CONTRAST AGENT Gd‐EOB‐DTPA (EOB·Primovist®) FOR LOW‐FIELD MAGNETIC RESONANCE IMAGING OF CANINE FOCAL LIVER LESIONS

Contrast‐enhanced magnetic resonance (MR) imaging with a new liver‐specific contrast agent gadolinium‐ethoxybenzyl‐diethylenetriamine penta‐acetic acid (Gd‐EOB‐DTPA; EOB·Primovist®) was studied in 14 normal beagles and 9 dogs with focal liver lesions. Gd‐EOB‐DTPA accumulates in normally functioning hepatocytes 20 min after injection. As with Gd‐DTPA, it is also possible to perform a dynamic multiphasic examination of the liver with Gd‐EOB‐DTPA, including an arterial phase and a portal venous phase. First, a reliable protocol was developed and the appropriate timings for the dynamic study and the parenchymal phase in normal dogs using Gd‐EOB‐DTPA were determined. Second, the patterns of these images were evaluated in patient dogs with hepatic masses. The optimal time of arterial imaging was from 15 s after injection, and the optimal time for portal venous imaging was from 40 s after injection. Meanwhile, the optimal time to observe changes during the hepatobiliary phase was from 20 min after injection. In patient dogs, 11 lesions were diagnosed as malignant tumors; all were hypointense to the surrounding normal liver parenchyma during the hepatobiliary phase. Even with a low‐field MR imaging unit, the sequences afforded images adequate to visualize the liver parenchyma and to detect tumors within an appropriate scan time. Contrast‐enhanced MR imaging with Gd‐EOB‐DTPA provides good demarcation on low‐field MR imaging for diagnosing canine focal liver lesions.     

Hindbrain decompression in a dog with scoliosis associated with syringomyelia

A 6-month-old female Border Collie was examined because of a 1-month history of progressive curvature of the cervical portion of the vertebral column. Radiography revealed severe cervical and thoracic scoliosis. Cervical syringomyelia and hydrocephalus were observed by means of magnetic resonance imaging. Suboccipital craniotomy and laminectomy of the first cervical vertebra were performed, and substantial improvement in the scoliosis and syringomyelia was observed 3 months after surgery. No recurrences were seen during the first year after surgery.     

Dual-subtype vaccine (Fel-O-Vax FIV) protects cats against contact challenge with heterologous subtype B FIV infected cats

Fel-O-Vax FIV is a dual-subtype vaccine consisting of inactivated whole viruses of subtype A (Petaluma strain) and subtype D (Shizuoka strain). The efficacy of this vaccine against heterologous subtype A strain challenge was demonstrated, but it is unclear whether the result reflects efficacy in the field. In this study, we evaluated the efficacy of this vaccine against contact challenge by exposing both vaccinated and unvaccinated control animals with cats infected with Aomori-2 strain belonging to subtype B, a subtype prevalent in many regions of the world. Nineteen specific-pathogen-free (SPF) cats were divided into a vaccinated group (six cats), an unvaccinated control group (eight cats), and a challenge group (five cats), and maintained in the same room. Cats were monitored for FIV proviral DNA by nested PCR and for FIV-specific antibody levels by ELISA. After 1 year of commingling, each cat in the vaccinated group was given a booster dose. In addition, the original challenge group was removed and replaced with another challenge group of SPF cats, which were inoculated with the Aomori-2 strain. FIV infection was confirmed in four of the eight animals in the unvaccinated control group by the 29th week in the second year of commingling. In contrast, all of the animals were negative in the vaccinated group. These findings confirmed the efficacy of this vaccine against heterologous stains classified as subtype B, and suggested that the vaccine exhibits broad efficacy against genetically diverse FIV.     

Ventilatory failure and successful management for a dog with severe cervical meningioma

A 12-year-old intact male mongrel dog with a weight of 22 kg was referred with a complaint of progressive tetraparesis. Cervical myelography revealed an intradural-extramedullary mass at the second cervical vertebra. After computed tomography (CT) under general anesthesia, the patient showed dyspnea and cyanosis caused by insufficient movement of the chest wall. Positive pressure ventilation was therefore initiated. Hemilaminectomy and partial mass removal were performed 12 hr after the CT. The mass was histopathologically diagnosed as meningioma. Gradual weaning from the mechanical ventilation lasted for 80 hr after the operation. The patient eventually recovered from the ventilatory failure and the tetraparesis at approximately 6 and 14 days after the operation, respectively.     

Preventive effect of hyaluronic acid on the suppression of attachment and migration abilities of bovine chondrocytes by IL-1alpha in vitro

Attachment and migration of bovine chondrocytes cultured in vitro were significantly suppressed by the addition of interleukin (IL)-1alpha at the concentration of 1 ng/ml or more (p<0.05). The application of hyaluronic acid (HA) at the concentration of 10 micro g/m l or more significantly recovered the attachment of chondrocytes (p<0.05) and the application of HA at 100 micro g/ml concentration recovered the migration of chondrocytes suppressed by IL-1alpha. These results suggest that the application of HA for inflammatory arthropathies or chondrocyte transplantation might be helpful to preserve the properties of chondrocytes and its extracellular matrix against inflammatory conditions.     

Efficacy of intravaginal progesterone administration combined with prostaglandin f(2alpha) for cystic ovarian disease in Japanese Black cows

The objective of this study was to investigate cystic ovarian disease (COD) in commercial Japanese Black cows and to evaluate the efficacy of 7-day insertion of an intravaginal progesterone insert (CIDR) combined with prostaglandin F(2alpha) (PGF(2alpha)) at CIDR removal. Experiment 1 was conducted to group cysts into 4 patterns based on alteration of plasma progesterone (P(4)) concentrations on d -7 and d 0 (=CIDR insertion) with 1.0 ng/ml as the cut-off level by ultrasonographic examination of 28 cows with COD that were >or=40 days postpartum and anoestrous after calving. In Experiment 2, a total of 55 cows under the same conditions as in Experiment 1 were utilized, and the same regimen as in Experiment 1 was performed without 7 days of pre-observation before treatment. As a result, 92.9% of CLs on d 21 were highly formed in Experiment 1 and 83.6% were highly formed in Experiment 2. The conception rates within 60 days after CIDR removal were also satisfactory high and were 71.4% and 54.5%, respectively. There were no differences in any overall reproductive parameters between Experiments 1 and 2 (P>0.05). The average days between CIDR removal and conception were 24.4 +/- 5.3 and 24.0 +/- 6.5 days, respectively (P>0.05); therefore, the conception dates of the cows in Experiment 2 were at least 7 days earlier compared with Experiment 1. In conclusion, treatment with a CIDR and PGF(2alpha) against COD could minimize the risk of incorrect treatment and provide sufficient reproductive performance in Japanese Black cows.     

Development of a pen-site test kit for the rapid diagnosis of H7 highly pathogenic avian influenza

As well as H5 highly pathogenic avian influenza viruses (HPAIV), H7 HPAIV strains have caused serious damages in poultry industries worldwide. Cases of bird-to-human transmission of H7 HPAIV have also been reported [11]. On the outbreak of avian influenza, rapid diagnosis is critical not only for the control of HPAI but also for human health. In the present study, a rapid diagnosis kit based on immunochromatography for the detection of H7 hemagglutinin (HA) antigen of influenza A virus was developed using 2 monoclonal antibodies that recognize different epitopes on the H7 HAs. The kit detected each of the tested 15 H7 influenza virus strains and did not react with influenza A viruses of the other subtypes than H7 or other avian viral and bacterial pathogens. The kit detected H7 HA antigen in the swabs and tissue homogenates of the chickens experimentally infected with HPAIV strain A/chicken/Netherlands/2586/03 (H7N7). The results indicate that the present kit is specific and sensitive enough for the diagnosis of HPAI caused by H7 viruses, thus, recommended for the field application as a pen-site test kit.     

Case of Pregnancy in Two Cows with Unicorn Horn of the Uterus either by Artificial Insemination at Ipsilateral or Embryo Transfer at Contralateral Corpus Luteum in the Ovary

Two Holstein heifers and a cow were diagnosed with White Heifer Disease by ultrasonography. Case 1 was a 14 month-old heifer with aplasia of both sides of the uterine horn. In case 2, a primiparous cow and case 3, an 18 month-old heifer, both showed aplasia of the right uterine horn. Case 2 became pregnant by artificial insemination at ipsilateral ovulatory follicle and corpus luteum in the left ovary, while case 3 became pregnant by embryo transfer at 7 days after oestrus with contralateral corpus luteum in the right ovary.     

Seasonal variation of paulownia witches’-broom phytoplasma in paulownia trees and distribution of the disease in the Tohoku district of Japan

Seasonal variation of paulownia witches’-broom (PWB) phytoplasma within different organs (leaves, branch and trunk bark and roots) in paulownia trees was investigated by the amplification of a PWB-specific DNA fragment by the polymerase chain reaction (PCR). In leaf samples, PWB phytoplasma was first detected in June and the incidence gradually increased. On the other hand, the PWB was detected at relatively low incidence in branch bark, trunk bark and roots and the incidence did not change among seasons. A survey of PWB in 27 fields in the Tohoku district of Japan showed that malformed flower buds were observed in paulownia trees in almost all of the fields. PWB-phytoplasma was also detected by PCR from paulownia trees in almost all of the fields in Iwate and Fukushima Prefectures. The frequencies of trees in which phytoplasma was detected by PCR were higher than those in which symptoms were observed. These results indicated that PCR amplification of a PWB-specific DNA fragment is an effective tool for practical diagnose and that PWB is widely distributed in the Tohoku district of Japan.