffusing light photography) that resolves the height at all locations instantaneously. Even when nonlinearities are strong enough to generate a (Kolmogorov) cascade from long wavelength (where energy is input) to shorter wavelength, the resulting turbulent state contains large coherent spatial structures. The appearance of these structures in a thermal equilibrium state (with the same average energy) would be highly improbable.     

Predatory Dinosaurs from the Sahara and Late Cretaceous Faunal Differentiation

Late Cretaceous (Cenomanian) fossils discovered in the Kem Kem region of Morocco include large predatory dinosaurs that inhabited Africa as it drifted into geographic isolation. One, represented by a skull approximately 1.6 meters in length, is an advanced allosauroid referable to the African genus Carcharodontosaurus. Another, represented by a partial skeleton with slender proportions, is a new basal coelurosaur closely resembling the Egyptian genus Bahariasaurus. Comparisons with Cretaceous theropods from other continents reveal a previously unrecognized global radiation of carcharodontosaurid predators. Substantial geographic differentiation of dinosaurian faunas in response to continental drift appears to have arisen abruptly at the beginning of the Late Cretaceous.     

Micromechanical "Trampoline" magnetometers for use in large pulsed magnetic fields

A silicon micromechanical magnetometer was constructed and successfully used in 60-tesla pulsed magnetic fields of less than 100-millisecond duration. The device is small, inexpensive to fabricate, and easy to use. It features a fast mechanical response (up to 50,000 hertz) and extremely high sensitivity yet is relatively robust against electrical and mechanical noise. Quantum oscillations in the magnetization of a 1-microgram sample of an organic superconductor, kappa-[bis(ethylenedithio)tetrathiafulvalene]2Cu(NCS)2, have been observed with this device.     

Major compositional units of the moon: lunar prospector thermal and fast neutrons

Global maps of thermal and fast neutron fluxes from the moon suggest three end-member compositional units. A high thermal and low fast neutron flux unit correlates with the lunar highlands and is consistent with feldspathic rocks. The South Pole-Aitken basin and a strip that surrounds the nearside maria have intermediate thermal and fast neutron flux levels, consistent with more mafic rocks. There appears to be a smooth transition between the most mafic and feldspathic compositions, which correspond to low and high surface altitudes, respectively. The maria show low thermal and high fast neutron fluxes, consistent with basaltic rocks.     

Platinum catalysts for the high-yield oxidation of methane to a methanol derivative

Platinum catalysts are reported for the direct, low-temperature, oxidative conversion of methane to a methanol derivative at greater than 70 percent one-pass yield based on methane. The catalysts are platinum complexes derived from the bidiazine ligand family that are stable, active, and selective for the oxidation of a carbon-hydrogen bond of methane to produce methyl esters. Mechanistic studies show that platinum(II) is the most active oxidation state of platinum for reaction with methane, and are consistent with reaction proceeding through carbon-hydrogen bond activation of methane to generate a platinum-methyl intermediate that is oxidized to generate the methyl ester product.     

Mucopolysaccharidosis type VI in a Miniature Poodle-type dog caused by a deletion in the arylsulphatase B gene

Abstract

AIM: To investigate and characterise an inborn error of metabolism in a dog with skeletal and ocular abnormalities.

METHODS: A 2.5-year-old small male Miniature Poodle-like dog was presented with gross joint laxity and bilateral corneal opacities. Clinical examination was augmented by routine haematology, serum chemistry, radiographs, pathology, enzymology and molecular genetic studies. Euthanasia was requested when the dog was 3 years of age because of progressively decreasing quality of life.

RESULTS: Radiology revealed generalised epiphyseal dysplasia, malformed vertebral bodies, luxation/subluxation of appendicular and lumbosacral joints with hypoplasia of the odontoid process and hyoid apparatus. These clinical and radiographic findings, together with a positive urinary Berry spot test for mucopolysaccharides, and metachromatic granules in leucocytes, were indicative of a mucopolysaccharidosis (MPS), a lysosomal storage disease. Histological lesions included vacuolation of stromal cells of the cornea, fibroblasts, chondrocytes, macrophages and renal cells. The brain was essentially normal except for moderate secondary Wallerian-type degeneration in motor and sensory tracts of the hind brain. Dermatan sulphate-uria was present and enzymology revealed negligible activity of N-acetylgalactosamine-4-sulphatase, also known as arylsulphatase B, in cultured fibroblasts and liver tissue. A novel homozygous 22 base pair (bp) deletion in exon 1 of this enzyme's gene was identified (c.103_124del), which caused aframe-shift and subsequent premature stop codon. The “Wisdom pure breed-mixed breed” test reported the dog as a cross between a Miniature and Toy Poodle.

CONCLUSIONS: The clinicopathological features are similar to those of MPS type VI as previously described in dogs, cats and other species, and this clinical diagnosis was confirmed by enzymology and molecular genetic studies. This is an autosomal recessively inherited lysosomal storage disease.

CLINICAL RELEVANCE: The prevalence of MPS VI in Miniature or Toy Poodles in New Zealand and elsewhere is currently unknown. Due to the congenital nature of the disorder, malformed pups may be subject to euthanasia without investigation and the potential genetic problem in the breed may not be fully recognised. The establishment of a molecular genetic test now permits screening for this mutation as a basis to an informed breeding policy.     

Serological characterisation of Haemophilus parasuis isolates from Australian pigs

A total of 31 isolates of Haemophilus parasuis obtained from Australian pigs were serotyped by the Kielstein-Rapp-Gabrielson scheme. The isolates were assigned to serovar 1 (1 isolate), serovar 2 (1 isolate), serovar 4 (4 isolates), serovar 5 (7 isolates), serovar 9 (2 isolates), serovar 10/7 (4 isolates), serovar 12 (1 isolate) and serovar 13 (6 isolates). The remaining 5 isolates could not be assigned to a serovar. Two different serovars (5 and 13) were detected in one herd. The only 2 isolates obtained from clinically normal pigs (from the same herd) were serovar 9. The common serovars were isolated from pigs with pneumonia as well as from pigs with conditions of the Glässer's disease type. The serological heterogeneity amongst Australian isolates of H parasuis has important implications for the use of vaccines to control Glässer's disease.     

Transient glucose malabsorption in two horses fact or artefact?

Two horses, presented for investigation of chronic weight loss despite normal to increased feed intake, had flat oral glucose absorption curves, suggesting malabsorption. The cause of the apparent malabsorption was not evident grossly or on light microscopic examination of the intestinal tract. Both horses survived long term and at follow-up examination had regained weight and their capacity to absorb glucose. These cases illustrate that flat glucose absorption curves may occur in horses with no obvious intestinal lesions, that they may revert to normal and that the results of these tests should be interpreted with caution.