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J Segalés

Publications and source records attributed to J Segalés.

At least 19 recordsLinked to original sources
PubMed2006

Porcine circovirus type 2 antibody detection in backyard pigs from Mexico City.

PCV2 antibodies have been found in pigs from all continents. However, this finding has been mainly studied in domestic swine reared under intensive production conditions. Mexico City, with a human population over 19 million in 2005, has both urban and rural areas. The pig production in its rural area is based on small family backyard farms. Taking into account this rather unique form of rearing pigs, the objective of this study was to determine the seroprevalence in backyard pigs from the rural area of Mexico City. A total of 695 backyard pig serum samples from 108 small family farms belonging to seven municipal areas were studied by immunoperoxidase monolayer assay technique. One hundred six out of the 108 family farms (98.14%) had at least one positive serum sample. On the other hand, 136 (19.57%), 264 (37.99%) and 248 (34.82%) pigs had low, intermediate and high titres to PCV2, respectively. Only 53 samples (7.63%) were negative for PCV2 antibodies. No apparent differences in antibody titre groups were observed among backyard pigs from the different municipal areas. In conclusion, the present study, the first one performed in this kind of extensively produced pigs, indicates that PCV2 is ubiquitous in backyard pigs from Mexico City.

Animals↗
PubMed2006

Sow porcine circovirus type 2 (PCV2) status effect on litter mortality in postweaning multisystemic wasting syndrome (PMWS).

Previous studies have described a "litter effect" associated with mortality in postweaning multisystemic wasting syndrome (PMWS) affected farms. The main objective of this study was to evaluate litter mortality in different PMWS affected farms and to characterize it in relation to three variables of the sow: parity, porcine circovirus type 2 (PCV2) infectious status and PCV2 antibody titres. The study was performed in seven farms that experienced PMWS in nurseries and/or fattening areas. Fifteen sows from each farm were randomly selected from the same farrowing batch. Serum samples were analyzed for antibodies to PCV2 and for genomic detection of PCV2. Four piglets from each sow (60 piglets per farm) were selected and ear-tagged at birth. Out of 420 initial piglets, 104 (25%) died. Sixty three of them (60%) were necropsied, and 40 (63%) diagnosed as PMWS based on case definition criteria. Our results show that sow PCV2 viremia was significantly related to piglet mortality since more piglets per litter died from viremic than from non-viremic sows. Additionally, a significantly greater proportion of animals died from sows that had low antibody titres against PCV2 (39% vs. 18% from sows with medium to high antibody titres). The present study, of exploratory nature, confirms previous results and further characterizes the so called "litter effect" by establishing that the sow PCV2 status had a significant effect on litter mortality in PMWS affected farms.

Animals↗
PubMed2006

Molecular evolution of porcine circovirus type 2 genomes: phylogeny and clonality.

Porcine circoviruses (PCVs) type 1 (PCV1) and type 2 (PCV2) show high levels of nucleotide similarity, but PCV1 is considered non-pathogenic and PCV2 has been associated with several disease outcomes in pigs, mainly postweaning multisystemic wasting syndrome (PMWS). After exploring different topologies of the origin of PCVs, it was concluded that PCV1 and PCV2 seem to have a common origin. On the other hand, PCV2 could be divided into two groups (1 and 2) and eight clusters (1A to 1C and 2A to 2E), but none of those was apparently associated with disease status or geographic area. When phylogenetic trees constructed with the whole PCV2 genome, the cap or the rep genes were compared, some incongruence was identified. The possible existence of recombination was evaluated and cluster 1B was found to have a possible recombinant origin. Selective pressure was detected in all parts of the PCV2 genome, especially in the rep gene. Finally, the cap gene was the more suitable phylogenetic and epidemiological marker for PCV2, despite the fact that the virus can undergo recombination mainly within the first part of the rep region.

Animals↗
PubMed2006

Changes in peripheral blood leukocyte populations in pigs with naturally occurring exudative epidermitis.

The objective of the study was to analyze changes in peripheral blood leukocyte subsets in cases of naturally occurring exudative epidermitis (EE) in pigs. Five of ten piglets developed the chronic clinical form of EE 2-5 days after weaning (PW). Blood samples were obtained at 7, 14 and 21 days from both normal and clinically affected piglets for routine haematology and for the determination of CD45, CD21, CD4, CD8 and gammadeltaTCR cell markers by flow cytometry. When compared with clinically normal piglets EE affected pigs showed significantly decreased values of monocytes at 14 and 21 days PW, and increased numbers of neutrophils and leukocytes at 21 days PW. The EE affected pigs also had an early significant CD4(+) and CD8(high+) T lymphocyte proliferative response at 7 days PW. However affected pigs had a significantly reduced number of B (CD21(+)) and gammadeltaTCR(+) T lymphocytes in blood at 21 days PW. Although all values remained within the normal range, the significant differences in some peripheral blood leukocyte subsets between the two groups of piglets suggest that the generalised cutaneous infection with Staphylococcus hyicus is severe enough to induce a systemic inflammatory and immune responses.

Animals↗
PubMed2006

Clinical, pathological and toxicological findings of a iatrogenic selenium toxicosis case in feeder pigs.

Histopathological and toxicological analyses confirmed a clinical diagnosis of selenium (Se) intoxication in pigs from a farm in Spain. After an initial episode of diarrhoea, animals presented both dermatological and neurological signs; the most obvious sign was a marked hind limb paresis. Cutaneous lesions consisted on diffuse alopecia, multifocal skin necrosis and coronary band necrosis of the hooves. Central nervous system lesions involved the cervical and lumbar intumescences of the spinal cord and consisted of a severe, bilateral symmetrical poliomyelomalacia of the ventral horns; pons and medulla oblongata also presented lesions of polioencephalomalacia. Analyses of feed and sera from clinically affected pigs revealed a marked increase in Se concentration. Clinical investigations indicated that a failure in Se dosage in feed was the cause of the toxicosis.

Alopecia↗
PubMed2006

Effects of spray-dried porcine plasma and plant extracts on intestinal morphology and on leukocyte cell subsets of weaned pigs.

We evaluated the effects of a 6% spray-dried porcine plasma (SDPP) and a plant extracts mixture (XT; 5% carvacrol, 3% cinnamaldehyde, and 2% capsicum oleoresin) on the productive performance, intestinal morphology, and leukocyte cell subsets of early-weaned pigs compared with a control group. Morphometry of the jejunum, ileum, and colon, and immune cell analysis of blood, ileocolic lymph node (LN), and ileal Peyer's patches were done in 24 weaned pigs (20 +/- 2 d) at 19 or 21 d postweaning. Although SDPP and XT treatments did not increase ADG or ADFI, SDPP improved the G:F ratio (P = 0.024) compared with the control group. Dietary SDPP reduced the percentages of blood monocytes (P = 0.006) and macrophages in ileal Peyer's patches and LN (P = 0.04), of B lymphocytes (P = 0.04) and gammadelta+ T cells in LN (P = 0.009), and of intraepithelial lymphocytes (P = 0.026) as well as the density of lamina propria cells in the colon (P < 0.01). Dietary XT reduced intraepithelial lymphocyte numbers in jejunum (P = 0.034) and the percentages of blood cytotoxic cells (P = 0.07) and B lymphocytes in LN (P = 0.03); however, XT increased blood monocytes (P = 0.038) and the density of lamina propria lymphocytes in the colon (P = 0.003). These results indicate that dietary SDPP and plant extracts can affect intestinal morphology and immune cell subsets of gut tissues and blood in weaned pigs. Furthermore, the effects of SDPP suggest lower activation of the immune system of the piglets.

Animal Feed↗
PubMed2005

Pathological and aetiological studies of multifocal interstitial nephritis in wasted pigs at slaughter.

Multifocal interstitial nephritis in pigs has been associated with several infectious agents. The objective of the present study was to investigate several different potential infectious agents associated with "white-spotted" kidneys in pigs suffering from wasting at slaughter (aged 6-8 months). Twenty-nine case kidneys (with a "white-spotted" gross appearance) classified into 3 macroscopic lesional grades, and 15 control kidneys (lacking gross lesions), were obtained from a pig abattoir. Laboratory analyses to detect potential associations with the aforementioned pathological condition with Leptospira spp., porcine circovirus type 2 (PCV2), porcine parvovirus (PPV), porcine reproductive and respiratory syndrome virus (PRRSV), and bacteria, were carried out. Microscopically, interstitial nephritis with a lymphofollicular inflammatory pattern (follicular nephritis) was observed in both case and control kidneys, with a higher frequency seen in the former ones. No leptospires were identified, although antibodies to the Pomona and Bratislava serovars were detected. Some pyogenic bacteria were also isolated from both case and control kidneys. PCV2 nucleic acid was only detected in 1 case kidney. PRRSV antigen was not found in any tested sample. Some pigs were tested positive for PPV by serology. Apparently, none of the studied agents were specifically associated as being the potential cause of the renal lesions in the studied wasted pigs. The fact that these chronic lesions may have been the consequence of a previous infection with one of these studied microorganisms, or more, and eventually with other non-tested infectious agents during the growing-finishing period, cannot be ruled out.

Abattoirs↗
PubMed2005

Quantification of porcine circovirus type 2 (PCV2) DNA in serum and tonsillar, nasal, tracheo-bronchial, urinary and faecal swabs of pigs with and without postweaning multisystemic wasting syndrome (PMWS).

The present study focused on PCV2 quantification by TaqMan PCR in nasal (n=99), tonsillar (n=108), tracheo-bronchial (n=72), urinary (n=91) and faecal (n=42) swabs, as well as in serum (n=57), from a total of 146 pigs received at the Pathological Diagnostic Service at the Veterinary School of Barcelona (Spain). Animals were classified into three categories based on histopathological and in situ hybridisation (ISH) results: PMWS affected pigs (Group A, n=42), PCV2 subclinically infected pigs (Group B, n=29), and non-PMWS with PCV2 ISH negative pigs (Group C, n=75). Overall, tracheo-bronchial swabs had the higher PCV2 load followed by serum, tonsillar, nasal, faecal and, finally, urinary swabs. PCV2 genome was also detected in different proportions in all three categories of pigs; in all tested sites, viral load means were significantly higher (P 0.05) were observed among tested specimens when age-groups (pigs younger than 1.5 months, and equal or older than 1.5 months of age) were compared. In summary, PCV2 is presumably excreted through respiratory (nasal and tracheo-bronchial) and oral (tonsillar) secretions, urine and faeces of both PMWS and non-PMWS affected pigs, with higher viral loads being associated with the presence of PMWS lesions.

Age Factors↗
PubMed2005

An exploratory study on risk factors for postweaning multisystemic wasting syndrome (PMWS) in Spain.

An exploratory case-control study was carried out in Spain in 2002/2003, involving 62 pig farms of different production systems to assess risk factors that, in association with PCV2 infection, induce postweaning multisystemic wasting syndrome (PMWS) expression. To achieve this objective two groups of farms selected according to their PMWS status were compared: "cases" (farms with clinical PMWS, n = 32) and "controls" (farms without clinical PMWS, n = 30). A filled-in questionnaire and 45 blood samples (15 sows, and two groups of 15 pigs of 12 and 20 weeks of age, respectively) were obtained from each farm. Additionally, two to three diseased pigs were necropsied and relevant tissues to diagnose PMWS collected when PMWS was clinically suspected ("case" farms). A statistical analysis to compare "case" versus "control" farms was performed with the variables obtained from the questionnaire (191 variables) and the serologic test results (20 variables). Data were analysed using conditional logistic regression with a nested n:m matched design taking into account the farm size. Three variables were found significant in the final model: two related to vaccination scheme and one to PCV2 seroprevalence in growing pigs. Vaccination of gilts against PRRSV increased the odds of PMWS expression and vaccination of sows against atrophic rhinitis was related to decreased odds of the disease; however, the possibility that those two factors could be spurious effects (due to the small sample size) or confounding variables cannot be ruled out. On the other hand, a higher prevalence of antibodies to PCV2 at 12 weeks of age was observed in pigs from "case" farms than in pigs from "control" farms. This result suggests that an earlier infection with PCV2 might be a risk factor for PMWS expression.

Animals↗
PubMed2005

Identification of viral pathogens in aborted fetuses and stillborn piglets from cases of swine reproductive failure in Spain.

The objective of the present study was to determine the presence of recognised abortifacient viruses such as porcine reproductive and respiratory virus (PRRSV), Aujeszky's disease virus (ADV), porcine parvovirus (PPV) and porcine circovirus type 2 (PCV2), in tissues from aborted fetuses and stillborn neonates in cases of late reproductive failure in swine. A total of 293 specimens (fetuses aborted in the last third of gestation and stillborn piglets) from 100 different cases of late-term abortions and premature farrowing from 15 different Spanish provinces were studied. PRRSV was detected in 9/100 cases by RT-PCR. Only 1/100 cases analysed (corresponding to a late-term aborted fetus with a negative PRRSV RT-PCR result) was positive for PCV2 by PCR. Neither ADV (monitored by viral isolation plus antigen detection) nor PPV (monitored by ELISA antigen capture test) infection was identified. The results suggest that PRRSV is one of the most important infectious agents, if not the most relevant one, associated with fetal infection leading to abortion or premature farrowing in Spain. Moreover, other viral pathogens such as ADV, PPV and PCV2 seem to have a minor impact on reproductive disease.

Abortion, Veterinary↗
PubMed2005

Histological basis of the porcine femoral artery for vascular research.

The similarities between the porcine and human cardiovascular systems make the pig a useful animal model for the study of vascular biology. However, a standardized method is needed to describe the normal histological properties of porcine arteries in order to evaluate pathologic lesions in future studies. Descriptive and morphometric analyses were done on 16 porcine femoral arteries. For these purposes, three histological stains (haematoxylin eosin, Masson's trichrome, and orcein), four immunohistochemical methods (using antibodies anti-alpha-actin, anti-CD3, anti-L1 and anti-lysozyme), and a glycohistochemical method (using Dolichos biflorus lectin) were performed. The porcine femoral arteries evaluated had a mean total area of 6.25 +/- 1.99 mm(2) and a diameter of 2.79 +/- 0.41 mm. The majority of the total area was occupied by the medial layer (42.97 +/- 5.38%) and was mainly constituted by smooth muscle cells (94.58 +/- 2.65%). All the cell markers used reacted with porcine paraffin-embedded tissue. However, the anti-lysozyme antibody was excluded from this histological analysis because of cytoplasmatic reactivity in smooth muscle cells. In summary, this study proposes histological methods to describe the normal characteristics of the porcine femoral artery and raises the possibility of applying this methodology in future studies on porcine vascular research.

Animals↗
PubMed2005

Systemic AA-amyloidosis in a European wild boar (Sus scrofa) suffering from generalized tuberculosis.

Summary An adult female wild boar (Sus scrofa) was found moribund in Cabaneros National Park (central Spain). The animal had a markedly emaciated carcass, with body weight of 25.9 kg. At necropsy, most of the parenchymatous organs had widespread variably sized granulomas. Generalized tuberculosis was confirmed by PCR detection of Mycobacterium bovis in the mandibular lymph node. Large amounts of a hyaline, pale eosinophilic material were observed in liver, kidney and intestine. Congo red staining and green birefringence identified amyloid, which was further classified as AA type based on immunohistochemical results. It is speculated that the abundant serum amyloid A derivatives deposited in the tissues as AA-amyloid may be associated with the generalized tuberculosis. This is the first report of amyloidosis in the European wild boar.

Amyloidosis↗
PubMed2005

Myocarditis and generalised vasculitis associated with leishmaniosis in a dog.

A three-year-old, female bulldog was presented with bilateral uveitis, apathy, listlessness, generalised lymphadenopathy and perivulvar haematoma. The initial laboratory studies showed non-regenerative anaemia, polyclonal gammopathy and a high urine protein:creatinine ratio. Serology for leishmaniosis was positive and treatment with allopurinol and meglumine antimoniate was started. Despite treatment, the dog's clinical condition deteriorated. Signs included cutaneous ecchymosis, respiratory distress and finally cardiorespiratory arrest. Histopathological studies of postmortem tissue samples revealed a generalised vasculitis of several internal organs and severe myocarditis. Leishmania species organisms were identified in affected tissues using immunoperoxidase labelling and PCR techniques.

Animals↗
PubMed2005

Postweaning multisystemic wasting syndrome (PMWS) in pigs in Croatia: detection and characterisation of porcine circovirus type 2 (PCV2).

The objective of this study was to characterise porcine circovirus type 2 (PCV2) from pigs with naturally occurring postweaning multisystemic wasting syndrome (PMWS) in Croatia, and to determine the epizootiological, clinical and pathomorphological features of the disease. During a systematic health monitoring programme conducted in the period from January 2002 to June 2003, PMWS was suspected on eight different pig-producing farms in Croatia. The diagnosis of PMWS met all three key criteria: the presence of compatible clinical signs, the presence of the characteristic microscopic lymphoid lesions, and the detection of PCV2 within the lesions by polymerase chain reaction (PCR) and by in situ hybridisation (ISH). Moreover, PCV2 DNA from swine tissues was extracted and sequenced. The phylogenetic analysis of 4 Croatian PCV2 strains showed close relationship to PCV2 strains isolated in Slovenia, France, the Netherlands, the United Kingdom, China and Hungary. PCV2 was also demonstrated by electron microscopy in the lymph node of an affected animal. This is the first demonstration of PMWS in Croatia based on all scientifically accepted diagnostic criteria.

Animals↗