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21.
Workers in poultry abattoirs may be frequently exposed to Campylobacter jejuni, which is a leading cause of bacterial food poisoning in Japan. The present study was conducted to measure the titers of IgG and IgA antibodies against C. jejuni among 104 female workers in a chicken processing plant in Miyazaki prefecture, Japan. Information regarding habitual ingestion of raw chicken meat and potential occupational risk factors was collected using a questionnaire. Acid extracts of four C. jejuni strains representing the genotypes most dominant in Miyazaki were used as antigens. The levels of both immunoglobulins measured by ELISA were not correlated with ingestion of edible raw chicken meat, the amount consumed in one sitting, or its frequency. Although age was correlated with antibody levels, the length of employment was not. Furthermore, the IgG and IgA levels in workers at the evisceration step were significantly higher than those at other locations in the plant. To identify the bacterial proteins recognized by the workers’ IgG and IgA antibodies, Western blotting followed by LC/MS was conducted. Flagellin was identified as the common protein recognized in the sera of workers for whom ELISA demonstrated both the highest and lowest antibody levels. We concluded that the titers of IgG and IgA against C. jejuni in workers at the processing plant had been increased by occupational exposure to Campylobacter, regardless of raw chicken meat ingestion.  相似文献   
22.
The time course of GnRH pulse generator activity and plasma concentrations of energy substrates and insulin were simultaneously observed in female goats during 4-day fasting and subsequent refeeding in the presence or absence of estrogen for a better understanding of the mechanism of energetic control of gonadotropin secretion in ruminants. The GnRH pulse generator activity was electrophysiologically assessed with the intervals of characteristic increases in multiple-unit activity (MUA volleys) in the mediobasal hypothalamus. In estradiol-treated ovariectomized (OVX+E2) goats, the MUA volley intervals increased as fasting progressed. Plasma concentrations of non-esterified fatty acid and ketone body increased, while those of acetic acid and insulin decreased during fasting. The MUA volley intervals and plasma concentrations of those metabolites and insulin were restored to pre-fasting levels after subsequent refeeding. In ovariectomized (OVX) goats, changes in plasma metabolites and insulin concentrations were similar to those in OVX+E2 goats, but the MUA volley intervals were not altered. The present results demonstrated that fasting suppressed GnRH pulse generator activity in an estrogen-dependent manner. Changes in plasma concentrations of energy substrates and insulin during fasting were associated with the GnRH pulse generator activity in the presence of estrogen, but not in the absence of the steroid in female goats.  相似文献   
23.
To assess the performance of boars derived by somatic cell cloning, we analyzed various aspects of their reproductive characteristics and the expression of two imprinted genes. Cloned boars (cloned Duroc × Jinhua) were analyzed for birth weight, growth rate, age at first ejaculation, semen characteristics and fertility, in comparison with naturally bred control boars of the same strain. The expression of imprinted genes was analyzed using the microsatellite marker SWC9 for the paternally expressed gene insulin‐like growth factor ‐2 (IGF2) and with single nucleotide polymorphisms (SNPs) for the gene maternally expressed 3 (MEG3). The cloned boars had high production of semen and were nearly equal in level of fertility to conventional pigs; they showed similar characteristics as naturally bred boars of the same strains. The expression of IGF2 was partially disturbed, but this disturbed expression was not linked to a change in developmental fate or reproductive performance. These results indicate that use of cloned boars could be highly effective for proliferation of pigs with desirable characteristics, preservation of genetic resources and risk reduction against epidemic diseases, such as foot‐and‐mouth disease, through storage of somatic cells as a precautionary measure for use in regenerating pig populations after a future pandemic.  相似文献   
24.
Feces were collected from two female and one male Siberian tigers, Panthera tigris altaica. Steroid hormones were extracted from lyophilized feces and quantified by enzyme immunoassay. The fecal contents of estradiol-17beta (E(2)) and testosterone in the females and male, respectively, changed markedly throughout the year. The fecal E(2) contents of females Nos. 179 and 238 increased at 26.4 +/- 8.0 and 28.0 +/- 14.2 day intervals, respectively. However, the fecal contents of progesterone (P(4)) in the female kept alone did not change. In contrast, the other female, which was kept with a male, had increased fecal P(4) contents after copulation. The fecal progesterone levels of the pregnant female remained high during her 106-day pregnancy.  相似文献   
25.
The present study was conducted to examine the effects of three tannin relatives (tannic acid, TA; gallic acid, GA; and ellagic acid, EA) on antihyaluronidase and reactive oxygen species (ROS) scavenging activity, in vitro fertilization (IVF) parameters, and the acrosome reaction (AR) induced by sperm-zona interaction. Among the three tannin relatives, TA and EA showed the strongest potency for blocking the hyaluronidase activity of boar sperm, with concentration-dependent inhibition over the range of 2-10 microg/ml. In contrast, ROSs were effectively scavenged by TA and GA, but not EA. When cumulus-free oocytes were inseminated in IVF medium containing 5 microg/ml of the tannin relatives, polyspermy was significantly reduced by TA and EA (32 and 29%, respectively) compared with oocytes treated with or without GA (51 and 69%, respectively) under conditions that maintained a high sperm penetration rate (P<0.05). Interestingly, induction of the AR by treatment of preincubated sperm with progesterone was blocked by TA and GA as a result of their higher levels of ROS scavenging activity, while EA, which possessed weak ROS scavenging activity, did not disturb induction of the AR with progesterone. However, the incidence of AR induced by sperm-zona interaction was significantly decreased by the strong antihyaluronidase actions of TA and EA compared with that in the absence of these compounds. Treatment with the compounds caused neither a protective proteolytic modification of the zona pellucida matrix before fertilization nor a reduction in acrosomal proteolytic activity or the number of zona-bound sperm. These findings suggest that the antihyaluronidase action of EA effectively prevents polyspermy by suppression of AR functionality induced by sperm-zona interaction and that hyaluronidase intervention is therefore required during porcine IVF.  相似文献   
26.
Androgen induces production of male effect pheromone in female goats   总被引:1,自引:0,他引:1  
Previously we showed that the primer pheromone responsible for the "male effect" was produced in specific skin regions of castrated male goats by androgen treatments. In the present study, we examined whether androgen can also induce production of the male effect pheromone in female goats. Capsules containing dihydrotestosterone (DHT) or testosterone (T) were subcutaneously implanted into six ovariectomized (OVX) goats for 28 days. Small skin samples were collected from the head and rump regions, and the pheromone activity of their ether extracts was examined using a bioassay that monitors the electrophysiological manifestation of the hypothalamic gonadotropin-releasing hormone pulse generator as multiple-unit activity. Behaviors of OVX goats towards ovary-intact estrous goats were also examined before and at the end of DHT or T treatment. Before androgen treatment, neither the head nor rump skin samples in OVX goats showed pheromone activity. DHT treatment induced pheromone activity in the head skin sample of six OVX goats and in the rump skin sample of two OVX goats. Similar results were obtained by T treatment. In addition, OVX goats treated with T showed masculine-type sexual behaviors such as courtship and mounting behaviors towards the estrous goats. These results demonstrate that androgen is capable of inducing primer pheromone activity in the female and suggest that the synthesis pathway of the male effect pheromone exists in both sexes in the goat.  相似文献   
27.
28.
六月龄去势公猪表现昏睡、食欲不振、站立困难。尸检发现脾脏边缘呈多重出血灶。从脾脏、肾脏、肌肉和肝脏中分离出革兰氏阳性杆菌,对分离株(TO16177)的16S rDNA基因序列比较分析发现,其可能与未发表过的隐秘杆菌属HJ57-14E菌株(登记号:gi18873551)(比较675bp个碱基,相似性达99.7%)为同一个属。脾脏组织切片的组织学检查发现呈广泛性坏死和炎症,其中革兰氏阳性杆菌显而易见。肝脏中可见多病灶的坏死斑。免疫组织化学检测发现,分离株与抗化脓性隐秘杆菌属(Arcanobacterium pyogenes)和内氏放线菌(Actinomyces naeslundii)的多克隆抗体具有交叉反应,且与后者的交叉反应更强烈。相似的反应也见于扁桃体的化脓灶中分离株,偶尔也见于脾脏和淋巴结中的分离株。本研究结果表明,这种未公开发布的隐秘杆菌属的细菌会引起生长肥育猪多器官功能衰竭,而后继发急性出血性坏死性脾炎。  相似文献   
29.
Although the sea otter (Enhydra lutris) is a complete aquatic species, spending its entire life in the ocean, it has been considered morphologically to be a semi-aquatic animal. This study aimed to clarify the unique hindlimb morphology and functional adaptations of E. lutris in comparison to other Mustelidae species. We compared muscle mass and bone measurements of five Mustelidae species: the sea otter, Eurasian river otter (Lutra lutra), American mink (Neovison vison), Japanese weasel (Mustela itatsi) and Siberian weasel (M. sibirica). In comparison with the other 4 species, E. lutris possessed significantly larger gluteus, popliteus and peroneus muscles, but smaller adductor and ischiopubic muscles. The popliteus muscle may act as a medial rotator of the crus, and the peroneus muscle may act as an abductor of the fifth toe and/or the pronator of the foot. The bundles of the gluteus superficialis muscle of E. lutris were fused with those of the tensor fasciae latae muscle and gluteofemoralis muscles, and they may play a role in femur abduction. These results suggest that E. lutris uses the abducted femur, medially rotated crus, eversion of the ankle and abducted fifth digit or extended interdigital web as a powerful propulsion generator. Therefore, we conclude that E. lutris is a complete aquatic animal, possessing differences in the proportions of the hindlimb muscles compared with those in other semi-aquatic and terrestrial mustelids.  相似文献   
30.
The association between blood calcium levels and electrocardiographic variables was compared in 137 normal parturient and 36 peripartum recumbent Holstein cows to determine whether hypocalcemia in peripartum dairy cows can be rapidly diagnosed using electrocardiograph. Inverse of STc (ST peak interval/SS interval0.5) and blood ionized calcium or serum calcium concentrations were strongly correlated, and both correlation coefficients were 0.81 (P<0.001). The 95% prediction interval indicated that cows with STc >0.385 ± 0.001 sec are very likely to be hypocalcemic (blood ionized or serum calcium concentrations of <0.9 mmol/l or <7.5 mg/dl, respectively). These findings indicate that hypocalcemia in parturient cows can be non-invasively estimated using the STc.  相似文献   
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