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1.
In mid-September, 1 month before the insertion of intravaginal pessaries to induce sexual activity, blood samples were collected every 4 days from 16 ewe lambs aged 7 months, in order to determine the incidence of ovulations by measurement of plasma progesterone concentrations. It has been studied whether the response to a progestagen treatment of ewe lambs apparently close to puberty could be modified by the onset of the ovarian events preceding puberty. The effect of the presence or absence of ovulations prior to progestagen treatment on the potential reproductive performance (fertility, litter size and fecundity), embryo development [embryo quality and interferon-tau (IFNτ) secretion], luteal function (progesterone secretion in vitro ) and endometrial progesterone content was studied in seven ovulating (Ov+) and nine nonovulating ewe lambs (Ov−) on day 14 after mating. The best potential reproductive results were obtained with Ov+ animals, although these differences could not be initially attributed to either different progesterone secretion in vitro or concentration of endometrial progesterone. Irrespective of the experimental groups, secretion of progesterone by luteal tissue from ewe lambs with normal embryos was significantly greater (p<0.05) than that of animals with abnormal embryos or with no embryos. Normal embryos secreted a higher amount of IFN-τ than those embryos classified as abnormal (p<0.07). In conclusion, ewe lambs which exhibit luteal activity before puberty have the highest levels of reproductive performances after a progestagen treatment. Corpora lutea from ewe lambs with normal embryos had higher rates of progesterone secretion in vitro and their embryos had a higher IFN-τ production by the embryos, indicating greater capacity for subsequent development.  相似文献   
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Objective To establish the prevalence of intussusceptions involving the caecum in a population of horses admitted to a university hospital for colic. Design Retrospective clinical study Methods Medical records of all horses admitted to the Massey University Veterinary Teaching Hospital between 1991 and 2004 were examined for information of those horses diagnosed with an intussusception involving the caecum. Results A total of 135 horses were admitted for colic surgery during the study period and 61 horses had a diagnosis of ileocaecal (37), caecocaecal (5) or caecocolic intussusception (19) made either at surgery or necropsy. Of the horses with ileocaecal intussusception, 32 had an incomplete hand-sewn ileocaecostomy without reduction and 29 survived to discharge. All the horses with caecocaecal intussusceptions were diagnosed preoperatively via rectal examination and/or transabdominal ultrasound: 2 were euthanased at surgery and 3 survived to discharge. In the 19 horses with caecocolic intussusceptions, manually reduction at surgery was performed in 6 and 5 of them survived to discharge. A typhlectomy was performed via a colotomy in 6 horses, 3 of which survived to discharge. Conclusions The high prevalence of intussusceptions involving the caecum seen at this referral centre may indicate a higher prevalence in New Zealand than is reported elsewhere in the world. Clinical relevance Intussusceptions involving the caecum should be considered as a differential diagnosis in horses presenting with chronic low-grade colic. Transabdominal ultrasound is useful for identifying caecocaecal and caecocolic intussusceptions. Hand-sewn side-to-side incomplete ileocaecostomy is a quick, effective and safe method of surgical treatment of ileocaecal intussusceptions.  相似文献   
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This study reports on the epidemiology of Babesia gibsoni in American Pit Bull Terriers living in a region of western Victoria in southern Australia. Both American Pit Bull Terriers (n = 100) and other dog breeds (n = 51) were screened for B gibsoni using immunofluorescent antibody testing (IFAT) and/or polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). A questionnaire was also completed by each dog owner, ascertaining the husbandry and habits of the dogs sampled. Fourteen dogs were positive for B gibsoni using IFAT and/or PCR-RFLP and all were American Pit Bull Terriers. Dogs that were male and/or had been bitten by or were biters of other American Pit Bull Terriers were more likely to be B gibsoni positive, thus suggesting that blood-to-blood transmission contributes to the spread of this disease between dogs.  相似文献   
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DNA methylation is an epigenetic modification in which a methyl group is added usually to the fifth carbon position of a cytosine residue. Dysregulation of this process is an important molecular event which has been shown to be associated with neoplastic transformation and tumour progression in humans and mice. Features of methylation dysregulation in many different types of neoplasms include general genomic hypomethylation, focal hypermethylation, and altered expression of genes which encode a series of DNA (cytosine-5) methyltransferases. Interestingly, many types of neoplasia that are recognised in humans also develop spontaneously in the dog. By comparing the restriction patterns of MspI and HpaII, this study demonstrates that as in human, genomic hypomethylation is a feature of neoplastic cells in the majority of canine lymphoma cases and approximately one-third of canine leukemia cases confirming that dysregulation of the DNA methylating machinery is implicated in malignant transformation of lymphoid cells in some dogs.  相似文献   
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Mycobacterium fortuitum was isolated in a sample of bronchial fluid collected by transtracheal aspiration from a 1-year-old Corgi dog with a productive cough of 10 days' duration and with radiographic and cytological features of acute suppurative bronchopneumonia. The dog responded favourably to intravenous gentamicin and cephalexin for three days and a six week course of oral ciprofloxacin. Saprophytic mycobacterial pneumonia should be considered in cases of severe pulmonary consolidation in young dogs.  相似文献   
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A 4-year-old, entire female, English Cocker Spaniel was presented for treatment of lymphosarcoma and secondary hypercalcaemia. After induction chemotherapy the dog became severely hypocalcaemic and showed signs of weakness, muscle fasciculation and facial pruritus. Hormone analysis confirmed inadequate production of parathyroid hormone. Although hypocalcaemia has been previously reported as a component of tumour lysis syndrome, it has not been associated with transient parathyroid hormone deficiency.  相似文献   
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Results are presented for monitoring Salmonella infection by bacteriological culture and immune response (enzyme linked immunosorbent assay (ELISA) and haptoglobin) testing of samples collected from beef cattle at a single feedyard sampled over time. A total of 120 beef steers were examined on entry to the feedyard and at days 30, 60, and at time of slaughter (120-150 days). Isolations of Salmonella decreased over time from 40% of the steers sampled at day 0 to 0% at slaughter, whereas serological results varied by serogroup. Seropositivity increased for Salmonella group B up to day 60, and subsequently decreased to about half of the 60-day positivity rate at the time of slaughter. No significant changes in seropositivity were detected during the course of the study for the four other Salmonella serogroups (C1, C3, D1, and E1). Haptoglobin measurements were not a good indicator of Salmonella infection status. Sequential Salmonella testing either by culture, ELISA, or both could be used to monitor pathogen control practices.  相似文献   
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A 6-year-old female Alaska Malamute dog was presented for evaluation of abdominal enlargement referred by a local veterinarian. On the history, the owner complained of chronic abdominal enlargement initiated more than 4 months ago, reduced appetite, occasional vomiting and general dullness. He also complained of greenish mucous intermittent vaginal discharge starting 10 days ago. The bitch was chronically treated with medroxiprogesterone acetate. A laparatomy was performed and fluid in the abdomen was found and aspirated during the surgery. Also a very fluid-filled distended uterus and a mass in the distal part of the left uterine horn were found. The mass was encapsulated by the omentum, but areas of necrosis and calcification were identified. Histopathological diagnosis was endometrial adenocarcinoma.  相似文献   
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