The proteins of the bovine erythrocyte membrane were analyzed by polyacrylamide gel electrophoresis in sodium dodecyl sulfate, and their relations to the slow sedimentation rate of bovine erythrocytes were investigated by treating the erythrocytes with trypsin. The erythrocyte sedimentation rates of bovine erythrocytes from Holstein and Korean native cattle were very slow compared with the human one (1/7 as slow as the human one) as reported previously. However, when human and Holstein erythrocytes were treated with trypsin (0.2 and 0.5 mg/ml) for 1 hour at 37deg C, their sedimentation rates were markedly accelerated while the sedimentation rate of Korean native cattle's erythrocytes were not affected. Although the general protein profiles of the bovine erythrocyte membranes were almost similar to that of human, bovine erythrocyte membranes showed one additional protein band called band Q in this study, which migrated electrophoretically to the mid-position between band 2 and band 3 in human erythrocyte membranes. Treatment of Holstein and human erythrocytes with trypsin caused a decrease or disappearance of the band Q from the erythrocyte membrane. Although the band Q in Korean native cattle's erythrocyte membrane was decreased by trypsin treatment of the erythrocytes, the magnitude of the decrement was not so pronounced as in the case of human and Holstein erythrocytes. The glycoprotein profiles of the bovine erythrocyte membranes revealed by periodic acid-Schiff stain showed a marked difference from that of human. The PAS-1 (glycophorin) and PAS-2 (sialoglycoprotein) present in human erythrocyte membrane were almost absent from the bovine erythrocyte membranes. Instead, the bovine erythrocyte membranes showed a strong PAS-positive band near the origin of the electrophorograms, which is named as PAS-B in this study

This study was carried out to determine suitable selection factors for recipients and embryos which could improve pregnancy rates following bovine embryo transfer. The experiment included 52 surgical transfers from February, 1985 through June, 1986 performed on Kyongbuk Breeding Center in southern Korea. The pregnancy rate was highest when recipients were in estrus within 6 hours before the donor to 12 hours after the donor (78.3 % versus 50 % for recipients in estrus earlier or later). Pregnancy rates were acceptable following culture under field conditions for up to 17 hours. More recipients over 15 months of age (76.1 %) remained pregnant than those under 15 months (66.7 %). Embryos transferred during the months from February to July resulted in higher pregnancy rates than those transferred during the remaining 6 months (77.3 % versus 57.1 %). Transferrable embryos were classified A (best) to C (worst); those graded A or B resulted in significantly higher pregnancy rates than those graded C (81.8 % and 73.3 % versus 25.0 %, p0.05). Pregnancy rates among recipients of the Korean native breed tended to be higher than among Holstein recipients (100 % versus 71.1 %). Similarly, when the embryo was transferred to the right uterine horn, pregnancy rates tended to be higher than when it was transferred to the left (81.3 % versus 65 %). Pregnancy rates did not differ according to the stage of development of the embryo; they were for morulae, tight morulae, blastocysts, and advanced blastocysts, respectively : 75.0 %, 66.7 %, 75.0 %, and 77.4 %

Morphological features of the vomeronasal organ of both Korean native cattle and Korean native goat were studied by gross, microscopic and histochemical examinations. Anatomical characteristics of the vomeronasal organ were similar in both Korean native cattle and Korean native goats. The vomeronasal organ is a tubular structure situated bilaterally at the base of the nasal septum, and enclosed by hyaline cartilage. Its lumen is semilunar to crescent in transverse sections. It joins with the incisive duct through narrow duct. The lumen of the vomeronasal organ is lined with sensory and respiratory epithelia. The distribution pattern of vomeronasal mucosal epithelia varied by the position. In the anterior portion joining with nasal cavity, the lumen is lined with only respiratory epithelium. In the middle portion, sensory epithelium appeared on the medial side, and respiratory epithelium on the lateral side. In the posterior, it is lined with sensory epithelium on the ventral side and lined with respiratory epithelium on the dorsal side. The vomeronasal gland composed of mucous and serous acini are distributed in the lamina propria under the respiratory epithelium, where venous sinuses are also well developed

To investigate the epidemiological trait of intestinal diseases of animals caused by thermophilic Campylobacter spp., isolation of etiological agent was carried out. Isolated Campylobacter spp. were biotyped, serotyped and the susceptibility of the isolates to antimicrobial agents were examined. Isolation rates of Campylobacter spp. from 649 fecal materials of 208 cattle, 300 pigs and 141 chickens were 25.5 %, 23.7 % and 38.3 %, respectively. The majority of the 130 isolates of C jejuni was classified as biotype I (50.6 %) and biotype II (34.6 %). Most of the 46 isolates of C coli were biotype I (71.7 %). Isolated C jejuni strains showed 14 different serotype, and serotype 4, 26, 36 were most frequent. Isolated C coli strains showed 5 different serotype and serotype 31 and 21 were relatively common. Isolated Campylobacter spp. were highly susceptible to nalidixic acid, amikacin, gentamycin, colistin and chlorampehnicol

To develop more specific and sensitive diagnostic methods for infectious bovine rhinotracheitis, 7-C-2 monoclonal antibody specific to polypeptides of infectious bovine rhinotracheitis virus (IBRV) was applied in indirect immunofluorescence antibody assay (IFA), indirect immunoperoxidase assay (IPA) and radial immunodiffusion enzyme assay (RIDEA). It was found that IBRV infected in MDBK cells could be detected as early as 8 hours post infection by IFA, and that IFA was more rapid and specific to identify IBRV antigen than IPA. The diagnostic efficacy of RIDEA and SN test was studied with 88 bovine sera. It was evident that RIDEA could eliminate the false positive reaction encountered in serum neutralization (SN)test, being more rapid and sensitive than the latter. Highly significant correlation coefficiency (r= 0.76, p0.01) was evaluated between the titers of sera and the diameters of RIDEA. Tracheal membranes and sera collected from 96 slaughtered cattle with lesions in respiratory organs were examined to detect IBRV antigen and antibody by IFA, RIDEA and SN test. It was presented that positive rates were 32.3 % in IFA, 20.8 % in RIDEA and 21.9 % in SN test, and that coincidence rate between RIDEA and SN test were 100 % in positive sera and 98.7 % in negative sera. In conclusion, it was assumed that application of monoclonal antibody could improve the diagnostic efficacy of IBR by enhancing sensitivity and specificity of IPA, IFA and RIDEA

Regional distribution and relative frequency of endocrine cells in ten portions of the gastrointestinal tract of the Korean native cattle were observed by immunocytochemical methods using specific antisera against chromogranin, serotonin, somatostatin, glucagon, bovine pancreatic polypeptide (BPP), motilin, gastric inhibitory polypetide (GIP), neurotensin, secretin, gastrin and substance P. In the abomasum, chromograin-, serotonin-, somatostatin-, motilin-, glucagon-, gastrin-, and substance P-immunoreactive cells were found. Chromogranin- and serotonin- and serotonin-immunoreactive cells were more numerous in the fundic region than pyloric region. Somatostatin- and gastrin- immunoreactive cells were numerous in the pyloric region than in the fundic region. In the large intestine, chromogranin-, serotonin- and BPP-immunoreactive cells were widely distributed and most numerous in the rectum. Somatostatin-, glucagon- and substance P-immunoreactive cells were rarely seen in the large intestine