VIRTUAL ENDOSCOPY OF DOGS USING MULTI-DETECTOR ROW CT

Virtual endoscopy uses CT data to display hollow viscera such as the stomach, duodenum and colon as if by real endoscopic observation. The results are independent of the operator skill because virtual endoscopy does not require direct manipulation of endoscopic equipment. The purpose of this study was to evaluate the utility of virtual endoscopy in small animals. Ten beagles were examined by conventional endoscopy and virtual endoscopy using multidetector CT. Virtual images were image-processed at a workstation designed for depicting virtual endoscopy using CT data. Virtual images were visually comparable with conventional endoscopic images, especially in the area of the angular incisure and pylorus. The advantages of virtual endoscopy are observation from any viewing angle, a reduced learning curve for diagnostic interpretation, quantification of lesion size in three dimensions and a potential for reducing anesthesia time. The disadvantages of virtual endoscopy are a lack of color recognition information, an inability to retrieve biopsy samples, limited visualization of the duodenum, artifacts from respiration/peristalsis motion and an inability to observe function. Based on our results, we suggest that conventional endoscopy is still superior to virtual endoscopy in dogs. However, as technology improves, virtual endoscopy may emerge as a suitable alternative or adjunctive diagnostic tool for certain digestive disorders in small animals.     

Breed Differences in Dopamine Receptor D4 Gene (DRD4) in Horses

Genetic polymorphisms in genes related to neurotransmitters or hormones affect personality or behavioral traits in many animal species including humans. In domestic animals, the allele frequency of such genes has been reported to be different among breeds and it may account for breed differences in behavior. In this study, we investigated breed differences in horses in the dopamine receptor D4 gene (DRD4), which has been reported to affect horse personality. We collected samples from seven horse breeds including those native to Japan and Korea, and compared the sequence of the DRD4 exon3 region among these breeds. We found that there were two types of polymorphisms (VNTR and SNPs) in the exon3 region, and some of them seemed to be breed-specific. In addition, we found that the allele frequency of G292A, reported to be associated with horse personality, differed greatly between native Japanese horses and Thoroughbred horses. The frequency of the A allele which is associated with low curiosity and high vigilance, was much lower in native Japanese horses (Hokkaido, 0.03; Taishu, 0.08) than in Thoroughbreds (0.62). This difference may account for breed differences in personality or behavioral traits. Further studies of the function of these polymorphisms and their effect on behavior are indicated.     

Development of embryos and larvae in the common Japanese conger Conger myriaster

Development of embryos and larvae in the common Japanese conger Conger myriaster was observed after artificial fertilization. Eggs were obtained from females matured artificially by hormone injections and milt was obtained from males matured naturally. Fertilized eggs were kept in seawater at 12–14°C. The first cleavage occurred at 4 h, epiboly began at 24 h, the embryonic body was formed at 38 h and hatching occurred at 84 h after insemination. Newly hatched larvae were approximately 2.5 mm (total length) and similar to those of Anguilla japonica in terms of external features. The mouth and anus opened on the 7th day after hatching. Pigments began to appear at the tip of the tail on the 10th day. The total length of the larvae reached approximately 8 mm on the 11th day. Eye pigmentation began on the 14th day. One larva lived for 19 days without food.     

Impact of aluminium stress on oxalate and other metabolites in Rumex obtusifolius

To understand alterations of oxalate and other metabolite levels induced by aluminium ion (Al³⁺) stress in Rumex plants, we measured the metabolites in R. obtusifolius using the capillary electrophoresis–mass spectrometry. Oxalate and its precursors (isocitrate and citrate) accumulated in leaves of R. obtusifolius after the Al³⁺ treatment at pH 4.5. Such increase was not observed under the acidic condition (pH 4.5) without Al³⁺. Principal component analysis showed organ‐specific changes in metabolite levels in R. obtusifolius by the Al³⁺ treatment. Highly positive correlations between oxalate and its precursors were revealed by hierarchical clustering and correlation analyses. An increase in oxalate content was consistently observed for three Rumex species (R. obtusifolius, R. crispus and R. japonicus) grown in the presence of Al³⁺. On the other hand, multivariate analyses revealed the differential alterations of other metabolite levels between R. obtusifolius and the other two Rumex species.     

Sex differences in cervical spinal cord and spinal canal development in Thoroughbred horses

Cervical vertebral stenotic myelopathy (CVSM), a common cause of cervical spinal cord compression, is a neurological disease characterized by general proprioceptive ataxia and weakness of hindlimbs that tends to develop in young adult Thoroughbred horses. Although male horses seem to be at increased risk for CVSM, the mechanism for the occurrence of sex differences in the prevalence of CVSM is still poorly understood. Hence, we hypothesized that sex differences in the development of cervical spinal cord and spinal canal would affect the development of CVSM. This study aimed to evaluate sex differences in the development of cervical spinal cord and spinal canal in Thoroughbred horses. A total of 29 Thoroughbred horses underwent computed tomographic myelography. Thereafter, the volumes of cervical spinal cord and spinal canal were calculated. Accordingly, male horses had significantly lager cervical spinal cord volume and cervical spinal cord-to-spinal canal volume ratio than those of female horses (P<0.05). Sex differences in the cervical spinal cord-to-spinal canal volume ratio gradually decreased until around 1,400 days of age. Younger male horses have narrower interspace between the cervical spinal cord and spinal canal than younger female horses, suggesting that an imbalanced cervical spinal cord and spinal canal growth is one of the causes of CVSM.     

Detection of anti-ebolavirus antibodies in Ghanaian pigs

Some filoviruses such as ebolaviruses and marburgviruses, cause hemorrhagic fever in humans and nonhuman primates. Pigs are suggested to play a potential role in the filovirus ecology. We investigated the seroprevalence of filovirus infection in pigs in Ghana. Using a viral glycoprotein (GP)-based enzyme-linked immunosorbent assay, we detected filovirus-specific immunoglobulin G antibodies in 5 of 139 samples. These positive sera showed specificities to four different filovirus species. Particularly, two of the positive sera reacted to GPs of two African ebolaviruses (i.e., Ebola virus and Taï Forest virus) in Western blotting. Our results suggest that these Ghanaian pigs were exposed to multiple filoviruses and emphasize the importance of continuous monitoring of filovirus infection in pig populations in West African countries.