Use of sodium monoiodoacetate to fuse the distal hock joints in horses

SUMMARY Intra-articular injection of sodium monoiodoacetate (MIA) was investigated as an agent for chemical arthrodesis of the distal hock joints in the horse. Five horses diagnosed with either spavin (three horses), a small tarsal bone fracture or a failed surgical arthrodesis, had 150 mg of MIA injected into the tarsometatarsal (TMT) joint of the affected hock(s). Eight joints were treated in the five horses. Follow-up evaluation by clinical and radiological examination took place over 9 to 14 months. Two of the five horses were sound at the conclusion of the study and one horse, although lame after flexion, was considered by the owner to have been treated successfully. One of eight TMT joints showed complete radiographic fusion. Complications after treatment included pain, chronic lameness and swelling. It was concluded that chemical arthrodesis using this technique can not be recommended as being a superior treatment as compared with surgical arthrodesis at this time but is deserving of further clinical evaluation.     

Contagious ecthyma in the live sheep export industry

Objective: To investigate control options for contagious ecthyma (scabby mouth) in Australian sheep exported live to the Middle East.
Design: Prevalence, vaccination and modelling studies.
Procedure: One hundred and forty weaner sheep (less than 1 year old) on each of 106 farms in Western Australia (WA) and 18 farm groups of adult wethers received at a WA commercial feedlot were examined for lesions of scabby mouth. Sheep on a total of 26 farms in 3 States were divided into treatment and control groups for the vaccination study. A simple deterministic compartmental model was developed to establish which parameters had the greater effect on disease prevalence.
Results: The proportion of farms with evidence of scabby mouth in weaner sheep was 23.6% and, on those farms with the disease, the overall prevalence was 6.1%. At the feedlot, 4 out of 18 farm groups had 5 or more sheep with lesions on arrival. The overall prevalence in the 4 diseased groups was 5.2%. Sheep vaccinated on farm before trucking to the feed-lot had a lower prevalence of scabby mouth at the end of simulated shipping than controls. The main determinant of scabby mouth prevalence was the proportion of sheep immune to the disease.
Conclusion: A program of vaccination for scabby mouth will reduce the prevalence of disease during live export. However, using current technology it is not possible to deliver shipments of sheep to the Middle East that are guaranteed completely free of scabby mouth.     

Policies for the vaccination of cats and dogs in New Zealand veterinary practices

AIMS: To determine current practices and attitudes towards vaccination of dogs and cats of veterinarians in New Zealand; the methods used for informing clients on which vaccines to use, and the preferred site for vaccination of cats.

METHODS: A postal questionnaire was sent to all 483 listed veterinary practices in New Zealand during February 2012. Some questions were specific to pet dogs, cats, or working farm dogs. Responses were categorised according to practice type and geographical region of the respondent. Factors associated with respondent recommendation of annual vaccination with modified live viral (MLV) vaccines were examined using logistic regression analysis. Vaccines that were considered to be essential for every animal were defined as core; those that may be recommended for animals whose location or lifestyle placed them at risk, were defined as non-core.

RESULTS: There were 204 useable returns, equivalent to a response rate of 42.2%, distributed across the country. Annual vaccination with MLV vaccines of dogs was recommended by 54/198 (27.3%) respondents, and of cats by 107/181 (59.1%) respondents. Factors associated with the recommendation of annual administration of MLV vaccines to dogs included being a companion animal practice, a desire for policies on vaccination to be left to individual clinics, and having one veterinarian in the practice. Administration of the final vaccination for puppies was recommended at ≥14 weeks old by 55/185 (29.7%) respondents, and for kittens at ≥13 weeks old by 42/183 (23%) respondents. Of respondents that administered MLV vaccines annually, 62/103 (60.2%) believed reducing the frequency of vaccination would reduce income, and 52/103 (50.5%) considered it would have a negative effect on animal health. Advice to enable clients to decide which non-core vaccines were administered was given by 181/199 (91%) respondents. Factors considered when recommending a vaccine included consideration of risk to individual patients (190/203; 93.6%), requirements of boarding kennels/catteries (165/203; 81.3%) and clinic vaccination policy (142/203; 70%). The preferred site for administering MLV vaccines to cats was the dorsal neck or inter-scapular region (137/198; 69.2%). Amongst respondents, 18 wanted disease surveillance information to allow for truly informed decisions to be made about vaccination.

CONCLUSIONS AND CLINICAL RELEVANCE: Veterinarians can now compare their own vaccination practices and attitudes with those of veterinarians nationally, and internationally. There is a need for national surveillance information and for continued education of the public and commercial kennel and cattery owners for optimal vaccination strategies to be developed.     

Infestation of sheep with the stored product mite Sancassania berlesei (Acaridae)

A sheep reared outdoors in Victoria was found to be heavily infested with a stored product mite, Sancassania berlesei (Acaridae), apparently subsequent to an earlier flystrike. Laboratory observation revealed the infestation to be self-sustaining. Shearing rapidly resolved the infestation but treatment with diazinon was ineffective. The infestation could be transferred to other sheep only in the presence of moisture; once established it caused an extensive skin lesion with considerable fluid loss, apparently contributing to the death of one animal. This lesion was extremely attractive to blowflies. Animals infested with mites showed few signs of irritation.     

Use of carbendazim and carbendazim-resistant yeasts to create different yeast densities on wheat leaves for field studies on biological control

Phyllosphere yeasts may play an important role in suppressing necrotrophic pathogens. In a randomized block design, yeast densities on flag leaves and second leaves of field-grown wheat were left unchanged (D), or were lowered by sprayings with carbendazim (A), or were raised by sprayings with a mixture ofSporobolomyces roseus, Cryptococcus laurentii var.flavescens and nutrients (B), or with carbendazim, carbendazim-resistantS. roseus andC. laurentii var.flavescens and nutrients (C). The application of carbendazim to plots A and C would avoid a biased interference of carbendazim due to other effects than reducing the natural yeast population. Prolonged differences in yeast density would be reflected in differences in severity of diseases caused by carbendazim-insensitive necrotrophic pathogens.Both treatments B and C enhanced the yeast density about 10-fold at the beginning of leaf colonization, 2 to 3 weeks after leaf emergence. Untreated leaves (D), however, were rapidly leaves. Initially, the yeasts were suppressed by carbendazim (A). However, progressively the yeast population consisted of carbendazim-resistant strains which made the carbendazim sprayings ineffective. Therefore, the substantial differences in yeast density were of limited duration. The effect of the treatments on naturally occurringMycosphaerella graminicola (anam.Septoria tritici), Puccinia recondita f. sp.tritici and the total necrotic leaf area (D-value) is discussed.Samenvatting Fyllosfeergisten kunnen misschien een belangrijke rol spelen in de onderdrukking van necrotrofe pathogenen. In een blokkenproef werd de dichtheid van gisten op vlagbladeren en tweede bladeren niet beïvvloed (D) of verlaagd door bespuitingen met carbendazim (A), of verhoogd door bespuitingen met een mengsel van gisten (Sporobolomyces roseus enCryptococcus laurentii var.flavescens en voedingsstoffen (B), of met een mengsel van carbendazim, carbendazim-resistenteS. roseus enC. laurentii var.flavescens en voedingsstoffen (C). De grootste verschillen in dichtheden van de gistpopulaties werden verwacht tussen de behandelingen A en B of C. Door alle veldjes A en C met carbendazim te behandelen wordt een eenzijdig effect van carbendazim, berustend op andere eigenschappen dan de onderdrukking van de natuurlijke gistpopulatie, voorkomen. Langdurige verschillen in de populatiedichtheden van de gisten zouden weerspiegeld kunnen worden in verschillen in aantasting door carbendazimongevoelige necrotrofe pathogenen.Aan het begin van de bladkolonisatie door gisten, 2 tot 3 weken na het verschijnen van het blad, leidde zowel behandeling B als C tot, een 10-voudige verhoging van de gistdichtheid. De onbehandelde bladeren (D) werden echter spoedig door de van nature voorkomende gisten gekoloniseerd en het verschil tussen de onbehandelde en met gist bespoten bladeren werd snel kleiner. Aanvankelijk werden de gisten door carbendazim (A) onderdrukt. Geleidelijk bestond de gistpopulatie echter uit carbendazim-resistente stammen, zodat de carbendazim bespuitingen nauwelijks meer effect hadden. Hierdoor werden grote verschillen in gistdichtheden niet langdurig gerealiseerd. Het effect van de behandelingen op de natuurlijke infectie doorMycosphaerella graminicola (anam.Septoria tritici), Puccina recondita f. sp.tritici en op het totale dode bladoppervlak (D-waarde) wordt besproken.     

Macrocyclic lactone toxicity due to abamectin in farm dogs without the ABCB1 gene mutation

Abstract

CASE HISTORY: A 5-year-old entire female Huntaway from a sheep and beef farm was one of four dogs that developed clinical signs including hypersalivation, depression, blindness and ataxia after the death of another dog. A 4-year-old female Huntaway farm dog from a second farm was observed to be sitting down more often than usual on the day after being fed part of a calf carcass that had been treated with an abamectin pour-on.

CLINICAL FINDINGS: The first dog was ataxic and depressed but did respond to sound. The second dog presented with an acute onset of blindness, mydriasis, absence of a menace response, hypersalivation, gait abnormalities (e.g. high stepping gait and ataxia), and depression. Other presenting signs included muscle tremors, dehydration and difficulty eating. No abnormalities were detected from routine haematology and biochemistry. Analysis of samples of plasma from both dogs revealed concentrations of abamectin of 0.149 mg/L and 0.260 mg/L for the first and second dogs, respectively. Buccal swabs taken from the first dog for DNA testing for the ABCB1 gene mutation, gave a negative result.

DIAGNOSIS: In addition to the presenting signs which suggested a toxicosis, both dogs had measurable concentrations of abamectin in plasma confirming exposure.

CLINICAL RELEVANCE: Farm dogs exposed to concentrated pour-on products containing abamectin have been poisoned and recover or die. The product labels do not carry any warnings as to the risk of poisoning to dogs. This paper discusses two incidents affecting six farm dogs, but the authors are aware of more toxicoses in farm dogs exposed to abamectin.     

Advances in biosecurity to 2010 and beyond: Towards integrated detection,analysis and response to exotic pest invasions

In order to limit the number and impact of exotic pest invasions, leading-edge technologies must be embraced and embedded within integrated national and international biosecurity systems. Outlined here are recent advances in the detection of exotic pests, and prospects for the early recognition of disease. Applications of new tools are described, using our understanding of the genomes of pathogens and vectors. In addition, the role of mathematical and simulation models to aid both biosecurity planning, and decision making in the face of an epidemic, are discussed, and recent attempts to unify epidemiology and evolutionary dynamics are outlined. Given the importance of emerging diseases and zoonoses, the need to align human and veterinary surveillance within fully integrated systems is underlined.