Clinical Signs Of Respiratory Disease Research Articles

Comparative efficacy of tulathromycin versus combination of florfenicole & oxytetracycline in the treatment of undifferentiated respiratory diseases in feedlot calve

Respiratory disease is one of the most important diseases in sheep and cattle and economic losses due to disease are so important for food animal producing country. Tulathromycin (TUL) is a semi-synthetic, long acting Antibiotic which belongs to the macrolide group. It uses as an antibiotic in the treatment of respiratory diseases in domestic animals. In this study 200 calves that exhibiting clinical signs of respiratory disease with undifferentiated etiology selected & divided in to two groups. Group 1 treated with single injection of TUL 2.5 mg/kg BW SC and Group 2 treated with combination of oxytetracycline(OTC) 20 mg/kg BW IM & florfenicole (FFC) 40 mg/kg BW SC. Treated animals were examined 5 days after injection. In the first group (TUL) 89 calves showed sings of cure 5 days later after first injection. 11 calve needed further treatment in which 5 calve cured and 6 calve died. In the second group (OTC & FFC) 84 calves showed sings of cure 5 days later after single injection. 16 calves needed further treatment, of which 7 calves cured and 9 calves died. The results of this study indicates that usage of TUL is more effective than combination of FFC & OTC in treatment of respiratory disease with undifferentiated etiology and efficacy increased & mortality rate decreased considerably.

Relationship between the Amounts of Antibodies to Actinobacillus pleuropneumoniae Serotype 2 Detected in Blood Serum and in Fluids Collected from Muscles of Pigs

An indirect ELISA method, previously used to detect antibodies to Actinobacillus pleuropneumoniae serotype 2 in serum of pigs, was further developed aiming to measure antibodies to the microbe in muscle fluids. Serum and muscle fluid were collected from Specific Pathogen Free (SPF) pigs as well as from SPF pigs challenged with A. pleuropneumoniae which were either treated with effective antibiotics or left as infected controls. The antibody responses measured in serum correlated well to the clinical signs of respiratory disease observed and to pathological lesions found at necropsy performed 17 days post-infection. The amounts of antibodies monitored in serum and in muscle fluid collected from the diaphragm and the thigh, respectively, were compared. Higher concentrations of antibodies were assessed in serum than in diaphragm fluid, which in turn contained more antibodies per ml than fluid collected from the thigh. The amount of antibodies to A. pleuropneumoniae measured in fluid from the diaphragm diluted 1/50 correlated well with the quantity measured in serum diluted 1/1000 (r2 = 0.87; P < 0.001). When validated by using serum antibody responses as a standard, the specificity of the ELISA employed in fluid from the diaphragm was found to be 100 %. The sensitivity was determined to be 88 % when calculated on seropositive pigs (A450 = 0.3 in serum diluted 1/1000). That figure increased to 97 % if calculated on pigs expressing pronounced amounts of serum antibodies (A450 0.5).

Lavado traqueobrônquico auxiliado por endoscópio rígido ou por tubo endotraqueal em cães

Com o objetivo de se avaliarem os resultados do uso de endoscopia rígida e da técnica por tubo endotraqueal de colheita de líquido traqueobrônquico, foram utilizados 28 cães, errantes ou domiciliados, distribuídos em dois grupos. Nos cães do grupo 1, aplicou-se a técnica de lavado traqueobrônquico em 14 cães, sendo sete sadios e sete com sinais clínicos respiratórios. Nos do grupo 2, utilizou-se a mesma técnica, entretanto com endoscopia rígida, em sete cães sadios e em sete cães com sinais clínicos de doença respiratória. Os dados evidenciaram que o procedimento utilizando-se endoscópio rígido resultou em menor volume de solução infundida e em maior porcentagem de solução recuperada. Não houve diferença significativa quanto ao tempo de duração da execução da técnica. A contagem bacteriana foi mais alta nas amostras coletadas por endoscópio rígido, porém não houve diferença significativa na contagem de células nucleadas totais. Portanto, o uso da endoscopia rígida para colheita de líquido traqueobrônquico mostrou-se mais vantajosa do que a técnica convencional utilizando-se o tubo endotraqueal, pois fornece imagens das vias aéreas e permite acompanhamento visual da lavagem.

Associations between pathogens in healthy pigs and pigs with pneumonia

The aim of this study was to evaluate the associations between different pathogens in the development of pneumonia and bronchopneumonia in pigs. Samples of bronchoalveolar lavage fluid from 100 pigs...

Disease Association and Clinical Assessment of Feline Pericardial Effusion

Records were reviewed from 83 cases to determine the main causes and clinical significance of feline pericardial effusion. The most common causes included hypertrophic cardiomyopathy with congestive heart failure, neoplasia, and systemic infection. Most cases had concurrent or secondary pleural effusion or pulmonary edema, with clinical signs of respiratory disease. However, several cases appeared to be affected solely by pericardial effusion rather than pulmonary pathology. Feline pericardial effusion remains an infrequent diagnosis, but its clinical relevance and association with severe cardiac and extracardiac disease warrant diagnostic evaluation.

Treatment of pneumonia in pigs with long-acting injectable tylosin

A blinded, randomised clinical trial was carried out in Brittany, France on three commercial pig farms with a history of pneumonia. Pigs with clinical signs of respiratory disease were randomly...

Detection of respiratory herpesviruses in foals and adult horses determined by nested multiplex PCR

A nested multiplex PCR was developed as a rapid (<12 h), sensitive test for the simultaneous identification of equine herpesviruses (EHV1, EHV4, EHV2 and EHV5) in clinical samples from horses. Peripheral blood and nasal swab (NS) samples from 205 weanling Thoroughbred foals on 6 different studs over 3 consecutive seasons and from 92 adult horses without clinical signs of respiratory disease were examined using direct multiplex PCR of clinical samples (direct PCR) and conventional cell culture with differentiation of EHV in cell cultures by multiplex PCR. Multiplex PCR proved a sensitive and specific technique for the detection of EHV in cell culture and clinical samples. The technique described appeared equally sensitive as one using a single set of primers for individual EHV but reduced labour and reagent costs. Cell cultures showing cytopathic effect (CPE) were always positive for EHV on PCR. EHV were also detected by multiplex PCR in 11 samples which failed to show CPE. By a combination of multiplex PCR and cell culture or direct multiplex PCR, the presence of up to three EHV in the same sample was detected. Overall, EHV5 was detected by direct multiplex PCR of peripheral blood mononuclear cells (PBMC) and/or NS samples from 78% of foals and 47% of adult horses. Repeated sampling or cell culture in combination with multiplex PCR and with the incorporation of IL-2 in culture medium increased the sensitivity for detection of EHV in PBMC and demonstrated that EHV5 DNA could be identified in PBMC from 89% of foals and 100% of adult horses. EHV2 was identified from approximately 30% of foals, but was more frequently identified in samples from 17 foals with mild respiratory disease and was isolated infrequently from adult horses. EHV1 and EHV4 were identified uncommonly in any population in the current study.

Efficacy of tulathromycin in the treatment of respiratory disease in pigs caused by Actinobacillus pleuropneumoniae

The efficacy of a single dose of tulathromycin, a novel triamilide antimicrobial of the macrolide class, given at 2·5 mg/kg or 5 mg/kg bodyweight, or three daily doses of ceftiofur,...

Human Metapneumovirus Infection in Adult Patients after Allogeneic Hemopoietic Stem Cell Transplantation.

The human metapneumovirus (hMPV) has been described as possible cause of respiratory disease in pediatric and adult subjects. There are not, however, data concerning the epidemiology and or the clinical impact of hMPV infection in adults receiving allogeneic hemopoietic stem cell (HSC) transplant. We report the results of a prospective study aimed to asses the incidence of hMPV infection in patients undergoing allogeneic HSC transplant. We analyzed by reverse transcription PCR assay, the presence of hMPV in nasopharingeal aspirate (NPA) collected before transplant and on day 0, +15, +30, +60, +90, +180, +360 from transplant. Detection of hMPV RNA was based on two set primers pair located in the L and N genes. Amplified hMPV RNA was sequenced for genotyping in region N.Twenty patients with a median age of 37 yrs (range 25–58), receiving allogeneic HSC for hematological disorders (AML 11 pts, ALL 5 pts, MDS 2 pts, NHL and MM 1 pt each), entered the study. Six pts received transplant from an HLA identical sibling and 14 from an unrelated donor (MUD). As preparative regimen, 15 pts had a standard myeloablative conditioning regimen, and 5 received reduced intensity conditioning with Thiotepa and Fludarabine. Acute graft-versus-host-disease prophylaxis consisted of Cyclosporine A and Methotrexate. In 6 pts receiving MUD transplant, in vivo T depletion by ATG was performed. At transplant, all patients were in good performance status and none had signs of active acute respiratory disease. Of 20 patients, four had a prior history of pulmonary infection from agents different from hMPV.Of 49 NPA samples analyzed so far, 29 (59%) resulted hMPV-positive. Sequence analysis performed in 12 patents detected a virus genotype-A. Of 12 pts in whom 3 or more NPA samples were collected, 9 (45%) resulted positive for hMPV RT-PCR, with persistence of infection for a period ranging from 14 to 84 days. No patient, however, showed clinical signs of respiratory disease. These data indicate an high prevalence and a long persistence of asymptomatic hMPV infection in adults receiving allogeneic HSC transplant.

New transtracheal bronchoalveolar lavage technique for the diagnosis of respiratory disease in sheep

A new transtracheal bronchoalveolar lavage technique for the diagnosis of respiratory disease in sheep under field conditions was tested in 76 sheep. The sheep were divided into three groups, normal...

Nicoletella semolina gen. nov., sp. nov., a New Member of Pasteurellaceae Isolated from Horses with Airway Disease

Gram-negative, nonmotile bacteria that are catalase, oxidase, and urease positive are regularly isolated from the airways of horses with clinical signs of respiratory disease. On the basis of the findings by a polyphasic approach, we propose that these strains be classified as Nicoletella semolina gen. nov, sp. nov., a new member of the family Pasteurellaceae. N. semolina reduces nitrate to nitrite but is otherwise biochemically inert; this includes the lack of an ability to ferment glucose and other sugars. Growth is fastidious, and the isolates have a distinctive colony morphology, with the colonies being dry and waxy and looking like a semolina particle that can be moved around on an agar plate without losing their shape. DNA-DNA hybridization data and multilocus phylogenetic analysis, including 16S rRNA gene (rDNA), rpoB, and infB sequencing, clearly placed N. semolina as a new genus in the family Pasteurellaceae. In all the phylogenetic trees constructed, N. semolina is on a distinct branch displaying approximately 5% 16S rDNA, approximately 16% rpoB, and approximately 20% infB sequence divergence from its nearest relative within the family Pasteurellaceae. High degrees of conservation of the 16S rDNA (99.8%), rpoB (99.6%), and infB (99.7%) sequences exist within the species, indicating that N. semolina isolates not only are phenotypically homogeneous but also are genetically homogeneous. The type strain of N. semolina is CCUG43639(T) (DSM16380(T)).

Duration of immunity of a quadrivalent vaccine against respiratory diseases caused by BHV-1, PI 3V, BVDV, and BRSV in experimentally infected calves

Several laboratory studies assessed the duration of immunity of a quadrivalent vaccine (Rispoval™4, Pfizer Animal Health) against bovine respiratory diseases (BRD) caused by bovine herpes-virus type-1 (BHV-1), parainfluenza type-3 virus (PI 3V), bovine viral-diarrhoea virus type 1 (BVDV), or bovine respiratory syncytial virus (BRSV). Calves between 7 weeks and 6 months of age were allocated to treatment and then were injected with two doses of either the vaccine or the placebo 3 weeks apart. Six to 12 months after the second injection, animals were challenged with BHV-1 ( n = 16), PI 3V ( n = 31), BVDV ( n = 16), or BRSV ( n = 20) and the course of viral infection was monitored by serological, haematological (in the BVDV study only), clinical, and virological means for ≥2 weeks. Infection induced mild clinical signs of respiratory disease and elevated rectal temperature in both vaccinated and control animals and was followed by a dramatic rise in neutralising antibodies in all treatment groups. Titres reached higher levels in vaccinated calves than in control calves after challenge with BHV-1, BVDV, or BRSV. On day 3 after PI 3V challenge, virus shedding was reduced from 3.64 log 10 TCID 50 in control animals to 2.59 log 10 TCID 50 in vaccinated animals. On days 6 and 8 after BRSV challenge, there were fewer vaccinated animals ( n = 2/10 and 0/10, respectively) shedding the virus than control animals ( n = 8/10 and 3/10, respectively). Moreover, after challenge, the mean duration of virus shedding was reduced from 3.8 days in control animals to 1 day in vaccinated animals in the BVDV study and from 3.4 days in control animals to 1.2 days in vaccinated animals in the BRSV study. The duration of immunity of ≥6 months for PI 3V, BHV-1 and BVDV, and 12 months for BRSV, after vaccination with Rispoval™4, was associated mainly with enhanced post-challenge antibody response to all four viruses and reduction of the amount or duration of virus shedding or both.

A placebo-controlled trial of two intranasal vaccines to prevent tracheobronchitis (kennel cough) in dogs entering a humane shelter

A placebo-controlled field trial was conducted to compare the effectiveness of intranasal (IN) vaccines containing Bordetella bronchiseptica and canine-parainfluenza virus, with (IN-BPA) or without (IN-BP) canine-adenovirus type 2, for prevention of kennel cough at a humane shelter. Dogs were examined on admission to the shelter and those without respiratory signs of disease were assigned daily, on a rotating basis, to receive one of three vaccines. We enrolled 972 healthy dogs. Dogs were monitored for up to 30 days post-vaccination for coughing and other clinical signs of respiratory disease. Thirty-three (10.7%; 95% confidence interval (CI): 7.2, 14.2) dogs in the IN-BP group, 36 (10.2%; 95% CI: 7.0, 13.4) dogs in the IN-BPA group, and 42 (13.5%; 95% CI: 9.7, 17.3) dogs in the IN-P group coughed spontaneously for ≥1 day within 30 days of vaccination ( P=0.37). The IN-BP and IN-BPA vaccines were 20.7 and 24.4% effective, respectively, in reducing coughing compared with a placebo vaccine. The strongest prognostic factor for coughing (regardless of vaccine group) was the number of days spent at the shelter, with each additional day increasing the risk of coughing by 3% (95% CI: 0.5, 6.3). The low incidence of coughing in the shelter during this study precluded observation of differences in vaccine effectiveness. No differences in vaccine-associated adverse events (coughing, sneezing, nasal or ocular discharge) were noted during the first 3 days post-administration or thereafter.

Some Aspects of the Stress Responses to Road Transport in Thoroughbred Horses with Special Reference to Shipping Fever

We performed two sets of experiments consisting of 36 hr and 41 hr of transportation to elucidate the road transit-induced stress response's profiles in horses with clinical signs of respiratory disease (affected horses) and horses without clinical signs of respiratory disease (unaffected horses). In both sets of experiments, affected horses showed a significantly greater increase or decrease in levels of the indices of the stress response, i.e., eosinophil count, erythrocyte sedimentation rate, levels of serum glucose, adrenocorticotropic hormone (ACTH) and 11-hydroxycorticosteroid (11-OHCS) than unaffected horses after road transportation. Compared with unaffected horses, affected horses had a different pattern of changes in indices of the stress response, suggesting that they failed to adapt to transportation.

Chronic pulmonary disease with radiographic interstitial opacity (interstitial pneumonia) in foals.

Twelve foals, age 3-9 months, examined at The Ohio State University Veterinary Teaching Hospital between 1995 and 2000 were diagnosed with chronic pulmonary disease associated with marked interstitial opacity on radiographic examination. The most characteristic features were a history of respiratory disease of 1-3 months duration, marked clinical signs of respiratory disease, failure to yield a consistent pathogen from tracheobronchial aspirates and a predominantly interstitial pattern on thoracic radiographs. We attributed these signs to chronic interstitial pneumonia. Foals were treated with broad spectrum antimicrobial and corticosteroid drugs. All 12 foals were discharged alive from hospital and, of the 10 available for follow-up, all were disease-free and performing to expectation 5 months to 5 years after discharge. We conclude that chronic interstitial pneumonia, occuring in foals, is associated with a good prognosis and that corticosteroid therapy may be useful in its treatment.

Viruses associated with outbreaks of equine respiratory disease in New Zealand

AIM: To identify viruses associated with respiratory disease in young horses in New Zealand. METHODS: Nasal swabs and blood samples were collected from 45 foals or horses from five separate outbreaks of respiratory disease that occurred in New Zealand in 1996, and from 37 yearlings at the time of the annual yearling sales in January that same year. Virus isolation from nasal swabs and peripheral blood leukocytes (PBL) was undertaken and serum samples were tested for antibodies against equine herpesviruses (EHV-1, EHV-2, EHV-4 and EHV-5), equine rhinitis-A virus (ERAV), equine rhinitis-B virus (ERBV), equine adenovirus 1 (EAdV-1), equine arteritis virus (EAV), reovirus 3 and parainfluenza virus type 3 (PIV3). RESULTS: Viruses were isolated from 24/94 (26%) nasal swab samples and from 77/80 (96%) PBL samples collected from both healthy horses and horses showing clinical signs of respiratory disease. All isolates were identified as EHV-2, EHV-4, EHV-5 or untyped EHV. Of the horses and foals tested, 59/82 (72%) were positive for EHV-1 and/or EHV-4 serum neutralising (SN) antibody on at least one sampling occasion, 52/82 (63%) for EHV-1-specific antibody tested by enzyme-linked immunosorbent assay (ELISA), 10/80 (13%) for ERAV SN antibody, 60/80 (75%) for ERBV SN antibody, and 42/80 (53%) for haemagglutination inhibition (HI) antibody to EAdV-1. None of the 64 serum samples tested were positive for antibodies to EAV, reovirus 3 or PIV3. Evidence of infection with all viruses tested was detected in both healthy horses and in horses showing clinical signs of respiratory disease. Recent EHV-2 infection was associated with the development of signs of respiratory disease among yearlings [relative risk (RR)=2.67, 95% CI=1.59-4.47, p=0.017]. CONCLUSIONS: Of the equine respiratory viruses detected in horses in New Zealand during this study, EHV-2 was most likely to be associated with respiratory disease. However, factors other than viral infection are probably important in the development of clinical signs of disease.

Equine respiratory viruses in foals in New Zealand

AIMS: To identify the respiratory viruses that are present among foals in New Zealand and to establish the age at which foals first become infected with these viruses. METHODS: Foals were recruited to the study in October/November 1995 at the age of 1 month (Group A) or in March/April 1996 at the age of 4–6 months (Groups B and C). Nasal swabs and blood samples were collected at monthly intervals. Nasal swabs and peripheral blood leucocytes (PBL) harvested from heparinised blood samples were used for virus isolation; serum harvested from whole-blood samples was used for serological testing for the presence of antibodies against equine herpesvirus (EHV)-1 or -4, equine rhinitis-A virus (ERAV), equine rhinitis-B virus (ERBV), equine adenovirus 1 (EAdV-1), equine arteritis virus (EAV), reovirus 3 and parainfluenza virus type 3 (PIV3). Twelve foals were sampled until December 1996; the remaining 19 foals were lost from the study at various times prior to this date. RESULTS: The only viruses isolated were EHV-2 and EHV-5. EHV-2 was isolated from 155/157 PBL samples collected during the period of study and from 40/172 nasal swabs collected from 18 foals. All isolations from nasal swabs, except one, were made over a period of 2–4 months from January to April (Group A), March to April (Group B) or May to July (Group C). EHV-5 was isolated from either PBL, nasal swabs, or both, from 15 foals on 32 occasions. All foals were positive for antibodies to EHV-1 or EHV-4, as tested by serum neutralisation (SN), on at least one sampling occasion and all but one were positive for EHV-1 antibodies measured by enzyme-linked immunosorbent assay (ELISA) on at least one sampling occasion. Recent EHV-1 infection was evident at least once during the period of study in 18/23 (78%) foals for which at least two samples were collected. SN antibodies to ERBV were evident in 19/23 (83%) foals on at least one sampling occasion and 15/23 foals showed evidence of seroconversion to ERBV. Antibodies to ERAV were only detected in serum samples collected from foals in Group A and probably represented maternally-derived antibodies. Haemagglutination inhibition (HI) antibody titres ≥1:10 to EAdV-1were evident in 21/23 (91%) foals on at least one sampling occasion and 16/23 foals showed serological evidence of recent EAdV-1 infection. None of the 67 serum samples tested were positive for antibodies to EAV, reovirus 3 or PIV3. There was no clear association between infection with any of the viruses isolated or tested for and the presence of overt clinical signs of respiratory disease. CONCLUSIONS: There was serological and/or virological evidence that EHV-1, EHV-2, EHV-5, EAdV-1 and ERBV infections were present among foals in New Zealand. EHV-2 infection was first detected in foals as young as 3 months of age. The isolation of EHV-2 from nasal swabs preceded serological evidence of infection with other respiratory viruses, suggesting that EHV-2 may predispose foals to other viral infections.

Prevalence of antibodies to Chlamydia pneumoniae in an Israeli population without clinical evidence of respiratory infection.

To estimate the occurrence of recent, past, and "persistent" infections with Chlamydia pneumoniae--as indicated by serology--in an Israeli population without clinical evidence of respiratory infection. Serum samples from 402 subjects (172 children and 230 adults), without known respiratory symptoms, were collected. Antibodies to C pneumoniae (IgG, IgA, and IgM) were evaluated using the microimmunofluorescence (MIF) assay. Antibody prevalence and indication of recent, past, and persistent infections were calculated and their distribution determined according to age, sex, and season. Antibodies to C pneumoniae were detected in 53 children (31%) and 171 adults (74%). Recent infection was indicated in only one of 50 children under 5 years of age, in nine of 122 older children, and in 19 of 230 adults. IgM antibodies were detected in nine children, but only in three adults. Past infection was indicated in six of 96 young children (aged 1-10 years), in 28 of 76 teenagers, and in 128 of 230 adults. Persistent infection was indicated in three young children, in six teenagers, and in 24 adults, with a significantly higher frequency (p = 0.012) in men (18 of 117) than in women (six of 113). No seasonal differences could be detected. Infection with C pneumoniae was detected serologically in children and adults without clinical signs of respiratory disease. These results should serve as a basis for studies on the role of C pneumoniae infections and their sequelae in Israel and contribute to the general understanding of asymptomatic infection with C pneumoniae.

DIFERENCIAÇÃO CLÍNICA DA BRONCOPNEUMONIA MODERADA E GRAVE EM BEZERROS

Com o objetivo de identificar os principais sinais clínicos de bezerros com broncopneumonia e definir a doença nas formas moderada e grave, foram utilizados 48 bezerros divididos em 3 grupos: 10 clinicamente sadios (G1), 18 com broncopneumonia moderada (G2) e 20 com broncopneumonia grave (G3). A classificação dos grupos sadios e doentes (broncopneumonia moderada e grave) obedeceu a critérios clínicos e foi confirmada estatisticamente por Análise de Agrupamento. Os resultados evidenciaram ausência de sinais clínicos compatíveis com doença respiratória e menor escore clínico nos bezerros clinicamente sadios (G1). Os bezerros com broncopneumonia foram identificados pela presença de diversos sinais clínicos, confirmando anormalidades pulmonares. Tosse e reflexo de tosse positivo, aumento de temperatura e freqüência cardíaca, alterações dos ruídos traqueobrônquico e broncobronquiolar e inspiração interrompida, apesar de relacionados ao diagnóstico de broncopneumonia, não diferenciaram a intensidade moderada e grave do processo. A freqüência respiratória elevada, a dispnéia mista, a submacicez/macicez, área de silêncio, a crepitação grossa e os roncos e sibilos definiram a gravidade do quadro de broncopneumonia.

Relationship between the amounts of antibodies to Actinobacillus pleuropneumoniae serotype 2 detected in blood serum and in fluids collected from muscles of pigs.

An indirect ELISA method, previously used to detect antibodies to Actinobacillus pleuropneumoniae serotype 2 in serum of pigs, was further developed aiming to measure antibodies to the microbe in muscle fluids. Serum and muscle fluid were collected from Specific Pathogen Free (SPF) pigs as well as from SPF pigs challenged with A. pleuropneumoniae which were either treated with effective antibiotics or left as infected controls. The antibody responses measured in serum correlated well to the clinical signs of respiratory disease observed and to pathological lesions found at necropsy performed 17 days post-infection. The amounts of antibodies monitored in serum and in muscle fluid collected from the diaphragm and the thigh, respectively, were compared. Higher concentrations of antibodies were assessed in serum than in diaphragm fluid, which in turn contained more antibodies per ml than fluid collected from the thigh. The amount of antibodies to A. pleuropneumoniae measured in fluid from the diaphragm diluted 1/50 correlated well with the quantity measured in serum diluted 1/1000 (r2 = 0.87; P < 0.001). When validated by using serum antibody responses as a standard, the specificity of the ELISA employed in fluid from the diaphragm was found to be 100%. The sensitivity was determined to be 88% when calculated on seropositive pigs (A450 = 0.3 in serum diluted 1/1000). That figure increased to 97% if calculated on pigs expressing pronounced amounts of serum antibodies (A450 > or = 0.5).