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941.
Cytologic sampling of the ultrasonographically normal spleen and liver is not implemented routinely in the clinical staging of canine cutaneous mast cell tumors and normal ultrasound findings are often accepted as sufficient evidence for ruling out splenic or liver metastasis. Our objective was to define the specificity and sensitivity of ultrasound findings for diagnosis of mast cell infiltration when verified with cytologic evaluation, and to define the prognostic role of cytologic evaluation of liver and splenic aspirates. Dogs with a diagnosis of clinically aggressive grade II, or grade III mast cell tumor treated with a combination vinblastine/CCNU chemotherapy protocol, were selected retrospectively based on availability of cytologic evaluation of spleen plus or minus liver for staging. Out of 19 dogs, 10 dogs had a grade II tumor and nine a grade III tumor. Seven dogs had mast cell infiltration of the spleen, liver, or both. The sensitivity of ultrasound for detecting mast cell infiltration was 43% for the spleen and 0% for the liver. Dogs with positive cytologic evidence of mast cell infiltration to spleen, liver, or both had significantly shorter survival (100 vs. 291 days) than dogs without evidence of mast cell infiltration (P<0.0001). Routine splenic aspiration should be performed regardless of ultrasonographic appearance in dogs with a clinically aggressive mast cell tumor.  相似文献   
942.
943.
Cytogenetic analysis and microsatellite genotyping were conducted on a pair of phenotypically normal dizygotic heterosexual equine twins of the American Bashkir Curly breed. The animals had a mixture of 64,XX and 64,XY cells in blood lymphocytes, with their own cells being predominant. Therefore, the 64,XX cells comprised 81% of the lymphocyte population in the female twin and 64,XY comprised 79% in the male twin. Blood chimerism was confirmed by genotyping 30 microsatellite markers. Of these, 15 microsatellites showed the presence of three alleles and all four parental alleles in the blood lymphocytes for both animals. No chimerism was detected in the genomic deoxyribonucleic acid isolated from hair follicles. These results are in agreement with earlier observations that vascular anastomoses can infrequently occur during equine multiple pregnancies resulting in blood lymphocyte chimerism without significant effect on the phenotype.  相似文献   
944.
The sperm of European eel shows a high density and the time of spermatozoa motility is very short after activation with sea water. These characteristics make difficult the sperm handling and its quality assessment. Several diluents were previously described for the Japanese eel obtaining over 3 weeks’ conservation times under refrigeration, but they rendered bad results in the European species. In the present study, several diluents were developed taking as basis the P1 medium, and using different dilution ratios (1 : 50, 1 : 100) and two pH (6.5, 8.5). The effect of the addition of bovine serum albumin (BSA, 2% w/v) was also evaluated. At 24 h, undiluted samples already showed significant lower motility and viability than sperm samples diluted in the different media. The results for diluents with pH 6.5 and 8.5 were different. Spermatozoa diluted in media at pH 6.5 cannot be activated at 24 h, while samples diluted in the diluents with pH 8.5 and added with BSA did not show significant differences with respect to the fresh sperm motility until 48 h. The viability (percentage of alive cells) did not show differences until 1 week, independent of the dilution ratio. After 1 week, the motility was approximately 30% in the media containing BSA, which presented no differences for head size of the spermatozoa (perimeter and area) until 72 h and 1 week, respectively. In conclusion, the combination of one medium having similar physico‐chemical characteristics to the seminal plasma, including pH 8.5, and supplemented with BSA can be used in different dilution ratios for the sperm’s short‐term storage, preserving its motility capacity.  相似文献   
945.
This paper describes the main features of fish aquaculture in Europe and Italy focusing attention on single sectors of the farmed species and their trend for the future. Over recent years, European and Italian aquaculture have shown a markedly different trend from that of world aquatic production. Asia, particularly China, has recorded a constant and rapid growth and Latin America a moderate development. Nowadays, European farmers are concerned with adapting their product to market demand and diversifying the fish species reared. After a discussion about the main European production statistics regarding finfish aquaculture production, we consider the most important aspects in the promotion of production and consequent consumption of farmed fish.  相似文献   
946.
To determine the current distribution of bovine dermatophilosis in Zimbabwe, participatory rural appraisals were held at 36 locations in six districts. Results showed that bovine dermatophilosis is no longer confined to Hwange-Lupane area, but is now endemic in Gokwe, Sanyati, Kwekwe, and Kadoma. Virgin outbreaks of the disease were preceded by the appearance of Amblyomma variegatum ticks within an area. Spreading to new geographical areas (cited above) occurred during the liberation struggle (1975/79), droughts (1992/93, 1995/96), and of late, the land re-distribution exercise (2000–2002). Immediately after the war (1980/82), both the ticks and the disease were first cited in Gokwe whereas prior to that (1922–1980), both were confined to Hwange-Lupane area in the northwestern parts of Zimbabwe. Transmission from Gokwe to Sanyati, and from Sanyati to Chenjiri, occurred during the droughts of 1992/93 and 1995/96 respectively. In all the cases, the spreading of dermatophilosis was secondary to reduced tick control on cattle. The presence of dermatophilosis in the highveld (Kwekwe, Kadoma), a prime cattle production zone for the country, is a major threat to livestock production. These results have policy implications for tick and tick-associated diseases (dermatophilosis) control strategies for Zimbabwe.  相似文献   
947.
948.
949.
Coagulase-negative staphylococci (CNS) have become the most frequently isolated organisms from bovine intramammary infections in recent years. While antimicrobial resistance (AR) is not considered a major problem among mastitis pathogens, concerns over emerging AR in general are increasing worldwide. Little information exists about the association between AR and one of the most common mastitis control measures, antibiotic dry cow therapy. The primary objective of the current study was to determine the prevalence of AR in CNS isolated before and after antimicrobial dry cow therapy. An additional objective was to genotypically characterize selected CNS isolates using pulsed-field gel electrophoresis (PFGE), to assess diversity and persistence of organisms over the dry period. Resistance against 10 antimicrobials was determined using a broth microdilution method and compared between CNS isolates collected at dry-off and at calving and from cows treated or not treated with intramammary antimicrobial products at dry-off (752 cows in total). Results suggested that increasing age of a cow and dry cow treatment when combined with high milk somatic cell count at dry-off and positive clinical mastitis history, were associated with increased AR to most beta-lactam antimicrobials and sulfadimethoxine. PFGE results suggested considerable diversity among the tested isolates as well as some clusters within cows and herds. PFGE would be useful in distinguishing between potentially persisting infections and cures and reinfections with different CNS strains.  相似文献   
950.
Glimepiride and nateglinide are two common oral hypoglycemic agents currently being used with humans suffering from Type 2 diabetes mellitus. Neither drug has been tested with cats thus far and it is currently unknown whether either of these drugs exert any effect in cats or not. The objective of this study was to determine the effect of glimepiride and nateglinide on glucose and insulin responses in healthy control cats, in order to determine their potential use in diabetic cats. The intravenous glucose tolerance tests was carried out since it is an excellent test for evaluating pancreatic β-cell function for insulin secretion. Alterations in the insulin secretion pattern can be perceived as the earliest sign of β-cell dysfunction in many species, including cats. Nateglinide demonstrated a quick action/short duration type effect with serum glucose nadiring and insulin response peaking at 60 and 20 minutes, respectively. Alternatively, glimepiride is medium-to-long acting with serum glucose nadiring and insulin response peaking at 180 minutes and 60 minutes, respectively. Nateglinide’s potency was evident allowing it to induce a 1.5–2 higher preliminary insulin peak (3.7?±?1.1 pg/ml) than glimepiride’s (2.5?±?0.1 pg/ml), albeit only for a short period of time. Because glimepiride and nateglinide have a shared mode of action, no significant differences in overall glucose AUC0-360min (24,435?±?2,940 versus 24,782?±?2,354 mg min/dl) and insulin AUC0-360min (410?±?192 versus 460?±?159) in healthy control cats were observed. These findings may provide useful information when choosing a hypoglycemic drug suited for the treatment of diabetic cats depending on the degree of diabetes mellitus the cat is suffering from.  相似文献   
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