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1.
Arch Virol ; 165(5): 1141-1150, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32222822

RESUMO

Pigs are capable of harbouring influenza A viruses of human and avian origin in their respiratory tracts and thus act as an important intermediary host to generate novel influenza viruses with pandemic potential by genetic reassortment between the two viruses. Here, we show that two distinct H1N2 swine influenza viruses contain avian-like or classical swine-like hemagglutinins with polymerase acidic (PA) and nucleoprotein (NP) genes from 2009 pandemic H1N1 influenza viruses that were found to be circulating in Korean pigs in 2018. Swine H1N2 influenza virus containing an avian-like hemagglutinin gene had enhanced pathogenicity, causing severe interstitial pneumonia in infected pigs and mice. The mortality rate of mice infected with swine H1N2 influenza virus containing an avian-like hemagglutinin gene was higher by 100% when compared to that of mice infected with swine H1N2 influenza virus harbouring classical swine-like hemagglutinin. Further, chemokines attracting inflammatory cells were strongly induced in lung tissues of pigs and mice infected by swine H1N2 influenza virus containing an avian-like hemagglutinin gene. In conclusion, it is necessary for the well-being of humans and pigs to closely monitor swine influenza viruses containing avian-like hemagglutinin with PA and NP genes from 2009 pandemic H1N1 influenza viruses.


Assuntos
Vírus da Influenza A Subtipo H1N2/crescimento & desenvolvimento , Infecções por Orthomyxoviridae/veterinária , Doenças dos Suínos/virologia , Fatores de Virulência/genética , Animais , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H1N2/genética , Vírus da Influenza A Subtipo H1N2/isolamento & purificação , Vírus da Influenza A Subtipo H1N2/patogenicidade , Camundongos , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/virologia , Proteínas de Ligação a RNA/genética , Análise de Sobrevida , Suínos , Doenças dos Suínos/patologia , Proteínas do Core Viral/genética , Virulência
2.
J Anim Sci ; 98(2)2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31943029

RESUMO

The enteric pathogen Lawsonia intracellularis is one of the main causes of diarrhea and compromised weight gain in pigs worldwide. Traditional cell-line cultures have been used to study L. intracellularis pathogenesis. However, these systems fail to reproduce the epithelial changes observed in the intestines of L. intracellularis-infected pigs, specifically, the changes in intestinal cell constitution and gene expression. A more physiologically accurate and state-of-the-art model is provided by swine enteroids derived from stem cell-containing crypts from healthy pigs. The objective of this study was to verify the feasibility of two-dimensional swine enteroids as in vitro models for L. intracellularis infection. We established both three- and two-dimensional swine enteroid cultures derived from intestinal crypts. The two-dimensional swine enteroids were infected by L. intracellularis in four independent experiments. Enteroid-infected samples were collected 3 and 7 d postinfection for analysis using real-time quantitative PCR and L. intracellularis immunohistochemistry. In this study, we show that L. intracellularis is capable of infecting and replicating intracellularly in two-dimensional swine enteroids derived from ileum.


Assuntos
Infecções por Desulfovibrionaceae/veterinária , Lawsonia (Bactéria) , Organoides/metabolismo , Doenças dos Suínos/microbiologia , Animais , Infecções por Desulfovibrionaceae/microbiologia , Infecções por Desulfovibrionaceae/patologia , Imuno-Histoquímica , Mucosa Intestinal/patologia , Intestinos/patologia , Suínos , Doenças dos Suínos/patologia
3.
Emerg Microbes Infect ; 9(1): 88-94, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31900060

RESUMO

Infection with a novel H10N8 influenza virus in humans was first described in China in December 2013, which raised concerns related to public health. This novel virus was subsequently confirmed to have originated from a live poultry market. However, whether this virus can infect other mammals remains unclear. In the present study, antibody specific for H10N8 influenza virus was detected in swine herds in southern China during serological monitoring for swine influenza virus. The pathogenicity and transmissibility of this H10N8 influenza virus to swine was examined. The results showed that swine are susceptible to infection with human-origin H10N8 influenza virus, which causes viral shedding, severe tissue lesions, and seroconversion, while infection with avian-origin H10N8 influenza virus causes only seroconversion and no viral shedding. Importantly, human-origin H10N8 influenza virus can inefficiently be transmitted between swine and cause seroconversion through direct contact. This study provides a new perspective regarding the ecology of H10N8 influenza virus and highlights the importance of epidemiological monitoring of the H10N8 influenza virus in different animal species, which will be helpful for preventing and controlling future infections by this virus.


Assuntos
Vírus da Influenza A Subtipo H10N8/fisiologia , Infecções por Orthomyxoviridae/veterinária , Doenças dos Suínos/imunologia , Doenças dos Suínos/transmissão , Animais , Anticorpos Antivirais/imunologia , China , Humanos , Vírus da Influenza A Subtipo H10N8/patogenicidade , Pulmão/patologia , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/transmissão , Sus scrofa , Suínos , Doenças dos Suínos/patologia , Doenças dos Suínos/virologia , Zoonoses
4.
Emerg Microbes Infect ; 9(1): 20-31, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31859605

RESUMO

Porcine deltacoronavirus (PDCoV) is an emerging swine coronavirus that causes severe diarrhea, resulting in high mortality in neonatal piglets. Despite widespread outbreaks in many countries, no effective PDCoV vaccines are currently available. Here, we generated, for the first time, a full-length infectious cDNA clone of PDCoV. We further manipulated the infectious clone by replacing the NS6 gene with a green fluorescent protein (GFP) to generate rPDCoV-ΔNS6-GFP; likewise, rPDCoV-ΔNS7 was constructed by removing the ATG start codons of the NS7 gene. Growth kinetics studies suggest that rPDCoV-ΔNS7 could replicate similarly to that of the wild-type PDCoV, whereas rPDCoV-ΔNS6-GFP exhibited a substantial reduction of viral titer in vitro and in vivo. Piglets inoculated with rPDCoV-ΔNS7 or wild-type PDCoV showed similar diarrheic scores and pathological injury. In contrast, rPDCoV-ΔNS6-GFP-infected piglets did not show any clinical signs, indicating that the NS6 protein is an important virulence factor of PDCoV and that the NS6-deficient mutant virus might be a promising live-attenuated vaccine candidate. Taken together, the reverse genetics platform described here not only provides more insights into the role of PDCoV accessory proteins in viral replication and pathogenesis, but also allows the development of novel vaccines against PDCoV infection.


Assuntos
Infecções por Coronavirus/veterinária , Coronavirus/fisiologia , Doenças dos Suínos/virologia , Proteínas Virais Reguladoras e Acessórias/genética , Vacinas Virais/genética , Animais , Animais Recém-Nascidos , Doenças Transmissíveis Emergentes/imunologia , Doenças Transmissíveis Emergentes/patologia , Doenças Transmissíveis Emergentes/veterinária , Doenças Transmissíveis Emergentes/virologia , Coronavirus/classificação , Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Citocinas/imunologia , DNA Complementar , Genoma Viral , Genética Reversa , Sus scrofa , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/patologia , Replicação Viral , Eliminação de Partículas Virais
5.
BMC Vet Res ; 15(1): 454, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31847840

RESUMO

BACKGROUND: Articular osteochondrosis follows a dynamic development pattern. Lesions arise, in incidence peaks compatible with failure of cartilage canal vessels during incorporation into bone, and can also resolve. Lesions that resolve before examination at a single time point will constitute false-negative diagnoses. The aim of the study was to identify physeal osteochondrosis lesions in pigs and monitor their development by computed tomography (CT), to determine if they follow a similar dynamic development pattern to articular osteochondrosis. RESULTS: Thirteen physes were evaluated bilaterally in up to eight biweekly CT scans from 18 male Landrace pigs age 70-180 days (total: 112 scans), generating 2912 scores. There were 1754 (60%) lesion-negative scores and 1158 (40%) lesion-positive scores. Positive scores comprised 138 lesions present at the start and 235 lesions that developed during the study, from 4 to 32 lesions per physis (median: 15 lesions). There were 1-2 peaks in the incidence curves for 12/13 examined physes, the exception being the proximal humerus. Positive scores also included 785 times that lesions persisted, from 1.3-4.8 examination intervals per lesion (median: 2.8 intervals). Negative scores included 190 times that lesions resolved, from 19 to 100% of lesions per physis (median: 65%). Lesions resolved by filling with bone from marginal sclerosis and reparative ossification centres. In the distal scapula and distal fibula, perichondrial new bone formation occurred that led to permanent enlargement of physeal regions. Angular limb deformity was not identified in any pig. CONCLUSIONS: Physeal osteochondrosis followed a similar dynamic development pattern to articular osteochondrosis. There were peaks in the incidence curves, compatible with failure of vessels during incorporation into bone. In some physes, osteochondrosis led to permanent enlargement, potentially relevant for decubital ulcers. The relationship between physeal osteochondrosis and angular limb deformity must be examined further in pigs over 6 months old in future.


Assuntos
Osteocondrose/veterinária , Doenças dos Suínos/diagnóstico por imagem , Tomografia Computadorizada por Raios X/veterinária , Animais , Progressão da Doença , Epífises/diagnóstico por imagem , Masculino , Osteocondrose/diagnóstico por imagem , Osteocondrose/patologia , Sus scrofa , Suínos , Doenças dos Suínos/patologia
6.
Can J Vet Res ; 83(4): 242-247, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31571722

RESUMO

The objective of this study was to investigate whether a virulent Canadian isolate of Senecavirus A (SVA) causes idiopathic vesicular disease (IVD) in pigs. Senecavirus A, which was first isolated in the United States in 2002 as Seneca Valley Virus, was linked to cases of porcine idiopathic vesicular disease in Canada in 2007 and in the United States in 2010. Since 2014, SVA outbreaks in Brazil, the US, Canada, China, Thailand, and Colombia point to an expanding global distribution and the need to study the pathogenicity of the virus. Unlike the prototype virus, recent US isolates of SVA have been shown to cause vesicular disease in pigs. We report vesicular disease in pigs following experimental inoculation with a 2016 Canadian isolate of SVA. All inoculated pigs developed vesicular lesions regardless of route of inoculation. Virus was detected in blood and oral fluids as well as on oral and fecal swabs. In addition, all pigs seroconverted to SVA by 6 days post-inoculation (DPI). This study confirms that recent Canadian isolates of SVA cause vesicular disease in pigs and highlights the importance of monitoring SVA for increased virulence.


Assuntos
Infecções por Picornaviridae/veterinária , Picornaviridae/patogenicidade , Doenças dos Suínos/virologia , Animais , Anticorpos Antivirais/sangue , Canadá/epidemiologia , Ensaio de Imunoadsorção Enzimática , Testes de Neutralização , Infecções por Picornaviridae/epidemiologia , Infecções por Picornaviridae/patologia , Infecções por Picornaviridae/virologia , Suínos , Doenças dos Suínos/patologia , Virulência
7.
Vet Res ; 50(1): 85, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31640784

RESUMO

The causative agent of ileitis, Lawsonia intracellularis, is commonly associated with diarrhea and reduced weight gain in growing pigs. The effect of in-feed probiotics on L. intracellularis infection dynamics was evaluated. In brief, 70 2.5-week-old-pigs were randomly divided into six groups with 10-20 pigs each. All pigs were fed an age appropriate base ration for the duration of the study, which was supplemented with one of three Bacillus strains including B. amyloliquefaciens (T01), B. licheniformis (T02) and B. pumilus (T03). Another group was orally vaccinated with a commercial live L. intracellularis vaccine (VAC) at 3 weeks of age. At 7 weeks of age, T01-LAW, T02-LAW, T03-LAW, VAC-LAW and the POS-CONTROL groups were challenged with L. intracellularis while the NEG-CONTROL pigs were not challenged. All pigs were necropsied 16 days later. By the time of inoculation, all VAC-LAW pigs had seroconverted and at necropsy 10-65% of the pigs in all other challenged groups were also seropositive. The results indicate a successful L. intracellularis challenge with highest bacterial DNA levels in POS-CONTROL pigs, VAC-LAW pigs and T01-LAW pigs. There was a delay in onset of shedding in T02-LAW and T03-LAW groups, which was reflected in less severe macroscopic and microscopic lesions, reduced intralesional L. intracellularis antigen levels and a lower area under the curve for bacterial shedding. Under the study conditions, two of the probiotics tested suppressed L. intracellularis infection. The obtained findings show the potential of probiotics in achieving antibiotic-free control of L. intracellularis.


Assuntos
Bacillus pumilus/química , Derrame de Bactérias/efeitos dos fármacos , Infecções por Desulfovibrionaceae/veterinária , Lawsonia (Bactéria)/efeitos dos fármacos , Probióticos/farmacologia , Doenças dos Suínos/tratamento farmacológico , Ração Animal/análise , Animais , Bacillus amyloliquefaciens/química , Bacillus licheniformis/química , Infecções por Desulfovibrionaceae/tratamento farmacológico , Infecções por Desulfovibrionaceae/microbiologia , Infecções por Desulfovibrionaceae/patologia , Dieta/veterinária , Lawsonia (Bactéria)/fisiologia , Distribuição Aleatória , Suínos , Doenças dos Suínos/microbiologia , Doenças dos Suínos/patologia
8.
C R Biol ; 342(5-6): 199-208, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31474523

RESUMO

The wear on the occlusal surfaces of male babirusa cheek teeth was evaluated in 53 skulls of Babyrousa babyrussa from Buru and the Sula Islands and 87 skulls of B. celebensis from Sulawesi, Indonesia. Based on the comparative lengths of their continually growing maxillary canine teeth, the skulls were divided into five 'age categories' (A-E). Numerical and symbolic codes representing tooth wear were applied to each pillar (cusp region) of the mandibular and maxillary permanent third and fourth premolar teeth, and the first, second and third permanent molar teeth. There was no significant difference between the tooth wear patters of skulls in groups A and B, or in groups C and D, and so these were amalgamated. There was close correspondence in wear patterns between each side of the mouth in both species and in each age group. The wear patterns of the mandibular and maxillary teeth, although not identical, were very similar, as were the wear patterns of both species. In group A+B for both species tooth wear was relatively slight, with the M1 teeth experiencing most relative wear. There was almost no wear of the M3 teeth. In group C+D substantial wear of upper and lower M1 was evident. In group E more widespread wear of the cheek teeth was seen, with increased severity of M1 tooth wear, yet there was comparatively much less M2 and M3 tooth wear. The pattern of cheek tooth wear of the Babyrousa spp. was different from that shown by Susscrofa. Differences in diet selection and processing were highlighted as potential contributing factors. The pattern of cheek tooth wear in male babirusa was not adequate for use to monitor their age.


Assuntos
Determinação da Idade pelos Dentes/métodos , Suínos , Erosão Dentária/patologia , Animais , Dente Canino/patologia , Dieta , Masculino , Reprodutibilidade dos Testes , Doenças dos Suínos/patologia , Dente/patologia
9.
Aust Vet J ; 97(11): 452-464, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31529470

RESUMO

BACKGROUND: Swine dysentery (SD) caused by Brachyspira hyodysenteriae is an important disease in Australia. AIM: The aim of this study is to evaluate the macrolide antibiotic kitasamycin for use in SD control. METHODS: The minimum inhibitory concentrations (MICs) of kitasamycin, tylosin and lincomycin for 32 Australian isolates of B. hyodysenteriae were evaluated. Mutations in the 23S rRNA gene were examined. Isolate '13' with a low kitasamycin MIC was used to challenge weaner pigs. Sixty pigs were housed in 20 pens each containing three pigs: pigs in four pens received 2 kg/tonne of a product containing kitasamycin (3.1% active) prophylactically in their food starting 4 days before B. hyodysenteriae challenge (group 1); pigs in four pens were challenged and received the same dose therapeutically once one pig in a pen showed diarrhoea (group 2); four pens were challenged and received 4 kg/tonne of the product therapeutically (group 3); four pens were challenged but not medicated (group 4); two pens were unmedicated and unchallenged (group 5) and two pens received 2 kg/tonne and were unchallenged (group 6). Pigs were monitored for B. hyodysenteriae excretion and disease. RESULTS: Macrolide resistance was widespread, and mutations in the 23S rRNA gene were identified in 23 isolates. Four isolates with kitasamycin MICs < 5 µg/mL were considered susceptible. Following experimental challenge, 10 of 12 unmedicated pigs developed SD. No pigs receiving kitasamycin prophylactical or therapeutically developed SD. Medicated pigs shed low numbers of B. hyodysenteriae in their faeces. CONCLUSIONS: Kitasamycin can help control SD in pigs infected with susceptible isolates of B. hyodysenteriae.


Assuntos
Antibacterianos/farmacologia , Brachyspira hyodysenteriae/efeitos dos fármacos , Disenteria Bacilar/veterinária , Infecções por Bactérias Gram-Negativas/veterinária , Kitasamicina/farmacologia , Doenças dos Suínos/tratamento farmacológico , Animais , Autopsia/veterinária , Modelos Animais de Doenças , Disenteria Bacilar/tratamento farmacológico , Disenteria Bacilar/microbiologia , Disenteria Bacilar/patologia , Genes de RNAr/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/patologia , Masculino , Testes de Sensibilidade Microbiana , Análise de Sequência de RNA , Suínos , Doenças dos Suínos/patologia , Austrália Ocidental
10.
Anim Sci J ; 90(11): 1475-1483, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31515907

RESUMO

The aim of this study was to identify the prevalence of pathological lesions in pigs from small-scale farms and to determine associations between pathological lesions and hematological parameters, and carcass and meat quality in slaughtered pigs. The study was conducted on 625 pigs (~115 kg) originating from 20 small-scale farms. Any signs of pneumonia, pleurisy, pericarditis, and liver milk spots were recorded as present or absent. Complete blood count was investigated. The following carcass quality parameters were measured: live, hot and cold carcass weights, cooling loss, dressing percentage, backfat thickness, and meatiness. Meat pH and temperature were measured 45 min postmortem. Of the 625 examined pigs, 41.8% had pneumonia, 23.5% pleurisy, 2.7% pericarditis, and 29.9% liver milk spots. The presence of pathological lesions in slaughtered pigs adversely affected hematological parameters, reduced live, hot and cold carcass weights, and meatiness and had deleterious effects on meat quality (higher pH45min and higher prevalence of dark, firm and dry meat). In conclusion, this study showed a high prevalence of pathological lesions in slaughtered pigs, indicating serious health problems in smallholder pig production systems. The presence of single and, especially, multiple pathological lesions in slaughtered pigs negatively affected hematological parameters, and carcass and meat quality.


Assuntos
Matadouros/estatística & dados numéricos , Qualidade dos Alimentos , Hepatopatias/epidemiologia , Hepatopatias/veterinária , Pericardite/epidemiologia , Pericardite/veterinária , Pleurisia/epidemiologia , Pleurisia/veterinária , Pneumonia/epidemiologia , Pneumonia/veterinária , Doenças dos Suínos/epidemiologia , Animais , Fazendas/estatística & dados numéricos , Hepatopatias/patologia , Pericardite/patologia , Pneumonia/patologia , Prevalência , Suínos , Doenças dos Suínos/patologia
11.
Vet Microbiol ; 235: 220-228, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31383305

RESUMO

The highly virulent porcine epidemic diarrhea virus (PEDV) variants cause the death of mainly neonatal piglets, but how the viruses spread within the gastro-intestinal tract in a temporal and spatial manner has remained poorly characterized but is critical to understand the viral pathogenesis. In this study, we used the Chinese PEDV epidemic strain BJ2011C as a model organism and took advantage of the newly developed RNAscope in situ hybridization technology to investigate the tempo-spatial infection dynamics in neonatal piglets. We found that the PEDV strain BJ2011C could quickly colonize the small intestine, which occurred in just 6 h post infection, with virus shedding starting at 6 hpi and peaking at 24 hpi. Jejunum was the first target tissue for infection and then ileum, followed by infrequent infection of duodenum. In these tissues, the virus nucleic acids were mainly present in the villous epithelial cells but not in crypt cells. Interestingly, the viral RNAs were not detectable by RNAscope in large intestines although tissue damages could be discerned by H & E staining. Overall, our results provide useful information about spread dynamics and tissue preference of PEDV epidemic strain BJ2011C.


Assuntos
Infecções por Coronavirus/patologia , Intestino Delgado/virologia , Vírus da Diarreia Epidêmica Suína/patogenicidade , RNA Viral/isolamento & purificação , Doenças dos Suínos/patologia , Animais , Animais Recém-Nascidos , Diarreia/veterinária , Diarreia/virologia , Células Epiteliais/virologia , Hibridização in Situ Fluorescente , Jejuno/citologia , Jejuno/virologia , Suínos , Doenças dos Suínos/virologia , Eliminação de Partículas Virais
12.
Prev Vet Med ; 169: 104690, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31311631

RESUMO

Taenia solium, a zoonotic tapeworm species of human and pigs, has been targeted by the World Health Organisation (WHO) for elimination in endemic areas of Africa, Latin America and some parts of Asia. Unfortunately, the assessment of control measures against T. solium is complicated by the lack of specificity of current immunodiagnostic techniques for diagnosis of porcine cysticercosis. Many authors have concluded that the prevalence of T. hydatigena in pigs in Africa is low and extensive epidemiological studies on T. solium cysticercosis in pigs have been carried out using serological tests that cannot differentiate the taeniid species. To estimate and compare the prevalence of T. solium and T. hydatigena in pigs in Cameroon, we examined 416 slaughtered pigs at a pig abattoir in Yaoundé city with the animals originating from several parts of the country. At post-mortem inspection, 35 pigs (8.4%; 95% Confidence Interval (CI), 5.9-11.5 %) were found infected exclusively with T. solium and 27 (6.5%; 95% CI, 4.3-9.3 %) infected exclusively with T. hydatigena metacestodes. One animal was infected with T. solium and T. hydatigena. A stochastic simulation model which took into account the sensitivity of dissection of the tongue, external masseters and heart for diagnosis of T. solium porcine cysticercosis (TMH dissection test) and examination of mesentery, surfaces of the intestines and liver to identify T. hydatigena cysticerci in slaughtered pigs was developed to estimate the prevalence of these taeniid species. The results revealed that the actual prevalence of T. solium and T. hydatigena in Cameroon were 24.8% (95% CI, 20.1-30.5%) and 19.2% (95% CI, 15.1-24.1%), respectively. This study reports the highest porcine T. hydatigena prevalence ever in Africa and adjusted the prevalence of porcine T. solium infection obtained with genus-specific Ag-ELISA (Dorny et al., 2000) in Cameroon due to the presence of T. hydatigena.


Assuntos
Cisticercose/veterinária , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/parasitologia , Taenia/isolamento & purificação , Matadouros , Animais , Camarões/epidemiologia , Cisticercose/epidemiologia , Cisticercose/parasitologia , Cisticercose/patologia , Geografia , Testes Imunológicos , Prevalência , Análise de Regressão , Suínos , Doenças dos Suínos/patologia , Taenia/imunologia
13.
Pol J Vet Sci ; 22(2): 345-353, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31269354

RESUMO

Tight junction proteins are important for the maintenance and repair of the intestinal mucosal barrier. The present study investigated relationships among tight junction protein gene expression, porcine epidemic diarrhea virus (PEDV) infection, and intestinal mucosal morphology in piglets. We compared the expression of six tight junction proteins (ZO-1, ZO-2, Occludin, Claudin-1, Claudin-4, and Claudin-5) between seven-day-old piglets infected with PEDV and normal piglets, as well as in PEDV-infected porcine intestinal epithelial cells (IPEC-J2). We also evaluated differences in mucosal morphology between PEDV-infected and normal piglets. The expression of six tight junction protein genes was lower in PEDV-infected piglets than in the normal animals. The expression of ZO-1, ZO-2, Occludin, and Claudin-4 in the intestine tissue was significantly lower (p⟨0.05) in PEDV-infected than in normal piglets. The expression of Claudin-5 in the jejunum was significantly lower in PEDV-infected piglets than in the normal animals (p⟨0.01). The expression of Claudin-1 and Claudin-5 genes in the ileum was significantly higher in PEDV-infected piglets than in normal piglets (p⟨0.01). Morphologically, the intestinal mucosa in PEDV-infected piglets exhibited clear pathological changes, including breakage and shedding of intestinal villi. In PEDV-infected IPEC-J2 cells, the mRNA expression of the six tight junction proteins showed a downward trend; in particular, the expression of the Occludin and Claudin-4 genes was significantly lower (p⟨0.01). These data suggest that the expression of these six tight junction proteins, especially Occludin and Claudin-4, plays an important role in maintaining the integrity of the intestinal mucosal barrier and resistance to PEDV infection in piglets.


Assuntos
Infecções por Coronavirus/veterinária , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos/virologia , Proteínas de Junções Íntimas/metabolismo , Animais , Linhagem Celular , Infecções por Coronavirus/virologia , Regulação da Expressão Gênica , Mucosa Intestinal/patologia , Suínos , Doenças dos Suínos/patologia , Proteínas de Junções Íntimas/genética
14.
BMC Vet Res ; 15(1): 186, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31164162

RESUMO

BACKGROUND: Melanosis of lymph nodes in black pigs has generally been related to regression of congenital melanoma and, occasionally, to ingestion of acorns. The aim of this manuscript is to confirm the hypothesis of a possible acquired acorn-related pseudomelanosis in the Nero Calabrese pig, a swine breed belonging to the group of Italian native breeds and whose coverage area corresponds to the region of Calabria, southern Italy. This pig is characterized by slow-growing subjects, producing, however, high quality meat suitable for the production of sausages and fine hams. The study was carried out on 142 normally slaughtered pigs. All organs were examined. Lymph nodes and intestine (jejunum) were sampled. Histochemistry was performed on deparaffinized histological sections to identify the cell types involved and to characterize the pigment stored. To further confirm the pigmentation disorder, immunohistochemistry was carried out. Total phenolic substances were identified in acorns through the use of a biochemical reaction. RESULTS: Lymph node pigmentation appears directly related to acorn ingestion, with a higher incidence in the group which was 70% natural fed (acorn of Quercus virgiliana). Moreover, findings obtained revealed how different amounts of phenolic substrates present in Q. virgiliana and Q. ilex acorns can influence the incidence of such exogenous pigmentation. CONCLUSION: The findings obtained in this study confirm the acquired nature of the melanin-like pigmentation detected in lymph nodes from acorn-fed swine. Acquired pigmentation must be differentiated from true melanosis as well as from melanosis related to tumor regression of congenital melanoma. This thesaurismosis can be proposed as a marker of wellbeing and quality, confirming that the pigs have been bred and fed in natural conditions.


Assuntos
Ração Animal , Hiperpigmentação/veterinária , Doenças Linfáticas/veterinária , Quercus , Sementes , Doenças dos Suínos/etiologia , Animais , Feminino , Hiperpigmentação/etiologia , Hiperpigmentação/patologia , Linfonodos/patologia , Doenças Linfáticas/etiologia , Doenças Linfáticas/patologia , Masculino , Suínos , Doenças dos Suínos/patologia
15.
BMC Vet Res ; 15(1): 218, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31248411

RESUMO

BACKGROUND: Antimicrobial use (AMU) in livestock is a debated topic, mainly due to the risk of associated development of antimicrobial resistance. There is focus on reducing AMU in the Danish pig production, which accounts for the largest proportion of AMU for animals in Denmark. Due to special restriction on AMU in organic pig production, the AMU in organic pig production is lower than in conventional pig production. There is concern that reduced AMU could jeopardize animal health and welfare, if it reflects insufficient treatment of sick animals, which might be reflected by the prevalence and types of lesions found at meat inspection. However, little is known about the associations between AMU and meat inspection findings in pigs from organic farms. Furthermore, excess amount of antimicrobial product after a treatment cannot be re-prescribed in organic pig herds. The initial prescription is recorded in the national database VetStat, but the unused amount is not deducted leading to uncertainty when reporting AMU. The objectives of this study were to 1) describe AMU patterns based on prescription data for organic pig production and compare with those of the conventional pig production for year 2016, 2) study the associations between herd-level AMU prescription data and meat inspection data for organic pig herds and 3) validate herd-level AMU prescription data in VetStat against treatment records collected on-farm in organic Danish pig herds. RESULTS AND CONCLUSIONS: Gastrointestinal indications account for the largest proportion of AMU in both organic pig herds (65 and 54% of treatment doses for weaners and finishers, respectively) and conventional pig herds (80 and 68% of doses for weaners and finishers, respectively). A larger proportion is prescribed for respiratory indications in organic than conventional weaners and arthropathic indications in finishers. No associations between AMU and meat inspection data were found. This needs further investigation as the prevalence of lesions at slaughter was slightly (non-significantly) higher in herds with no registered AMU than with AMU prescriptions. Only 8 out of 31 herds had recorded their AMU sufficiently detailed to compare, and using VetStat as a proxy for AMU led to 9-88% overestimation of the actual use in 7 out of these 8 herds and 120% underestimation in one herd.


Assuntos
Anti-Infecciosos/uso terapêutico , Agricultura Orgânica , Medicamentos sob Prescrição/uso terapêutico , Doenças dos Suínos/tratamento farmacológico , Matadouros , Animais , Bases de Dados Factuais , Dinamarca , Revisão de Uso de Medicamentos , Registros Eletrônicos de Saúde , Suínos , Doenças dos Suínos/patologia
16.
PLoS Negl Trop Dis ; 13(6): e0007408, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31237878

RESUMO

The definitive method for diagnosis of porcine cysticercosis is the detection of cysticerci at necropsy. Cysts are typically located in the striated muscle and brain. Until recently Taenia solium cysticerci have not been definitively identified in other tissue locations, despite several comprehensive investigations having been undertaken which included investigation of body organs other than muscle and brain. Recently a study conducted in Zambia reported 27% infection with T. solium in the liver of pigs with naturally acquired porcine cysticercosis, as well as some T. solium infection in the lungs and spleen of some animals. We investigated the cause of lesions in sites other than the muscle or brain in a total of 157 pigs from T. solium endemic regions of Uganda and Nepal which were subjected to extensive investigations at necropsy. Lesions which had the potential to be caused by T. solium were characterised by macroscopic and microscopic examination, histology as well as DNA characterisation by PCR-RFLP and sequencing. Lesions were confirmed as being caused by Taenia hydatigena (both viable and non-viable), by T. asiatica and Echinococcus granulosus (in Nepal) and nematode infections. No T. solium-related lesions or cysticerci were identified in any tissue other than muscle and brain. It is recommended that future evaluations of porcine cysticercosis in aberrant tissue locations include DNA analyses that take appropriate care to avoid the possibility of contamination of tissue specimens with DNA from a different tissue location or a different animal. The use of appropriate control samples to confirm the absence of cross-sample contamination is also recommended.


Assuntos
Estruturas Animais/patologia , Estruturas Animais/parasitologia , Cisticercose/veterinária , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/patologia , Taenia solium/isolamento & purificação , Animais , Autopsia , Cisticercose/diagnóstico , Cisticercose/parasitologia , Cisticercose/patologia , Histocitoquímica , Nepal , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Análise de Sequência de DNA , Suínos , Doenças dos Suínos/parasitologia , Uganda
17.
J Microbiol Biotechnol ; 29(6): 863-876, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31091863

RESUMO

Farm animals such as piglets are often affected by environmental stress, which can disturb the gut ecosystem. Antibiotics were commonly used to prevent diarrhea in weaned piglets, but this was banned by the European Union due to the development of antibiotic resistance. However, the use of probiotics instead of antibiotics may reduce the risk posed by pathogenic microorganisms and reduce the incidence of gastrointestinal diseases. Therefore, this study was conducted to investigate the effects of Lactobacillus casei Zhang on the mechanical barrier and immune function of early-weaned piglets infected using Escherichia coli K88 based on histomorphology and immunology. Fourteen-day-old weaned piglets were divided into a control group and experimental groups that were fed L. casei Zhang and infected with E. coli K88 with or without prefeeding and/or postfeeding of L. casei Zhang. The L. casei Zhang dose used was 107 CFU/g diet. Jejunum segments were obtained before histological, immunohistochemical, and western blot analyses were performed. In addition, the relative mRNA expression of toll receptors and cytokines was measured. Piglets fed L. casei Zhang showed significantly increased jejunum villus height, villus height-crypt depth ratio, muscle thickness, and expression of proliferating cell nuclear antigen and tight junction proteins ZO-1 and occludin. The use of L. casei Zhang effectively reduced intestinal inflammation after infection. We found that L. casei Zhang feeding prevented the jejunum damage induced by E. coli K88, suggesting that it may be a potential alternative to antibiotics for preventing diarrhea in early-weaned piglets.


Assuntos
Infecções por Escherichia coli/veterinária , Expressão Gênica/efeitos dos fármacos , Mucosa Intestinal/fisiologia , Jejuno/efeitos dos fármacos , Lactobacillus casei/fisiologia , Probióticos/administração & dosagem , Doenças dos Suínos/prevenção & controle , Animais , Citocinas/genética , Suplementos Nutricionais , Escherichia coli Enterotoxigênica/fisiologia , Infecções por Escherichia coli/patologia , Infecções por Escherichia coli/prevenção & controle , Fatores Imunológicos/genética , Fatores Imunológicos/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Jejuno/patologia , Ocludina/genética , Ocludina/metabolismo , Probióticos/farmacologia , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Suínos , Doenças dos Suínos/patologia , Receptores Toll-Like/genética , Desmame , Proteína da Zônula de Oclusão-1/genética , Proteína da Zônula de Oclusão-1/metabolismo
18.
Animal ; 13(11): 2463-2472, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31084646

RESUMO

Dietary protein restriction is one of the effective ways to reduce post-weaning diarrhoea and intestinal fermentation in piglets, but it may also reduce growth performance. The compensatory growth induced by subsequent protein realimentation may solve the issue. However, little research has been done on the impact of protein realimentation on the gut. In this study, the effects of protein restriction and realimentation on ileal morphology, ileal microbial composition and metabolites in weaned piglets were investigated. Thirty-six 28-day-old weaned piglets with an average body weight of 6.47 ± 0.04 kg were randomly divided into a control group and a treatment group. The CP level in the diet of the control group was 18.83% for the entire experimental period. The piglets in the treatment group were fed 13.05% CP between days 0 and 14 and restored to a diet of 18.83% CP for days 14 to 28. On day 14 and 28, six pigs from each group were sacrificed and sampled. It was found that the abundance of Lactobacillus and Salmonella in the ileal digesta was significantly lower in the treatment group than the control group on day 14, whereas the abundance of Clostridium sensu stricto 1, Streptococcus, Halomonas and Pseudomonas significantly increased in the ileal digesta of the treatment group on day 14 compared with the control group. In addition, reduced concentrations of lactic acid, total short-chain fatty acids (total SCFAs), total branched chain fatty acids, ammonia and impaired ileal morphology and mucosal barrier were observed in the treatment group on day 14. However, diarrhoea levels decreased in the treatment group throughout the experiment. During the succedent protein realimentation stage, the treatment group demonstrated compensatory growth. Compared with the control group, the treatment group showed increased abundance of Lactobacillus and reduced abundance of Salmonella, Halomonas and Pseudomonas in the ileum on day 28. The concentrations of lactic acid and total SCFAs increased significantly, whereas the concentration of ammonia remained at a lower level in the treatment group on day 28 compared with the control group. Overall, protein realimentation could improve ileal morphology and barrier functions and promote ileal digestive and absorptive functions. In conclusion, ileal microbial composition and metabolites could change according to dietary protein restriction and realimentation and eventually influence ileal morphology and barrier functions.


Assuntos
Ração Animal/análise , Diarreia/veterinária , Dieta com Restrição de Proteínas/veterinária , Doenças dos Suínos/microbiologia , Suínos/fisiologia , Amônia/análise , Animais , Diarreia/microbiologia , Diarreia/patologia , Dieta/veterinária , Proteínas na Dieta/metabolismo , Digestão , Ácidos Graxos/análise , Ácidos Graxos Voláteis/análise , Íleo/microbiologia , Íleo/patologia , Ácido Láctico/análise , Lactobacillus/isolamento & purificação , Distribuição Aleatória , Salmonella/isolamento & purificação , Suínos/microbiologia , Doenças dos Suínos/patologia , Desmame
19.
Vet Pathol ; 56(5): 732-742, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31060473

RESUMO

Articular osteochondrosis (OC) arises due to vascular failure and ischemic chondronecrosis. The aim of the study was to describe the histological and computed tomographic (CT) characteristics of changes in the distal femoral physis of pigs, to determine if they represented OC lesions and if the pathogenesis was the same as for articular OC. The material included 19 male Landrace pigs bred for predisposition to OC. One or 2 pigs were euthanized and CT-scanned at 2-week intervals from 82 to 180 days of age. Material from 10 pigs was available for histological validation. The CT scans revealed 31 lesions confirmed in 3 planes and 1 additional macroscopically visible lesion confirmed in 2 CT planes. Twelve of the lesions were histologically validated. All lesions were compatible with OC. Cartilage canal and eosinophilic streak morphological changes corresponded to failure of end arteries coursing from the epiphysis, toward the metaphysis. The location of lesions was compatible with failure at the point of vessel incorporation into bone. Vascular failure was associated with retention of viable hypertrophic chondrocytes and delayed ossification but not cartilage necrosis. Lesion width ranged from 1.1% to 45.6% of the physis. Several lesions were expected to resolve due to small size and evidence of CT-identifiable, reparative ossification. Angular limb deformity was not detected in any pig. The pathogenesis of physeal OC started with vascular failure that was morphologically identical to articular OC. The heritable predisposition may therefore be the same. The association between lesions and limb deformity should be studied further in older pigs in future.


Assuntos
Cartilagem Articular/irrigação sanguínea , Lâmina de Crescimento/irrigação sanguínea , Osteocondrose/veterinária , Doenças dos Suínos/patologia , Animais , Osso e Ossos/patologia , Cartilagem Articular/patologia , Fêmur/patologia , Lâmina de Crescimento/patologia , Masculino , Osteocondrose/patologia , Suínos , Doenças dos Suínos/etiologia
20.
J Comp Pathol ; 168: 25-29, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31103055

RESUMO

Peripheral nerve sheath tumours are rare in pigs. In the present case, a juvenile female hybrid pig showed a solitary, pigmented, cutaneous mass. Histologically, it consisted of clustered melanin-laden, epithelioid cells as well as spindle cells forming bundles and nodules. The latter were surrounded by perineurial-like cells. Single Wagner-Meissner-like corpuscles were present. Immunohistochemically, the epithelioid cells expressed S100 protein, melan A and the p75 neurotrophin receptor (p75NTR). The spindle cells expressed S100, sex determining region Y-box 2, p75NTR, Krox20, growth associated protein 43 and glial fibrillary acidic protein. Perineurial-like cells were positive for p75NTR, α-smooth muscle actin and cytokeratin. Taken together, the histological und immunohistochemical findings support the diagnosis of a cutaneous pigmented neurofibroma.


Assuntos
Neurofibroma/veterinária , Neoplasias Cutâneas/veterinária , Doenças dos Suínos/patologia , Animais , Imuno-Histoquímica , Pigmentação , Suínos
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