The absorption of cypermethrin in the grasshopper Melanoplus sanguinipes (Fab.): Effects of volatilisation,temperature, age,sex and parasitisation by Malameba locustae (King and Taylor)

The residues from metered doses of cypermethrin were recovered from excised portions of grasshopper cuticle to determine losses by volatilisation. Residues from similar doses were also recovered from the cuticles of intact grasshoppers and from whole body homogenates after rinsing the cuticle, to determine rates of absorption and losses from metabolism. Residues were recovered from males and females one week and three weeks after fledging in grasshoppers infected with Malameba locustae and in uninfected ones. They were maintained at 15 or 30°C and sampled from each combination of factors at 4, 8, 16, 24, 30 and 48 h after treatment. There was no measurable loss of cypermethrin by volatilisation up to 72 h after application to excised portions of cuticle at either 15 or 30°C. In all combinations of factors, more cypermethrin was recovered externally (P <0.05) from grasshoppers held at 15°C than those held at 30°C and more from infected grasshoppers than from those that were uninfected. Significantly more cypermethrin was also recovered externally from males than from females (P <0.05) and more from infected one-week-old grasshoppers than those that were three weeks old. At 15°C there was a gradual trend towards accumulation of cypermethrin internally, but at 30°C an initial trend towards accumulation was followed by one of decline. Residual cypermethrin recovered could in general be related to the negative temperature coefficient of toxicity, to a decreased sensitivity to cypermethrin in infected grasshoppers and to an increased sensitivity in older grasshoppers.     

COMPUTED TOMOGRAPHIC FINDINGS IN 24 DOGS WITH LIPOSARCOMA

Computed tomography (CT) continues to become more widely available for assessment of tumors in dogs, yet there are no studies describing the CT appearance of canine liposarcomas. In this retrospective, multicenter study, CT images of dogs with histologically confirmed liposarcomas were reviewed for size, location, attenuation, contrast enhancement, border definition, internal homogeneity, local infiltration, and mineralization. A total of 24 dogs with 26 liposarcomas were sampled. Mean attenuation was +15.2 (SD = 22.3) Hounsfield units (HU) with a range of –36 to +47.5 HU based on representative regions of interest. Twenty tumors (77%) contained focal areas of fat attenuation. All masses enhanced with contrast medium administration, which is distinct from what has been reported previously in infiltrative lipomas. Other CT features associated with canine liposarcomas included heterogeneous internal attenuation (81%) and lack of a clearly defined capsule (38%) suggesting infiltration of local structures. Six tumors (23%) had foci of mineralization. Findings from the current study indicated that liposarcoma should be considered as a differential diagnosis for mixed‐attenuation, contrast‐enhancing masses in dogs that contain at least one focus of fat attenuation on precontrast images; however, presence of foci of fat attenuation was not a necessary finding for the diagnosis of canine liposarcoma.     

Age-dependent patterns of bovine tuberculosis in cattle

Bovine tuberculosis (BTB) is an important livestock disease, seriously impacting cattle industries in both industrialised and pre-industrialised countries. Like TB in other mammals, infection is life long and, if undiagnosed, may progress to disease years after exposure. The risk of disease in humans is highly age-dependent, however in cattle, age-dependent risks have yet to be quantified, largely due to insufficient data and limited diagnostics. Here, we estimate age-specific reactor rates in Great Britain by combining herd-level testing data with spatial movement data from the Cattle Tracing System (CTS). Using a catalytic model, we find strong age dependencies in infection risk and that the probability of detecting infection increases with age. Between 2004 and 2009, infection incidence in cattle fluctuated around 1%. Age-specific incidence increased monotonically until 24–36 months, with cattle aged between 12 and 36 months experiencing the highest rates of infection. Beef and dairy cattle under 24 months experienced similar infection risks, however major differences occurred in older ages. The average reproductive number in cattle was greater than 1 for the years 2004–2009. These methods reveal a consistent pattern of BTB rates with age, across different population structures and testing patterns. The results provide practical insights into BTB epidemiology and control, suggesting that targeting a mass control programme at cattle between 12 and 36 months could be beneficial.     

A survey of owners' perceptions of fear of fireworks in a sample of dogs and cats in New Zealand

Abstract

AIMS: To establish reliable information regarding the behavioural responses of dogs and cats to fireworks in New Zealand; record interventions used by owners, and their perceived efficacies; and establish the prevalence of firework-related injury, and quantify owners' attitudes towards fireworks.

METHODS: A questionnaire targeting dog and cat owners was distributed via the Auckland Society for the Prevention of Cruelty to Animals (SPCA) Animals Voice magazine and 25 veterinary clinics. The questionnaire covered demographics of animals, fear of fireworks, severity of the fear, and behaviours exhibited. Also included were treatments tried, source and perceived efficacy, prevalence of injury, and owners' attitudes towards the sale of fireworks for private use.

RESULTS: From a total of 8,966 questionnaires distributed, 1,007 valid questionnaires were returned, representing 3,527 animals. Of these 1,635 (46%) animals displayed a level of fear of fireworks recognisable to their owners. Owners of dogs identified a significantly higher fear response than owners of cats but the duration of these fear responses did not differ between species. Fear of fireworks frequently resulted in dogs exhibiting active fear behaviours, whereas cats were more likely to exhibit hiding and cowering behaviours. A significantly increased severity and duration of fear response over time in dogs and cats was associated with owners who comforted them when they displayed a fearful response. Only 141/890 (15.8%) of owners sought professional treatment from a veterinarian, animal behaviourist or animal trainer for their animals, with variable efficacy. Six percent (51/923) of animals had received physical injuries from fireworks. The majority (837/1,007; 83%) of respondents, regardless of whether they owned a fearful animal or not, supported a ban on the sale of fireworks for private use.

CONCLUSIONS: The results provide valuable information that is, as yet, unsubstantiated in New Zealand, although potential biases exist due to the non-random selection of respondents. Differences between dogs and cats were likely due to differing responses to fear-provoking stimuli between the species. Owner-reported increase in fearful response over time for comforted animals may indicate a negative impact on the longer-term psychological welfare of their animal.

CLINICAL RELEVANCE: The greater the awareness of effective treatment plans for animals that suffer from a fear of fireworks, the greater the possibility that this fear can be reduced. Wider dissemination of effective owner behaviour and treatment programmes for firework fears is needed to improve levels of professional treatment for dogs and cats.     

Seroconversion to avian influenza virus in free-range chickens in the Riverland region of Victoria

Background Since 2005, H5N1 avian influenza (AI) has spread from South-East Asia to over 60 different countries, resulting in the direct death or slaughter of over 250,000,000 poultry. Migratory waterfowl have been implicated in this spread and in Australia there have been numerous isolations of low-pathogenicity AI virus from wild waterfowl and shorebirds. The Department of Human Services, Victoria maintains 10 sentinel free-range chicken flocks in the Riverland at locations that are populated by large numbers of waterfowl known to carry a range of strains of AI. Objective This study analysed historical samples collected in 1991–94 and 2003–06 from the library of serum samples for antibodies against AI to assess the potential for transfer of AI virus from wild waterfowl to free-range poultry. Results Of the 2000 serum samples analysed, 17 were positive for antibodies against AI and 87 were suspect, with a clustering of positive and suspect results in the years 1994, 2003 and 2004. There was also a clustering of positive samples at the site of the Barmah flock. Nine sequential sets of sera from individual chickens with at least one positive result were identified. Analysis of these sequential sets showed that infection was acquired on site but that the antibody response to AI infection was short-lived and was no longer detectable at 8 weeks after the positive finding. Conclusion The surveillance of sentinel chickens is a potential avenue for monitoring the circulation of AI viruses and could provide an early warning system for the commercial poultry industries.     

COMPUTED TOMOGRAPHIC FINDINGS OF FUNGAL RHINITIS AND SINUSITIS IN CATS

The computed tomographic (CT) findings of fungal rhinitis/sinusitis in cats were characterized. The CT images of 10 cats ranging in age from 7 to 13 years were examined. The mean age was 10.8 years and all were neutered males. Nasal aspergillosis was diagnosed in five cats, cryptococcosis in three cats, hyalohyphomycosis in one cat, and trichosporonosis in one cat. Bilateral disease was present in eight cats, seven had abnormal soft tissue attenuation in two-thirds of the nasal cavity, and six had turbinate lysis. Seven cats had also lysis of the hard palate, nasal septum, or frontal bone. One cat had lysis of the cribriform plate. Five of the nine cats whose lymph nodes were imaged had lymph node enlargement. There was contrast medium enhancement in the nasal cavity in all cats, with either a primarily peripheral rim or heterogeneous pattern. There appears to be an overlap of clinical signs, age, and CT features of cats with nasal neoplasia and those with fungal rhinitis/sinusitis.     

Over representation of Burmese cats with diabetes mellitus

Objective To determine if Burmese cats in Queensland have an increased risk of diabetes mellitus.
Design A retrospective study of diabetic and nondiabetic cats that had blood submitted to a veterinary clinical laboratory over a 22 month study period.
Sample population 4402 cats
Procedure Cats were considered diabetic if blood glucose concentration was > 11 mmol/L and fructosamine was > 406 μmol/L or hydroxybutyrate was >1 mmol/L. Cats were grouped into Burmese and non-Burmese. Adjusted odds ratios of diabetes were calculated for breed, gender and age group amongst cats with blood glucose > 11 mmol/L.
Results Burmese cats comprised 20% of 45 diabetic cats of known breed, which was higher (P < 0.001) than among the normoglycemic reference population of 2203 cats (7% Burmese). There were more females among the diabetic Burmese (62%), but this did not differ (P > 0.05) from the Burmese reference population (45% females). In contrast, males seemed to predominate among diabetic non-Burmese (63%), although this also did not differ (P > 0.05) from the reference population (55%) or from diabetic Burmese (38% males). The majority (90%) of diabetic cats were older than 6 years, irrespective of breed (median age 12 years, interquartile range 10 to 13 years). This was higher (χ²= 8.13, P < 0.005) than among the normoglycaemic reference population, where 69% were older than 6 years.
Conclusions Burmese cats were significantly over represented among cats with diabetes mellitus. Irrespective of breed, the risk of diabetes in the study population increased with age.