Experimental Infection Of Goats Research Articles

Experimental infection of goats with Mycobacterium microti induces subclinical pulmonary tuberculosis and mild responses to tuberculin skin tests

Mycobacterium microti is a member of the Mycobacterium tuberculosis complex that seldom causes disease in livestock and humans. This study evaluated the effects on immunodiagnosis and the pathological findings in goats after experimental exposure by different routes and doses to M. microti. In a first experiment goats were challenged orally (PO, n = 7) or intranasally (IN, n = 7) with 104 CFU. In a second experiment, the endobronchial route was assessed, with a low dose of 102 CFU (EB-LD, n = 7) and a high dose of 105 CFU (EB-HD, n = 7) as well as the subcutaneous route (SC, n = 5). Temperature, body weight, clinical signs and immunological responses were monitored. Pathological evaluation was carried out and samples were processed for mycobacterial detection. Resultsdemonstrated the induction of a subclinical pulmonary infection in all the EB-HD challenged animals. Infection was also confirmed in one animal of the SC group, but not in the EB-LD, PO or IN groups. Two animals belonging to the EB-HD and SC groups, respectively, showed positive results to the single intradermal tuberculin test, and another two animals of the EB-HD and EB-LD groups showed doubtful (inconclusive) results, indicating that M. microti can induce mild responses to tuberculin skin testing. No positive results were observed when defined antigens absent in M. microti (ESAT-6 and CPF-10) were used.Our results indicate that animals exposed to M. microti can yield positive results to the skin tests currently performed in livestock tuberculosis eradication campaigns and reinforce the need to use specific antigens in antemortem tests to avoid interference with M. bovis/M. caprae diagnosis.

The Experimental Infection of Goats with Small Ruminant Morbillivirus Originated from Barbary Sheep.

Peste des Petits Ruminants (PPR) is a transboundary contagious disease in domestic small ruminants. Infections with the small ruminant morbillivirus (SRMV) were regularly found in wildlife, with unknown roles in PPR epidemiology. In order to access infection dynamics and virulence, we infected German Edelziege goats intranasally with a SRMV isolate that originated from Barbary sheep from an outbreak in the United Arab Emirates. Six goats were infected with cell culture-isolated SRMV, and two goats were kept in contact. Goats were daily monitored, and clinical score was recorded. EDTA blood, nasal, conjunctival and rectal swab samples were collected for the detection of SRMV genome load and serum for serological analysis. Short incubation period in infected (4 to 5 dpi) as well as in contact goats (9 dpi) was followed by typical clinical signs related to PPR. The highest viral load was detectable in conjunctival and nasal swab samples with RT-qPCR and rapid pen-side test. Specific antibodies were detected at 7 dpi in infected and 14 dpi in contact goats. In general, high virulence and easy transmission of the virus originated from wildlife in domestic goats was observed. The virus isolate belongs to Asian lineage IV, genetically related to Chinese and Mongolian strains.

Putative Novel Atypical BTV Serotype '36' Identified in Small Ruminants in Switzerland.

We identified a putative novel atypical BTV serotype ‘36’ in Swiss goat flocks. In the initial flock clinical signs consisting of multifocal purulent dermatitis, facial oedema and fever were observed. Following BTV detection by RT-qPCR, serotyping identified BTV-25 and also a putative novel BTV serotype in several of the affected goats. We successfully propagated the so-called “BTV-36-CH2019” strain in cell culture, developed a specific RT-qPCR targeting Segment 2, and generated the full genome by high-throughput sequencing. Furthermore, we experimentally infected goats with BTV-36-CH2019. Regularly, EDTA blood, serum and diverse swab samples were collected. Throughout the experiment, neither fever nor clinical disease was observed in any of the inoculated goats. Four goats developed BTV viremia, whereas one inoculated goat and the two contact animals remained negative. No viral RNA was detected in the swab samples collected from nose, mouth, eye, and rectum, and thus the experimental infection of goats using this novel BTV serotype delivered no indications for any clinical symptoms or vector-free virus transmission pathways. The subclinical infection of the four goats is in accordance with the reports for other atypical BTVs. However, the clinical signs of the initial goat flock did most likely not result from infection with the novel BTV-36-CH0219.

Tulathromycin treatment does not affect bacterial dissemination or clearance of Brucella melitensis 16M following experimental infection of goats.

Brucellosis in sheep and goats, a zoonotic disease primarily associated with Brucella melitensis infections, causes significant economic losses and public health concerns worldwide. Although control measures are effective, economic limitations and nomadic lifestyles may limit vaccination coverage, and test and removal policies may not be feasible. In this study, we evaluated the effects of therapy with a long acting antimicrobial tulathromycin on the pathogenesis of brucellosis. Thirty-five goats were randomly assigned for experimental infection with B. melitensis strain 16M while open or during mid-gestation. Approximately half of the animals in each group were then treated with tulathromycin and subsequently assessed for the development of humoral responses to infection, clinical presentation, and bacterial dissemination and colonization. All animals, regardless of treatment group were successfully challenged with B. melitensis 16M demonstrated by bacterial recovery from conjunctival swabs and development of positive antibody titers. In goats infected while open, no animals aborted and Brucella was recovered from only one animal in tulathromycin-treated and one animal from the untreated group. Tulathromycin treatment of pregnant goats did not prevent abortion nor did it reduce bacterial dissemination, colonization, or shedding. Our data suggests that treatment of goats in mid-gestation with tulathromycin at the labeled dose does not influence disease pathogenesis or tissue colonization after experimental B. melitensis challenge.

Peste des petits ruminants pathogenesis on experimental infected goats by the Moroccan 2015 isolate

BackgroundPeste des petits ruminants (PPR) is a viral disease of major economic importance on small ruminants. Goats are usually known to be more susceptible to the disease. Infection chronology, virus circulation, and the disease early detection need to be better understood. This study evaluates the tissue tropism and pathogenesis of PPR following experimental infection of goats using a lineage IV virus, the most dominant in the world originated from Asia. PPRV infection was experimentally induced in 4 six-month-old goats by intra-nasal and intravenous route of cell virus suspension and from infectious mashed tissue. The clinical signs were observed and goats were euthanized at predetermined clinical score level for post-mortem examinations and PPRV detection by RT-PCR. Clinical signs of infection were present, pyrexia, serous-mucopurulent nasal discharges, coughing, diarrhea and asthenia, for both cell virus suspension and infectious mashed tissue. PPRV genome was highly detected in swabs and tissues with clinical signs dominated by pulmonary attack and digestive symptoms secondary.ResultsResults of this study indicates that PPRV is an invasive infection in animals that in a short period, less than 10 days, invade all vital organs. On live animals, early diagnostic may be easily done on lacrimal and rectal swabs.ConclusionThe experimental PPRV-infection model using the cell virus suspension is suitable for vaccine evaluation as a standard model.

Bluetongue virus serotype 27: Experimental infection of goats, sheep and cattle with three BTV-27 variants reveal atypical characteristics and likely direct contact transmission BTV-27 between goats.

Bluetongue virus (BTV) hitherto consisted of 26 recognized serotypes, of which all except BTV-26 are primarily transmitted by certain species of Culicoides biting midges. Three variants of an additional 27th bluetongue virus serotype (BTV-27v01-v03) were recently detected in asymptomatic goats in Corsica, France, 2014-2015. Molecular characterization revealed genetic differences between the three variants. Therefore, invivo characteristics were investigated by experimental infection of a total of 15 goats, 11 sheep and 4 cattle with any one of the three variants in separated animal trials. In goat trials, BTV-naïve animals of the same species were kept in a facility where direct contact was unhindered. Of the 15 inoculated goats, 13 and 14 animals were found positive for BTV-RNA and antibodies (Ab), respectively, until the end of the experiments. Surprisingly, BTV-Ab levels as measured with ELISA and neutralization test (SNT) were remarkably low in all seropositive goats. Virus isolation from whole-blood was possible at the peak of viremia until 49dpi. Moreover, detection of BTV-27v02-RNA and Ab in one contact goat indicated that-similar to BTV-26-at least one of three BTV-27 variants may be transmitted by contact between goats. In the field, BTV-27 RNA can be detected up to 6months in the whole-blood of BTV-27-infected Corsican goats. In contrast, BTV RNA was not detected in the blood of cattle or sheep. In addition, BTV-27 Abs were not detected in cattle and only a transient increase in Ab levels was observed in some sheep. None of the 30 animals showed obvious BT-like clinical signs. In summary, the phenotypes observed for BTV-27v01-v03 phenotypes correspond to a mixture of characteristics known for BTV-25 and 26.

Experimental Infection of Goats with a Newly Isolated Strain of Akabane Virus that Causes Encephalomyelitis

In 2010, there was a large-scale outbreak of bovine encephalomyelitis in Korea, and 15 new strains of Akabane virus (AKAV) were isolated. To identify the pathogenicity of one of these strains, we infected adult goats with AKAV-7 via different routes. Twenty-five female goats were used in this study and were divided into five groups: intracerebral (IC) and intrasubarachnoid (IS) viral inoculation (n=8 each), intravenous (IV) inoculation (n=4), and vaccinated before IV inoculation (n=4), in addition to a negative control animal. All animals inoculated with AKAV-7 had AKAV-neutralizing antibodies at 6-8days post infection (dpi). During the experimental period, infected animals showed no clinical signs. In the IC group, 5/8 goats had non-suppurative encephalomyelitis affecting the cerebrum. Virus S RNA segments were detected in nearly all areas of the brain. In the IS group, 3/8 goats had encephalomyelitis affecting the cerebrum, cerebellum and spinal cord. At 7 and 21dpi, virus S RNA segments were found mostly in the spinal cord, especially around the area of injection (L5-L6). Antibody titres in the serum of the vaccinated group had an early onset and slightly increased titre compared with the IV group. Histopathologically, there were no obvious lesions in the central nervous tissues in the vaccinated group, while one of four goats in the IV group showed encephalomyelitis in the parietal lobe of the cerebrum. The newly isolated AKAV-7 can cause encephalomyelitis in goats after experimental injection. The attenuated AKAV vaccine currently used in Korea may provide partial protective immunity against AKAV-7 infection, but the real effect of the vaccine requires further investigation in goats.

Pathogenicity and horizontal transmission studies of caprine parainfluenza virus type 3 JS2013 strain in goats

Parainfluenza virus type 3 (PIV3) is one of the most important viral respiratory pathogens for humans and for many animals, but goat infection has been rarely reported. In 2014, one novel PIV3 strain was first isolated from goats suffered respiratory diseases in Jiangsu and Anhui provinces of eastern China and named as caprine PIV3 (CPIV3) JS2013. In order to systematically evaluate the pathogenicity and horizontal transmission ability of this new virus, experimental infection of goats with the CPIV3 strain was done. The virus-inoculated goats (challenge control (CC) group) displayed coughing and nasal discharges from 3days post infection (dpi) and lasted for about 2 weeks. Two goats in group CC showed fever between 7 and 12dpi. As detected by a TaqMan real time quantitative RT-PCR (qRT-PCR), viremia was detected during 3–11dpi, peaked at 6dpi; and virus shedding from nasal discharge and faeces were confirmed during 3–21dpi and 4–21dpi, respectively. Virus-specific HI antibodies and neutralizing antibodies (NAs) became positive since 7dpi and 14dpi; peaked at 14dpi and 28dpi, respectively; and lasted at least 70days. Pathological lesions were mainly found on the lungs and tracheas. In addition, viruses were also detected in part of the tracheal secretion and lung samples, and the viral load in tracheal secretion was higher than that in lungs. Goats in horizontal infected group (hCC, kept in different cages in the same house with CC group) showed to be horizontally infected, with slightly milder clinical signs and pathological changes; and slightly shorter period of viremia and virus shedding. This was the first report of the detailed pathogenicity characterization of the novel CPIV3 and demonstrated its horizontal transmission ability. The results would be helpful for further studies on the preventive and control strategies for CPIV3 infections.

Characterization of tuberculous granulomas in different stages of progression and associated tertiary lymphoid tissue in goats experimentally infected with Mycobacterium avium subsp. hominissuis.

Oral infection of goats with Mycobacterium avium subsp. hominissuis (MAH) resulted in a large variety of granulomas in organized gut-associated lymphatic tissues and intestinal lymph nodes. To characterize the cellular composition of granulomas, CD4(+), CD8(+), γδ, B lymphocytes and plasma, CD25(+), CD68(+), MHC-II(+), Ki67(+) and endothelial cells were labeled in consecutive frozen sections by immunohistochemistry and acid fast bacilli (AFB) by Kinyoun stain. Granulomas with extensive necrosis, little mineralization and variable numbers of AFB surrounded by many CD4(+) T cells, but only few epitheloid macrophages were observed in severely sick goats at 2-3mpi. They were interpreted as exuberant immune reaction. Organized granulomas with very few AFB were seen in clinically healthy goats at 13mpi. The necrotic cores were surrounded by a zone of granulomatous infiltrate with many epitheloid macrophages and few lymphocytes. This zone was initially wide and highly vascularized and became progressively smaller. It was enclosed by an increasing layer of connective tissue. All organized granulomas were surrounded by compartimentalized tertiary lymphoid tissue. The granulomas in experimental infection of goats with MAH reflect the heterogeneity of lesions seen in mycobacterial infections of humans and ruminants and are therefore valuable for comparative research.

Stability of a Tick-Borne Flavivirus in Milk.

The tick-borne flaviviruses (TBFV) occur worldwide and the tick-borne encephalitis virus (TBEV) members of the group often cause severe, debilitating neurological disease in humans. Although the primary route of infection is through the bite of an infected tick, alimentary infection through the consumption of TBEV-contaminated dairy products is also well-documented and is responsible for some disease in endemic areas. Experimental infection of goats, cattle, and sheep with TBEV shows that the virus can be excreted in the milk of infected animals. Additionally, the virus remains infectious after exposure to low pH levels, similar to those found in the stomach. To evaluate the survival of virus in milk, we studied the stability of the BSL-2 TBFV, Langat virus, in unpasteurized goat milk over time and after different thermal treatments. Virus was stable in milk maintained under refrigeration conditions; however, there was a marked reduction in virus titer after incubation at room temperature. High temperature, short time pasteurization protocols completely inactivated the virus. Interestingly, simulation of a typical thermal regime utilized for cheese did not completely inactivate the virus in milk. These findings stress the importance of proper milk handling and pasteurization processes in areas endemic for TBEV.

Role of the PRNP S127 allele in experimental infection of goats with classical caprine scrapie.

Classical scrapie is a transmissible spongiform encephalopathy affecting domestic goats and sheep and associated with accumulation of a misfolded isoform (PrPSc) of the PRNP gene product. Multiple PRNP polymorphisms have been reported in goats.1, 2 Experimental scrapie inoculation studies revealed that PRNP polymorphisms at codons 146, 154, 211, and 222 can provide resistance or a prolonged incubation period.3-5 A recent study identified the association between a polymorphism at codon 127 (G127S) and reduced probability of developing clinical signs of scrapie in goats with PrPSc detectable in the brain.6 In that study, the length of the incubation period (time from infection to clinical signs) was not known. The aim of this study was to identify whether goats with the heterozygous (G/S127) genotype have an extended incubation period compared with goats homozygous for G127 (G/G127) following classical caprine scrapie inoculation. Intracerebral inoculation was performed with brain homogenates from two natural field cases of scrapie, one G/G127 and one G/S127, as described (Table S1). Data were combined from previous reports4, 5 to achieve efficient animal use. Because the previous report6 suggested a prolonged incubation time for G/S127 goats, a one-tailed nonparametric exact test (see Appendix S1) was used to assess the recipient genotype hypothesis that G/S127 goats have longer incubation times than do G/G127 goats when intracerebrally inoculated with classical caprine scrapie from G/G127 genotype source material. In the absence of preliminary data, two-tailed nonparametric exact tests were used for all other analyses. All inoculated goats developed clinical signs of scrapie (Table S1), with disease confirmed by the detection of PrPSc in brainstem at the obex and most lymphoid tissues by immunohistochemistry8 (Fig. S1). A significant (P = 0.019) increase in incubation time was observed in G/S127 goats following inoculation with the G/G127 caprine brain homogenate (range: 647–1333 days). No significant difference in incubation time was observed for G/G127 versus G/S127 inoculum in G/G127 goats (P = 0.30). Incubation times in control G/G127 goats inoculated with the G/G127 brain homogenate (range: 261–332 days) were significantly shorter than observed in prior work (both P < 0.054, 5). Our findings include the first reported classical scrapie incubation times for G/S127 goats, confirming that S127 is not protective in goats.6, 7 These data suggest that eradication programs need to include extended traceback periods and longer post-exposure monitoring times for infected herds containing G/S127 goats. This work was supported by USDA-ARS Grant 2090-32000-030-00D. We thank Linda Hamburg, Thomas Truscott, Lori Fuller, Dongyue Zhuang, and Emma Karel for technical assistance. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Experimental infection of goats with Mycobacterium avium subsp. hominissuis: Pathomorphological investigations

Experimental infection of goats with Mycobacterium avium subsp. hominissuis: Pathomorphological investigations

Phylogeny of BTV in Morocco: determination of new reassortants

Phylogeny of BTV in Morocco: determination of new reassortants

Experimental Infection of Goats with Tick-Borne Encephalitis Virus and the Possibilities to Prevent Virus Transmission by Raw Goat Milk

Objectives: The aim of this work was to study the tick-borne encephalitis virus (TBEV) infection of goats and the possibilities to prevent human milk-borne infections either by immunizing animals or the heat treatment of milk. Methods: An experiment was conducted with 20 milking goats. Ten goats (half of them immunized) were challenged with live TBEV and 10 were left uninfected. Clinical signs and body temperatures of the animals were recorded and milk samples were collected daily. The presence of viral RNA and infectious virions in milk were detected by RT-PCR and intracerebral inoculation of suckling mice, respectively. Milk samples containing infectious virions were subjected to various heat treatment conditions and retested afterwards to assess the effect on infectivity. Results: The infected goats did not show any clinical signs or fever compared to uninfected ones. Infectious virions were detected for 8–19 days from the milk samples (genome for 3–18 days by PCR) of infected goats. Immunized goats did not shed the virus. After heat treatment of the milk, the inoculated mice survived. Conclusions: Goats shed the virus with their milk without showing any symptoms. Human milk-borne infections can be avoided both by immunizing goats and boiling/pasteurizing infected milk.

Experimental Infection of Goats with Parainfluenza Virus Type 3

Summary Eleven goats were inoculated intranasally and intratracheally with a bovine (T 1) strain of Parainfluenza type 3 (PI 3) virus and 10 of them were killed serially 2 to 16 days later. No clinical signs of respiratory disease were observed. The virus was recovered intermittently from the nasal passage of all the goats up to 6 days and from the turbinate and tracheal mucosae, tonsil, retropharyngeal and bronchial lymph nodes and lungs of goats killed 2 and 5 days after inoculation. Significant serum neutralization (SN) and haemagglutination-inhibiting (HI) antibodies were developed in the goats killed 12 and 16 days after inoculation. Histological changes indicative of PI 3 virus infection were observed in the upper respiratory passage and lungs of the goats killed 2 and 5 days after exposure. No cytoplasmic inclusion bodies were detected in the inflammatory cells or in the affected bronchial and alveolar epithelial tissues. Zusammenfassung Experimentelle Infektion von Ziegen mit Parainfluenza-3-Virus Elf Ziegen wurden intranasal und intratracheal mit bovinem Parainfluen-za-3-Virus (Stamm T 1) infiziert. Es traten keine klinisch sichtbaren Symptome ciner respiratorischen Erkrankung auf. Das Virus wurde bis zum 6. Tag nach der Infektion von allen Ziegen aus Nasensekret, sowie von den 2 und 5 Tage nach der Infektion getöteten Tieren aus Schleimhaut der Turbinalien und der Trachea, aus Tonsillen, Retropharyngeal- und Bronchiallymphknoten, sowie aus der Lunge reisoliert. Bei den am 12. und 16. Tag nach der Infektion getöteten Ziegen waren die Titer neutralisierender und hämagglutinationshemmender Antikörper signifikant angestiegen. Histologische, auf eine Parainfluenza-3-Virusinfektion hindeutende Veränderungen fanden sich bei den am 2. und 5. Tag nach der Infektion getöteten Tieren. Einschlußkörperchen sind nicht gefunden worden. Résumé Infection expérimentale de chèvres avec un virus Parainfluenza-3 11 chèvres ont été infectées par voie intranasale et intratrachéale avec un virus Parainfluenza-3 bovin (Souche T 1). Il n'y a pas eu de symptômes cliniques visibles d'une affection respiratoire. Le virus a été réisolé dans les sécrétions nasales chez toutes les chèvres jusqu'au 6ème jour après l'infection. On a également réisolé le virus chez des animaux sacrifiés du 2ème au 5ème jour après l'infection à partir de la muqueuse des voies nasales, de la trachée, à partir des amygdales, des ganglions retropharyngés et bronchiques ainsi que des poumons. Le titre des anticorps neutralisant et inhibant l'hémagglutination fut significativement augmenté chez les chèvres sacrifiée le 12e et le 16e jour après l'infection. On n'a pas trouvé histologiquement d'inclusions chez les animaux sacrifiés au 2e et 5e jour après l'infection. Resumen Infección experimental de cabras con el virus de la parainfluenza-3 Se infectaron once cabras por las vías intranasal e intratraqueal con el virus bovino de la parainfluenza-3 (estirpe T 1). No se presentaron síntomas clínicamente apreciables de una enfermedad respiratoria. El virus se reaisló hasta el día 6° después de la infección en todas las cabras de la secreción nasal, así como en los animales matados 2 y 5 días tras la infección de la mucosa de los cornetes nasales y de la tráquea, de las tonsilas, ganglios linfáticos retrofaríngeos y bronquiales, a igual que del pulmón. En las cabras matadas el día 12° y 16° después de la infección habían aumentado significantemente los títulos de los anticuerpos neutralizantes e inhibidores de la hemoaglutinación. Modificaciones histopatológicas, que indicaban hacia una infección viral parainfluenza-3, se hallaron en los animales matados los días 2° y 5° tras la infección. No se ubicaron corpúsculos de inclusión.

Experimental Infection of Goats with an Unusual Strain of Mycoplasma mycoides subsp. capri Isolated in Jordan

Goats were infected experimentally with a mycoplasma (the "Irbid" strain) isolated previously from a goat with contagious agalactia in northern Jordan. The strain was unusual in that, although it had been identified by molecular methods as Mycoplasma mycoides subsp. mycoides LC/Mycoplasma mycoides subsp. capri, it showed no inhibition of growth by any of the hyperimmune rabbit antisera conventionally used to speciate members of the Mycoplasma mycoides cluster. Animals were infected either intratracheally or by aerosol and placed "in-contact" with other goats. After 2 weeks, those infected intratracheally became febrile, showing a nasal discharge and slight conjunctivitis, followed a week later by respiratory distress and polyarthritis; lesions seen at necropsy included coagulative necrotic pneumonia, fibrinous pleurisy with pleural exudate, and inflammatory exudates, necrosis and fibrosis in the joints. Animals infected by aerosol showed much milder clinical signs, including nasal discharge and occasional swollen joints. In the "in-contact" goats, seroconversion was first seen after 7 weeks, accompanied by coughing and laboured respiration; lesions in this group consisted of fibrinous pneumonia with focal areas of necrosis and abundant pleural exudate.

Toggenburg Orbivirus, a new bluetongue virus: Initial detection, first observations in field and experimental infection of goats and sheep

A novel bluetongue virus termed “Toggenburg Orbivirus” (TOV) was detected in two Swiss goat flocks. This orbivirus was characterized by sequencing of 7 of its 10 viral genome segments. The sequencing data revealed that this virus is likely to represent a new serotype of bluetongue virus [Hofmann, M.A., Renzullo, S., Mader, M., Chaignat, V., Worwa, G., Thuer, B., 2008b. Genetic characterization of Toggenburg Orbivirus (TOV) as a tentative 25th serotype of bluetongue virus, detected in goats from Switzerland. Emerg. Infect. Dis. 14, 1855–1861]. In the field, no clinical signs were observed in TOV-infected adult goats; however, several stillborn and weak born kids were reported. Although born during a period of extremely low vector activity, one of these kids was found to be antibody and viral genome positive and died 3.5 weeks postpartum. Experimental infection of goats and sheep, using TOV-positive field blood samples, was performed to assess the pathogenicity of this virus. Goats did not show any clinical or pathological signs, whereas in sheep mild bluetongue-like clinical signs were observed. Necropsy of sheep demonstrated bluetongue-typical hemorrhages in the wall of the pulmonary artery. Viral RNA was detected in organs, e.g. spleen, palatine tonsils, lung and several lymph nodes of three experimentally infected animals. Unlike other bluetongue virus serotypes, it was not possible to propagate the virus, either from naturally or experimentally infected animals in any of the tested mammalian or insect cell lines or in embryonated chicken eggs. In small ruminants, TOV leads to mild bluetongue-like symptoms. Further investigations about prevalence of this virus are needed to increase the knowledge on its epidemiology.

Experimental infection of goats at different stages of pregnancy with caprine herpesvirus 1

Three goats from a group of five caprine herpesvirus 1 (CpHV.1) seronegative pregnant goats were inoculated intranasally with a virulent BA.1 strain of CpHV.1. Goat n.1 was infected on day 45 of pregnancy, goat n.2 on day 92 and goat n.3 on day 127. Each of the three goats produced a single foetus 10–60 days after infection. Foetus n.1 was never found and so it could not be examined for virological findings. Goat n.2 delivered at term of gestation and CpHV.1 was detected by PCR and isolated from most of the foetal organs. Foetus n.3 was partially autolysed and the virus was only detected by PCR but not isolated from foetal organs. The results confirm the damaging effect of CpHV.1 infection on pregnancy, the difficulty in diagnosing the CpHV.1 induced abortion, and the importance developing appropriate prophylactic programmes.

Humoral immune responses following experimental infection of goats with Mycoplasma capricolum subsp. capripneumoniae

Goats housed in microbiologically secure facilities were experimentally endobronchially infected with Mycoplasma capricolum subsp. capripneumoniae (Mccp), causal agent of contagious caprine pleuropneumonia (CCPP). The animals were monitored over an 8-week period post-infection (p.i.). Elevated temperatures were observed 2–7 days p.i., reaching a maximum of 41.5°C in one animal (1884). By 8 weeks p.i. the infection was successfully cleared, with no Mccp being recovered from the lungs, serum or nasal passages. Mccp was not isolated from serum throughout the experiment, either directly by culture or indirectly via polymerase chain reaction (PCR). Humoral immune responses against Mccp capsular polysaccharide (CPS) were generally poor when measured by ELISA. CPS antigen was present in the serum of all infected animals early in the infection (day 14 p.i.), although in one animal (1855) CPS antigen persisted throughout. This was the only animal to exhibit a serious cough (day 5–19 p.i.). Successful diagnosis of CCPP was achieved using two different types of latex agglutination test (CPS antibody and CPS antigen detection test), immunoblotting and a blocking ELISA, although the latter lacked sensitivity until later in the infection (35–40 days p.i.). Only a single animal (1855) was detected positive using the current complement fixation test (CFT). Strong immune responses to protein antigens were detected by IgG and IgM immunoblotting from the first time point at day 14 p.i. IgM immunodominant bands of 220, 85, 62 and 40 kDa were observed in the 3 infected animals and from CFT-positive CCPP field sera. Band intensity gradually diminished throughout the experiment. IgG immunodominant bands of 108, 70, 62, 44, 40 and 23 kDa were shared between experimentally-infected and field sera, with band intensity either remaining unchanged or increasing from day 14 p.i. These bands were not present using pre-infection sera. Of the diagnostic tests used, only the CPS antibody detection latex agglutination test and IgG immunoblotting gave positive diagnoses throughout the entire period post-infection (days 14–53 p.i.).

Changes in liveweight gain and blood constituents in experimental infection of goats with a goat-derived compared with a sheep-derived strain of Haemonchus contortus

Two groups of goats were experimentally infected with two different strains of Haemonchus contortus and compared with the controls. Group A animals were infected with a goat-derived strain (GDS) while Group B animals were infected with a sheep-derived strain (SDS). Changes in the liveweights and some blood constituents between the two infected groups were compared. The pathogenic effects of the GDS larvae were generally more serious when compared with those of the SDS larvae.