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The stomach of the lesser mouse deer (Tragulus javanicus) was observed macroscopically. It consisted of only three compartments, rumen, reticulum and abomasum without omasum. The rumen was S-shaped with large ventral and caudoventral blind sacs and the reticulum was larger than the abomasum. Internally, the rumen was covered with numerous ruminal papillae even on the pillars and the ruminoreticular fold. These papillae were leaf- or tongue-like shaped and varied in size and density. The reticulum had honey-combed crests and the secondary crests were found rarely. The lips of the reticular groove were prominent and more developed in the aboral part than in the oral one. A sac-like transition zone, which had more prominent mucosal folds than had the floor of the reticular groove, was observed between the caudal end of the reticular groove and the abomasum. Mucosal folds of the abomasum were spiral, low but rather thick. These findings were discussed in view of comparison with other ruminants and of possible functional implications.  相似文献   
3.
Canine cationic trypsin was purified by salting-out, gel filtration and affinity chromatography. Purity was confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The molecular weight was ca. 28 kDa by SDS-PAGE.

Thirty hybridomas were obtained which produced mAb to canine cationic trypsin by the cell fusion technique. Twenty-two of these recognized cationic trypsin only, while eight hybridomas recognized both cationic and anionic trypsin. Several of the anti-canine cationic trypsin mAb were purified by salting-out and DEAE ion-change chromatography using ascites fluid of immunized BALB/c mice. The mAb proved to have very high specificity to canine cationic trypsin as shown by immunoblotting and it may be possible to use them to develop clinical assays.  相似文献   

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The relationship between donor cell cycle and the developmental ability of somatic cell nuclear transfer (SCNT) embryos has not fully been elucidated. Donor cells that are usually prepared by serum starvation or confluent-cell culture for SCNT represent a heterogeneous population that includes mainly G0 phase cells, other cells in different phases of the cell cycle and apoptotic cells. In this study, we compared the developmental ability of porcine SCNT embryos reconstructed from G0 phase cells (G0-SCNT embryos) and strictly synchronized-G1 phase cells (G1-SCNT embryos), and examined the developmental rates and timing of first DNA synthesis. The G0 phase cells were synchronized by confluent culture, and the G1 phase cells were prepared from actively dividing M phase cells. The G1-SCNT embryos showed a significantly higher (P<0.05) developmental rate to the blastocyst stage per cleaved embryo (59%) than the G0-SCNT embryos (43%). Moreover, initiation of first DNA synthesis and cleavage occurred significantly earlier in the G1-SCNT embryos than in the G0-SCNT embryos. Delay of initiation of first DNA synthesis in the SCNT embryos by aphidicolin resulted in decreased developmental rates to the blastocyst stage without any effect on cleavage rates. Our data demonstrates that synchronized-G1 phase cells can be used as donor cells for SCNT embryos and that earlier initiation of first DNA synthesis may be important for subsequent development of SCNT embryos. The SCNT system using G1-synchronized cells, in terms of their highly uniform and viable cell states, can be useful for studying the reprogramming processes and embryonic development of SCNT embryos.  相似文献   
6.
This study attempted to explain the mechanisms regulating boar fertility by examining seasonal changes in semen characteristics, the composition of seminal plasma and responsiveness of sperm acrosomes to Ca(2+) and the Ca(2+) ionophore A23187 (Ca(2+)/A23187). Sperm-rich and sperm-poor fractions were separately collected from 3 mature fertile Large White boars once a month over a one-year period. During the period of study, ambient temperature and relative humidity were recorded for within the stall in which the boars were kept and the semen characteristics, composition of the seminal plasma of sperm-rich fractions, and occurrence of the acrosome reaction in response to Ca(2+) (3 mM)/A23187 (0.3 microM) were examined. The highest mean maximum and minimum ambient temperatures were recorded in August-September, whereas the lowest mean maximum and minimum ambient temperatures were recorded in December and January, respectively. There was a moderate peak in relative humidity from July to October. The lowest percentages of motile spermatozoa and of spermatozoa with intact acrosomes and highest percentage of spermatozoa with abnormal morphology and strongest agglutination were seen in August-September. The total protein and albumin concentrations were lowest in August-September. Testosterone levels increased gradually as day length decreased after the summer solstice (June) and peaked in October-November. The percentage of acrosome reactions in response to Ca(2+)/A23187 was highest with the quickest response in August-September, as shown by the shortest time required for 50% of relative acrosome reactions. The farrowing rates were lowest in these same 2 months. These results suggest that seasonal infertility in Large White boars may be due, at least in part, to a combination of low motility, abnormal morphology including acrosomal abnormality, and early occurrence of the acrosome reaction in response to stimulus, possibly resulting from a decrease in acrosomal stabilizing proteins in the seminal plasma during summer. These changes may be modulated by heat/humidity stress and/or photoperiod-regulated testosterone.  相似文献   
7.
The pathogenicities of RacL11 and Kentucky D strains of equine herpesvirus 1 in the hamster infection model are different from those of Ab4p and the Japanese isolates. Virus genome restriction fragment length polymorphism analysis and sequence comparison of an intergenic region, glycoproteins and tegument genes showed higher conservation but with some strain-specific differences. These results indicate that point nucleotide differences in RacL11 and Kentucky D might be responsible for their pathogenicity in rodent models.  相似文献   
8.
Flavonoids ubiquitously exist in plants, vegetables, fruits, and teas. We evaluated the effect of dietary apigenin, one of the well-known flavonoids, on the immune system in C57BL/6N mice. Mice were fed experimental diets containing apigenin for 2 weeks. After the experimental period, there was no significant difference in body and organ weights between the control and the apigenin group. The total immunoglobulin (Ig) E levels in mice fed apigenin were significantly suppressed, whereas levels of IgG, IgM, and IgA were not affected. We also examined the effect of the apigenin diet on cytokine expression in mice sera using a cytokine array. The production of regulated upon activation normal T cell expressed and secreted (RANTES) and soluble tumor necrosis factor receptor I (sTNFRI) in mice sera was down-regulated by the apigenin diet. These results suggest that a diet containing apigenin can reduce serum IgE and inflammatory cytokines such as RANTES and sTNFRI in mice.  相似文献   
9.
The mucosal relief of the omasum in cattle, sheep and goats was examined by the naked eye, stereoscopic microscope and scanning electron microscope. The mucosal relief of the omasum showed wide variations both between and within these species. Omasal papillae on the laminae varied highly in shape, i. e. conical, rounded, claw-like, wart-like, finger-like etc. They decreased gradually in size from the oral to the aboral region of the omasal lamina. Ridge-like structures and linear arrangements of the papillae were also seen on the omasal laminae of cattle and sheep. Many grooves and folds were found on the lateral surface of the omasal papillae in adult cattle and on the inter-papillar surface of the laminae of all three species. The mucosal relief of the omasum in cattle seemed to be more well-developed than those of sheep and goats. Dietary effects on the omasal mucosa were also discussed.  相似文献   
10.
To establish a method to predict postpartum diseases using prepartum back fat thickness (BFT), the peripartum BFTs of 54 healthy multiparous cows before calving, which were diagnosed with postpartum displacement of the abomasum (DA), clinical ketosis or subclinical ketosis were compared with those of healthy cows from 8 weeks before the expected calving date to 8 weeks after calving. The peripartum BFTs of the cows with DA or clinical ketosis were significantly higher than those of healthy cows. The peripartum BFTs of the cows with subclinical ketosis were not significantly higher than those of the healthy cows.  相似文献   
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