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1.
Mandibular pyogranulomatous osteomyelitis was diagnosed in a female Sannen goat. The doe presented for difficulty prehending and chewing food. The left mandible was swollen and firm on palpation. Radiographs revealed changes consistent with osteomyelitis of the affected mandible. Arcanobacterium pyogenes was isolated from aspirates of swollen mandible. Despite antimicrobial therapy, the goat died. Histopathological findings were consistent with pyogranulomatous disease of the affected mandible. The histopathological findings were similar to those reported for actinomycosis, caused by Actinomyces bovis. Mandibular osteomyelitis is a common condition in cattle and very rare in goat.  相似文献   
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Brood fish nutrition is an important factor susceptible to affect not only fecundity and gametogenesis but also gamete quality. In this study, we investigated the effects of altering dietary vegetable fatty acid content on semen quality (i.e. motility, density and seminal plasma composition), fertilizing ability and also blood testosterone (T) concentration in rainbow trout (Oncorhynchus mykiss). Fish were fed a commercial diet and ten formulated diets with similar proximate compositions but different levels of vegetable fatty acids (highly unsaturated fatty acids (HUFA): monounsaturated fatty acids (MUFA); HUFA: polyunsaturated fatty acids (PUFA); and HUFA: saturated fatty acids (SFA) ratios). Fish fed with HUFA: MUFA = 0.0 and HUFA: SFA = 0.25 ratios had the highest semen motility percentage and duration. However, the highest semen concentration and semenatocrit were observed in HUFA: SFA = 0.0 and HUFA: PUFA = 0.37 ratios. There was a significant difference in terms of K+ ion among diets supplemented with HUFA: PUFA = 0.0, HUFA: PUFA = 0.37 and HUFA: MUFA = 0.16 ratios (< .05). Furthermore, Na+ ion showed significant difference between control group and diet supplemented with HUFA: PUFA = 0.0 (< .05). Among the biochemical parameters, total protein showed a significant difference between HUFA: MUFA = 0.16 and HUFA: PUFA = 0.37 ratios (< .05). No significant differences in fertilization ability and blood T concentration were found among dietary treatments (> .05). In addition, the present data suggest that dietary fatty acid levels could affect semen quality but not fertilization ability in O. mykiss.  相似文献   
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Preservation of elite key lime (Citrus aurantifolia) genotypes using efficient micropropagation and regeneration protocols is very important for new breeding programmes. The objective of the present study was to develop an efficient protocol for micropropagation and maintenance of elite genotypes of key lime based on slow growth and starvation strategy. To do this, regenerated shoots were starved, and the growth was compromised via avoiding subcultures for 4, 8, 12 and 24 months. The numbers of responsive explants and adventitious shoots per each explant were evaluated in the presence of benzylaminopurine (BAP). The results showed that the 12- and 24-month starved explants treated with 1 mg/l BAP were able to produce four times more shoots than the control. In addition, the influences of horizontal or vertical layering explants over medium were evaluated. The results indicated that all horizontally layered explants significantly produced 25% adventitious shoots more than vertical explants, most likely owing to more contact with the surface medium. Finally, it could be concluded that application of slow growth, starvation strategy and also horizontally layering of the explants could efficiently enhance micropropagation and maintenance of threatened elite key lime genotypes with a low cost.  相似文献   
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OBJECTIVE: Evaluation of use of a supernumerary teat as a pedicle graft to repair experimental teat tip damage in cattle. STUDY DESIGN: Experimental study. ANIMALS: Mature, non-gravid hybrid cows with > or =1 supernumerary teat. METHODS: The main teat and adjacent supernumerary teat were examined for patency by ultrasound with a 8 MHz linear array transducer. The tip of the main teat was resected at the junction of cistern and canal. The supernumerary teat was partially resected semi-circumferentially at the cranial aspect of the base to maintain vascular supply and transplanted by end-to-end anastomosis. The pedicle of the supernumerary teat graft was amputated in stages starting at 14 days, again at 16 days and separated at 18 days. Reconstructed teat patency was evaluated at intervals by ultrasonography and confirmed at 50 days by histopathology. Repeated measures ANOVA was used to compare the measurements of luminal diameter between days; significance was set at P<.05. RESULTS: All reconstructed teats were patent. Decreased luminal diameters were detected at 25, 32, 39, and 46 days by ultrasonography. On histopathology, granulation and epithelial (mucosal) proliferation contributed to luminal reduction. CONCLUSIONS: In this experimental model of an acute damage to a teat tip, supernumerary teat grafting was successfully used to restore teat anatomy. CLINICAL RELEVANCE: Supernumerary teat pedicle grafting may be considered as a salvage technique for reconstruction of a damaged bovine teat in cows that have an adjacent patent supernumerary teat. Function of the reconstructed teat in a lactating cow remains unknown.  相似文献   
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The aim of this study was to determine the effect of parity on the first day of ultrasonic detection of embryo and its organs using 8 MHz frequency. For this purpose, six nulliparous heifers, five primiparous cows and six multiparous cows of the Holstein breed were selected and mated by a single bull from the herd. From day 16 after mating, cows and heifers were examined by ultrasonography thrice weekly for the day of first detection of the embryo and its organs. The mean of first-day detection in heifers, primiparous and multiparous cows was as follows, respectively: allantois on days 22.3, 23 and 25.8; embryo proper on days 21.8, 23 and 27; heartbeat of embryo on days 26.1, 26.6 and 31.1; amnion on days 31, 31 and 30.8; limb buds on days 29.5, 28.8 and 30.6; stomach (abomasum) on days 32.2, 38.6 and 36.8; spinal column on days 32.6, 33.4 and 37.3; placentomes on days 33.3, 37 and 35.3; eyes on days 35.1, 35.4 and 38.6 and lens on days 40, 41.4 and 44. Although the mean of first day observation of all structures in heifers tends to be earlier than in the other groups, statistically, allantois, the embryo proper and its heartbeat in heifers and primipara were visualized significantly earlier than in multiparous cows. However, there were no differences between heifers and primiparous cows.  相似文献   
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Elevated phosphate concentrations at Safaga and Quseir, Red Sea, Egyptian coast, wererelated to some ecological and nutritional aspects of the macro-alga Cystoseira myrica during1985. The results obtained were compared with those recorded for a non-polluted control site atGhardaqa. Chemical analysis of surface seawater samples revealed that the concentrations of dissolvedphosphate at Safaga and Quseir were 3 and 20 times as much as that at Ghardaqa, respectively.The standing crop of C. myrica showed two peaks in spring and autumn. Maximum biomass yield(491 g m-2) and number of individuals (127 m-2) of C. myrica were recorded in the spring at theGhardaqa site. Quseir C. myrica samples contained significantly higher protein-N, total-N andtotal-P values but lower carbohydrate values than the Safaga and Ghardaqa samples (LSD at 1%level). Tissue N:P molar ratios for C. myrica, Laurencia papillosa and Ulva lactuca collected fromGhardaqa ranged from 68-98, compared to 30-59 for the same species collected at thephosphorus polluted sites at Safaga and Quseir. The carbon levels and the C:N ratios of C. myricaexhibited no significant variations in the three studied sites. However, the C:P ratios of Ghardaqaplants were significantly higher than those of Safaga and Quseir.  相似文献   
8.
Constructed wetlands have been recognized as offering a removal treatment option for high concentrations removal of chemical and biological contaminants in domestic wastewater. The enteric protozoan parasite Cryptosporidium is considered one of the highly resistant to treatment and highly infectious organisms to humans and animals. Moreover, some species of Cryptosporidium are known to have a zoonotic nature. In this investigation a pilot scale for domestic wastewater treatment system was used, consisting of the following steps in series: (1) up-flow anaerobic sludge blanket (UASB) reactor, (2) free water surface (FWS) wetland unit, and (3) sub-surface flow (SSF) wetland unit. This treatment system was fed with domestic wastewater to assess its efficiency in removing Cryptosporidium oocysts. The obtained Cryptosporidium oocysts were detected and enumerated by two different staining techniques ‘acid fast trichrome (AFT) and modified Ziehl Neelsen (MZN) stains’. Polymerase chain reaction (PCR) technique was also used to detect Cryptosporidium DNA in wastewater samples. Results revealed that anaerobic treatment (using UASB reactor) could remove about 53.1% of Cryptosporidium oocysts present in raw wastewater. The in-series connection between the two wetland units allowed complete elimination of Cryptosporidium oocysts as the first (FWS) wetland unit removed 95.9% of the oocysts present in anaerobically treated wastewater and the remaining portion of oocysts was completely removed by the second (SSF) wetland unit. Cryptosporidium oocysts were detected in 95.8% of raw wastewater samples with a mean count of 43.8 oocysts/l when AFT stain was used while they were detected in only 87.5% of raw wastewater samples with a mean count of 35.6 oocysts/l when MZN stain was used. Polymerase chain reaction (PCR) technique was able to detect Cryptosporidium DNA in only 45.8% of raw wastewater samples. Positive PCR results were only achieved in wastewater samples containing 52 oocysts or more per liter.  相似文献   
9.
Triticeae γ-type seed prolamins have undergone many rounds of gene duplications during evolution. However, the population genetics of total Triticeae γ-prolamin genes has not been studied in an evolutionary perspective so far. Here, evolutionary pattern of γ-prolamin multigene family containing 557 sequences from wheat and closely related species (γ-gliadins), rye (γ-secalin) and barley (γ-hordeins) was investigated. Furthermore, Triticeae genomes were searched for low immuno-reactive celiac disease (CD) epitope contents in their γ-prolamins for the possibility of developing less immunogenic cultivars. Large numbers of haplotypes with segregating sites and mutations in γ-type seed prolamin multigene family were evident. Polymorphism analyses of both promoters and coding regions of species-specific γ-prolamins demonstrated no deviation from neutral theory. The sliding window revealed that most of the singleton polymorphic sites are resided in the variable R1 domain. Furthermore, the significant negative Tajima’s D and H tests’ values of each groups 1, 2, 3, and 8 showed a selective sweep for R and D genome duplication processes. The dN/dS ratio analysis revealed strong purifying selection acting upon duplication of the two ancestral branches, while the neutral selection among overall groups was observed. Our results support previously reported findings that the groups of 2, 3, 8 (D genome) and 10 (A genome) can potentially be recommended for selection approaches or genetic engineering of less immunogenic cereal grains. Furthermore, the results provide new insights on the evolutionary dynamics of γ-prolamin multigene family, polyploidy speciation and phylogeny of Triticeae species.  相似文献   
10.
Alpha-toxin is produced by all types of Clostridium perfringens. The genes encoding alpha-toxin from the available five types of Clostridium perfringens [A (chicken strain), A (rabbit strain), B, C and D] were PCR amplified using specific primers and the PCR products were examined on 1.5% (w/v) agarose gel and demonstrated the same bands comparable to the published alpha-toxin gene. Restriction enzyme analysis using two sets of enzymes (one set known to have recognition sites; Hinf1, EcoRV and Mse1 and the other set known to lack recognition sites Hind III, Pst1 and BamH1) were carried out. The first set of enzymes revealed the same cut specific for alpha-toxin gene. However, the second set of enzymes revealed no cut which is consistent to the published data. The PCR products of alpha-toxin gene from the five types were separately sequenced and aligned with all published alpha-toxin genes of Clostridium perfringens. Identities among all studied alpha-toxin gene sequences and with the published ones were nearly 96-98%. There are no any significant differences among these nucleotide sequences. It is concluded that alpha-toxin gene sequences among different types of Clostridium perfringens are similar and highly conserved.  相似文献   
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