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Veikko K. Tuovinen - One of the best experts on this subject based on the ideXlab platform.
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Eradication of porcine sarcoptic mange within a health declared production model
Acta Veterinaria Scandinavica, 2020Co-Authors: Mari Heinonen, Set Bornstein, Riikka Kolhinen, Hannu Saloniemi, Veikko K. TuovinenAbstract:The success of a large-scale eradication programme against sarcoptic mange was evaluated in piglet producing herds belonging to the health class LSO 2000. These farms are monitored to be free from sarcoptic mange, swine enzootic pneumoniae, swine dysentery and progressive atrophic rhinitis. The local veterinarians were instructed to eradicate sarcoptic mange from the herds by 2 ivermectin injections 14 days apart or 3 treatments with phoxim pour-on 6 days apart before the farms were able to join the health class. The study consisted of a questionnaire administered to the farmers, farm visits and follow-ups associated with the regular control of the health class. A questionnaire was sent to all of the 379 accepted farrowing farms. Altogether 323 farmers had initiated an eradication programme at least 7 months before the questionnaire was distributed and 96% of them believed that the mange eradication programme had been successful. In most of the successful herds (90%), the local veterinarian had treated the animals by the recommended methods, and the majority of the farmers (88%) had cleaned and sprayed the pens with insecticides on the days of treatment. Three out of the 7 unsuccessful farms had employed methods other than those recommended. Twenty-five herds were randomly selected for an intensified control. The rubbing index was < or = 0.1 in all herds visited, indicating freedom from mange. Sows or gilts, 15-20 animals per farm, were skin scraped and no Sarcoptes scabiei was found. The same animals were blood sampled and serum antibodies to S. scabiei were measured by an indirect ELISA. All except 1 farm had low optical density (OD) values in most of the samples. The owner of that farm had become uncertain about the mange status of the herd and had recently retreated all animals with acaricides. The number of complaints about mange in the finishing units buying health class Feeder Pigs was low. The study demonstrates that it is possible to run an eradication programme against sarcoptic mange, in which a large number of farmers together with their veterinarians participate. It is possible to eradicate mange not only at the herd but also at the population level. The ELISA test employed proved to be a possible tool to monitor the efficacy of mange-eradication programmes.
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the effects of health classification and housing and management of Feeder Pigs on performance and meat inspection findings of all in all out swine finishing herds
Preventive Veterinary Medicine, 2001Co-Authors: Mari Heinonen, Hannu Saloniemi, Y T Grohn, Elina Eskola, Veikko K. TuovinenAbstract:Abstract The effects of health classification and of housing and management on performance and meat inspection findings were studied in 166 all-in–all-out finishing herds in Finland in 1995 and 1998. Producers could buy either health-classified (certified free of certain diseases) or standard-class Pigs for their farms. Herds that had attained a certain level of housing and management were eligible to join the LSO 2000 management system for finishing herds. In 1995, none of the study herds were LSO 2000 units. In 1998, 76 of them had become LSO 2000 units, while 90 had remained as non-LSO 2000 units. Continuous outcome variables (daily gain and time in the finishing unit) were analysed with a mixed-model procedure with repeated measurements from the same farms. Discrete variables were analysed either with Poisson regression (mortality, whole- and partial-carcass condemnations, organ condemnations, arthritis, abscesses) or logistic regression (liver condemnations, pneumonia, pleuritis). The models were adjusted for the year, size of the herd and the average slaughter weight of the batch. The benefits obtained by the health classification of the Feeder Pigs included a substantial increase in daily gain (37 g, about 5%) and decrease in time in the finishing unit (4 days, about 4%), decrease in mortality (odds ratio, OR 0.68), a substantial decrease in pneumonia (OR 0.37) and pleuritis (OR 0.60), and a substantial decrease in liver (OR 0.45) and organ (OR 0.72) condemnations. Classification of the Pigs did not have an effect on the prevalence of whole-carcass condemnations, arthritis or abscesses. The health-classified Pigs had, unexpectedly, more partial-carcass condemnations (OR 1.15) than the standard-class Pigs. The obtained benefits of the LSO 2000 units were an increase in daily gain (14 g, about 2%), decrease in time in the finishing unit (2 days, about 2%), a decrease in mortality (OR 0.69) and a decrease in whole-carcass (OR 0.69) and partial-carcass (OR 0.81) condemnations. The LSO 2000 units did not have any advantage over the non-LSO 2000 units in their prevalence of liver or organ condemnations, arthritis, abscesses, pneumonia or pleuritis.
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detectability and prevalence of brachyspira species in herds rearing health class Feeder Pigs in finland
Veterinary Record, 2000Co-Authors: Mari Heinonen, Hannu Saloniemi, M Fossi, J P Jalli, Veikko K. TuovinenAbstract:Faeces samples were taken three times at two-week intervals, from the farrowing units of four herds of known Brachyspira (formerly Serpulina) status and one of unknown Brachyspira status. Brachyspira hyodysenteriae, Brachyspira pilosicoli, Brachyspira intermedia and Brachyspira group III were isolated from the faecal samples from the weaners in the herds using either a maximum of 50 ppm of olaquindox or no feed additives. The detection rates were relatively consistent. However, B hyodysenteriae was not detected at one sampling in a known positive herd. The prevalence of Brachyspira species was also studied in Feeder Pigs originating from LSO 2000 health class farrowing units, comparable with specific pathogen-free herds. These farms were free from swine dysentery, sarcoptic mange, swine enzootic pneumonia and progressive atrophic rhinitis. Fifty of 428 herds were sampled once. B hyodysenteriae was not isolated from any of them, but B intermedia, B pilosicoli and Brachyspira group III were isolated from five, 14 and 37 of the herds, respectively. The detection of Brachyspira species did not relate to the prevalence of diarrhoea in the herds, as judged by the farmers. The herds using carbadox (40 to 50 ppm) had a lower prevalence of Brachyspira species than those using olaquindox (40 to 50 ppm).
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health classification of multisource Feeder Pigs a field trial
Preventive Veterinary Medicine, 1994Co-Authors: Veikko K. Tuovinen, Y T Grohn, Barbara E StrawAbstract:Abstract Health classification of purchased multisource Feeder Pigs was tested in a field trial. Feeder Pigs transported to the all-in all-out finishing units were classified according to the health status of the source herd. Health class (HC) Feeder Pigs originated from the farrowing units which were free of clinical signs of respiratory diseases and swine dysentery, and free of Mycoplasma hyopneumoniae antibodies. Performance and meat inspection results of 20 HC and 384 conventional control batches (health status unknown) were analysed. Previous batches from the same herds were used to adjust the differences between HC and conventional batches by herd effect. Mean average daily gain (ADG) was 839 g in the HC group and 803 g in the conventional group. ADG improvement from previous batch to test batch was 28 g better ( P Mortality in the HC batches was 20% less ( P P Partial carcass condemnations (PCC) were 1.4 times more frequent in the HC group than in the control group ( P The greatest differences were found in pneumonia and pleurisy. Pneumonia findings were almost nine times more frequent ( P P
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Health classification of multisource Feeder Pigs—a field trial
Preventive Veterinary Medicine, 1994Co-Authors: Veikko K. Tuovinen, Y T Grohn, Barbara E StrawAbstract:Abstract Health classification of purchased multisource Feeder Pigs was tested in a field trial. Feeder Pigs transported to the all-in all-out finishing units were classified according to the health status of the source herd. Health class (HC) Feeder Pigs originated from the farrowing units which were free of clinical signs of respiratory diseases and swine dysentery, and free of Mycoplasma hyopneumoniae antibodies. Performance and meat inspection results of 20 HC and 384 conventional control batches (health status unknown) were analysed. Previous batches from the same herds were used to adjust the differences between HC and conventional batches by herd effect. Mean average daily gain (ADG) was 839 g in the HC group and 803 g in the conventional group. ADG improvement from previous batch to test batch was 28 g better ( P Mortality in the HC batches was 20% less ( P P Partial carcass condemnations (PCC) were 1.4 times more frequent in the HC group than in the control group ( P The greatest differences were found in pneumonia and pleurisy. Pneumonia findings were almost nine times more frequent ( P P
Barbara E Straw - One of the best experts on this subject based on the ideXlab platform.
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characterization of group c rotaviruses associated with diarrhea outbreaks in Feeder Pigs
Journal of Clinical Microbiology, 1999Co-Authors: Kyeongok Chang, Barbara E Straw, Linda J SaifAbstract:Feces and serum specimens were collected from three farms in Michigan on which ∼50-lb (8- to 9-week-old) Pigs experienced diarrhea just after placement into all-in-all-out finishing barns. The clinical signs (profuse watery diarrhea lasting about 2 weeks and no vomiting) were similar on all farms, and the morbidity rate was high (ranging from 60 to 80%) but without mortality. Eleven diarrheic fecal samples from the farms were tested for group A and C rotaviruses by immune electron microscopy (IEM) and various assays. IEM indicated that the fecal samples reacted only with antiserum against group C rotaviruses, and polyacrylamide gel electrophoresis indicated that the samples had characteristic genomic electropherotypes for group C rotavirus. Group C rotavirus was detected by cell culture immunofluorescence (CCIF) tests in nine fecal samples, but no group A rotavirus was detected by enzyme-linked immunosorbent assay or CCIF. By reverse transcription (RT)-PCR, all 11 fecal samples were positive for group C rotaviruses, with only 2 samples positive for group A rotaviruses. However, a second amplification of RT-PCR products using nested primers detected group A rotaviruses in all samples. Analysis of nucleotide and deduced amino acid sequences of the RT-PCR product (partial-length VP7) of the group C rotavirus showed 87.2 to 91% nucleotide identity and 92.6 to 95.9% amino acid identity among two strong samples from the different farms and the Cowden strain of porcine group C rotavirus. All nine convalescent-phase serum samples tested had neutralizing antibodies to the Cowden strain, and the majority of them had neutralizing antibody against group A rotaviruses (OSU or/and Gottfried strains) by fluorescent focus neutralization tests. Although group C rotaviruses have been reported as a cause of sporadic diarrhea in suckling or weanling Pigs, to our knowledge, this is the first report of epidemic diarrhea outbreaks associated with group C rotavirus in older Pigs.
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health classification of multisource Feeder Pigs a field trial
Preventive Veterinary Medicine, 1994Co-Authors: Veikko K. Tuovinen, Y T Grohn, Barbara E StrawAbstract:Abstract Health classification of purchased multisource Feeder Pigs was tested in a field trial. Feeder Pigs transported to the all-in all-out finishing units were classified according to the health status of the source herd. Health class (HC) Feeder Pigs originated from the farrowing units which were free of clinical signs of respiratory diseases and swine dysentery, and free of Mycoplasma hyopneumoniae antibodies. Performance and meat inspection results of 20 HC and 384 conventional control batches (health status unknown) were analysed. Previous batches from the same herds were used to adjust the differences between HC and conventional batches by herd effect. Mean average daily gain (ADG) was 839 g in the HC group and 803 g in the conventional group. ADG improvement from previous batch to test batch was 28 g better ( P Mortality in the HC batches was 20% less ( P P Partial carcass condemnations (PCC) were 1.4 times more frequent in the HC group than in the control group ( P The greatest differences were found in pneumonia and pleurisy. Pneumonia findings were almost nine times more frequent ( P P
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Health classification of multisource Feeder Pigs—a field trial
Preventive Veterinary Medicine, 1994Co-Authors: Veikko K. Tuovinen, Y T Grohn, Barbara E StrawAbstract:Abstract Health classification of purchased multisource Feeder Pigs was tested in a field trial. Feeder Pigs transported to the all-in all-out finishing units were classified according to the health status of the source herd. Health class (HC) Feeder Pigs originated from the farrowing units which were free of clinical signs of respiratory diseases and swine dysentery, and free of Mycoplasma hyopneumoniae antibodies. Performance and meat inspection results of 20 HC and 384 conventional control batches (health status unknown) were analysed. Previous batches from the same herds were used to adjust the differences between HC and conventional batches by herd effect. Mean average daily gain (ADG) was 839 g in the HC group and 803 g in the conventional group. ADG improvement from previous batch to test batch was 28 g better ( P Mortality in the HC batches was 20% less ( P P Partial carcass condemnations (PCC) were 1.4 times more frequent in the HC group than in the control group ( P The greatest differences were found in pneumonia and pleurisy. Pneumonia findings were almost nine times more frequent ( P P
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The prevalence of some economically important swine diseases in farrowing units in southwestern Finland
Preventive Veterinary Medicine, 1994Co-Authors: Veikko K. Tuovinen, Y T Grohn, Katri H. Levonen, Barbara E StrawAbstract:Abstract The prevalence and geographical distribution of some economically important swine diseases were surveyed in 114 randomly selected farrowing units which had a contract with Southwestern Finland's Cooperative Slaughterhouse (LSO) for producing Feeder Pigs to be delivered to the all in-all out finishing units. The focus was on infectious diseases which could be transmitted to the finishing units with delivered growers, and which might have some influence on partial carcass condemnations (PCC) in meat inspection. Farm visits were done by a veterinarian (senior author) assisted by a technician. Colostrum samples (average 22 per herd) were taken in 100 herds, and analyzed for Actinobacillus pleuropneumoniae (A. pleur) and Mycoplasma hyopneumoniae (M.hyo) antibodies by enzyme-linked immunosorbent assays (ELISAs). Only nine of 114 herds were judged to be free of mange. It was concluded that all finishing units received mange-infected Feeder Pigs each time the unit was filled. One or more acute erysipelas outbreaks had occurred in every fifth herd during the previous year. The risk of a finishing unit receiving Feeder Pigs carrying erysipelas was considered to be high. Swine dysentery ( Serpulina hyodysenteriae ) was not found to be a problem in the LSO area. Clostridium perfringens type C enteritis was found in eight (7%) herds. Seven of these herds were located in those supply areas where the PCC percentage of Feeder Pigs was high. In spite of statistical connection no causality between this disease and PCC was presumed. There were no previous diagnoses of respiratory diseases but spontaneous coughing was observed in 5% of the herds. Provocation testing induced coughing in 22% of herds but not serious coughing in any herd. Managers had observed coughing in 15% of herds. Ninety-one herds were positive in a colostrum ELISA for A. pleur antibodies, and eight herds were positive for M.hyo antibodies. A.pleur-positive herds had several positive or samples suspected of being positive in each herd bu M.hyo-positive herds had only one or two positive or suspected samples per herd. Six of the M.hyo herds were located in the high PCC area, two in the average PCC area and none in the low PCC area. M.hyo was suggested to be one of the possible explanations for geographical variation of PCC. Atrophic rhinitis was not considered to be of importance in LSO.
Mari Heinonen - One of the best experts on this subject based on the ideXlab platform.
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Eradication of porcine sarcoptic mange within a health declared production model
Acta Veterinaria Scandinavica, 2020Co-Authors: Mari Heinonen, Set Bornstein, Riikka Kolhinen, Hannu Saloniemi, Veikko K. TuovinenAbstract:The success of a large-scale eradication programme against sarcoptic mange was evaluated in piglet producing herds belonging to the health class LSO 2000. These farms are monitored to be free from sarcoptic mange, swine enzootic pneumoniae, swine dysentery and progressive atrophic rhinitis. The local veterinarians were instructed to eradicate sarcoptic mange from the herds by 2 ivermectin injections 14 days apart or 3 treatments with phoxim pour-on 6 days apart before the farms were able to join the health class. The study consisted of a questionnaire administered to the farmers, farm visits and follow-ups associated with the regular control of the health class. A questionnaire was sent to all of the 379 accepted farrowing farms. Altogether 323 farmers had initiated an eradication programme at least 7 months before the questionnaire was distributed and 96% of them believed that the mange eradication programme had been successful. In most of the successful herds (90%), the local veterinarian had treated the animals by the recommended methods, and the majority of the farmers (88%) had cleaned and sprayed the pens with insecticides on the days of treatment. Three out of the 7 unsuccessful farms had employed methods other than those recommended. Twenty-five herds were randomly selected for an intensified control. The rubbing index was < or = 0.1 in all herds visited, indicating freedom from mange. Sows or gilts, 15-20 animals per farm, were skin scraped and no Sarcoptes scabiei was found. The same animals were blood sampled and serum antibodies to S. scabiei were measured by an indirect ELISA. All except 1 farm had low optical density (OD) values in most of the samples. The owner of that farm had become uncertain about the mange status of the herd and had recently retreated all animals with acaricides. The number of complaints about mange in the finishing units buying health class Feeder Pigs was low. The study demonstrates that it is possible to run an eradication programme against sarcoptic mange, in which a large number of farmers together with their veterinarians participate. It is possible to eradicate mange not only at the herd but also at the population level. The ELISA test employed proved to be a possible tool to monitor the efficacy of mange-eradication programmes.
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Eradication of Mycoplasma hyopneumoniae from a swine finishing herd without total depopulation.
Veterinary Journal, 2010Co-Authors: Mari Heinonen, Tapio Laurila, Gabriele Vidgren, Katri LevonenAbstract:Abstract Using vaccination and medication, Mycoplasma hyopneumoniae (Mhyo) was eradicated from a finishing herd without total depopulation. Altogether 3243 Feeder Pigs originating from Mhyo-free herds were vaccinated once using an inactivated, adjuvanted vaccine before transporting them to a Mhyo-infected finishing herd. The Mhyo-infected groups of Pigs were medicated with antimicrobial agents at the time of the arrival of the first groups of Mhyo-free, vaccinated Feeder Pigs. The groups were operated with an all-in–all-out method in rooms with separate ventilation and slurry disposal systems. Thereafter the farmer purchased only non-vaccinated Feeder Pigs originating from Mhyo-free sow herds. Serology gave no positive results for 5.5 years and it was concluded that the eradication programme had been successful in producing a Mhyo-free herd without total depopulation.
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the effects of health classification and housing and management of Feeder Pigs on performance and meat inspection findings of all in all out swine finishing herds
Preventive Veterinary Medicine, 2001Co-Authors: Mari Heinonen, Hannu Saloniemi, Y T Grohn, Elina Eskola, Veikko K. TuovinenAbstract:Abstract The effects of health classification and of housing and management on performance and meat inspection findings were studied in 166 all-in–all-out finishing herds in Finland in 1995 and 1998. Producers could buy either health-classified (certified free of certain diseases) or standard-class Pigs for their farms. Herds that had attained a certain level of housing and management were eligible to join the LSO 2000 management system for finishing herds. In 1995, none of the study herds were LSO 2000 units. In 1998, 76 of them had become LSO 2000 units, while 90 had remained as non-LSO 2000 units. Continuous outcome variables (daily gain and time in the finishing unit) were analysed with a mixed-model procedure with repeated measurements from the same farms. Discrete variables were analysed either with Poisson regression (mortality, whole- and partial-carcass condemnations, organ condemnations, arthritis, abscesses) or logistic regression (liver condemnations, pneumonia, pleuritis). The models were adjusted for the year, size of the herd and the average slaughter weight of the batch. The benefits obtained by the health classification of the Feeder Pigs included a substantial increase in daily gain (37 g, about 5%) and decrease in time in the finishing unit (4 days, about 4%), decrease in mortality (odds ratio, OR 0.68), a substantial decrease in pneumonia (OR 0.37) and pleuritis (OR 0.60), and a substantial decrease in liver (OR 0.45) and organ (OR 0.72) condemnations. Classification of the Pigs did not have an effect on the prevalence of whole-carcass condemnations, arthritis or abscesses. The health-classified Pigs had, unexpectedly, more partial-carcass condemnations (OR 1.15) than the standard-class Pigs. The obtained benefits of the LSO 2000 units were an increase in daily gain (14 g, about 2%), decrease in time in the finishing unit (2 days, about 2%), a decrease in mortality (OR 0.69) and a decrease in whole-carcass (OR 0.69) and partial-carcass (OR 0.81) condemnations. The LSO 2000 units did not have any advantage over the non-LSO 2000 units in their prevalence of liver or organ condemnations, arthritis, abscesses, pneumonia or pleuritis.
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detectability and prevalence of brachyspira species in herds rearing health class Feeder Pigs in finland
Veterinary Record, 2000Co-Authors: Mari Heinonen, Hannu Saloniemi, M Fossi, J P Jalli, Veikko K. TuovinenAbstract:Faeces samples were taken three times at two-week intervals, from the farrowing units of four herds of known Brachyspira (formerly Serpulina) status and one of unknown Brachyspira status. Brachyspira hyodysenteriae, Brachyspira pilosicoli, Brachyspira intermedia and Brachyspira group III were isolated from the faecal samples from the weaners in the herds using either a maximum of 50 ppm of olaquindox or no feed additives. The detection rates were relatively consistent. However, B hyodysenteriae was not detected at one sampling in a known positive herd. The prevalence of Brachyspira species was also studied in Feeder Pigs originating from LSO 2000 health class farrowing units, comparable with specific pathogen-free herds. These farms were free from swine dysentery, sarcoptic mange, swine enzootic pneumonia and progressive atrophic rhinitis. Fifty of 428 herds were sampled once. B hyodysenteriae was not isolated from any of them, but B intermedia, B pilosicoli and Brachyspira group III were isolated from five, 14 and 37 of the herds, respectively. The detection of Brachyspira species did not relate to the prevalence of diarrhoea in the herds, as judged by the farmers. The herds using carbadox (40 to 50 ppm) had a lower prevalence of Brachyspira species than those using olaquindox (40 to 50 ppm).
Maurice Pensaert - One of the best experts on this subject based on the ideXlab platform.
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Efficacy testing of a modified live PRRSV vaccine using the clinical synergy between PRRSV and bacterial lipopolysaccharides
Proc 17th Congress IPVS Ames Iowa USA, 2002Co-Authors: G Labarque, K Van Reeth, Hans Nauwynck, Tibor Magyar, F. Kovacs, Maurice PensaertAbstract:Introduction and Objectives Porcine reproductive and respiratory syndrome virus (PRRSV) plays an important role in multi-factorial respiratory disease problems in the field. The economical impact of these problems has stimulated the development of PRRSV vaccines. Currently, several modified live PRRSV vaccines are commercially available for use in Feeder Pigs. Since these vaccines do not provide a complete virological protection upon challenge (1,3), it is not excluded that the residual replication of wild-type virus in the lungs upon a field infection may still predispose for the appearance of multi-factorial respiratory disease problems. Efficacy tests based merely on reduction in virus replication may not be sufficient and therefore, an alternative is here proposed. It was demonstrated that a PRRSV infection predisposes Pigs for respiratory signs when they are subsequently exposed to bacterial lipopolysaccharides (LPS) (2). It was the purpose of the present study to apply this dual inoculation method in an attempt to test the clinical efficacy of modified live PRRSV vaccines. The question was asked if the residual challenge virus replication in the lungs of vaccinated Pigs also predisposes for respiratory signs when such Pigs are exposed to LPS. Materials and Methods Thirty-five PRRSV-negative conventional Pigs were used in two experiments. The experimental design is presented in Table 1. The U.S. vaccine strain JJ1882 (Ingelvac PRRS MLV, Boehringer Ingelheim Vetmedica) was administered intramuscularly in the neck according to the manufacturer’s instructions. The challenge strain used was Lelystad virus at a dose of 106.0 TCID50/pig. Escherichia coli LPS (O111:B4) was given intratracheally at a dose of 20 mg/kg body weight. Respiratory signs (tachypnoea, abdominal breathing, dyspnoea) were recorded every 2 hours until 12 hours after LPS administration. Scores were given for these 3 parameters. Respiration rates of 45 were scored as 0, rates between 46 and 59 as 1 and rates of 60 as 2. Abdominal breathing and dyspnoea were scored as 0 (absent) or 1 (present). Scores were added up and a mean of the cumulative respiratory scores was calculated. Results and Discussion The mean respiratory scores upon LPS exposure are shown in Table 1. Non-vaccinated non-challenged Pigs (groups A3 and B3) experienced none or very slight respiratory signs upon LPS exposure. In non-vaccinated challenged Pigs (groups A2 and B2), on the other hand, LPS induced clear respiratory signs. Clinical signs consisted of tachypnoea, abdominal breathing and dyspnoea and were present in 88% and 80% of the Pigs, showing that the synergy between PRRSV and LPS was clearly present. In experiment 1, vaccinated Pigs, which were challenged intratracheally (group A1), developed clear respiratory signs upon LPS exposure. In experiment 2, vaccinated Pigs, which were challenged intranasally (group B1), experienced none or very slight respiratory signs. The differences in respiratory scores between Pigs of groups A1 and A2 were not significant (P=0.56-0.96). The difference between Pigs of groups B1 and B2, on the other hand, was significant (P=0.08). The present results suggest that the dual inoculation method can be used to test the clinical efficacy of modified live PRRSV vaccines. The reason why vaccinated Pigs developed clear respiratory signs upon LPS exposure in experiment 1, but not in experiment 2, may be the intratracheal inoculation of the challenge virus. It is possible that after intranasal inoculation the replication of challenge virus in lungs is lower than after intratracheal inoculation. A definite conclusion will be made once the degree of virus replication in the different groups will be known. These virological examinations are currently performed. References 1. Labarque G, et al. 2000. Vet Res 31:97. 2. Labarque G, et al. 2002. Vet Microbiol cond. accepted. 3. van Woensel PAM, et al. 1998. Vet Rec 142: 510-512.
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dual infections of Feeder Pigs with porcine reproductive and respiratory syndrome virus followed by porcine respiratory coronavirus or swine influenza virus a clinical and virological study
Veterinary Microbiology, 1996Co-Authors: Kristien Van Reeth, Hans Nauwynck, Maurice PensaertAbstract:Abstract Dual infections of Pigs with porcine reproductive and respiratory syndrome virus (PRRSV) followed by a second common respiratory virus, either porcine respiratory coronavirus (PRCV) or swine influenza virus (SIV), were studied. The aim was to determine if dual infections, as compared to single virus infections, result in enhanced clinical manifestations. It was also examined if PRRSV replication affects replication of PRCV or SIV in the respiratory tract. Groups of conventional 10 week old Pigs were inoculated with PRRSV-only (3 Pigs), PRCV-only (4 Pigs) or SIV-only (4 Pigs). Dual inoculations with PRRSV-PRCV (4 Pigs) and PRRSV-SIV (3 groups of 4, 4 and 5 Pigs) were performed at a 3 day interval. A group of uninoculated control Pigs (8 Pigs) was included. The infection with PRRSV-only induced a transient fever (40.2°C) at 2 DPI, but no respiratory signs. The PRCV-only infection remained subclinical. The SIV-only infection resulted in a one day fever (40.1°C) with moderate tachypnoea and dyspnoea. Mean weight gain in the virus-inoculated groups was retarded compared with the control group. The PRRSV-PRCV infection induced a 9 day lasting fever (peak 40.9°C) with tachypnoea, dyspnoea and productive coughing. The PRRSV-SIV infection resulted in fever and respiratory signs in all 3 groups. Clinical signs, however, were more pronounced in group 1 than in groups 2 and 3. Pigs of group 1 showed fever during 10 days (peak 41.4°C), tachypnoea, marked dyspnoea with abdominal breathing, and a productive cough. Pigs of groups 2 and 3 had fever for 5 and 3 days (peaks 40.6 and 40.3°C) respectively and mild respiratory disorders. Mean weight gain during 14 DPI of the 2nd virus was 5.9 kg in the PRRSV-PRCV group and 4.0, 6.8 and 6.7 kg in PRRSV-SIV groups 1, 2 and 3 respectively. Mean weight gain during the corresponding period in the PRRSV-only group was 8.6 kg. It was concluded that dual infections with viruses causes more severe disease and growth retardation than single PRRSV infection. PRCV excretion curves were similar in single and dual virus inoculated groups. Excretion of SIV was delayed by 2 days in the dual inoculated Pigs. Thus, replication of the second virus is not (PRCV) or only slightly (SIV) affected by a prior infection with PRRSV.
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prevalence of infections with enzootic respiratory and enteric viruses in Feeder Pigs entering fattening herds
Veterinary Record, 1994Co-Authors: K Van Reeth, Maurice PensaertAbstract:The prevalence of infections with H1N1- and H3N2-influenza viruses, porcine respiratory coronavirus (PRCV), transmissible gastroenteritis virus (TGEV) and porcine epidemic diarrhoea virus (PEDV) in Feeder Pigs shortly after their entry into fattening units was examined. Ten groups of Pigs with acute respiratory disease during the months September to October 1991 and seven groups of Pigs with acute diarrhoea during the months February to March 1992 were investigated. On arrival in the fattening herds, more of the Pigs were negative for antibodies against H1N1-influenza virus and against PRCV during September to October (61 and 50 per cent, respectively) than in February to March (51 and 34 per cent, respectively). There was serological evidence of a triple infection with PRCV and both influenza viruses in seven of the 17 groups; dual infections with PRCV and H1N1-influenza virus occurred in nine groups and with H1N1- and H3N2-influenza viruses in one group. Seroconversion against TGEV was not detected in any of the 17 groups, but seven of them had seroconverted to PEDV. Multiple infections with PRCV and either one or both of the influenza viruses were thus very common shortly after the introduction of Feeder Pigs into the fattening herds. There was no association between the type and/or multiplicity of these infections and respiratory disease, but infections with PEDV were clearly associated with outbreaks of diarrhoea.
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porcine respiratory coronavirus mediated interference against influenza virus replication in the respiratory tract of Feeder Pigs
American Journal of Veterinary Research, 1994Co-Authors: K Van Reeth, Maurice PensaertAbstract:Effect of prior porcine respiratory coronavirus (PRCV) infection on replication of H1N1-influenza virus in the respiratory tract of swine was studied. In an initial experiment, 3 groups of 5 Feeder Pigs were studied. Pigs of 2 groups were inoculated sequentially with PRCV, followed by H1N1-influenza virus at 2-and 3-day intervals. Pigs of the other group were inoculated with H1N1-influenza virus only. Pigs were monitored clinically and examined for nasal excretion of influenza virus. In the singly influenza virus-inoculated group, 83% of nasal swab specimens were influenza virus-positive over a period of 6 days after inoculation. In the dually virus-inoculated groups, only 27% (2-day interval) and 53% (3-day interval) of nasal swab specimens were virus-positive over the same postinoculation period. However, clinical signs of infection in these dually inoculated Pigs were more severe than those in the singly influenza virus-inoculated Pigs. There were no significant differences in antibody responses against influenza virus among the 3 groups of Pigs. In a second experiment, 2 groups of Pigs were studied. One group of Pigs was inoculated sequentially with PRCV, followed by H1N1-influenza virus 2 days later; the other group was inoculated with H1N1-influenza virus only. Pigs of both groups were serially euthanatized on postinoculation days (PID) 1, 2, 3, and 4 (after influenza virus). At necropsy, influenza virus titer and immunofluorescence in lung tissue were determined and gross lung lesions were recorded. Influenza virus titer in the dually inoculated Pigs (PID 1 and 2) was at least 100-fold reduced, compared with that in the corresponding singly inoculated Pigs, and fluorescence was either not detected (PID 1) or was scant (PID 2). Differences in influenza virus replication between Pigs of dually and singly inoculated groups became gradually less pronounced at PID 3 and 4. Lung lesions in the dually virus-inoculated Pigs were distinctly more severe than those in the corresponding singly virus-inoculated Pigs, and became progressively more pronounced as time after influenza virus inoculation progressed. These results indicate that PRCV infection may induce factors in the lungs that markedly interfere with replication and virus production during a subsequent influenza virus infection. On the other hand, clinical signs of infection and lung lesions were enhanced in the dually virus-inoculated Pigs. It is believed that early nonspecific defense mechanisms in the lungs may have a role in the host antiviral response, as well as in development of lesions.
F. Schmoll - One of the best experts on this subject based on the ideXlab platform.
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Systemic cytokine profile in Feeder Pigs suffering from natural postweaning multisystemic wasting syndrome (PMWS) as determined by semiquantitative RT-PCR and flow cytometric intracellular cytokine detection.
Veterinary immunology and immunopathology, 2020Co-Authors: Wolfgang Sipos, J. C. Duvigneau, Martin Willheim, F. Schilcher, Romana T. Hartl, G. Hofbauer, B. Exel, Peter Pietschmann, F. SchmollAbstract:Postweaning multisystemic wasting syndrome (PMWS) is an economically important disease in Pigs caused by porcine circovirus type 2 (PCV2). Development of this disease is presumably associated with an impairment of the immune system. We, therefore, investigated the systemic expression of relevant cytokines (IL-1, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p40, TNF-alpha, IFN-gamma) and IL-2Ralpha at mRNA (semiquantitative RT-PCR) and at protein level (flow cytometric intracellular cytokine detection after short-time stimulation of peripheral blood mononuclear cells) in 10 Feeder Pigs aged 14 weeks suffering from natural PMWS and in 10 clinically healthy pen-mates. Hematological examination revealed a significant (p < 0.001) relative lymphopenia in the diseased animals when compared to reference Pigs. IL-1alpha and IL-10 mRNA levels were notably increased in the affected Pigs, whereas IL-2 and IL-2Ralpha (CD25) mRNA levels tended to be down-regulated. IL-8, TNF-alpha and IFN-gamma mRNA expressions appeared to be slightly increased. Intracellular cytokine levels as measured by flow cytometry revealed an increase of IL-1beta, IL-2, and IL-6, whereas IL-12 and TNF-alpha expressions were not affected. IFN-gamma was slightly decreased in the diseased animals. In conclusion, despite the assumption, that the cellular immune response to PMWS as a virus-induced disease should be characterized by either a Th1 driven cytokine profile or a cytokine profile indicative of T cell immunosuppression, our results did not support that hypothesis. Nevertheless, data from intracellular cytokine detection suggest an even increased percentage of the remaining lymphocytes capable to produce IL-2 upon in vitro stimulation, which is in contrast to the slightly diminished IL-2 mRNA levels reflecting the in vivo situation at least at the mRNA level.
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Systemic cytokine profile in Feeder Pigs suffering from natural postweaning multisystemic wasting syndrome (PMWS) as determined by semiquantitative RT-PCR and flow cytometric intracellular cytokine detection.
Veterinary Immunology and Immunopathology, 2004Co-Authors: Wolfgang Sipos, J. C. Duvigneau, Martin Willheim, F. Schilcher, Romana T. Hartl, G. Hofbauer, B. Exel, Peter Pietschmann, F. SchmollAbstract:Postweaning multisystemic wasting syndrome (PMWS) is an economically important disease in Pigs caused by porcine circovirus type 2 (PCV2). Development of this disease is presumably associated with an impairment of the immune system. We, therefore, investigated the systemic expression of relevant cytokines (IL-1, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p40, TNF-α, IFN-γ) and IL-2Rα at mRNA (semiquantitative RT–PCR) and at protein level (flow cytometric intracellular cytokine detection after short-time stimulation of peripheral blood mononuclear cells) in 10 Feeder Pigs aged 14 weeks suffering from natural PMWS and in 10 clinically healthy pen-mates. Hematological examination revealed a significant (p
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systemic cytokine profile in Feeder Pigs suffering from natural postweaning multisystemic wasting syndrome pmws as determined by semiquantitative rt pcr and flow cytometric intracellular cytokine detection
Veterinary Immunology and Immunopathology, 2004Co-Authors: Wolfgang Sipos, J. C. Duvigneau, Martin Willheim, F. Schilcher, Romana T. Hartl, G. Hofbauer, B. Exel, Peter Pietschmann, F. SchmollAbstract:Postweaning multisystemic wasting syndrome (PMWS) is an economically important disease in Pigs caused by porcine circovirus type 2 (PCV2). Development of this disease is presumably associated with an impairment of the immune system. We, therefore, investigated the systemic expression of relevant cytokines (IL-1, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p40, TNF-α, IFN-γ) and IL-2Rα at mRNA (semiquantitative RT–PCR) and at protein level (flow cytometric intracellular cytokine detection after short-time stimulation of peripheral blood mononuclear cells) in 10 Feeder Pigs aged 14 weeks suffering from natural PMWS and in 10 clinically healthy pen-mates. Hematological examination revealed a significant (p<0.001) relative lymphopenia in the diseased animals when compared to reference Pigs. IL-1α and IL-10 mRNA levels were notably increased in the affected Pigs, whereas IL-2 and IL-2Rα (CD25) mRNA levels tended to be down-regulated. IL-8, TNF-α and IFN-γ mRNA expressions appeared to be slightly increased. Intracellular cytokine levels as measured by flow cytometry revealed an increase of IL-1β, IL-2, and IL-6, whereas IL-12 and TNF-α expressions were not affected. IFN-γ was slightly decreased in the diseased animals. In conclusion, despite the assumption, that the cellular immune response to PMWS as a virus-induced disease should be characterized by either a Th1 driven cytokine profile or a cytokine profile indicative of T cell immunosuppression, our results did not support that hypothesis. Nevertheless, data from intracellular cytokine detection suggest an even increased percentage of the remaining lymphocytes capable to produce IL-2 upon in vitro stimulation, which is in contrast to the slightly diminished IL-2 mRNA levels reflecting the in vivo situation at least at the mRNA level.
