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991.
Serological analysis was performed to detect morbillivirus infection in Kuril harbor seals in Hokkaido, Japan. Serum samples were collected from the seals at Nosappu (231 sera), Akkeshi (16), and Erimo (75) between 1998 and 2005. Antibodies to phocine distemper virus (PDV) were detected by ELISA in seals from Nosappu and Erimo. Antibodies to PDV were found in 56% (5/9) of the sampled seals from Nosappu in 1998, versus only 5% (3/66) for 2003, 1% (1/79) for 2004, and 1% (1/77) for 2005. These suggest epidemic caused by the virus in or before 1998. As antibody-positive seals included juvenile seals in 2003 and 2005, sporadic infections of the virus are thought to have occurred in recent years. In Erimo, antibodies to PDV were found in 50% (14/28) of sampled seals in 2004, versus only 13% (1/8) for 1999, 7% (1/15) for 2003, and 0% (0/24) for 2005. These suggest sporadic infection by the virus before 2003 and the epizootic between after autumn in 2003, when samples of 2003 were collected, and 2004. Since antibodies to canine distemper virus (CDV) were detected in one adult seal from Nosappu in each year from 2003 to 2005, sporadic infections of the virus were suggested. There were no difference in incidence of seals with antibodies to the viruses between males and females and between juveniles and adults.  相似文献   
992.
993.
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is the most toxic of the halogenated dioxins and one of the most poisonous substances known to man. The major toxic effects of TCDD on reproduction are decreased fertility and diminished ability to maintain a pregnancy. Granulosa cells obtained from hormonally stimulated women participating in an in-vitro fertilization program were cultured with 3.1 femtomolar, 3.1 picomolar and 3.1 nanomolar TCDD. While inhibin B production was not altered, inhibin A production increased significantly after 4 hours of exposure to both nanomolar and micromolar TCDD concentrations. By 8 hours of exposure to these concentrations of dioxin, human luteinizing granulosa cells exhibited a pronounced increase in inhibin A, nearly quadrupling secretion from unexposed control cells. TCDD continued to increase inhibin A secretion at the picomolar concentration at 24 and 36 hours. It is conceivable that TCDD may act at the ovary to augment inhibin A secretion, thereby reducing FSH-stimulable estrogen secretion by granulosa cells.  相似文献   
994.
Friend murine leukemia virus A8 and PVC211 cause spongiform neurodegeneration in rat brains. Glutamate is an important neurotransmitter synthesized from alpha-ketoglutaric acid, an intermediate product of the citric acid cycle, and glutamine is synthesized from glutamate. To examine the brain metabolism of rats infected with neuropathogenic viruses, the amount of glutamate and glutamine in the brains of rats infected with A8, PVC211, and non-neuropathogenic 57 was measured using high performance liquid chromatography, and the (13)C-label incorporation into the C4 position of glutamate and glutamine from [1-(13)C] glucose was measured with (13)C nuclear magnetic resonance. In the cerebral hemisphere and region containing the brain stem and basal ganglia of rats infected with A8 and PVC211 at 8-9 weeks post-infection (wpi), the amount of glutamine was decreased compared with the 57-infected rats. The amount of glutamate was decreased in the cerebral hemisphere of the A8-infected rats and the region containing the brain stem and basal ganglia of PVC211-infected rats at 8-9 wpi. The amount of [4-(13)C] glutamine and [4-(13)C] glutamate in the cerebral hemisphere and region containing the brain stem and basal ganglia of rats infected with A8 and PVC211 at 8-9 wpi was equivalent to that of the 57-infected rats. These results suggest that in the brains of rats infected with neuropathogenic viruses, de novo synthesis of glutamate and glutamine is not decreased, but the ability to maintain quantitative levels of glutamate and glutamine is decreased compared with the brains of rats infected with non-neuropathogenic virus.  相似文献   
995.
The purpose of this study was to clarify whether weight change rate (WCR) is useful in evaluating herd health. Five herds (A, B, C, D, and E) were examined monthly for approximately 1 year to measure both WCR and BCS. WCR was calculated using the following equation: WCR (%) = (body weight of current month-body weight of the preceding month)/body weight of current month x 100. In addition, blood profiles were performed in each herd before and after calving. The incidence of periparturient diseases was higher in Herds A, B, and C compared with Herds D and E. Reproductive performance in Herds A and B was rather poor compared with Herds C, D, and E. There were significantly lower WCRs in Herd A compared with Herd C during the period of day -30 to day 30 after calving. According to the blood profiles, high levels of non-essential fatty acids (NEFA) were observed during the period of day -30 to -1 and high beta-hidroxybutyricacid (BHB) and low levels of glucose were observed at day 30 after calving in Herd A. A marked poor condition in Herd A during the peripaturient period was clearly expressed by low WCR in this experiment. WCR can express body condition of herds and is suggested to be a useful parameter in the determination of herd performance in field experiments.  相似文献   
996.
To compare the changes in the insulin reaction of Holstein dairy cows and Japanese Black cows (JB) during the periparturient period, the insulin resistance test in vivo and lymphocytes proliferation with insulin in vitro were performed. Ten healthy Holstein dairy cows (Holstein group) and 10 healthy JB cows (JB group) used in this study were observed on days 60, 40, and 20 before calving and days 7 and 20 after calving. In insulin resistance reaction in vivo and in vitro, a low insulin-stimulated glucose disposal rate and lymphocyte proliferation with insulin were observed in the Holstein group compared with the JB group during the experimental period. An analysis of the lymphocytes cultured with insulin showed that the percentage of CD4+CD45R- T cells in the Holstein group was significantly lower than that of the JB group before day 20. These findings indicate that T cells reaction to insulin in healthy periparturient Holstein cows is lower than that in Japanese Black.  相似文献   
997.
Killer whales were used to evaluate peripartum changes and interactions between body temperature and circulating progesterone concentration. Daily body temperature was measured between 0800 h and 0830 h before activity. Body temperature clearly increased during the first phase of pregnancy, and this was followed by a gradual decline until full term. The initial increase was paralleled by circulating levels of progesterone. A decrease in body temperature was first detected on day 5 (p < 0.01) before parturition, and body temperature decreased significantly every 2 days until delivery. Five days before delivery, body temperature was 0.3 C lower than the mean value during the pregnancy period, and the decrease was more marked on day 1 before delivery (0.8 C). Serum progesterone levels during pregnancy showed a general pattern of initial rapid elevation (increasing phase), followed by a gradual decline (decreasing phase) throughout the remainder of pregnancy. However, statistically significant correlations between body temperature and progesterone pattern were only found only during the increasing phase. These results suggest that monitoring body temperature variation can be considered valuable for predicting impending parturition in killer whales.  相似文献   
998.
Fecal survey of Eimeria oocysts and parasite eggs was conducted for 219 fecal samples of free-ranging Grus japonensis in Kushiro district in Hokkaido in April 2003. Positive rate and mean oocysts (or eggs) per gram in positive samples were 26% (57/219) and 8.8 (0.2-136) in oocysts of Eimeria reichenowi, 18.3% (40/219) and 320 (100-1,000) in trematode eggs, 0.1% (2/219) and 0.2 (0.2-0.3) in eggs of Nematoda A, and 4.1% (9/219) and 0.8 (0.2-3.6) in eggs of Nematoda B, respectively.  相似文献   
999.
A combination of increased harvest index and increased seed number per plant may improve wheat yield. We found an accession Triticum durum Desf. var. ramosoobscurum Jakubz. “Vetvistokoloskaya” R-107, whose plant height was short and spike was branched. To characterize R-107, we mapped the genes for semi-dwarfism and branched spike. Semi-dwarf gene Rht_R107 (Reduced height R107) from R-107 was allelic to Rht11 and Rht-B1b on chromosome 4BS. Rht_R107, as well as Rht11, was recessive and insensitive to gibberellic acid. Microsatellite mapping indicated that Rht_R107 was linked to Xwmc48 (1.2?cM) on chromosome 4BS, and Rht11 was also linked to Xgwm495 marker (19.4?cM) on chromosome 4BS. The locus responsible for branched spike in R-107 was mapped by genotyping three F2 populations using microsatellite markers. Phenotypic analysis revealed that branched spike was under control of a recessive allele at a single locus. The bh (branched head) locus was located on chromosome 2AS and the marker Xgwm425 flanked the bh gene proximally.  相似文献   
1000.
Subluxation of the proximal interphalangeal joint is a rare and little studied condition in horses. We describe the case of a 12-year-old mare with bilateral dorsal subluxation of the proximal interphalangeal joint of the hind feet. Tenectomy of the medial digital flexor was performed in both limbs, and the patient showed signs of recovery within 14 days. Goniometry of the proximal interphalangeal joints 10 months after surgery showed diminution of 5° for the proximal interphalangeal axis of the left hind limb. However, no change was found for the joint angle of the right limb. Even so, the patient's gait and radiographic results were normal, and clinical abnormalities such as joint clicking and swelling were no longer observed.  相似文献   
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