Descriptive summary of an outbreak of porcine post-weaning multisystemic wasting syndrome (PMWS) in New Zealand

CASE HISTORY: Investigations were conducted to determine the cause of an acute, multi-farm outbreak of porcine respiratory disease that included diarrhoea and subsequent loss of body condition in affected pigs. A definition for post-weaning multisystemic wasting syndrome (PMWS) including both clinical and pathological features, previously developed for the pig industry in New Zealand, was applied to the current outbreak. In addition to self-reporting by owners of affected farms, local veterinarians, disease and epidemiology consultants, and animal health officials from the Ministry of Agriculture and Forestry (MAF) were involved in conducting farm visits and submission of diagnostic specimens.

CLINICAL FINDINGS AND DIAGNOSIS: Pathogens known to be endemic in the pig industry in New Zealand as well as likely exotic diseases were excluded as causative agents of the outbreak. Clinical signs including dyspnoea, diarrhoea, and rapid loss of body condition were consistent with the New Zealand case definition for PMWS. Interstitial pneumonia, pulmonary oedema, generalised lymph-node enlargement, and presence of porcine circovirus type 2 (PCV2) inclusion bodies were consistently identified in affected pigs. Classical swine fever virus (CSFv), Porcine reproductive and respiratory syndrome virus (PRRSv), and Influenza virus were ruled out, using molecular and traditional virological techniques. Spread of the disease between farms was hypothesised to be facilitated by locally migrating flocks of black-backed seagulls. The original source of the disease incursion was not identified.

DIAGNOSIS: Based on the consistent presence of circovirusassociated lesions in lymphoid tissues in combination with generalised enlargement of lymph nodes, histiocytic interstitial pneumonia, clinical wasting, and poor response to antibiotic therapy, a diagnosis of PMWS was made.

CLINICAL RELEVANCE: PMWS should be considered in the differential diagnoses of sudden onset of respiratory dyspnoea, diarrhoea, and rapid loss of body condition in young pigs in New Zealand pig herds.     

Utilization of deoiled castor cake for crop production

A screen house experiment was undertaken to study effect of time of application of deoiled castor cake on the yield, N and P uptake by wheat crop. The results indicate that the wheat growth decreased significantly with increasing dose of castor cake, when castor cake was applied just before sowing of wheat. When castor cake was applied 10 days before wheat sowing, the dry matter yield (DMY) of wheat increased up to 0.125% dose of castor cake and reduced thereafter. But when the castor cake was applied 20 days before wheat sowing, the DMY was at par under all the doses of castor cake and better than control indicating the degradation of the toxicants produced by the castor cake. Application of castor cake can also be helpful in reducing the cost of phosphatic fertilizer. Thus it can be concluded that castor cake should be applied at least 3 weeks before sowing of the crop and keeping the field moist for degradation of the toxicants.     

Correlation of salt gland function with levels of chlorpyrifos in the feed of mallard ducklings

The salt gland of the mallard duckling, Anas platyrhynchos, has been proposed as a model for testing the toxicity of organophosphorous pesticides because these compounds depress the function of the gland. Ducklings on either a fresh- or saltwater diet were fed various levels of chlorpyrifos in their feed to see if there was a correlation between level of pesticide, salt gland function, and brain and salt gland cholinesterase activity. The results showed that there was an inverse correlation between level of chlorpyrifos and (i) salt gland function, (ii0 brain cholinesterase activity, and (iii) salt gland cholinesterase activity. These results support the premise that the salt gland of the mallard duckling may be a useful model for testing exposure to organophosphorous pesticides.     

基于RS和GIS的柘皋河流域景观空间格局研究

在RS和GIS技术的支持下,运用景观生态学原理,以2000年LandsatTM 7遥感数据为数据源,通过影像解译和实地调查获得柘皋河流域景观类型图,并采用景观指数分析法对流域内景观空间格局做定量分析,为流域内生态保护和区域经济的可持续发展提供有益参考。结果显示：柘皋河流域是以农业为主的发展模式。景观异质性高,分布相对均匀;耕地破碎化程度低,连通性好,利于农业发展;居民点与交通用地破碎化程度高,边缘效应强,对周围影响大。A区农业化和非农化矛盾最强烈。B区景观异质性高,景观类型分布均匀,生态结构稳定。C区景观异质性低,生态稳定性较差。     

The benefits of fringing mangrove systems to Mumbai

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Serum and skin IgA concentrations in normal and atopic dogs

Objective To compare serum and skin surface IgA concentrations from atopic and normal dogs.
Procedure IgA concentrations in sera and skin washings of 20 clinically normal dogs that had no history of pruritus or skin disease were compared to those obtained in 20 dogs with a diagnosis of atopy determined by history, clinical examination and positive intradermal skin test.
Results There was no significant difference in the mean serum IgA concentration in normal dogs (252 ± 187 mg/L) versus atopic animals (314 ± 327). When skin washings from all sites in both groups were compared, atopic dogs had significantly greater concentrations of IgA in their skin washings than normal dogs as evaluated by an enzyme-linked immunoassay (P < 0.001). However, there was no significant difference between the individual sites of the skin washings of atopic and normal dogs.
Conclusion IgA concentrations of skin washings in atopic dogs were greater than in normal dogs. Further investigations need to determine if the greater concentrations were caused by nonspecific inflammation or by secretion of allergen-specific IgA onto the skin surface.     

The efficacy of diazinon impregnated ear tags against buffalo fly and resulting weight gains and diazinon residues in meat and milk

Ear tags impregnated with 20% diazinon were evaluated for their efficacy against the buffalo fly (Haematobia irritans exigua) on beef cattle in southern Queensland. Buffalo fly numbers and weight changes were recorded and diazinon residues in tissues of beef cattle and milk from lactating dairy cattle were assayed at different time intervals after tagging. In 2 efficacy trials conducted over 19 and 20 weeks, the mean numbers of buffalo fly on cattle each fitted with ear tags were 1 to 9 and 0 to 16, respectively, in trials 1 and 2, compared with 44 to 345 and 26 to 306 per head on untreated herds, respectively, despite regular spraying of the untreated herd in trial 1 with cyper-methrin to reduce fly burdens. Percentage buffalo fly control was 96.7 to 99.5% and 89.3 to 100% in the 2 trials. Cattle fitted with ear tags gained an average of 94 kg body weight after 5 months compared with 61 kg in the untreated herd, a net increase of 60% in treated animals compared with 28% in the untreated herd. Mean diazinon residue concentrations in the fat of perianal tissue biopsies were 0.02 to 0.03 mg/kg 1 to 8 weeks after tagging. Mean diazinon residue concentrations in the butterfat of milk from lactating dairy cattle were 0.01 to 0.04 mg/kg after tagging.