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Detection of Minchinia occulta in samples of pearl oysters Pinctada maxima infected by Haplosporidium hinei 总被引：1，自引：1，他引：0
D Bearham ZB Spiers SR Raidal JB Jones PK Nicholls 《Australian veterinary journal》2009,87(11):430-437
Objective To determine if juvenile pearl oysters ( Pinctada maxima ) infected with Haplosporidium hinei are also infected with another haplosporidian parasite, Minchinia occulta .
Design Archived samples of pearl oysters infected with H. hinei were examined using polymerase chain reaction (PCR) assays and in situ hybridisation (ISH) to analyse and identify haplosporidians. A 144-bp and 220-bp region of Minchinia DNA were targeted by PCR and amplified DNA from formalin-fixed H. hinei -infected pearl oyster samples was sequenced. A 25-bp oligonucleotide probe targeting a variable section of the parasite's small subunit rRNA gene was used in ISH.
Results The results of DNA-based diagnostic assays supported each other. The sequences obtained by PCR were found to be almost identical to M. occulta from rock oysters and the ISH assay demonstrated infection with M. occulta in affected pearl oysters. ISH indicated a prevalence of infection of 26.7% in one of the previous outbreaks.
Conclusion Pearl oyster spat are susceptible to infection by a Minchinia parasite, most likely M. occulta , which was recently identified in rock oysters within the pearl-producing zones of Western Australia and is associated with mortalities of up to 80% in this species. The occurrence of haplosporidian co-infections in pearl oysters suggests the immunocompetence of juvenile oysters may be an important factor in preventing infection and therefore preventing mortalities such as those occurring in the recent outbreaks of pearl oyster oedema disease. 相似文献
Design Archived samples of pearl oysters infected with H. hinei were examined using polymerase chain reaction (PCR) assays and in situ hybridisation (ISH) to analyse and identify haplosporidians. A 144-bp and 220-bp region of Minchinia DNA were targeted by PCR and amplified DNA from formalin-fixed H. hinei -infected pearl oyster samples was sequenced. A 25-bp oligonucleotide probe targeting a variable section of the parasite's small subunit rRNA gene was used in ISH.
Results The results of DNA-based diagnostic assays supported each other. The sequences obtained by PCR were found to be almost identical to M. occulta from rock oysters and the ISH assay demonstrated infection with M. occulta in affected pearl oysters. ISH indicated a prevalence of infection of 26.7% in one of the previous outbreaks.
Conclusion Pearl oyster spat are susceptible to infection by a Minchinia parasite, most likely M. occulta , which was recently identified in rock oysters within the pearl-producing zones of Western Australia and is associated with mortalities of up to 80% in this species. The occurrence of haplosporidian co-infections in pearl oysters suggests the immunocompetence of juvenile oysters may be an important factor in preventing infection and therefore preventing mortalities such as those occurring in the recent outbreaks of pearl oyster oedema disease. 相似文献
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S Saraswat SD Kharche PK Rout R Pawaiya C Gangwar DK Swain R Kaushik 《Reproduction in domestic animals》2020,55(9):1080-1092
Estrogen and its receptors are essential for sexual development and reproduction. Oestrogen receptor alpha (ERα) is a nuclear receptor activated by the hormone oestrogen. In male, ERα is encoded by the gene ESR1 (oestrogen receptor1) responsible for better fertility. ESR1 is involved in the reabsorption of luminal fluid during the transit of spermatozoa from the testis to the head of the epididymis which is important for their survival and maturation during epididymal storage. The absence of ESR1 leads to reduced epididymal sperm content, reduced sperm motility and fertilizing ability. The present study was undertaken to investigate the expression and presence of ESR1 gene in fertile and low-fertile male goat breeds. We identified ESR1 gene through various molecular tools. Genotyping was carried out by high resonance melting analysis using Roche Light Cycler 480(LC-480) system and found three different genotypes. Genotypic frequency-AA (blue-0.67), BB(Red-0.2), AB(Green-0.08) with allele frequency A(0.71 and B (0.29). The predominance of this gene in head of epididymis in fertile bucks was confirmed by SDS-PAGE, Western blotting and immunohistochemistry. From the results, we corroborated that the present study provides a useful and effective way to predict male fertility in goat breeds, which in turn increases the percentage of fertility in flock leading to more number of offspring in a kidding season. 相似文献
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Objective To determine the clinical skills and areas of knowledge used by veterinarians in small animal practice during their first year after graduation and the degree of assistance and supervision they received while developing these skills. Design A postal survey was sent in December 1999 to 59 veterinarians who completed their training at Murdoch University in December 1998. Procedure The first part of the survey asked for information on veterinary work patterns since leaving university. The second part consisted of a list of diagnostic and therapeutic skills of varying complexity and the graduates were asked to indicate whether they had used these skills in practice and whether they had been assisted or supervised while doing them. The respondents were also asked if they had had the opportunity to practise these skills as undergraduates at university or during extramural experience. In the third part the areas of knowledge used in practice were assessed by analysis of a series of consecutive cases. Results Forty replies were received but since three graduates had done no small animal work the analysis of the skills section is based on 37 responses. Thirty graduates supplied information on 994 canine cases and 308 feline cases. The distribution of the mean work time was dogs and cats 69%, horses 13%, farm animals 11%, birds 3% and others 4%. Skills used by over 90% of graduates included general anaesthesia, examination of the tympanic membrane, taking and interpreting an abdominal radiograph, catheterising a male cat, fine needle aspiration of a mass, neutering dogs and cats, tooth scaling and extraction and treating an aural haematoma. The survey also identified the opportunities for undergraduates to practise some of these skills during extramural experience and the extent of assistance given to new graduates during their first year in practice. The areas of knowledge used in over 10% of the cases included vaccination, anaesthesia/sedation, skin/coat problems, general advice on pet health, neutering and musculoskeletal diseases. Conclusion Veterinarians, in their first year after graduation, use a wide range of complex diagnostic and therapeutic skills. Although many of these skills are acquired during the undergraduate training, a significant contribution is made by extramural practical work undertaken during the clinical years of the undergraduate course and in the first year following graduation. Practising veterinarians play an important role in providing opportunities and supervision for clinical training. 相似文献
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A national serological survey to verify Australia's freedom from porcine reproductive and respiratory syndrome 总被引：4，自引：0，他引：4
MG GARNER LJ GLEESON PK HOLYOAKE RM CANNON WJ DOUGHTY 《Australian veterinary journal》1997,75(8):596-600
Objective To provide serological data to support Australia's claim of freedom from porcine reproductive and respiratory syndrome.
Design A national serological survey was designed to provide 99% confidence of detecting at least one infected pig herd in Australia, assuming that at least 5% of herds would have been exposed to porcine reproductive and respiratory syndrome virus and that at least 25% of the 'finisher' pigs in these herds would have antibodies to the virus.
Procedure A two-stage testing regime was used. All samples were tested with a commercially available enzyme-linked immunosorbent assay. If assay reactions were found, all samples from the herd were to be tested using the indirect immunofluorescence antibody assay.
Results Of the 875 samples from 163 herds from all States in Australia, there was some evidence of reactivity in only four samples from four herds on the enzyme-linked immunosorbent assay. Further testing using the indirect immunofluorescence antibody assay according to the study protocol demonstrated that the reactions were not due to the presence of specific porcine reproductive and respiratory syndrome virus antibodies in the sera.
Conclusion The results of this study support the view that Australian pigs are free of porcine reproductive and respiratory syndrome virus. 相似文献
Design A national serological survey was designed to provide 99% confidence of detecting at least one infected pig herd in Australia, assuming that at least 5% of herds would have been exposed to porcine reproductive and respiratory syndrome virus and that at least 25% of the 'finisher' pigs in these herds would have antibodies to the virus.
Procedure A two-stage testing regime was used. All samples were tested with a commercially available enzyme-linked immunosorbent assay. If assay reactions were found, all samples from the herd were to be tested using the indirect immunofluorescence antibody assay.
Results Of the 875 samples from 163 herds from all States in Australia, there was some evidence of reactivity in only four samples from four herds on the enzyme-linked immunosorbent assay. Further testing using the indirect immunofluorescence antibody assay according to the study protocol demonstrated that the reactions were not due to the presence of specific porcine reproductive and respiratory syndrome virus antibodies in the sera.
Conclusion The results of this study support the view that Australian pigs are free of porcine reproductive and respiratory syndrome virus. 相似文献
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Triploblastic animals more than 1 billion years ago: trace fossil evidence from india 总被引：3，自引：0，他引：3
Some intriguing bedding plane features that were observed in the Mesoproterozoic Chorhat Sandstone are biological and can be interpreted as the burrows of wormlike undermat miners (that is, infaunal animals that excavated tunnels underneath microbial mats). These burrows suggest that triploblastic animals existed more than a billion years ago. They also suggest that the diversification of animal designs proceeded very slowly before the appearance of organisms with hard skeletons, which was probably the key event in the Cambrian evolutionary explosion, and before the ecological changes that accompanied that event. 相似文献
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Maturation Status, Protein Synthesis and Developmental Competence of Oocytes Derived from Lambs and Ewes 总被引：2，自引：0，他引：2
HPS Kochhar B Wu LHA Morris BC Buckrell JW Pollard PK Basrur & WA King 《Reproduction in domestic animals》2002,37(1):19-25
The efficacy of oocyte selection for in vitro embryo production depends on the abundance and diameter of follicles, cumulus layers around the oocytes and subsequent fertilization. Application of `ovum pick-up' technique allows us to utilize partially matured oocytes for embryo production even from juvenile subjects. To compare their developmental competence, oocytes derived from lambs and ewes and cultured in maturation medium for up to 26 h were assessed at 2 h intervals by confocal microscopy after chromatin and microtubulin-specific fluorochrome labelling. Lamb oocytes reached second meiotic metaphase (MII) at lower numbers at 24 h (60.0%) and 26 h (28.6%) whereas 85.7% of adult-derived oocytes attained MII status by 24 h of maturation. Radiolabelling of oocyte proteins revealed higher incorporation of [35 S-]-methionine and [35 S]-cysteine in adult-derived oocytes compared to lamb oocytes. Although the cleavage rate of lamb oocytes was similar to that of ewe oocytes, the proportion reaching blastocyst stage was significantly lower (p < 0.05) in the lamb-derived oocytes. However, blastocysts from both types of oocytes displayed similar cell lineage allocations to inner cell mass and trophectoderm. 相似文献