Identification of Mycoplasma capricolum subspecies capripneumoniae and Mycoplasma arginini by culture, PCR, and histopathology in pneumonic lungs of slaughtered goats in Mashhad, Iran.

Background: A number of Mycoplasma spp., often referred to as the Mycoplasma mycoides (Mm) cluster can produce respiratory tract infections in goats; however, only Mycoplasma capricolum subspecies capripneumoniae (Mccp) is considered to causecontagious caprine pleuropneumonia. Aims: Isolation and identification of M. capricoluum subspecies capripneumoniae and M. arginini from the pneumonic lungs of slaughtered goats and their association with pathological changes. Methods: Lungs of 2000 goats slaughtered at an industrial abattoir in Mashhad, Iran, were examined for the presence of gross pneumonic lesions. Fifty affected lungs were selected for pathology, culture, and molecular (PCR) studies for the presence of Mycoplasma species. DNA was extracted from lung tissue samples and replicated using genus and species specific primers for Mycoplasma. Results: Grossly, consolidation and dark red to grey discoloration in the cranioventral to caudal lobes in fibrinopurulent bronchopneumonia and rubbery texture associated with rib impressions on the costal surfaces of the diaphragmatic lobes in interstitial pneumonia were observed. Histopathologically, bronchointerstitial pneumonia in 40 (80%), and fibrinopurulent bronchopneumonia in 10 (20%) of affected goats were diagnosed. The evidence of Mycoplasma growth such as turbidity and Mycoplasma colonies on the Mycoplasma agar plates was observed in 2 (4%) of samples. Genus-specific Mycoplasma DNA was identified in 11 (22%) of samples. Of them, 3 (6%) and 3 (6%) of tissue lung samples were positive for M. capricolum subspecies capripneumoniae and M. arginini, respectively, by PCR. Conclusion: Our results showed that M. capricolum subspecies capripneumoniae and M. arginini were the two agents that can involve lung consolidation and pneumonia in goats.

Identification of Mycoplasma ovipneumoniae and Mycoplasma arginini in sheep with pneumonia in North East of Iran.

BACKGROUND: Pneumonia due to Mycoplasma infections can cause serious health problems and economic losses in small ruminants industry. AIMS: The aim of this study was isolation and identification of Mycoplasmas in sheep naturally infected with pneumonia in Northeastern Iran. METHODS: This study used histopathology, culture and polymerase chain reaction (PCR) to examine samples from 50 lungs of sheep naturally infected with Mycoplasmas. RESULTS: Grossly, irregular consolidation with lobular or lobar to diffuse pattern in the cranioventral to caudal lobes of affected lungs were observed. Histopathologically, bronchointerstitial pneumonia in 38 (76%), and purulent to fibrinopurulent bronchopneumonia in 12 (24%) affected sheep were diagnosed. DNA was extracted from lung tissue samples and replicated using genus and species specific primers for Mycoplasma. Mycoplasma growth was observed in 3 (6%) of a total of 50 lung samples. Genus-specific Mycoplasma DNA was identified by PCR in 12 (24%) of samples. Two (4%) and 7 (14%) samples of these 12 cases were positive for reaction with species-specific primers of Mycoplasma ovipneumoniae and Mycoplasma arginini, respectively. CONCLUSION: Our results showed that M. ovipneumoniae and M. arginini were the two agents that can be involved in inducing lung consolidation and pneumonia in sheep and PCR was more successful than the culture in detecting Mycoplasmas.

Persistent bovine viral diarrhea virus (BVDV) infection in cattle herds.

Bovine viral diarrhea virus (BVDV) is a significant pathogen associated with gastrointestinal, respiratory, and reproductive diseases of cattle worldwide. It causes continuous economic losses to the cattle industry primarily due to decreased reproductive performance. The ability of virus to cross the placenta during early pregnancy can result in the birth of persistently infected (PI) calves. Persistently infected animals are generally much more efficient transmitters of BVDV than transiently or acutely infected animals because they are capable of shedding large quantities of virus throughout their lives and are considered the primary reservoirs for BVDV. Due to the nature of viral infections, there is no treatment to fully cure an animal of a viral infection. All control programs which are in use in many countries of the world, mainly depend upon the detection of PI animals, eliminating them and preventing their return into the herds. Detection of PI animals at early stage, particularly soon after birth is of significant benefit to implement BVDV control programs. Available diagnostic tests such as virus isolation (VI), immunohistochemistry (IHC), Antigen-Capture ELISA (ACE), and reverse transcriptase polymerase chain reaction (RT-PCR) are used for detection of PI cattle. Each method to detect BVDV has advantages, disadvantages, and applicability for different diagnostic situations. The reliability of diagnostic tests is optimized by choosing the appropriate sampling strategy on the basis of animal age.

Molecular characterization and phylogenetic analysis of bovine viral diarrhea virus in dairy herds of Fars province, Iran.

Bovine viral diarrhea virus (BVDV) is one of the most important viral pathogens of cattle worldwide. The aim of present study was to determine the molecular characterization and phylogenetic analysis of BVDV infection in dairy herds of Fars province, Iran. For initial screening, a total of 400 blood samples were collected from 12 industrial dairy herds with previous history of diarrhea, abortion or birth of weak calves and analyzed using reverse transcription-polymerase chain reaction (RT-PCR) on buffy coat. In the next step, blood samples and also ear notch biopsies were collected from 100 cattle of infected farms three weeks later which were subsequently tested by antigen capture ELISA (ACE), RT-PCR and immunohistochemistry (IHC). The results of nested RT-PCR were successful in 16 out of 400 buffy coat samples (4%) in the initial screening. Also, 8 out of 100 samples (8%) were positive by all practiced tests including RT-PCR, ACE and IHC on buffy coat, serum and skin samples, respectively. Immunoreactivity for bovine BVDV antigen as brown, coarsely to finely granular was observed within the cytoplasm of epidermic epithelial cells, hair follicles and subcutaneous stromal cells. Genetic sequence analyses showed both genotypes, BVDV-1 and BVDV-2. The new isolates were identified as BVDV1-FarsA, BVDV1-FarsB and BVDV2-FarsA in the phylogenetic tree. Since both genotypes of the virus are present in the region, our findings emphasize the importance of monitoring BVDV infection in cattle and suggest detection and elimination of PI animals for controlling and eradication of BVDV in Fars province.

Pathological, bacteriological, and molecular characteristics of natural outbreaks of Johne's disease in goats of Fars Province, Iran.

OBJECTIVE/BACKGROUND: Johne's disease, also called paratuberculosis, is a very important chronic infectious disease of ruminants worldwide. The causative agent is an acid-fast bacterium, Mycobacterium avium paratuberculosis (MAP). Finding a precise method for detecting MAP is essential for the control and eradication of this disease in small ruminant herds. METHODS: In this study, appropriate samples were obtained from the ileum, cecum, colon, and mesenteric lymph nodes of 10 suspected naturally infected goats. Each sample was divided to two parts: the first part was stored at -20°C for bacteriologic culture and the second part was placed in 10% neutral formalin for molecular and histopathologic examination. To isolate MAP, the double incubation method was used for decontaminating the tissues and Middlebrook 7H9 broth-based culture associated with OADC (oleic acid, albumin, dextrose, and catalase) supplement with/without mycobactin J were used. Polymerase chain reaction (PCR; IS 900) was performed for media with positive acid-fast staining. RESULTS: Acid-fast staining was positive in 40% of ileum samples, 50% of cecum samples, 40% of colon samples, and 50% of lymph node samples with mycobactin J and in 60% of ileum samples, 60% of cecum samples, 40% of colon samples, and 40% of lymph node samples without mycobactin J. All samples were confirmed by IS 900 PCR assay. Diffuse granulomatous enteritis with multibacillary lesions and paucibacillary multifocal lymphadenitis associated with calcification were diagnosed histopathologically. CONCLUSION: MAP detection in intestinal content and in tissues is quite necessary for the diagnosis, control, and eradication of this disease in small ruminant herds.

Experimental Neospora caninum infection in domestic bird's embryonated eggs.

To date, there are no reports regarding comparison between different bird species in Neospora. caninum infection. In the present study 70 embryonated eggs from quail, partridge, broiler and egg laying chickens were divided into 7 groups equally. Six groups in each species were inoculated with different dilutions (10, 10(2), 10(3), 10(4), 10(5), and 10(6)) of tachyzoites/embryonated egg in the chorioallantoic membrane and the seventh group was considered as control. The mortality rates and clinical signs were studied. All the egg laying chickens and some of the broiler chickens and quails showed neurologic signs like. The results revealed that the mortality rate was dose dependent in broiler chicken embryonated eggs. But mortality rate was dose independent in egg laying chickens and quail. Partridge revealed 100 % mortality rate in all doses. The LD50 in broiler chicken embryonated was 10(2.3). In conclusion, LD50 in the broiler chickens is the lowest between different animal models which shows that the broiler chicken embryonated egg is the best animal model for experimental inducing of neosporosis. Partridge is the most susceptible bird to N. caninum infection. These results reinforce that there is genetic susceptibility to N. caninum in chickens like mice and provide new insights to reach an inexpensive and available animal model for N. caninum infection.

Clinical and morphopathological characteristics of an enzootic occurrence of acute coenurosis (Coenurus cerebralis) in a sheep herd.

In this study, 30 sheep from a flock suddenly showed acute neurological symptoms associated with more than 30 % mortality. At necropsy, thickening associated with congestion and turbidity of meningeal membranes particularly on cerebellum, focal to multifocal necrotic areas and whitish spots measuring 1 to 3 cm in diameter were observed in the cortex of cerebrum and cerebellum. Grossly, numerous white tracts were also observed in the myocardium. Histopathologically, the cross sections of coenurus larvae associated with necrotic suppurative meningoencephalitis were observed. Multiple necrotic areas were also observed in the gray matter of cerebellum due to migration of the larvae with an extensive infiltration of eosinophils and neutrophils. In the heart, multifocal granulomatous myocarditis was diagnosed. No growth was seen in bacterial cultures of the brain and heart. Also, no bacteria were seen in these tissues stained with Ziehl-Neelsen and Brown-Brenn Gram stain. On basis of gross and histopathologic lesions, acute coenurosis was diagnosed. Unlike chronic coenurosis, acute form of the disease rarely reported in sheep.

Giant hydronephrosis and secondary pyelonephritis induced by Salmonella dublin in a Holstein calf.

Hydronephrosis occurs as a congenital or an acquired condition following obstruction of the urinary tract. In this study, a four month old male Holstein calf with emaciation, growth retardation and a poor dry scruffy hair coat was examined because of remarkable distention of right abdomen. At necropsy, right kidney was hydronephrotic as a very big fluid-filled round pelvis with the presence of multilocular cysts bulged from the cortical surface. With sectioning, more than 10 L of bloody fluid poured out from this sac. Microscopic examination showed severe atrophy of cortical tissue and fibrosis of the medulla. Also, the dilated pelvis was composed of fibrinous exudate and necrosis of epithelium associated with multifocal aggregations of neutrophils and bacterial microcolonies. In a culture and serotyping of isolated bacteria, Salmonella dublin was determined. In conclusion, S. dublin induced pyelonephritis secondary to congenital giant hydronephrosis is the first report in cattle in the world.

Eimeria arloingi: further studies on the development of some endogenous stages.

The present study investigated the ultrastructural characteristics of gamogony and oocyst wall formation of Eimeria arloingi in experimentally infected kids. The 18 newborn animals allocated to 3 equal groups. Two of groups, A, B were inoculated with a single dose of 1×10(3) and 1×10(5) sporulated oocysts of E. arloingi, respectively. At 7, 14, 21, 28, 35, and 42days postinoculation (DPI), 1 kid from each group was necropsied for ultrastructural studies. Transmission electron microscopy was used to screen for the presence of developmental stages of the parasite. All stages of microgametocyte and macrogametocyte developments and also oocyst wall formation were observed from 7 to 42DPI. Different stages of schizigony accompanied by marked proliferation of endoplasmic reticulum, mitochondria and several granular dividing nuclei were diagnosed in the affected epithelial cells. Young microgamonts were recognizable by an electron lucent parasitophorous vacuole and several dividing nuclei with prominent nucleolar and peripheral chromatin in the cytoplasm. At a later stage, the nuclei began to elongate and a single mitochondrion and two basal bodies were observed in close proximity nucleus. These bodies eventually protruded from the surface of the gametocyte and formed two flagellar structures. Up to 80-120 microgametes were produced per microgamont. Macrogamonts were recognized by the presence of wall-forming bodies of types 1 and 2. Electron lucent WFB2 appeared earlier than the electron denser WFB1 during the process of macrogametogenesis. The outer layer of the oocyst wall was formed by the release of the contents of WFB1 at the surface to form an electron dense layer. The WFB2 appeared, subsequently, to give rise to the electron lucent inner layer. WFB1 plays a major role in oocyst wall formation.

Genetic characterization and phylogenetic analysis of Eimeria arloingi in Iranian native kids.

Among the 16 species of Eimeria from goats, Eimeria arloingi and Eimeria ninakohlyakimovae are regarded as the most pathogenic species in the world and cause clinical caprine coccidiosis. E. arloingi is known to be an important cause of coccidiosis in Iranian kids. Molecular analyses of two portions of nuclear ribosomal DNA (internal transcribed spacer1 (ITS1) and 18S rDNA) were used for the genetic characterization of the E. arloingi. Comparison of the sequencing data of E. arloingi obtained in the present study (ITS1: KC507793 and 18S rDNA: KC507792) with other Eimeria species in the GenBank database revealed a particularly close relationship between E. arloingi and Eimeria spp. from the cattle and sheep. The phylogram based on the ITS1 sequences shows that the E. arloingi, Eimeria bovis, and Eimeria zuernii formed a distinct group separate from the other remaining Eimeria spp. in cattle and poultry. In pairwise alignment, 18S rDNA sequence derived from E. arloingi showed 99% similarity to Eimeria ahsata with differences observed at only three nucleotides. This study showed that the ITS1 and 18S rDNA gene are useful genetic markers for the specific identification and differentiation of Eimeria spp. in ruminants.

Lipoma of the urinary bladder in a cat.

A 7-year-old male Persian cat was referred for necropsy examination a with history of progressive abdominal distention, dysuria, polyuria, colic and death. At necropsy examination, a raised white unencapsulated mass (3×6×4cm) was found on the mucosal surface of the bladder. The mass was lobulated with soft consistency similar to that of adipose tissue. Microscopical examination revealed cells identical to those of normal adipose tissue. On the basis of the gross and microscopical findings, the lesion was diagnosed as a lipoma. This tumour has not been recorded previously in the urinary bladder of a cat.

Multicentric fibromyxoid peripheral nerve sheath tumor (multicentric schwannoma) in a dromedary camel (Camelus dromedarius): morphopathological, immunohistochemical, and electron microscopic studies.

During postslaughter inspection of a 4-year-old male dromedary camel (Camelus dromedarius), numerous small nodules to large masses up to 4 cm in diameter were found on the serosal surfaces of forestomachs, large intestines, mesentery, liver, and spleen. Grossly, the masses were discrete, round, smooth, and white to gray that bulged from the serosal layer. Cut surfaces of the masses were discrete, round, white, and relatively homogeneous without any necrotic foci. Histopathologically, the masses were encapsulated and composed of a mixture of round and spindle-shaped cells in loose whorls of neoplastic cells with small elongated hyperchromatic wavy nuclei and a small amount of pale eosinophilic, poorly defined cytoplasm. Masson's trichrome staining showed mild amounts of collagen fibers forming an irregular, loose stroma. In immunohistochemistry, immunoreactivity for the Schwann cell marker (S100) was diffusely positive in the neoplastic cells. The immunoreactivity for CK, c-kit, and CD34 were negative. Ultrastructural examination confirmed the tumor was entirely formed of neoplastic Schwann cells. On the basis of the histopathological, immunohistochemical, and ultrastructural findings, the tumors were diagnosed as multicentric fibromyxoid peripheral nerve sheath tumor (multicentric schwannoma). This tumor has not been previously recorded in camel worldwide.

Immunohistopathological findings in the lungs of calves naturally infected with Mycoplasma bovis.

Histology and immunohistochemistry were used to analyse the lesions and distribution of Mycoplasma bovis antigen in the lungs of 18 naturally infected calves. Microscopic examination of pneumonic lungs revealed two distinct patterns of necrosis and inflammation. The first pattern was observed in six of 18 (33.3%) calves in which microscopic lesions were characterized by large irregular areas of coagulative necrosis surrounded by a dense zone of degenerated neutrophils. Moderate amounts of mycoplasmal antigen were in the centre and periphery of these necrotic foci and, to a lesser extent, in mononuclear cells of the peribronchial lymphoid tissue. The second pattern was observed in 18 of 18 (100%) calves and consisted of rounded foci of caseous necrosis composed by granular eosinophilic material surrounded by a rim of granulation tissue. Large amounts of M. bovis antigen were detected in the centre and periphery of these necrotic foci and, to a lesser extent, in the peribronchial lymphoid tissue, and alveolar and interstitial macrophages. It was concluded that both caseous and coagulative necrosis of the lung parenchyma was primarily caused by M. bovis. Infection with M. bovis should be suspected in bovine necrotic bronchopneumonia, particularly in cases in which the pulmonary necrosis is part of a pyogranulomatous inflammation centred around airways. The pattern of caseous necrosis with pyogranulomatous inflammation is characteristic of M. bovis infection while the pattern of coagulative necrosis is similar to and must be differentiated from Mannheimia haemolytica and Haemophilus somnus infection.

Ileoileal intussusception associated with coccidiosis in sheep.

Postmortem examination of a 3-year-old male Iranian native sheep with a history of anorexia and severe colic, revealed an intussusception of the small intestine, 30 cm proximal to the ileocaecal junction. Scattered hyperplastic lesions were present in the jejunal and ileal mucosa especially in intussuscipien. Microscopic examination of these lesions showed severe papillary hyperplasia of the epithelium associated with developmental stages of coccidia in the epithelial cells. An unusual type of intussusception and the presence of the proliferative nodular form of coccidiosis in the intestinal wall of intussuscipien suggested that coccidiosis could be considered as the possible cause of the problem.