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61.
In the present study, 42 multiparous Holstein cows were used to investigate the relationship between fat accumulation in the liver and dry matter intake, milk yield and blood metabolites. Based on the percentage of fat in the liver cell at 2 weeks post‐parturition, the cows were classified into three groups. These groups were: (i) less than 10% of fat (normal group, n = 29); (ii) 10–20% of fat (mild group, n = 6); and (iii) more than 20% of fat (moderate group, n = 7). The bodyweight of the moderate group was high (771 kg) before calving. The sufficiency rates of total digestible nutrients (TDN) were remarkably decreased (approximately 65%) in early lactation. The milk fat yield and milk fat composition of the moderate group were higher (P < 0.05) than the other groups at 1 and 2 weeks post‐parturition. It was suggested that non‐esterified fatty acids (NEFA) mobilized from adipose tissues was directly used by the mammary gland for synthesis of milk fat. The percentage of bromsulfalein (BSP) retention of the moderate group was high (21.1%) at 30 min, and it showed that the BSP clearance function was significantly decreased. The concentrations of NEFA, β‐hydroxybutyric acid and glucose were appropriate indicators of energy status; however, aspartate aminotransferase, γ‐glutamyl transpeptidase and total bilirubin were not sensitive indicators of a moderate fatty liver. Thus, high‐yielding cows that calve in an overweight condition are more likely to develop excessive fat accumulation in the liver because of great mobilization from adipose tissues post‐parturition. In cows with a moderately fatty liver, a decrease in TDN sufficiency rates, an increase of milk fat yield and a reduction of liver function were observed in early lactation. The increase of serum NEFA and milk fat composition resulting from mobilization of adipose tissues helped to diagnose moderate fatty liver.  相似文献   
62.
The major organs and tissues of 24 broiler chickens (70 or 71 days old) suspected of spindle-cell proliferative disease (SPD) because of showing the tumorous lesions distributed throughout the body at meat inspection were collected for histopathological and immunohistochemical examination. Macroscopically, liver, spleen and cecal tonsil showed severe enlargement and white nodules or plaques were observed in the liver, spleen, kidney, intestine and bone marrow of the femur. All chickens were diagnosed with SPD based on the histopathological examination. The lesions of SPD were observed in the liver, spleen, kidney, heart, lung, pancreas, proventriculus, gizzard, duodenum, jejunum, ileum, rectum, cecal tonsil, bursa of Fabricius, bone marrow of the femur and skin. Hemangioma was observed in the lung of 1 bird. Eight 1-day-old specific pathogen-free chicks were inoculated intraperitoneally with 0.25 ml of a 20% homogenate of the affected spleens of three naturally occurring cases. One inoculated bird, necropsied at 10 weeks of age, macroscopically had a white nodule in the kidney and histopathologically had spindle-cell proliferative lesions, a pattern similar to that seen in the naturally occurring cases, in the liver, spleen, kidney, heart, lung, pancreas, proventriculus, duodenum, cecal tonsil and bone marrow of the femur, and was diagnosed with SPD. Immunohistochemically, significant positive reactions with a rabbit antiserum against avian leukosis virus antigens were detected in all spindle cells in the proliferative lesions of all examined SPD cases and in tumor cells of the hemangioma of a field case.  相似文献   
63.
It is known that physical disruption of cell contacts induces apoptosis of thymocytes. When thymocytes from LEC and WKAH rats were incubated in vitro at 37 degrees C for 0-6 hr and then the proportion of apoptotic cells was determined using a flow cytometer, it was found that the percentages of apoptotic thymocytes from both LEC and WKAH rats increased with incubation time and that the proportion of apoptotic cells from LEC rats was significantly higher than that from WKAH rats at each incubation time. The fact that cycloheximide, an inhibitor of protein synthesis, did not show significant inhibitory effects on induction of apoptosis of thymocytes indicates that induction of apoptosis during in vitro cultivation did not require de novo protein synthesis. When thymocytes from LEC and WKAH rats were X-irradiated in vitro at 4 and 8 Gy, the percentages of radiation-induced apoptotic cells increased with post-incubation time after X-irradiation in both LEC and WKAH rat thymocytes and the proportions of apoptotic cells from LEC rats were significantly higher than those from WKAH rat cells at 2 and 4 hr post-incubation after X-irradiation. When thymocytes from LEC and WKAH rats were X-irradiated in the presence of cycloheximide, the induction of apoptosis was substantially inhibited, indicating that radiation-induced apoptosis of thymocytes from LEC and WKAH rats required de novo protein synthesis. The present results showed high sensitivities of thymocytes of LEC rats to induction of apoptosis during in vitro cultivation and by X-irradiation.  相似文献   
64.
Soil types and fertilizer regimes were evaluated on growth, yield, and quality of Amaranthus tricolor lines, IB (India Bengal), TW (Taiwan), BB (Bangladesh B), and BC (Bangladesh C) in developing management practices in Okinawa. Growth and yield of all amaranth lines were higher in gray soil (pH 8.4) than in dark red soil (pH 6.6) and red soil (pH 5.4). The combined NPK fertilizer resulted in highest growth parameters and yield of amaranths in all soils. Nitrogen fertilizer alone did not affect growth parameters and yield of amaranths in dark red and red soils. Growth parameters and yield increased similarly with the 30, 40, and 50 g m?2 of NPK fertilizer in BB line, and with the 20, 30, 40, and 50 g m?2 in BC line. Agronomic efficiency of NPK fertilizer at 50 g m?2 was not prominent on the amaranths, compared to the fertilizer at 40 g m?2. Amaranth lines had higher Na in dark red and red soils, while K and Mg in gray soil, Ca in gray and red soils, and Fe in dark red soil. The NPK fertilizer resulted in higher Na, Ca, Mg, and P in BB line in glasshouse. These minerals in BB line were not clearly affected, but in BC line were lower with NPK fertilizer at 20–50 g m?2 in field. These studies indicate that gray soil is best for amaranth cultivation and combined NPK fertilizer at 20–40 g m?2 is effective in gray soil in Okinawa for higher yield and minerals of amaranth.  相似文献   
65.
Synaptic inputs on dendrites are nonlinearly converted to action potential outputs, yet the spatiotemporal patterns of dendritic activation remain to be elucidated at single-synapse resolution. In rodents, we optically imaged synaptic activities from hundreds of dendritic spines in hippocampal and neocortical pyramidal neurons ex vivo and in vivo. Adjacent spines were frequently synchronized in spontaneously active networks, thereby forming dendritic foci that received locally convergent inputs from presynaptic cell assemblies. This precise subcellular geometry manifested itself during N-methyl-D-aspartate receptor-dependent circuit remodeling. Thus, clustered synaptic plasticity is innately programmed to compartmentalize correlated inputs along dendrites and may reify nonlinear synaptic integration.  相似文献   
66.
Contagious equine metritis (CEM), a contagious venereal disease of horses, invaded Japan in 1980 and spread in the Thoroughbred population of the Hidaka-Iburi district of Hokkaido. To eradicate CEM, we ran a program aimed at detecting Taylorella equigenitalis, the causal agent, in carrier horses by using the PCR test, followed by culling or treatment. In 2001, the first year of the program, 12,356 Thoroughbred racing stallions and mares were tested and 11 carriers were found. Four, two, one, and one carrier mares were detected in 2002, 2003, 2004, and 2005, respectively, by application of the program at the same scale as in 2001. No PCR-positive horses were found from 2006 to 2010. These results strongly suggest that CEM was eradicated from Japan by 2010.  相似文献   
67.
Subclinical infection of chicken anemia virus (CAV) at 4 to 6 weeks of age, after maternal antibodies have waned, is implicated in several field problems in broiler flocks. In order to understand the pathogenesis of subclinical infection with CAV, an immunopathological study of CAV-inoculated 4-week-old SPF chickens was performed. Sixty 4-week-old SPF chickens were equally divided into CAV and control groups. The CAV group was inoculated intramuscularly with the MSB1-TK5803 strain of CAV. Neither mortality nor anemia was detected in the CAV and control groups. In the CAV group, no signs were observed, except that some chickens were grossly smaller compared with the control group. Sporadic thymus lobes appeared to be reddening and atrophied. Within the first two weeks p.i. of CAV, there was a mild to moderate depletion of lymphocytes in the thymus cortex and spleen in some chickens. Moreover, lymphoid depletion of the bursa of Fabricius, proventriculus and cecal tonsils was observed. Hyperplastic lymphoid foci were observed in the liver, lungs, kidneys and heart at the 4th week p.i. of CAV. Immunohistochemically, a moderate lymphoid depletion of CD4(+)and CD8(+) T cells in the thymus cortex and spleen was observed in some chickens within two weeks p.i. of CAV. CAV inclusions and antigens were detected infrequently in the thymus cortex and spleen. It could be concluded that the immunosuppression in subclinical infection with CAV occurs as a result of reduction of cellular immunity.  相似文献   
68.
We examined the relations between plasma insulin-like growth factor (IGF) -I concentrations during treatment with CIDR-based or Ovsynch protocol for timed AI and conception and plasma steroid concentrations in early postpartum Japanese Black beef cows. Cows in the control group (Ovsynch; n = 21) underwent Ovsynch protocol (GnRH analogue on Day 0, PGF(2alpha) analogue on Day 7, and GnRH analogue on Day 9), with AI on Day 10, approximately 20 h after the second GnRH treatment. Cows in the Ovsynch+CIDR group (n = 22) received Ovsynch protocol plus a CIDR for 7 days (starting on Day 0). Cows in the further treatment group (EB+CIDR+GnRH; n = 22) received 2 mg of estradiol benzoate (EB) on Day 0 in lieu of the first GnRH treatment, followed by the same treatment as in the Ovsynch+CIDR protocol. Plasma IGF-I concentrations were determined on Days -7, 0, 7, 9 and 17. Conception rates were improved in the CIDR-combined groups (both CIDR-treated groups were combined) relative to Ovsynch group (P < 0.05) for cows with low IGF-I concentrations (<1,000 ng/ml) on Days -7, 0, and 7, but improved conception rate produced by the CIDR-based protocols did not occur in cows with a high IGF-I concentration (> or =1,000 ng/ml). Plasma estradiol-17beta concentrations increased from Day 0 to 7 (P < 0.05) and were unchanged from Day 7 to 9 in the Ovsynch group with low IGF-I concentrations on Day 0, while they were unchanged from Day 0 to 7 and increased from Day 7 to 9 (P < 0.05) in the Ovsynch group with high IGF-I concentrations on Day 0 and in the CIDR-combined group. Plasma progesterone concentrations in the Ovsynch group with low IGF-I concentrations on Day 0 were higher on Day 14 than in the Ovsynch group with high IGF-I concentrations on Day 0 and in the CIDR-combined group (P < 0.05). In conclusion, CIDR-based protocols may improve conception relative to Ovsynch in early postpartum beef cows with lower plasma IGF-I concentrations at the start of the protocols. This improvement is probably due to prevention of premature increases of estradiol-17beta and progesterone concentrations, which occurred in cows with low IGF-I concentrations treated with Ovsynch, by the CIDR treatment.  相似文献   
69.
We compared synchronization and pregnancy rates, and the increase in blood progesterone concentrations during luteal development, between (1) Ovsynch plus an intravaginal controlled internal drug release (CIDR) device protocol followed by timed embryo transfer (timed ET), and (2) a conventional estrus synchronization method using PGF(2 alpha) and ET in suckled postpartum Japanese Black beef cows. Cows in the PGF group (n=18) received a PGF(2 alpha) analogue when a CL was first palpated per rectum at 10-d intervals after 1 to 2 month postpartum. Cows (n=11), which showed estrus (Day 0) within 5 d of the PGF(2 alpha), and had a CL on Day 7, received ET. Cows in the Ovsynch+CIDR group (n=19) underwent the Ovsynch protocol plus a CIDR for 7 d (GnRH analogue and CIDR on Day-9, PGF(2alpha) analogue with CIDR removal on Day-2, and GnRH analogue on Day 0), with ET on Day 7. The ovulation synchronization (100%) and embryo transfer (100%) rates in the Ovsynch+CIDR group were greater (P<0.01) than the estrus synchronization (66.7%) and the embryo transfer (61.1%) rates in the PGF group. The postpartum interval at ET in the Ovsynch+CIDR group (62.5 +/- 2.5 d) was shorter (P<0.01) than in the PGF group (74.9 +/- 3.9 d). The pregnancy rate in the Ovsynch+CIDR group (57.9%) did not differ significantly from that in the PGF group (50.0%). Plasma progesterone concentrations were not significantly different in the two groups on Days 0, 1, 2, 5, 7, 14 and 21. In summary, higher synchronization and transfer rates, and shorter postpartum interval to ET, can be achieved with timed ET following the Ovsynch plus CIDR protocol than after estrus with the single PGF(2 alpha) treatment followed by ET in suckled postpartum recipient beef cows. Pregnancy rates were similar. Also, the increase in blood progesterone concentrations during luteal development following ovulation synchronized by the Ovsynch plus CIDR protocol was similar to that after estrus induced by the PGF(2 alpha) treatment.  相似文献   
70.
A microplate agglutination test (MAT) was compared with the tube agglutinin test (TAT), a standard test for the diagnosis of Brucella canis, in terms of the sensitivity and specificity. The results showed that MAT was more sensitive, simpler to perform and easier to read the results than TAT. On top of that the MAT allows us to handle a larger number of samples at once. Using this method we conducted sero-surveillance of the prevalence of B. canis in dogs kept in an Animal Shelter located in Kanagawa Prefecture. Twelve of 485 (2.5%) showed seropositive against B. canis. These results indicate that B. canis infection in dogs is still occurring in Japan.  相似文献   
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