Case Report: A Case of Caprine Arthritis Encephalitis in Dairy Goat Farms in South Korea

One Saanen dairy goat (Capra aegagrus hircus) farm in Korea reported that some goats showed clinical signs such as arthritis, paralysis, carpal joint swelling, and even death. We monitored clinical signs and pathological lesions. In the laboratory, we confirmed caprine arthritis encephalitis virus (CAEV) infection by polymerase chain reaction (PCR). We examined all the dairy goats on the farm and found that many of them were positive. In conclusion, CAEV infection was detected in the majority of the goats in this farm, and it induced severe clinical signs impacting productivity and causing important economic shortfalls. We need to regularly investigate all dairy goat farms, and, more importantly, inspection of the quarantine stage should be required before importation. Interestingly, we found all negative results in Korean native black goats (Capra hircus linnaeus).

Initial multi-target approach shows importance of improved caprine arthritis-encephalitis virus control program in Russia for hobbyist goat farms

Background and Aim: Several reports described the detection of specific caprine arthritis-encephalitis virus (CAEV) antibodies in Russian goat populations, which indicates the circulation of CAEV in Russian goat farms. The aim of this study was to use a multi-target approach to testing with both serological tests and an in-house real-time (RT) molecular test to investigate the prevalence of CAEV in goats from three hobbyist farms in the Republic of Tatarstan, Russia. Materials and Methods: We applied a multi-target approach to testing with both enzyme-linked immunosorbent assay (ELISA) and an in-house RT polymerase chain reaction test to investigate the prevalence of CAEV in goats. Animals from the three hobbyist farms were used in this study. The animals from two farms (n=13 for F1 and n=8 for F2) had clinical signs of arthritis and mastitis. In the third farm (n=15 for F3), all goats were home-bred and had no contact with imported animals. Results: CAEV antibodies (ELISA targets TM env and gag genes) were detected in serum samples from two farms (F1 and F2), indicating seroprevalence of 87.50-92.31%. Specific CAEV antibodies were also detected in milk samples. CAEV proviral DNA was detected in 53.85-62.50%. The results from all tests performed in the third farm (F3) were negative, indicating that all tests were 100% specific. Conclusion: The results showed that CAEV is circulating and present in small hobbyist goat farms in Russia. Serological and molecular tests could be important for programs to control and eradicate CAEV in Russia for hobbyist goat farms.

Caprine Arthritis Encephalitis Virus Is Associated with Renal Lesions

Caprine arthritis encephalitis virus (CAEV) is a monocyte/macrophage-tropic lentivirus that primarily infects goats resulting in a well-recognized set of chronic inflammatory syndromes focused on the joint synovium, tissues of the central nervous system, pulmonary interstitium and mammary gland. Clinically affected animals generally manifest with one or more of these classic CAEV-associated tissue lesions; however, CAEV-associated renal inflammation in goats has not been reported in the peer-reviewed literature. Here we describe six goats with chronic, multisystemic CAEV infections in conjunction with CAEV-associated renal lesions. One of the animals had CAEV antigen-associated thrombotic arteritis resulting in infarction of both the kidney and heart. These goats had microscopic evidence of inflammatory renal injury (interstitial nephritis) with detectable renal immunolabeling for CAEV antigen in three of six animals and amplifiable proviral sequences consistent with CAEV in all six animals. Cardiac lesions (vascular, myocardial or endocardial) were also identified in four of six animals. Within the viral promoter (U3) region, known transcription factor binding sites (TFBSs) were generally conserved, although one viral isolate had a duplication of the U3 A region encoding a second gamma-activated site (GAS). Despite the TFBS conservation, the isolates demonstrated a degree of phylogenetic diversity. At present, the clinical consequence of CAEV-associated renal injury is not clear.

Initial Multitarget Approach Shows Importance for Improved Caprine Arthritis-encephalitis Virus Control Program in Russia for Hobbyist Goat Farms

Aim: The aim of this study was to use a multi target approach to testing with both serological tests and an in-house real-time molecular test to investigate the prevalence of the caprine arthritis-encephalitis virus (CAEV) in goats from three hobbyist farms in the Republic of Tatarstan, Russia. Materials and Methods: We have approached the detection of using a multi target approach testing with both ELISA and an in-house real-time PCR test to investigate the prevalence of CAEV in goats. Animals from three hobbyist farms were used in this study. The animals from two farms (n=13 for F1 and n=8 for F2) had clinical signs of arthritis and mastitis. In the third farm (n=15 for F3), all goats were homebred and had no contact with imported animals. Results: CAEV antibodies (ELISA targets TM env and gag genes) were detected in serum samples from two farms (F1 and F2), indicating a seroprevalence 87.50-92.31%. Specific CAEV antibodies were also detected in milk samples. CAEV proviral DNA was detected in 53.85-62.50%. Results from all tests performed in the third farm (F3) were negative, indicting all tests were 100% specific.Conclusion: Results of this work show that CAEV is circulating and present in small hobbyist goat farms in Russia. Serological and molecular tests could be of importance for CAEV control and eradication programs in Russia for hobbyist goat farms.

Agreement between ECG values obtained in the sternal recumbent position and right lateral recumbency in goats

The aim of the study was to analyze if body positioning during electrocardiogram recording has an influence on the results in goats. Forty-seven Polish White Improved and Polish Fawn Improved goats from a large dairy herd selected for sanitary culling due to caprine arthritis-encephalitis virus (CAEV) infection, ranging from 2-12 years (median 5.5 years) were included in the study. ECG records were obtained from each goat in the sternal recumbent position and in right lateral recumbency using ASPEL AsCARD Mr. Silver machine with a frequency range of 0.05-150 Hz. The signals from leads I, II, III, aVR, aVL and aVF were recorded for 30 seconds. The mean values of P, QRS, T, PQ, QT, P-R duration (in sec) and P, Q, R, S, T waves amplitude (mV) were measured and analyzed. Values obtained in both positions did not differ significantly.

Study of metalloproteinases in the blood of goats experimentally infected with caprine encephalitis arthritis virus

Caprine arthritis encephalitis is a lentiviral disease that leads to considerable losses in goat farming. In the acute phase of viral infection, though antiviral antibodies are produced by the host’s immune system, they are not sufficient to be detected by serological tests. Acute infections begin with an incubation period, during which the viral genome replicates and host innate responses are initiated. Matrix metalloproteinases (MMPs) are enzymes that play an important role in the physiological and pathological processes of tissue remodeling. The present study aimed to evaluate the expression of MMPs and their activity in the blood serum of goats experimentally infected with caprine arthritis encephalitis virus (CAEV). Five dairy goats, aged 3-4 years, were intravenously inoculated with CAEV Cork strain (titer: 105-6 TCID50/mL) after being tested negative for CAEV thrice at consecutive intervals of 30 days using western blot analysis and nested-PCR. The study included three stages: S1 or pre-infection stage; S2 or seroconversion stage, corresponding to the occurrence of first seroconversion; and S3 or post-seroconversion stage, corresponding to 23 weeks after seroconversion. Zymography was performed for the samples using gelatin zymography gels (12.5%), which were subjected to electrophoresis at 170V, 1A, and 300W for 50-70 min. The density of MMP-2 was found to be lower at S1 (1456.20 pixels) than that at S2 and S3 (1943.80 and 2104.40 pixels, respectively) (P < 0.05); and the density of MMP-9 was found to be lower at S3 (133.60 pixels) than that at S1 and S2 (359.60 and 370.60 pixels, respectively). The density of proMMP-2 was low at S1 and S3 (130.45 and 145.20 pixels, respectively). On the other hand, the density of proMMP-9 was statistically different between S1 and S3 (89.22 vs. 415.60 pixels). Both proMMP-2 and proMMP-9 were absent at S2. Thus, MMP-2 and MMP-9 exhibited opposite behaviors depending on the stage of infection. As the greatest activity of MMP-2 was detected at stage S3, we suggest that MMP-2 can be used as a biomarker for complementary diagnosis of acute CAEV infection. In addition, the presence of proMMP-13 can be used to indicate active viral infection.

Initial Multitarget Approach Shows Importance for Improved Caprine Arthritis-encephalitis Virus Control Program in Russia for Hobbyist Goat Farms

In this study we have approached the detection of caprine arthritis-encephalitis virus (CAEV) using a multi target approach testing with both ELISA and an in-house real-time PCR test to investigate the prevalence of CAEV in goats from hobbyist farms in the Republic of Tatarstan, Russia. Animals from three hobbyist farms were used in this study. The animals from two farms (n=13 for F1 and n=8 for F2) had clinical signs of arthritis and mastitis. In the third farm (n=15 for F3), all goats were homebred and had no contact with imported animals. CAEV antibodies (ELISA targets TM ENV and GaG genes) were detected in serum samples from two farms (F1 and F2), indicating a seroprevalence 87.50-92.31%. Specific CAEV antibodies were also detected in milk samples. CAEV proviral DNA was detected in 53.85-62.50%. Results from all tests performed in the third farm (F3) were negative, indicting all tests apparent specificity of 100%. The results of this work show that CAEV is circulating and present in small hobbyist goat farms in Russia. Serological and molecular tests could be of importance for CAEV control and eradication programs in Russia for hobbyist goat farms.

Characterization of Signal Sequences Determining the Nuclear/Nucleolar Import and Nuclear Export of the Caprine Arthritis-Encephalitis Virus Rev Protein

Caprine arthritis-encephalitis virus (CAEV), a lentivirus, relies on the action of the Rev protein for its replication. The CAEV Rev fulfills its function by allowing the nuclear exportation of partially spliced or unspliced viral mRNAs. In this study, we characterized the nuclear and nucleolar localization signals (NLS and NoLS, respectively) and the nuclear export signal (NES) of the CAEV Rev protein. These signals are key actors in the nucleocytoplasmic shuttling of a lentiviral Rev protein. Several deletion and alanine substitution mutants were generated from a plasmid encoding the CAEV Rev wild-type protein that was fused to the enhanced green fluorescent protein (EGFP). Following cell transfection, images were captured by confocal microscopy and the fluorescence was quantified in the different cell compartments. The results showed that the NLS region is localized between amino acids (aa) 59 to 75, has a monopartite-like structure and is exclusively composed of arginine residues. The NoLS was found to be partially associated with the NLS. Finally, the CAEV Rev protein’s NES mapped between aa 89 to 101, with an aa spacing between the hydrophobic residues that was found to be unconventional as compared to that of other retroviral Rev/Rev-like proteins.

Pemphigus foliaceus in two pet Nigerian Dwarf goats

Two male Nigerian Dwarf pet goats from a group of three living in rural southern Wisconsin, USA, presented at the same time with an eight-month history of pruritus and marked crusting on head, axillae and inguinal regions. Parasite investigations were negative, and there was no response to antiparasitic treatment. Fungal and bacterial cultures did not reveal a cause. Histopathology was consistent with a diagnosis of pemphigus foliaceus, and goats were treated with immunosuppressive doses of injectable dexamethasone sodium phosphate. After six weeks of treatment, clinical remission was achieved, and immunosuppressive therapy was continued. Three months later, goat 2 developed presumptive viral pneumonia; necropsy reported presumptive caprine arthritis encephalitis virus. One year into treatment, goat 1 developed similar clinical signs and was euthanased. In goats, pemphigus foliaceus is rare and can be treated using glucocorticoids, but as in other species, chronic immunosuppression increases susceptibility to infections.