Growth,Reproductive Performance,Carcass Characteristics and Meat Quality in F1 and F2 Progenies of Somatic Cell-Cloned Pigs

The objective of this study was to examine the health and meat production of cloned sows and their progenies in order to demonstrate the application of somatic cell cloning to the pig industry. This study compared the growth, reproductive performance, carcass characteristics and meat quality of Landrace cloned sows, F1 progenies and F2 progenies. We measured their body weight, growth rate and feed conversion and performed a pathological analysis of their anatomy to detect abnormalities. Three of the five cloned pigs were used for a growth test. Cloned pigs grew normally and had characteristics similar to those of the control purebred Landrace pigs. Two cloned gilts were bred with a Landrace boar and used for a progeny test. F1 progenies had characteristics similar to those of the controls. Two of the F1 progeny gilts were bred with a Duroc or Large White boar and used for the progeny test. F2 progenies grew normally. There were no biological differences in growth, carcass characteristics and amino acid composition among cloned sows, F1 progenies, F2 progenies and conventional pigs. The cloned sows and F1 progenies showed normal reproductive performance. No specific abnormalities were observed by pathological analysis, with the exception of periarteritis in the F1 progenies. All pigs had a normal karyotype. These results demonstrate that cloned female pigs and their progenies have similar growth, reproductive performance and carcass quality characteristics and that somatic cell cloning could be a useful technique for conserving superior pig breeds in conventional meat production.     

Effect of replacing fishmeal with canola meal on growth and nutrient utilization in kuruma shrimp Marsupenaeus japonicus (Bate)

A feeding trial was conducted to assess the nutritional values of canola meal as a substitute for fishmeal in diets for kuruma shrimp using five isocaloric diets (190 kJ kg^?1) prepared by replacing 0%, 10%, 20%, 30% and 40% of fishmeal protein with canola meal protein in CM0, CM10, CM20, CM30 and CM40 diets respectively. Triplicate groups of juveniles (0.19 g) were fed the respective diets for 60 days in tanks. At the end of trial, weight gain (%) and specific growth rate (% day^?1) were not significantly (P > 0.05) different among shrimp fed CM0, CM10 and CM20 diets. However, growth was significantly (P < 0.05) decreased in shrimp fed CM30 and CM40 diets. As with growth performance, feed intake, feed conversion ratio and protein efficiency ratio were also decreased (P < 0.05) in CM30 and CM40 groups. Whole body dry matter, methionine and proline were significantly decreased with canola meal substitution levels. In general, retention efficiency of protein and indispensible amino acids were decreased as canola meal increased in diets. It may be concluded that 20% fishmeal protein can be successfully replaced with canola meal, while supplementation of amino acids or blending with complementary proteins could facilitate higher fishmeal replacements in kuruma shrimp diets.     

Effects of heat stress on the redox status in the oviduct and early embryonic development in mice

This study examined the association between redox status in the oviduct and early embryonic death in heat-stressed mice. In Experiment 1, non-pregnant mice were heat-stressed at 35 C with 60% relative humidity for 12, 24, or 36 h, and the maternal redox status was verified by measuring the levels of reactive oxygen species (ROS) and free radical scavenging activity (FRSA) in the oviduct, and thiobarbituric acid reactive substances (TBARS) and glutathione peroxidase (GSH-Px) activity in the liver. In Experiment 2, zygotes were collected from mice heat-stressed for 12 h on the day of pregnancy, and their developmental abilities were assessed in vitro, along with the intensity of DNA damage at the 2-cell stage. The TBARS value and GSH-Px activity in the liver, and ROS level in the oviduct were significantly higher in heat-stressed mice, and this increase appeared to depend on the duration of the heat stress. Maternal heat stress significantly reduced the percentage of zygotes that developed to the morula and blastocyst and the total cell number in the blastocyst. In addition, DNA damage at the 2-cell stage was significantly higher in maternally heat-stressed embryos. These results suggest that heat stress induces systemic changes in redox status in the maternal body, and the resultant increase in oxidative stress in the oviduct is possibly involved in heat stress-induced early embryonic death .     

Immunohistochemical analysis of expression patterns of tumor necrosis factor receptors on lymphoma cells in enzootic bovine leukosis

Tumor necrosis factor-alpha (TNF-alpha) has been reported to be associated with the progression of lymphoproliferative neoplastic diseases and retroviral infections. Hence we examined immunohistochemically the expression patterns of TNF-receptors (TNF-RI and RII) on lymphoma cells derived from the 29 cases of enzootic bovine leukosis (EBL). Lymphomas obtained in 29 animals with EBL were histopathologically classified into three types: diffuse mixed type (10 cases), diffuse large type (9 cases), and diffuse large cleaved type (10 cases). Immunohistochemically using a monoclonal antibody to a bovine lymphocyte surface antigen, the lymphomas were classified into three phenotypes: B-1a (CD5+/CD11b+), B-1b (CD5-/CD11b+) and B-2 (conventional B) (CD5-/CD11b-). Interestingly, the lymphoma cells in all animals expressed TNF-RII, but not TNF-RI. Although, in EBL, lymphoma cells of which the histopathological and immunological property differs has been formed, the expression patterns of TNF-Rs had the universality in all lymphoma cells. TNF-RII, which induces cell proliferation, was expressed but TNF-RI, which induces cell apoptosis was not expressed on all lymphoma cells, suggesting that TNF-Rs play an important role in the malignant proliferation of B cells and formation of lymphomas in EBL.     

Evaluation of fetal growth and estimation of fetal age based on skeletal growth in Hokkaido sika deer (Cervus nippon yesoensis Heude, 1884)

We investigated fetal development and the estimation of fetal age of 127 Hokkaido sika deer fetuses, categorizing them into three groups according to the nutritional condition of populations. The order and time of the appearance of ossification centers were clarified, and fetal age was determined based on bone length and the appearance of ossification centers. Then we observed the differences in fetal growth among three populations, and discussed the effect of poor nutrition on the fetal growth. The results suggest that fetal diaphysial length of the femur was affected very little by nutritional conditions, whereas conception dates were delayed and fetal weight was restricted as the nutritional condition became poorer. Although it is impossible to know the exact accurate fetal age in wild populations, it was possible to create a standard to estimate fetal age more precisely by the method described in this study. Both the bone length and the appearance of ossification centers are reliable indices to estimate fetal age precisely in measurements available from fetuses of unknown age, and can be applied to estimate the fetal age of other populations of sika deer, whereas estimation of fetal age based on weight is prone to great errors.     

Establishment and characterization of four canine melanoma cell lines

Four canine melanoma cell lines were established from the subcutaneous, oral gingival and mucosal melanoma tissues at the primary and metastatic sites. These cell lines were designated as CMeC-1, CMeC-2, KMeC and LMeC. The cells were spindles in shape, similar to that of primary tumor cells. The doubling times of these cells ranged from 34.1 +/- 5.61 to 57.9 +/- 3.28 hr and their chromosome number ranged from 46 to 80. When transplanted into nude mice, CMeC-1 and LMeC produced tumors, whereas CMeC-2 and KMeC did not. The morphology of the tissue formed by xenotransplantation of these cells was similar to their primary tumors.     

Hemophilia B in a crossbred Maltese dog

A crossbred Maltese dog, 6-year-old, male, was presented to us for examination due to coagulopathy. On examination of blood coagulation screening tests, activated partial thromboplastin time (APTT) was markedly prolonged (63.6 sec). Therefore, a defect in the intrinsic pathway of coagulation was suspected. An additional serum test was also examined and APTT was returned to within the normal range. Furthermore, factor IX coagulation activity was markedly low (2.3%). On the basis of these results, the dog was diagnosed with hemophilia B. The dog has since been presented to us because of hemorrhage problems again after 5, 10, and 16 months, but blood transfusions have maintained good control of its coagulopathy for more than two years.