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The objective of the study was to determine if there was a relationship between hematological, immunological and physiological variables of newborn calves and risk of diarrhea during the neonatal period. Four hundred and seventeen heifer calves from two dairies (A and B) in the San Joaquin Valley of California were enrolled at birth and scored daily, to 28 days of age, for evidence and severity of diarrhea (0 to 3). Calves were weighted at birth and blood sampled at two to five days of age to determine packed cell volume (PCV), total protein (TP) and IgG serum concentration. The Cox proportional hazards model was used to determine if age at onset of the first diarrhea episode and length of the first episode were associated with the hypothesized variables (PCV, TP, IgG and birthweight). The IgG concentration was not associated with the age at onset of diarrhea (p = 0.6052, Dairy A; p = 0.4393, Dairy B) but a high IgG concentration was associated with a decreased length of episode (p = 0.0325, Dairy A; p = 0.0912, Dairy B), particularly for calves born in the winter on dairy A (p = 0.0211). For calves born in the winter, those with either a high or a low birthweight had diarrhea at a younger age (p = 0.0102, Dairy A; p = 0.0020, Dairy B). Associations were also found for PCV and TP with both the age at onset and length of the first episode of diarrhea. Results suggest that parameters measurable at, or shortly after birth may have important prognostic value in evaluating risk of calf diarrhea.  相似文献   
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Torsion of abdominal organs in sows: a report of 36 cases   总被引:3,自引:3,他引:0       下载免费PDF全文
Necropsy records of 36 sows with torsion of abdominal organs involving individually the stomach, the spleen, a liver lobe or the intestine were reviewed for the years 1970 to 1983, and the age, the clinical signs and the gross lesions were recorded. These acute abdominal accidents were characterized clinically by sudden death. Dry sows from large breeding units were affected. Twenty-six cases were diagnosed between January 1981 and December 1983 while only ten cases had been seen between 1970 and 1980. Gastric torsion was the most common condition (40% of the cases) and the other three conditions were equally represented (20% each). Management practises that could be responsible for the apparent increase in occurrence of this problem are discussed.  相似文献   
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A transitional cell carcinoma of the urinary bladder was found in a beluga whale stranded in the St. Lawrence middle estuary. Various organs of this animal were submitted to high resolution gas chromatography coupled with mass spectrometry analysis. High frequency of urinary bladder cancer in the human population of the same area and the presence of carcinogenic compounds in the marine environment of this animal are discussed.

Concurrent isolation of Edwardsiella tarda from various organs of this whale is also reported.

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Summary On two occasions an anaplasm was isolated from sheep on the Dutch island of Ameland. The organism proved to be highly pathogenic for splenectomised sheep; a non-splenectomised animal recovered spontaneously after the packed cell volume had decreased by 40%. Treatment with oxytetracycline was effective. Its pathogenicity for goats appeared to be low, and the organism was apparently not infective to splenectomised cattle. This anaplasm differs from Anaplasma ovis in that less than 30% of the organisms are marginally situated in the red cell, as against over 70% in A. ovis; cross-immunity with A. ovis was incomplete and the latter appeared to be far more pathogenic to goats than the Dutch anaplasm, for which the name Anaplasma mesaeterum sp.n. is proposed. Its ultrastructure is similar to that of A. marginale and A. ovis. The vector is either Ixodes ricinus or Haemaphysalis punctata. Its practical importance remains to be ascertained.  相似文献   
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The fungal pathogenPhytophthora infestans is the causal organism of late blight, one of the most devastating diseases of potato. In the past, various aspects of the potato-P. infestans interaction have been studied extensively. In this paper we briefly review the current knowledge of the molecular events associated with the interaction and in addition we discuss a new approach for analyzing the molecular basis of pathogenicity ofP. infestans.  相似文献   
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Second-intention repair is faster in ponies than in horses and faster in body wounds than in limb wounds. To a large extent, the differences between horses and ponies can be explained by differences in the local inflammatory response, which are a result of the functional capacity of leukocytes. In ponies, leukocytes produce more inflammatory mediators,resulting in better local defense, faster cellular debridement, and a faster transition to the repair phases, with more wound contraction. In horses,leukocytes produce fewer mediators, initiating a weak inflammatory response, which becomes chronic. This inhibits wound contraction and gives rise to the formation of exuberant granulation tissue. The anatomic environment that influences the inflammatory response and wound contraction most probably determines the differences between body and limb wounds. In body wounds, better perfusion results in faster initiation of the inflammatory phase. The weaker local resistance results in a greater degree of contraction. In limb wounds, particularly of horses, the initial inflammatory response is weak and wound contraction is restricted. Both factors give rise to chronic inflammation, which further inhibits wound contraction and promotes exuberant granulation tissue. The high incidence of exuberant granulation tissue in limb wounds of horses can thus be explained by the chronicity of the inflammatory response as well as by the common use of bandages during treatment. Chronic inflammation is often not recognized as a cause of exuberant granulation tissue. It must be prevented and treated to promote the healing process. Bandages and casts stimulate the formation of exuberant granulation tissue; however, they are advantageous in many respects and play an important role in support of the overall healing process.  相似文献   
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Basic principles of surgery are important to review, even for experienced surgeons. Although aseptic surgical principles are not always applicable in the field, we have to respect some guidelines. Recent research will influence the way that we do things, based on what we have been taught and our experience. Respecting those simple principles can make a big difference in the final outcome.  相似文献   
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