Biosecurity assessment of Argentinian pig farms

The pig industry is growing very fast in Argentina with an increasing need for replacement animals, feedstuff and transportation of animals. One of the main competitive advantages of the Argentinian pig industry is its being free of most major pig diseases. Within this context, applying measures aimed to reduce the risk of introduction and spread of pathogens is critical. The aim of the present study was to assess the biosecurity of Argentinian pig farms. Two types of farms were assessed: firstly, all official suppliers of high-genetic-value (n = 110) and secondly, a sample from commercial farms (n = 192). Data on the external and internal biosecurity practices applied on the farms was collected with a questionnaire. Data was analysed using a correspondence analysis and a hierarchical clustering analysis, which allowed identification of types of farms with regard to the biosecurity measures applied. Key variables characterizing the clusters were identified through an indicator value analysis. In addition, the external biosecurity of the farms was evaluated by using risk assessment tools with respect to the potential introduction of porcine epidemic diarrhoea virus. Results made evident three clusters: the first one which, amongst other measures, applied several barriers to prevent the entry of people, trucks and other vehicles, and could be considered as a group of high biosecurity, and the two other groups which applied a lower number of external and internal biosecurity measures. The results of the risk assessment showed that the routes with the highest risk of disease introduction were: replacement animals, vehicles transporting feed or animals, and visitors. The assessment of the external biosecurity showed that most Argentinian farms were not prepared for the contingency of a pathogen such as porcine epidemic diarrhoea virus. Special efforts should be made in official suppliers of high-genetic-value farms with poor biosecurity scores since they are at the top of the pig production chain and can be key for the spread of diseases.info:eu-repo/semantics/acceptedVersio

Directed microbial biosynthesis of deuterated biosurfactants and potential future application to other bioactive molecules

Deuterated rhamnolipids were produced using strain AD7 of Pseudomonas aeruginosa, which was progressively adapted to increasing levels of deuterium in D2O and carbon substrates. Fourteen different deuterated rhamnolipid structures, including structural isomers, were produced which is similar to normal protonated structures. There were two main products monorhamnolipid Rha-C-10-C-10 and dirhamnolipid Rha(2)-C-10-C-10. The levels of deuteration varied from 16% with 25% D2O + h-glycerol to 90% with 100% D2O + d-glycerol. When d-tetradecane was used with H2O, virtually all the deuterium appeared in the lipid chains while using h-tetradecane + D2O led to the majority of deuterium in the sugars. The adaptation to growth in deuterium appeared to be metabolic since no genetic changes could be found in the key rhamnolipid biosynthetic genes, the rhamnosyl transferases RhlB and RhlC. Deuterated sophorolipids were similarly produced using Candida bombicola and Candida apicola although in this case, no adaptation process was necessary. Up to 40 different sophorolipids were produced by these yeasts. However, unlike the rhamnolipids, use of D2O did not lead to any deuteration of the lipid chains, but direct incorporation into the lipid was achieved using d-isostearic acid. The results from these experiments show the feasibility of producing deuterated bioactive compounds from microorganisms coupled with the possibility of manipulating the pattern of labelling through judicious use of different deuterated substrates

Lupus nephritis in Chinese children--a territory-wide cohort study in Hong Kong

We report a multicenter study of Chinese children in Hong Kong with systemic lupus erythematosus (SLE) nephritis. Children were included if: they fulfilled the ACR criteria, had significant proteinuria or casturia, were Chinese and younger than 19 years and had been diagnosed with SLE between January 1990 and December 2003. Investigators in each center retrieved data on clinical features, biopsy reports, treatment and outcome of these patients. There were 128 patients (eight boys, 120 girls; mean age: 11.9+/-2.8 years). About 50% presented with multisystem illness and 40% with nephritic/nephrotic symptoms. Negative anti-dsDNA antibodies were found in 6% of the patients. Renal biopsy revealed WHO Class II, III, IV and V nephritis in 13 (10%), 22 (17%), 69 (54%) and 13 (10%) patients, respectively. The clinical severity of the nephritis did not accurately predict renal biopsy findings. The follow-up period ranged from 1 to 16.5 years (mean+/-SD: 5.76+/-3.61 years). During the study five patients died (two from lupus flare, one from cardiomyopathy, two from infections). Four patients had endstage renal failure (ESRF) (one died during a lupus flare). All deaths and end-stage renal failure occurred in the Class IV nephritis group. Chronic organ damage was infrequent in the survivors. The actuarial patient survival rates at 5, 10 and 15 years of age were 95.3, 91.8, and 91.8%, respectively. For Class IV nephritis patients, the survival rates without ESRF at 5, 10, and 15 years were 91.5, 82.3 and 76%, respectively. The survival and chronic morbidity rates of the Chinese SLE children in the present study are comparable to those of other published studies.postprin

Swine hemoplasmosis detected in farms of Argentina by a new nested PCR assay

Swine hemoplasmosis or swine infectious anemia is a worldwide distribution disease caused by the hemotropic mycoplasmas Mycoplasma suis and Mycoplasma parvum. The aim of this study was to determine the presence of M. suis-M. parvum infection in subclinical pigs from herds of Buenos Aires province, Argentina, by means of new nested PCR. The PCR assay primers were designed based on the 16S ribosomal gene sequences of swine hemoplasmas available at GenBank. To standardize the assay, pig blood samples positive for hemoplasma by May Grünwald-Giemsa (MGG) stained blood smears were used. A total of 482 pig blood samples were analyzed. A 32% (154/482) of MGG stained blood smears were positive to M. suis o M. parvum. From these 154 samples, 47% (72/154) were positive by PCR. Sequences of PCR products amplified with these primers always showed identity with M. suisor M. parvum, validating their specificity and highlighting the unspecific amplification with hemoplasmas of other species. This is the first assay designed in Argentina to identify M. suis and M. parvum. However, considering the advances in the knowledge of the genome of hemoplasmas worldwide, further studies should be performed to standardize new assays for the diagnosis of swine hemoplasmosis in Argentina

Outbreak of Hemagglutinating encephalomyelitis coronavirus infection in pigs in Argentina. Pathological, virological, molecular and serological study

Se describe un brote en lechones lactantes caracterizado por vómitos, signos nerviosos, emaciación y alta mortalidad producida por el coronavirus de la encefalomielitis hemaglutinante del cerdo (PHE-CoV). Se realizó la confirmación diagnóstica por medio de estudios histopatológicos, inmunohistoquímicos (IHQ) y de biología molecular (RT-PCR y secuenciación de los amplicones). Los hallazgos más salientes fueron: encefalitis o meningoencefalomielitis no supurativa y ganglioneuritis, presencia de manguitos perivasculares con degeneración neuronal de los plexos de Meissner y Auerbach en la región pilórica del estómago. Mediante IHQ se observó inmunomarcación en el citoplasma de las neuronas del tallo cerebral y del ganglio trigémino. Mediante RT-PCR de muestras de tejido nervioso IHQ positivas se visualizó un producto de igual pb que el primer de pancoronavirus utilizado. La secuenciación del amplicón se correspondió en un 95% con las secuencias reportadas de la cepa VW572 de PHE-CoV (GenBank). Se realizó un estudio epidemiológico preliminar mediante la prueba serológica de inmunofluorescencia indirecta (IFI), en 9 granjas. Sobre el total de las granjas estudiadas 6 fueron positivas; siendo la granja motivo del trabajo, la única que manifestó entidad clínica. Estos resultados preliminares indican la presencia de una infección endémica por PHE-CoV en la República Argentina, en la mayoría de los casos en forma subclínica. Este trabajo constituye la primera comunicación de un brote de PHE-CoV en la Argentina y en Sudamérica, considerándosela como una enfermedad emergente.An outbreak of vomiting, wasting and nervous signs in piglets less than 3 weeks old caused by porcine hemagglutinating encephalomyelitis coronavirus (PHECoV) infection is described. The etiological diagnosis was made by histopathology, immunohistochemistry (IHC), RTPCR and genomic sequence (GS) studies. Nonsuppurative encephalomyelitis or meningoencephalomyelitis, ganglioneuritis and perivascular cuffing with neuronal degeneration on intramural plexus of stomach were the main changes. By IHC, PHE-CoV was detected in neurons of the brainstem and in the trigeminal ganglion which correlates with the RT-PCR products detected in the same samples. Sequence analysis of PCR amplicons showed 95% correspondence with the WW572 strain of PHE-CoV virus from GenBank reference. A preliminary epidemiological study was performed by indirect immunofluorescence antibody test (IFAT) in 9 farms. Results of serological survey to detect antibodies against PHE-CoV by IFAT showed 6 positive farms. However, only the farm under study reported clinical signs. These preliminary results showed that PHE-CoV infection is widespread in Argentina in subclinical form, however new outbreaks might occur particularly in naive farms. The above results confirmed PHE-CoV infection as newly recognized emerging disease of pigs in Argentina and South America.Facultad de Ciencias Veterinaria

Outbreak of Hemagglutinating encephalomyelitis coronavirus infection in pigs in Argentina. Pathological, virological, molecular and serological study

Se describe un brote en lechones lactantes caracterizado por vómitos, signos nerviosos, emaciación y alta mortalidad producida por el coronavirus de la encefalomielitis hemaglutinante del cerdo (PHE-CoV). Se realizó la confirmación diagnóstica por medio de estudios histopatológicos, inmunohistoquímicos (IHQ) y de biología molecular (RT-PCR y secuenciación de los amplicones). Los hallazgos más salientes fueron: encefalitis o meningoencefalomielitis no supurativa y ganglioneuritis, presencia de manguitos perivasculares con degeneración neuronal de los plexos de Meissner y Auerbach en la región pilórica del estómago. Mediante IHQ se observó inmunomarcación en el citoplasma de las neuronas del tallo cerebral y del ganglio trigémino. Mediante RT-PCR de muestras de tejido nervioso IHQ positivas se visualizó un producto de igual pb que el primer de pancoronavirus utilizado. La secuenciación del amplicón se correspondió en un 95% con las secuencias reportadas de la cepa VW572 de PHE-CoV (GenBank). Se realizó un estudio epidemiológico preliminar mediante la prueba serológica de inmunofluorescencia indirecta (IFI), en 9 granjas. Sobre el total de las granjas estudiadas 6 fueron positivas; siendo la granja motivo del trabajo, la única que manifestó entidad clínica. Estos resultados preliminares indican la presencia de una infección endémica por PHE-CoV en la República Argentina, en la mayoría de los casos en forma subclínica. Este trabajo constituye la primera comunicación de un brote de PHE-CoV en la Argentina y en Sudamérica, considerándosela como una enfermedad emergente.An outbreak of vomiting, wasting and nervous signs in piglets less than 3 weeks old caused by porcine hemagglutinating encephalomyelitis coronavirus (PHECoV) infection is described. The etiological diagnosis was made by histopathology, immunohistochemistry (IHC), RTPCR and genomic sequence (GS) studies. Nonsuppurative encephalomyelitis or meningoencephalomyelitis, ganglioneuritis and perivascular cuffing with neuronal degeneration on intramural plexus of stomach were the main changes. By IHC, PHE-CoV was detected in neurons of the brainstem and in the trigeminal ganglion which correlates with the RT-PCR products detected in the same samples. Sequence analysis of PCR amplicons showed 95% correspondence with the WW572 strain of PHE-CoV virus from GenBank reference. A preliminary epidemiological study was performed by indirect immunofluorescence antibody test (IFAT) in 9 farms. Results of serological survey to detect antibodies against PHE-CoV by IFAT showed 6 positive farms. However, only the farm under study reported clinical signs. These preliminary results showed that PHE-CoV infection is widespread in Argentina in subclinical form, however new outbreaks might occur particularly in naive farms. The above results confirmed PHE-CoV infection as newly recognized emerging disease of pigs in Argentina and South America.Facultad de Ciencias Veterinaria