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31.
A total of 959 faecal samples were obtained from dogs in 12 native communities in Northern Saskatchewan, Central and Northern Alberta and the Northwest Territories. All samples were examined using a flotation technique. Samples from an area of endemic human amoebic infections were also examined by a formol-ether sedimentation method. Eighteen necropsies were performed.

Entamoeba histolytica cysts were recovered from dog faeces at Loon Lake, Saskatchewan.

Toxocara canis had low incidence in Saskatchewan and Central Alberta, and appeared to be almost non-existent further North. Toxascaris leonina was found in all areas surveyed. Canine hookworm infections were plentiful in all areas, the highest incidence being recorded from Northern Alberta and Northwest Territories. Many Taenia (or Echinococcus) infections were found consistently in all areas. Only one infection with Dipylidium caninum was discovered.

Metorchis conjunctus infections were found to be common in the Saskatchewan reserves. Infections with Diphyllobothrium sp. were found in all communities with access to good fishing. One specimen of Dioctophyma renale was recovered at necropsy.

Infections with parasites of no known zoonotic importance such as Trichuris, Alaria and Isospora species were also recorded.

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A total of 55 non-surgical collections, 7 days after spontaneous heat, was made in 19 heifers. Recovery rate was 57% (17/30) from 10 repeat breeder heifers and 72% (18/25) from 9 virgin heifers, this difference was not significant. Fertilization rate in both groups was 94%. The eggs were always recovered in the first 100 ml of flushing medium. Mean lengths of oestrous cycle after non-surgical collection were, respectively, 16.9 and 18.1 days in repeat breeder and virgin heifers. This difference was not significant. However, the cycle in which the first collection was made was significantly shorter (P<.005) than the cycle immediately before the collections. Only 61% of possible eggs were non-surgically collected from 4 superovulated repeat breeder cows and no further eggs were found after slaughter, one to two hours later.  相似文献   
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A method for preparation of chromosomes from bovine zygotes and blastocysts   总被引:2,自引:0,他引:2  
A simple technique for making chromosome preparations from zygotes and early blastocysts is described. The morphological features of blastocysts and total number of cells greatly influence the quality of the preparation.  相似文献   
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This retrospective study in 39 dogs with incompletely resected oral melanoma examined the efficacy of hypofractionated radiation therapy and platinum-containing chemotherapy. All dogs were completely staged, with the majority of dogs classified as stage 1. Dogs received 6 weekly fractions of 6-gray (Gy) megavoltage irradiation with a cobalt-60 unit or a 4-MeV (megaelectron volts) linear accelerator. Dogs received cisplatin (10-30 mg/m2 IV) or carboplatin (90 mg/m2 IV) chemotherapy 60 minutes before radiation delivery. Durations of local control, metastasis-free survival time, and overall survival time were recorded. By the Kaplan-Meier method, 15% of the dogs had local recurrence within a median time of 139 days. Fifty-one percent of the dogs developed metastatic disease within a median time of 311 days (range, 24-2, 163 days). Median survival time for all 39 dogs was 363 days. The combined use of chemotherapy and radiation therapy in this protocol provided local control consistent with previous studies. Low-dose chemotherapy was used with the intent of enhancing radiation therapy for the local control of an incompletely excised tumor. Survival times were longer than previously reported for dogs with oral malignant melanoma. Additional studies are required to determine whether these results were due to the effects of chemotherapy on microscopic disease or the enhanced local control provided by chemoradiation therapy.  相似文献   
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