The Effect of Exogenous Hormone Treatment on Spermiation in Rhynchocypris oxycephalus (Sauvage and Dabry)

For the evaluation of hormonal control of spermiation in fish, a method to quanify the spermiation response of mature Rhynchocypris oxycephalus (Sauvage and Dabry) to hormonal therapy is described. Spermatocrit was determined after 7 min centrifugation at 18,000 ± g and sperm density was estimated by a standard hemocytomer method. Sperm density can be predicted from spermatocrit since their relationship is linear as described by the regression equation, Y = 3.68X - 27.18 ( R ² = 0.82, N = 50). where Y is spermatocrit and × is sperm density. Milt production by mature R. oxycephalus was highest at 24 h after injection of 1,000 IU human chorionic gonadotropin (HCG) and 50 μg luteinizing hormone-releasing hormone analogue (LHRHa) per kg body weight. Increased milt production coincided with low spermatocrit and sperm density levels. These results demonstrate that spermiation in mature R. oxycephalus can be reliably evaluated by a spermatocrit method and that HCG and LHRHa are effective in stimulating of spermiation in this species.     

Radiographic interpretation of normal skeletal variations and pseudolesions in the equine foot.

Effective radiographic interpretation requires a veterinarian who is knowledgeable of equine limb anatomy and the various principles that affect the resulting image. The normal and its variations must be recognized and understood before the abnormal can be confidently identified as pathologic. Proper patient positioning and sound radiographic technique are mandatory if reliable diagnostic radiographs are to be produced. This review emphasizes equine foot radiographic variations of normal and pseudolesions that occur with commonly used radiographic views performed in equine practice.     

Radiographic examination of the equine foot

A complete radiographic examination of the equine foot consists of properly exposed, processed, and positioned radiographs. For radiographic interpretation, in addition to knowing radiographic signs of disease, a knowledge of normal radiographic anatomy and possible insignificant anatomic variations is necessary.     

Evaluation of host and bacterial gene modulation during Lawsonia intracellularis infection in immunocompetent C57BL/6 mouse model

BackgroundProliferative enteritis caused by Lawsonia intracellularis undermines the economic stability of the swine industry worldwide. The development of cost-effective animal models to study the pathophysiology of the disease will help develop strategies to counter this bacterium.ObjectivesThis study focused on establishing a model of gastrointestinal (GI) infection of L. intracellularis in C57BL/6 mice to evaluate the disease progression and lesions of proliferative enteropathy (PE) in murine GI tissue.MethodsWe assessed the murine mucosal and cell-mediated immune responses generated in response to inoculation with L. intracellularis.ResultsThe mice developed characteristic lesions of the disease and shed L. intracellularis in the feces following oral inoculation with 5 × l0⁷ bacteria. An increase in L. intracellularis 16s rRNA and groEL copies in the intestine of infected mice indicated intestinal dissemination of the bacteria. The C57BL/6 mice appeared capable of modulating humoral and cell-mediated immune responses to L. intracellularis infection. Notably, the expression of genes for the vitamin B12 receptor and for secreted and membrane-bound mucins were downregulated in L. intracellularis -infected mice. Furthermore, L. intracellularis colonization of the mouse intestine was confirmed by the immunohistochemistry and western blot analyses.ConclusionsThis is the first study demonstrating the contributions of bacterial chaperonin and host nutrient genes to PE using an immunocompetent mouse model. This mouse infection model may serve as a platform from which to study L. intracellularis infection and develop potential vaccination and therapeutic strategies to treat PE.     

Risk analysis of Bovine Spongiform Encephalopathy in Korea

The occurrence of Bovine Spongiform Encephalopathy (BSE, so called mad cow diseases) that was first identified in England in 1986 was considered as being limited to only European countries, including England. However, the outbreak in Asia as well as North America since 2001 has amplified the fear that there isn't any nation in the world that is a safe area. In order to assess the risk of BSE outbreak in each country, the Office International des Epizooties (OIE) and EU have respectively established criteria, where OIE has set 5 levels and EU has set 4 levels. The Scientific Steering Committee (SSC) of the European Commission conducted a Geographical BSE Risk(GBR) assessment for 64 nations, such as the United States, etc., as of April 29, 2003. However, as of July 1, 2005, the duty of GBR assessment is expected to be transferred to a newly established body called EFSA (European Food Safety Authority, located in Parma, Italy). As Korea has not undergone a GBR assessment up to now, this study analyzed the risk of BSE outbreak in Korea by reviewing BSE prevention measures, etc., that have been put in place. This study shall be a barometer for estimating the GBR assessment level of Korea.     

Canine adenovirus type 1 infection of a Eurasian river otter (Lutra lutra)

A 10-year-old female Eurasian river otter (Lutra lutra) died after prolonged anorexia and weight loss in the Seoul Grand Park Zoo, Seoul, Republic of Korea. On necropsy, the liver was found to be swollen and friable with 1 lobe enlarged and necrotic. The other organs showed no significant alterations except for mild atrophy of the right kidney. Microscopically, there was multifocal hepatic necrosis. The hepatocytes around the necrotic areas were swollen and contained large basophilic intranuclear inclusions. Periportal infiltration by plasma cells and lymphocytes was also evident. Transmission electron microscopy revealed characteristic hexagonal virus particles sized approximately 70 nm in diameter in the nuclei of the hepatocytes, which were consistent with an adenovirus. Polymerase chain reaction of the formalin-fixed, paraffin-embedded liver sections was used to determine whether the virus was either the canine adenovirus type 1 (CAV-1), canine adenovirus type 2 (CAV-2), or some other viral agent. The results of these tests showed that the virus was CAV-1. To our knowledge, this is the first report on a CAV-1 infection in an otter.     

Effects of road transportation on metabolic and immunological responses in Holstein heifers

This study examined the effects of road transportation on metabolic and immunological responses in dairy heifers. Twenty Holstein heifers in early pregnancy were divided into non‐transported (NT; n = 7) and transported (T; n = 13) groups. Blood was collected before transportation (BT), immediately after transportation for 100 km (T1) and 200 km (T2), and 24 h after transportation (AT). The T heifers had higher (P < 0.05) blood cortisol and non‐esterified fatty acid concentrations after T1 and T2 than did NT heifers. By contrast, the T heifers had lower (P < 0.05) serum triglyceride concentrations after T1 and T2 than had the NT heifers. The serum cortisol and triglyceride concentrations returned (P > 0.05) to the BT concentrations at 24 h AT in the T heifers. The granulocyte‐to‐lymphocyte ratio and the percentage of monocytes were higher (P < 0.05) after T2 in the T heifers than in the NT heifers, suggesting that transportation stress increased the numbers of innate immune cells. T heifers had higher (P < 0.01) plasma haptoglobin concentrations than NT heifers 24 h AT. In conclusion, transportation increased cortisol secretion and was correlated with increased metabolic responses and up‐regulation of peripheral innate immune cells in dairy heifers.