Long-term effects of iopamidol as a contrast medium for computed tomography in Cloudy Catsharks Scyliorhinus torazame.

OBJECTIVE: The use of computed tomography (CT) in aquarium animals, including elasmobranchs, has increased dramatically. To take advantage of CT, contrast medium is used to enhance internal organs and provide contrast since elasmobranchs lack visceral fat. In this study, the contrast effects of iopamidol were examined for up to 260 days after intravenous administration to establish the time course of the CT values for the target organs in eight mature Cloudy Catsharks Scyliorhinus torazame. METHODS: A micro-CT system was used to measure the CT values of the designated region of interest in the target organs (ventricular cavity, kidneys, liver, gallbladder, ovarian follicles, uterine horn cavity) over time and the eggs laid, following administration of iopamidol (700 mg of iodine/kg). RESULT: The CT values of the ventricular cavity and kidneys peaked at 30 min and showed low values after day 22. The CT values for the liver increased over time and peaked at day 200, whereas values for the gallbladder and ovarian follicles peaked on day 6, with the gallbladder showing a low value and the ovarian follicles still showing a high value on day 260. Computed tomography images with identifiable enhancement within bilateral uterine horns were followed from days 1 to 35. The mean and maximum CT values of yolk and jelly in eggs laid after day 30 were significantly higher than the values for eggs laid up to day 29; embryonic development was confirmed in 88.7% of the eggs. CONCLUSION: There was no mortality or morbidity of the sharks during the experiment, indicating that the administration of iopamidol at 700 mg of iodine/kg did not result in any adverse effects for 260 days. This is the first study to describe the long-term contrast effects of iopamidol, thus contributing new information about the application of contrast studies in Cloudy Catsharks.

Contrast-enhanced computed tomography and cross-sectional anatomy of the trunk in the brownbanded bamboo shark (Chiloscyllium punctatum).

Computed tomography (CT) is used in veterinary medicine for the diagnosis of bones and soft tissue diseases in various species. In addition, CT has recently been used to diagnose aquatic animals, including Selachimorpha, which are difficult to diagnose out of water. However, because Selachimorpha do not have adipose tissue in the coelomic cavity, the coelomic organs cannot be fully identified using non-contrast CT (NCCT). The aim of this study is to present the anatomical features of the cadaver, NCCT, and contrast-enhanced CT (CECT) as well as the change in CT values of the coelomic organs and musculature of the brownbanded bamboo shark. NCCT scans were performed under anaesthesia in one male and one female shark. CECT was performed 30 min after iopamidol was administered intravenously. The sharks were euthanized, frozen at -20°C, and sliced in the same position in which they were scanned. Using electric band saw, 10-mm transversal sections were obtained. The anatomical structures of both males and females were identified by transversal sections, and CT images homologous to transversal sections were then selected. Sagittal and coronal CECT images were also obtained to facilitate understanding of the location and size of coelomic organs. Although bone structure and air in organs could be sufficiently discriminated on NCCT image, the coelomic organs were almost indistinguishable. On the other hand, CECT images obtained sufficient contrast to identify most coelomic organs in addition to bone and air. The results provide an atlas of a cross-sectional anatomy and CECT images, which is useful information for the medical diagnosis of coelomic organs in live Selachimorpha.

Dystrophin-deficient muscular dystrophy in a Toy Poodle with a single base pair insertion in exon 45 of the Duchenne muscular dystrophy gene.

A 10-month-old, intact male Toy Poodle was referred for a postural abnormality. Blood biochemical tests revealed a marked increase in plasma creatine phosphokinase (CPK) concentration. The isoenzyme test showed that 99% of serum CPK consisted of CPK-MM. Histopathological evaluation of muscle biopsy samples confirmed scattered degeneration and necrosis of myofibers. Immunohistochemistry for dystrophin showed an absence of staining in muscle cells. Based on these findings, the dog was diagnosed with dystrophin-deficient muscular dystrophy. Whole genome sequencing using genomic DNA extracted from blood revealed a single base pair insertion in exon 45 of the Duchenne muscular dystrophy (DMD) gene. This is the first report on muscular dystrophy in Toy Poodles and identified a novel mutation in the DMD gene.

Retrospective evaluation of nimustine use in the treatment of feline lymphoma.

BACKGROUND: Nimustine, similar to lomustine, is an alkylating agent from the nitrosourea family. There have been some reports regarding lomustine treatment for tumour-bearing cats. However, information regarding nimustine treatment for tumour-bearing cats is limited. OBJECTIVES: To retrospectively evaluate adverse events and clinical outcomes in tumour-bearing cats receiving nimustine. METHODS: Information regarding diagnosis, treatment condition, adverse events, and clinical outcomes was collected in tumour-bearing cats receiving nimustine through reviews of medical records. RESULTS: Nine cats with lymphoma were treated with nimustine in the primary therapy (n = 2) and in the rescue therapy (n = 7). Median starting dose of nimustine was 25 mg/m2 (range: 20-30 mg/m2 ) with dosing interval of three weeks and 1-11 administrations. Adverse events were mild gastrointestinal toxicity (grade 1) including diarrhoea (n = 2) and vomiting (n = 2) and mild myelosuppression (grade 1 or 2) including thrombocytopenia (n = 3) and neutropenia (n = 1). No severe adverse events were observed. Progression-free survival durations among cats receiving nimustine in the primary therapy and in the rescue therapy were 274-688 days (median: 481 days) and 9-671 days (median: 102 days), respectively. Overall survival durations among cats receiving nimustine in the primary therapy and in the rescue therapy were 275-745 days (median: 510 days) and 14-671 days (median: 109 days), respectively. CONCLUSIONS: Nimustine was well tolerated and showed clinical outcomes similar to lomustine in cats with lymphoma. These findings suggest that nimustine might be an alternative to lomustine in the treatment of feline lymphoma.

The Establishment of an Optimal Protocol for Contrast-Enhanced Micro-Computed Tomography in the Cloudy Catshark Scyliorhinus torazame.

The purpose of this study was to determine the optimal imaging protocol for contrast-enhanced computed tomography (CECT) using micro-CT (µ-CT) for the posterior cardinal vein (PCV), dorsal aorta (DA), hepatic portal vein (HPV), kidney, liver, cephalic arteries (CAs), and gills of Cloudy Catsharks Scyliorhinus torazame. Additionally, we examined the availability of CECT screening for the coelomic organs. Different doses of iopamidol (100, 300, 500, and 700 mg iodine [mgI]/kg) were administered intravenously for 20 s in six sharks. The CT scans from the pectoral girdle to the pelvic girdle were performed at 0-600 s after administration. Contrast-enhanced CT imaging of the CAs, gills, and coelomic organs was examined. Assessment of the signal enhancement value revealed that the PCV was easily visualized with all contrast doses at 25 s. The CAs, gills, and DA were visible at a slightly higher dose (CAs and gills: 200 mgI/kg at 40 s; DA: 300 mgI/kg at 50 s). The HPV was obvious at a dose of at least 500 mgI/kg after a 150-s delay. The parenchyma of the kidney had a contrast effect at 300 mgI/kg, 150 s after the contrast effect of the renal portal system disappeared. The liver, which stores a lot of lipids, had poor overall contrast enhancement that was optimized at the highest dose of 700 mgI/kg. Contrast-enhanced CT screening at 700 mgI/kg and 150 s is likely to obtain the optimal imaging of the reproductive organs, such as the ovary, oviducal gland, uterus, and testis. The present findings can be applied not only to clinical practice but also to academic research and education on elasmobranchs in aquariums.

Canine idiopathic chylothorax: Anatomic characterization of the pre- and postoperative thoracic duct using computed tomography lymphography.

Surgical treatment has improved the prognosis of canine idiopathic chylothorax, although a recurrence of the disease occurs occasionally after the procedure. An improved understanding of possible causes for this recurrence would be helpful for prognosis and treatment planning in affected patients. In this retrospective case series study, we described the detailed pre- and postoperative computed tomographic lymphography (CTLG) imaging characteristics for a group of dogs with surgically confirmed idiopathic chylothorax. Preoperative CTLG was performed in 12 of 14 dogs diagnosed with idiopathic chylothorax. Thoracic ducts were present on the right side in 10 dogs, left side in one dog, and bilaterally in one dog. All the 14 dogs received a combination therapy of pericardiectomy and thoracic duct ligation (TDL) by video-assisted thoracoscopic surgery. One week after surgery, a postoperative CTLG was performed, and the thoracic ducts were apparent in seven of 14 dogs. Three dogs had an unchanged course of the thoracic duct, which could have resulted from a missed duct. Four dogs were identified as having a bypass formation: the oblique duct originated at the ligation site and connected to the duct on the other side. Our findings indicated that one of the possible causes for postoperative recurrence of chylothorax in dogs could be "invisible or sleeping" fine ducts that are collapsed and not visible in preoperative CTLG scans. After TDL causes a change in the pressure of lymphatic flow, these fine thoracic ducts may become apparent using postoperative CTLG.

Whole-genome analyses of extended-spectrum or AmpC ß-lactamase-producing Escherichia coli isolates from companion dogs in Japan.

The emergence and global spread of extended-spectrum or AmpC ß-lactamase (ESBL/AmpC)-producing Enterobacteriaceae in companion animals have led to the hypothesis that companion animals might be reservoirs for cross-species transmission because of their close contact with humans. However, current knowledge in this field is limited; therefore, the role of companion animals in cross-species transmission remains to be elucidated. Herein, we studied ESBL/AmpC-producing Enterobacteriaceae, Escherichia coli in particular, isolated from extraintestinal sites and feces of companion dogs. Whole-genome sequencing analysis revealed that (i) extraintestinal E. coli isolates were most closely related to those isolated from feces from the same dog, (ii) chromosomal sequences in the ST131/C1-M27 clade isolated from companion dogs were highly similar to those in the ST131/C1-M27 clade of human origin, (iii) certain plasmids, such as IncFII/pMLST F1:A2:B20/blaCTX-M-27, IncI1/pMLST16/blaCTX-M-15, or IncI1/blaCMY-2 from dog-derived E. coli isolates, shared high homology with those from several human-derived Enterobacteriaceae, (iv) chromosomal blaCTX-M-14 was identified in the ST38 isolate from a companion dog, and (v) eight out of 14 tested ESBL/AmpC-producing E. coli isolates (i.e., ST131, ST68, ST405, and ST998) belonged to the human extraintestinal pathogenic E. coli (ExPEC) group. All of the bla-coding plasmids that were sequenced genome-wide were capable of horizontal transfer. These results suggest that companion dogs can spread ESBL/AmpC-producing ExPEC via their feces. Furthermore, at least some ESBL/AmpC-producing ExPECs and bla-coding plasmids can be transmitted between humans and companion dogs. Thus, companion dogs can act as an important reservoir for ESBL/AmpC-producing E. coli in the community.

HSP110 expression in canine mammary gland tumor and its correlation with histopathological classification and grade.

Heat shock proteins (HSPs) play critical roles as molecular chaperones, thereby promoting cellular homeostasis. HSPs are overexpressed in many types of human tumors and their serum concentration is elevated in cancer patients. Recent studies have suggested that HSPs may promote tumorigenesis via interactions with tumor-related proteins. There are only a few studies that address the expression of HSPs in canine tumors. In our previous study, we identified elevated levels of HSP110 expression in canine mammary gland tumors (cMGTs). In this study, we examined both serum concentrations and tissue expression of HSP110 in dogs with cMGT. We found that serum HSP110 concentrations were not significantly different in a comparison between dogs with cMGT (3.44 ± 1.27 µg/mL) and healthy controls (3.23 ± 1.18 µg/mL). By contrast, significant differences in levels of HSP110 expression were identified in comparisons between simple carcinoma and benign mixed tumor (p = 0.001), simple carcinoma and non-neoplastic lesions (p < 0.001), complex carcinoma and benign mixed tumor (p = 0.015), complex carcinoma and non-neoplastic lesions (p < 0.001), simple adenoma and benign mixed tumor (p = 0.041), and simple adenoma and non-neoplastic lesions (p = 0.007). Similarly, significantly different levels of HSP110 expression were identified when comparing grade Ⅲ with non-neoplastic lesion (p = 0.026), grade Ⅱ with benign tumor (p = 0.015), grade Ⅱ with non-neoplastic lesion (p < 0.001), and grade Ⅰ with non-neoplastic lesion (p < 0.001). Taken together, our results indicate that expression of HSP110 correlates with the malignancy in this cohort of dogs diagnosed with cMGT. These findings also suggest that HSP110 is associated with tumorigenesis and the relative malignancy of cMGT.

Decreased serum zinc concentration in dogs with lymphocytic-plasmacytic enteritis, and its associations with disease severity and prognosis.

Human patients with inflammatory bowel disease may have poor prognosis with hypozincemia. However, there are limited data on zinc concentrations in the blood of dogs with lymphocytic-plasmacytic enteritis (LPE). The purpose of this study was to investigate the serum zinc concentration in dogs with LPE and its influence on disease severity and prognosis. Thirty-five dogs with LPE were recruited. Serum zinc concentration was measured using atomic absorption spectrometry. Hypozincemia was observed in 18/35 (51%) dogs with LPE. Serum zinc concentration was inversely correlated with histological and clinical severities. Overall survivals were significantly shorter in dogs with hypozincemia than in those without it. These findings suggest that serum zinc concentration is a useful biomarker for LPE severity and prognosis in dogs.

Efficacy of en bloc thoracic duct ligation in combination with pericardiectomy by video-assisted thoracoscopic surgery for canine idiopathic chylothorax.

OBJECTIVE: To compare the outcomes of pericardiectomy performed with conventional clipping thoracic duct ligation (C-TDL) to those with en bloc thoracic duct ligation (EB-TDL) using video-assisted thoracoscopic surgery (VATS) for canine idiopathic chylothorax. STUDY DESIGN: Retrospective consecutive case series. ANIMALS: Thirteen client-owned dogs with idiopathic chylothorax. METHODS: Medical records of dogs treated with pericardiectomy in combination with TDL by VATS without intraoperative contrast were reviewed. Five and seven dogs underwent C-TDL and EB-TDL, respectively, and 11 dogs were evaluated by preoperative and 7- to 10-days-postoperative computed tomography-lymphography (CTLG). No clinical symptoms with absent or minimal pleural effusion was defined as clinical improvement. Long-term remission (LTR) was defined as rapid resolution of pleural effusion and no recurrence for more than 1 year. Anesthesia time, operation time, the duration of hospitalization, and time until pleural effusion resolution were compared. RESULTS: Clinical improvement was achieved in 91.7% of the cases (C-TDL, 4/5; EB-TDL, 7/7), excluding one case of intraoperative death. The LTR rate was significantly higher with EB-TDL (6/7 [85.7%]) than with C-TDL (1/5 [20%]). Anesthesia time, operation time, and time until pleural effusion resolution were significantly better with EB-TDL than with C-TDL. The rates of thoracic ducts visualization by postoperative CTLG were 100% (5/5) with C-TDL and 42.9% (3/7) with EB-TDL. CONCLUSION: En bloc TDL was an effective treatment for canine idiopathic chylothorax in this patient population. It compared favorably to C-TDL, although missed branches at the time of surgery may explain the difference between C-TDL and EB-TDL in this small population of cases. CLINICAL SIGNIFICANCE: En bloc TDL by VATS was an effective minimally invasive treatment for canine idiopathic chylothorax. Computed tomography-lymphography can be used for surgical planning and postoperative evaluation.

Correlation between toll-like receptor 4 and nucleotide-binding oligomerization domain 2 (NOD2) and pathological severity in dogs with chronic gastrointestinal diseases.

Toll-like receptor 4 (TLR4), nucleotide-binding oligomerization domain 2 (NOD2), and TNF-α play important roles in human inflammatory bowel diseases. The aim of this study was to elucidate the relationship between Toll-like receptor 4, NOD2, and TNF-α and the severity of chronic gastrointestinal diseases in dogs. We examined the expression levels of TLR4, NOD2, and TNF-α in the stomach, duodenum, ileum, colon, and rectum obtained from 21 dogs with chronic gastrointestinal disease, including inflammatory bowel disease, high-grade lymphoma, food responsive enteropathy, chronic pancreatitis, low-grade lymphoma, inflammatory colorectal polyp, and chronic colitis. Next, we demonstrated whether there is good correlation between the expression levels of TLR4, NOD2, and TNF-α and the histopathological analysis of each sample. We found that the level of TLR4 expression in the ileum of dogs with chronic gastrointestinal disease was positively associated with the histopathological severity. We also found that the level of NOD2 expression in the duodenum, stomach, and rectum was positively associated with the histopathological severity. However, there was no correlation between TNF-α expression in the 5 regions tested in this study and the histopathological severity. These findings indicate that TLR4 and NOD2 are remarkably associated with the severity of chronic gastrointestinal disease in dogs.

Prevalence of microorganisms associated with feline gingivostomatitis.

OBJECTIVES: Feline gingivostomatitis (FGS) is a painful chronic inflammatory disease of the oral cavity. The purpose of this study was to examine the frequency of detection of certain common feline bacteria and viruses to determine any potential associations with FGS. METHODS: A multicentre case-control study design was conducted. In total, 72 control cats and 32 cats with FGS were included in the study. Oral swabs were cultured for bacterial identification and a PCR assay was carried out to examine the infection of feline calicivirus (FCV), feline herpesvirus-1 (FHV-1), Chlamydia felis, Mycoplasma felis and Bordetella bronchiseptica. RESULTS: There was a significant difference in age distribution between the control and the FGS group. Based on a PCR assay, the positive rate of FCV was significantly higher in FGS cats than control animals. For other infectious pathogens, including FHV-1, C felis and M felis, there was no significant difference. Bacterial culture of oral swabs revealed that Pasteurella multocida was most frequently detected, but the detection rate was significantly lower in FGS cats. In FGS cats, the incidence of Enterococcus faecalis and anaerobic bacteria were more frequently isolated than in control cats. CONCLUSIONS AND RELEVANCE: This study indicates that the positive rate of FCV was significantly higher in cats with FGS, and the microflora of the oral cavity of cats with FGS might be disrupted, although additional studies are required to compare the oral microbiome in cats of a variety of ages.

Outcome of limb fracture repair in rabbits: 139 cases (2007-2015).

OBJECTIVE To evaluate outcome of limb fracture repair in rabbits. DESIGN Retrospective case series. ANIMALS 139 client-owned rabbits with limb fractures treated between 2007 and 2015. PROCEDURES Medical records were reviewed for information on fracture location, fracture treatment, and time to fracture healing. RESULTS 25 rabbits had fractures involving the distal aspects of the limbs (ie, metacarpal or metatarsal bones, phalanges, and calcaneus or talus). Fractures were treated in 23 of these 25 rabbits (external coaptation, n = 17; external skeletal fixation, 4; and intramedullary pinning, 2) and healed in all 23, with a median healing time of 28 days (range, 20 to 45 days). One hundred ten rabbits had long bone fractures, and fractures were treated in 100 of the 110 (external skeletal fixation, n = 89; bone plating, 1; intramedullary pinning, 3; and external coaptation, 7). The percentage of fractures that healed was significantly lower for open (14/18) than for closed (26/26) tibial fractures and was significantly lower for femoral (19/26) and treated humeral (4/6) fractures than for radial (23/24) or closed tibial (26/26) fractures. Micro-CT was used to assess fracture realignment during external skeletal fixator application and to evaluate fracture healing. CONCLUSIONS AND CLINICAL RELEVANCE The prognosis for rabbits with limb fractures was good, with fractures healing in most rabbits following fracture repair (109/123). Micro-CT was useful in assessing fracture realignment and evaluating fracture healing.

Report of fatal mixed infection with Cryptosporidium parvum and Giardia intestinalis in neonatal calves.

In the production and management of beef and dairy cattle, controlling diarrhea is one of the important concerns. Pathogenic agents of the disease, protozoan parasites including Cryptosporidium spp., are difficult to control, making prevention, diagnoses, and treatment of diarrhea. In the present study, we investigated a farm with a history of calf deaths over a period of 10 years in order to determine the cause of disease and to clarify the detailed distribution of the pathogens. In four examined calves that were reared in calf pens, all were positive with Cryptosporidium and/or Giardia, while the other breeding stock and adult cattle were negative. Molecular analyses revealed that the isolates from calves were C. parvum subtype IIaA15G2R1 as a zoonotic and G. intestinalis assemblage E. Other pathogenic bacteria and diarrhea-causing viruses were not detected. After treating the calf pens with boiling water and milk of lime (Ca[OH]2), oocysts of C. parvum and cysts of G. intestinalis were not found and no additional calves died. This is the first report to describe the mixed infection of both parasites in Japan.

Identification of Eimeria acervulina conoid antigen using chicken monoclonal antibody.

In the poultry industry, Eimeria spp. is one of the important pathogens which cause significant economic losses. We have previously generated a chicken monoclonal antibody (mAb), 6D-12-G10, with specificity for an antigen located in the apical cytoskeleton of Eimeria acervulina and with cross-reactive among Apicomplexan parasites, including other Eimeria spp., Toxoplasma, Neospora, and Cryptosporidium spp. Furthermore, the protein of Cryptosporidium parvum recognized by the 6D-12-G10 has been identified as elongation factor-1α (EF-1α). In the present study, to identify the target molecule of E. acervulina by the mAb, we performed two-dimensional Western blotting analysis. Finally, we found two positive molecules which are identified as EF-1α and a related protein. Our previous finding using C. parvum and the results in this study suggest that EF-1α could be associated with the invasion facilitated by the cytoskeleton at the apical region of zoites.

Localization of heat shock protein 110 in canine mammary gland tumors.

Heat shock proteins (HSPs) function as molecular chaperones in the regulation of protein folding, conformation, and assembly; in addition, they also protect cells from protein-protein aggregation resulting from cellular stress. Recently, HSPs were shown to be overexpressed in several human cancer cells compared with normal cells. HSPs are considered to be related to apoptosis-associated proteins, and inhibition of apoptosis promotes tumor growth. Canine mammary gland tumors have received a great deal of attention from researchers due to the many common biological and histological characteristics that they share with human tumors. We previously confirmed that HSP110 is a canine mammary gland tumor antigen and reported that HSP110 mRNA expression significantly increased in tumor tissue. We have now created a functional recombinant canine HSP110 protein and a rabbit anti-HSP110 polyclonal antibody. This recombinant protein can refold heat-denatured firefly luciferase at 42°C. Immunohistochemical analysis showed that HSP110 was mainly localized in the cytoplasm of epithelial and interstitial cells in canine mammary gland tumors. Extensive genomic research has revealed genetic similarities between humans and dogs; comparative oncological studies between these species have made remarkable progress. The results reported here contribute valuable oncological knowledge for the development of novel therapeutic methods in both veterinary science and human medicine.

Characteristics of bone fractures and usefulness of micro-computed tomography for fracture detection in rabbits: 210 cases (2007-2013).

OBJECTIVE: To characterize bone fractures and the usefulness of micro-CT for imaging fractures in pet rabbits. DESIGN: Retrospective case series. ANIMALS: 210 client-owned rabbits with bone fractures. PROCEDURES: Medical records of rabbits evaluated for bone fractures from 2007 through 2013 were examined. Information was collected on signalment and nature of fractures, and radiographic and micro-CT images of fractures were reviewed. RESULTS: Almost half (n = 95 [47.7%]) of fractures were in rabbits < 3 years old. Accidental fall was the most common cause. Vertebral fracture was the most common type of fracture with a nonneoplastic cause (n = 46 [23.2%]) and was most common in the L4-L7 region. The tibia was the most common site for limb fracture among all fractures with a nonneoplastic cause (45 [22.7%]). Twelve (5.7%) fractures had a neoplastic cause, and 7 of these were associated with metastatic uterine adenocarcinoma. Females were significantly more likely to have a fracture caused by neoplasia than were males. Compared with radiography, micro-CT provided more detailed fracture information, particularly for complicated fractures or structures (eg, skull, pelvic, vertebral, and comminuted limb fractures). CONCLUSIONS AND CLINICAL RELEVANCE: Findings were useful for understanding the nature of fractures in pet rabbits and supported the use of micro-CT versus radiography for fracture detection and evaluation.

Profiling of serum metabolites in canine lymphoma using gas chromatography mass spectrometry.

Canine lymphoma is a common cancer that has high rates of complete remission with combination chemotherapy. However, the duration of remission varies based on multiple factors, and there is a need to develop a method for early detection of recurrence. In this study, we compared the metabolites profiles in serum from 21 dogs with lymphoma and 13 healthy dogs using gas chromatography mass spectrometry (GC-MS). The lymphoma group was separated from the control group in an orthogonal projection to latent structure with discriminant analysis (OPLS-DA) plot using ions of m/z 100-600, indicating that the metabolites profiles in lymphoma cases differed from those in healthy dogs. The lymphoma group was also separated from the control group on OPLS-DA plot using 29 metabolites identified in all serum samples. Significant differences were found for 16 of these metabolites with higher levels in the lymphoma group for 15 of the metabolites and lower levels for inositol. An OPLS-DA plot showed separation of the lymphoma and healthy groups using these 16 metabolites only. These results indicate that metabolites profile with GC-MS may be a useful tool for detection of potential biomarker and diagnosis of canine lymphoma.

Elongation factor-1α is a novel protein associated with host cell invasion and a potential protective antigen of Cryptosporidium parvum.

The phylum Apicomplexa comprises obligate intracellular parasites that infect vertebrates. All invasive forms of Apicomplexa possess an apical complex, a unique assembly of organelles localized to the anterior end of the cell and involved in host cell invasion. Previously, we generated a chicken monoclonal antibody (mAb), 6D-12-G10, with specificity for an antigen located in the apical cytoskeleton of Eimeria acervulina sporozoites. This antigen was highly conserved among Apicomplexan parasites, including other Eimeria spp., Toxoplasma, Neospora, and Cryptosporidium. In the present study, we identified the apical cytoskeletal antigen of Cryptosporidium parvum (C. parvum) and further characterized this antigen in C. parvum to assess its potential as a target molecule against cryptosporidiosis. Indirect immunofluorescence demonstrated that the reactivity of 6D-12-G10 with C. parvum sporozoites was similar to those of anti-ß- and anti-γ-tubulins antibodies. Immunoelectron microscopy with the 6D-12-G10 mAb detected the antigen both on the sporozoite surface and underneath the inner membrane at the apical region of zoites. The 6D-12-G10 mAb significantly inhibited in vitro host cell invasion by C. parvum. MALDI-TOF/MS and LC-MS/MS analysis of tryptic peptides revealed that the mAb 6D-12-G10 target antigen was elongation factor-1α (EF-1α). These results indicate that C. parvum EF-1α plays an essential role in mediating host cell entry by the parasite and, as such, could be a candidate vaccine antigen against cryptosporidiosis.

Infectivity of Cryptosporidium andersoni Kawatabi type relative to the small number of oocysts in immunodeficient and immunocompetent neonatal and adult mice.

Cryptosporidium andersoni is a protozoan parasite found in many countries that invades the stomachs of primarily adult cattle. Unlike the isolates of C. andersoni in cattle from other countries, C. andersoni isolates from Japanese cattle can infect mice and were identified as a novel type and later defined as C. andersoni Kawatabi type. The biological characteristics of C. andersoni Kawatabi type have not yet been well documented. In the present study, we assess the infectivity of this type isolate in mice with different immune competence status and age. We found that inoculation of more than 1×10(4) oocysts is needed to establish infection in mature mice irrespective of immune status. All of the infected immunocompetent mice recovered after a patent period of approximately 20days. In immunodeficient mice, the pre-patent period was prolonged compared with that of 1×10(6) oocysts, but the pattern and the maximum shedding measured by the number of oocysts per day were almost identical. In neonatal immunocompetent and immunodeficient mice, inoculation with 1×10(4) to 10(5) oocysts was also needed to establish infection. Our results indicate that there is a threshold of oocysts needed to establish patent infection in the acidic conditions of the stomach.