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151.
Soybean ( Glycine max ) cv. Harosoy 63 is resistant to race 1 and susceptible to race 9 of Phytophthora megasperma f. sp. glycinea (Pmg). In detached primary leaves inoculated with zoospores, growth of race 1 was completely suppressed 16 h after inoculation, while race 9 was unaffected. The amount of the phytoalexin glyceollin that accumulated, however, was not significantly different in either the incompatible or compatible interaction 16 h after inoculation. At the circumference of the inoculated area, a slight accumulation of phytoalexin was observed only in the incompatible interaction 20 h or more after inoculation. Tolerance of race 9 to the phytoalexin was significantly higher than that of race 1 when the phytoalexin was added to agar. Moreover, race 9 degraded glyceollin faster than race 1. On leaves inoculated at separate points with either race, the lesion associated with race 9 never colonized areas inoculated with race 1. These results suggest that factor(s) other than the accumulation of phytoalexin in soybean tissue might cause cessation of growth of Pmg.  相似文献   
152.
Due to the recent outbreak of avian influenza, transportation of frozen canine semen with egg yolk has been sharply restricted. Thus, there is urgent need to develop a novel egg yolk-free extender for freezing canine spermatozoa. In the present study, the effect of using skim milk/glucose (SG)-based extender without egg yolk on the motility and fertilizing capacity of canine spermatozoa frozen-thawed in the presence of glycerol was examined. There was a tendency for the proportion of motile spermatozoa exposed to SG-based extender for 3 h to be higher than that exposed for 1 h, but the difference was not significant. The motility and other viability parameters of canine spermatozoa after thawing were similar to those obtained with an egg yolk-based extender. When spermatozoa frozen with SG-based extender containing glycerol after 3 h exposure were transcervically inseminated into 2 recipient bitches, a total of 6 pups were obtained. These results suggest that a simple extender composed of skim milk, glucose and glycerol is useful for cryopreservation of canine spermatozoa, which may contribute to improved exchange of genetic material and efficient production of companion and working dogs, such as guide dogs for the blind.  相似文献   
153.
Manganese deficiency results in neurological and skeletal defects, together with ultrastructural disarrangement of the retina in rats. Wild birds show a range of Mn concentrations in their tissues, including the liver, raising the possibility of Mn-related disorders in the wild. Electroretinography (ERG) provides a useful noninvasive approach to evaluate visual function. This method is especially useful in birds, as objective analysis of them is very difficult, while they have well-developed vision. In this study, we carried out a convenient and reliable ERG recording using a contact lens electrode with a built-in light source (LED electrode) of Japanese quail (Coturnix coturnix japonica) fed a Mn-deficient diet. After 10 min light adaptation, single-flash and flicker cone responses were reproducibly recorded to cause an intensity-dependent increase in amplitude of both a-wave and b-wave in single-flash ERG. Mn-deficient feeding markedly decreased the Mn concentration in the liver by almost half in 3 to 6 weeks, followed by body weight loss in 13 to 15 weeks. Implicit time of a-wave and b-wave cone response by single-flash stimulation was significantly delayed in quail with a Mn depletion from 3 to 6 weeks. Every cone response of the Mn-deprived quail had a tendency to decrease amplitude. The ultrastructure of cone photoreceptor cells was disorganized by Mn deficiency, including changes in outer segment discs of photoreceptor cells. These results suggest the essential role of Mn in the integrity of the retinal function of birds.  相似文献   
154.
155.
Hyperglycemic clamp and hyperinsulinemic euglycemic clamp techniques were used to investigate effects of diet and cold exposure on insulin responsiveness to glucose and tissue responsiveness and sensitivity to insulin in adult rams. The sheep were fed a high-concentrate diet (80% concentrate and 20% roughage) and a high-roughage diet (20% concentrate and 80% roughage), both 70% above the ME requirement for maintenance, and were exposed to a thermoneutral environment (20 degrees C) and a cold environment (0 degrees C) for 2 wk. The estimated ME intake was greater (P < .01) for the high-concentrate diet than for the high-roughage diet. In the hyperglycemic clamp experiment, the ratio of the plasma insulin increment to the glucose infusion rate (insulin responsiveness to glucose) was lower during cold exposure than in the thermoneutral environment in sheep fed the high-concentrate diet but was unchanged in sheep fed the high-roughage diet. In the hyperinsulinemic euglycemic clamp experiment, the glucose infusion rate (tissue responsiveness to insulin) was higher (P < .01) for the high-concentrate diet than for the high-roughage diet, and it was also higher (P < .01) during cold exposure than in the thermoneutral environment, indicating that tissue responsiveness to insulin was intensified in sheep fed the high-concentrate diet during cold exposure associated with the higher energy intake. These results suggest that both reduced insulin responsiveness and enhanced tissue responsiveness to insulin in sheep exposed to cold were dependent on the type of diet.  相似文献   
156.
157.
Abe T  Nakamura K  Tojo T  Yuasa N 《Avian diseases》2001,45(1):234-239
Incidences of mortality without any clinical signs occurred in growing chicks in a broiler flock. Five 17-day-old dead broilers with gizzard erosions were investigated pathologically. Macroscopically, the gizzards were found to be dilated with bloody fluids. The koilin layer of the gizzards showed multifocal black patches (erosions). Histologically, there was necrosis of the koilin layer, degeneration and depletion of the gizzard glandular epithelium with intranuclear inclusion bodies, and hyperplasia of the macrophages in the lamina propria. An immunohistochemical analysis revealed intranuclear inclusion bodies in the degenerating gizzard glandular epithelial cells that stained positively for group I avian adenovirus antigen. Ultrastructurally, numerous viral particles (an average of 72 nm in diameter, from 63 to 88 nm) were in the intranuclear inclusions of glandular epithelium. This study suggests that the gizzard erosions may have been caused by group I avian adenovirus. In addition, the degeneration and depletion of gizzard glands secreting koilin substances, by adenovirus, may induce a reduction of koilin substances, which may then cause gizzard erosion (focal loss of the koilin layer).  相似文献   
158.
Two main trials and three preliminary experiments were conducted in order to examine adverse effects of excess lysine in 140- to 150-kg Holstein bull calves. The animals had been trained to maintain reflex closure of the reticular groove after weaning and were fed a corn and soybean meal diet. In Trial 1 (n = 30), administration via the reticular groove of 0 to 64 g/d of lysine as L-lysine monohydrochloride resulted in a linear decrease in DMI and N utilization efficiency, with notably lower values at 64 g/d, although ADG and gain/feed ratio were not affected. Plasma arginine and ornithine did not decrease but rather increased over that range. Free lysine but not free arginine was detected in urine. In addition, free ornithine was excreted into urine only when 64 g/d was administered. Unexpectedly, severe but transient diarrhea occurred when 64 g/d of lysine were administered. Preliminary experiments revealed that a single administration of more than 32 g of lysine as L-lysine monohydrochloride could result in diarrhea, and the diarrhea was proven to be due to the lysine itself and not to the HCl portion. In Trial 2 (n = 15), a single administration of 40 or 60 g of lysine as L-lysine monohydrochloride resulted in increased fecal excretion of free lysine and ornithine, especially the latter, although free arginine was not detected in feces. These results suggested that diarrhea could occur almost concurrently with an imbalance in calves when 64 g/d of lysine was administered. However, lysine did not antagonize arginine at that level or at lower levels. The remarkable increase in fecal ornithine may be somehow related to the development of diarrhea from excess lysine.  相似文献   
159.
Blastocystis hominis is a protozoan parasite found in humans. B. hominis-like organisms have been found in a variety of animals, but have been called Blastocystis sp. because the isolates from animals were indistinguishable from B. hominis morphologically. Recent molecular studies show that some isolates from animals have genetic similarity with B. hominis. However, it has been unclear whether the isolates from animals have zoonotic potential or not. In the present study, the SSUrDNA of 19 Blastocystis isolates from these animals was sequenced in its entirety, and the phylogenetic relationship among isolates from humans and animals was clarified using available nucleotide sequences of the same locus. Phylogenetic analysis showed that the 19 isolates analyzed in the present study could be classified into seven groups (I-VII): Group I consisted of the isolates from humans, primates, cattle, pigs and birds; Group II of the isolates from humans and primates; Group III of the isolates from humans, cattle and pigs; Group IV of the isolates from primates, birds and rodents; Group V of the isolates from cattle and pigs; Groups VI and VII of the isolates from humans and birds. These results indicate that many of the isolates harboring in animals have zoonotic potential, or have cross-transmissibility among heterogeneous hosts.  相似文献   
160.
Abstract: A male African pygmy hedgehog ( Atelerix albiventris ), estimated to be 3 years old, presented with exophthalmos and fixed abduction of the right eye. Radiographic examination revealed a retrobulbar tumor in the right orbital cavity. The mass was surgically resected but recurred 3 months later and the hedgehog died. There was no gross or microscopic evidence of salivary or lacrimal gland involvement of the tumor at surgery or at necropsy. The histopathologic, immunohistochemical, and ultrastructural findings were those of acinic cell carcinoma, the origin of which was unknown. This is the first known case of acinic cell carcinoma in an African hedgehog.  相似文献   
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