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901.
902.
For initial training, horses are often transferred from group housing to individual boxes, which is a potential stressor. In this study, salivary cortisol concentrations, locomotion activity, and heart rate (HR) were analyzed and the HR variability (HRV) variables standard deviation of beat-to-beat interval (SDRR) and root mean square of successive RR differences (RMSSD) were calculated in 3-year-old mares (n = 8). Mares were transferred abruptly from a group stable with access to a paddock to individual boxes without a paddock and were studied from 4 days before to 5 days after changing the stable. Mares underwent routine equestrian training for young horses. On the days before mares were moved to individual boxes, cortisol concentrations showed a diurnal rhythm with values approximately 0.6 ng/ml in the morning and a decrease throughout the day. When horses were moved to individual boxes, cortisol concentrations increased to 1.8 ± 0.2 ng/ml within 30 minutes and did not return to baseline values within 6 hours (0.7 ± 0.1 ng/ml, P < .05 over time). On the following days, a diurnal rhythm was re-established but at a higher level than before the change of stable. Locomotion activity was higher when mares had access to a paddock than when kept in individual boxes. Heart rate increased for approximately 60 minutes when mares were separated from their group. In conclusion, separating young horses from their group and individual stabling are perceived as stressful.  相似文献   
903.

Somatic cell score (SCS) decreases to a minimum at around 60 days postpartum and then increases until the end of lactation. This pattern was described with three non-linear mixed effects models. Parameters of the models were linear in fixed and random (cow) effects. Data were 1705 SCS test-day records (155 primiparous Holsteins) taken from 14 to 300 days in milk. Point estimates were the mode of the joint posterior distribution of fixed and random effects (given dispersion parameters) and approximate marginal maximum likelihood estimates of covariance components. Intramammary infection during lactation, season and period of calving affected SCS patterns. Estimates were similar with or without a relationship matrix. There was between-cow variation of trajectories, suggesting that SCS curve parameters can be modified by selection in some advantageous manner.  相似文献   
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906.
OBJECTIVE: To determine the effectiveness of using a disinfectant mat filled with a peroxygen compound to prevent mechanical transmission of bacteria via contaminated footwear between the food animal ward and common breezeway of a veterinary teaching hospital. DESIGN: Observational study. SAMPLE POPULATION: Shoe soles of individuals entering and exiting from the ward. PROCEDURES: A mat filled with peroxygen disinfectant was placed at the entrance to the food animal ward, and participants wiped each shoe twice on the mat surface (n = 16) or walked on the mat surface but did not wipe their shoes (17) before entering and exiting from the ward. Swab specimens were collected from the shoe soles of participants before and after mat use and submitted for bacterial culture. RESULTS: For both study days, as participants entered the ward, median number of aerobic bacteria isolated from shoe swab specimens collected prior to use of the disinfectant mat was not significantly different from median number isolated after use of the disinfectant mat. However, as participants exited the ward, median number of aerobic bacteria isolated from shoe swab specimens collected prior to use of the disinfectant mat was significantly higher than median number isolated after use of the disinfectant mat. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that placing a mat filled with a peroxygen disinfectant at the exit from the food animal ward of a veterinary teaching hospital may help reduce mechanical transmission of bacteria on the footwear of individuals leaving the ward.  相似文献   
907.
Melanocytic tumours are important in horses, especially grey horses. Intradermal common melanocytic naevi, cellular blue naevi and combined cellular blue naevi are subgroups of human melanocytic tumours, which have not been reported in horses. In this study, we describe 20 horses with skin tumours similar to these naevi of humans. These tumours represented individual skin masses in male and female horses of different breeds. Tumours resembling human intradermal common melanocytic naevi were noted in 12 horses aged between 2 and 17 years. Seven horses aged between 4 and 15 years developed cutaneous lesions similar to human cellular blue naevi. A combined cellular blue naevus-like tumour was diagnosed in a 20-year-old horse. All tumour types formed expansile, well-demarcated, non-encapsulated, symmetrical masses. Tumours similar to intradermal common melanocytic naevi were composed of nests of round and spindeloid neoplastic cells, often embedded in myxomatous stroma. Lesions resembling cellular blue naevi were formed by intradermal bundles of ovoid to elongated cells separated by collagen fibres. The combined cellular blue naevus-like tumour resembled human cellular blue naevus with in addition, an overlying junctional common melanocytic naevus. Neoplastic cells in all groups contained varying amounts of melanin pigment and were immunopositive for S100. These equine skin tumours differ from the commonly recognized equine melanocytic tumours by their cytomorphological features, random location and the absence of an increased tumour frequency in grey horses. The resemblance of these tumours to three distinct subgroups of human naevi expands the complexity of equine proliferative cutaneous melanocytic lesions.  相似文献   
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909.
An ethnographic case study of five rural farmwomen in Cedar County, Nebraska, was conducted to contribute to the understudied area of rural entrepreneurship and women entrepreneurs. This naturalistic inquiry into the lived experiences of five women provides an exceptional view of the founding of a new microenterprise, the St. James Marketplace, a farmer-to-customer market in an agricultural setting. The study considered factors identified from previous research on entrepreneurship in both urban and rural settings. It connected the formation of this microenterprise to the history, culture, values, and economic situation that motivated the founders’ entrepreneurial behavior. A social embeddedness perspective was employed in the analysis. Negative forces from the macroenvironment, such as the closing of the local church parish and declining economic conditions for farming, influenced the creation of the venture. However, the most important motivation was to sustain community. This study satisfies a need for in-depth inquiry into rural entrepreneurship, rural communities, and rural farmwomen entrepreneurs.
Sandra Sattler WeberEmail:
  相似文献   
910.
Bovine neonatal pancytopenia (BNP) is a recently described haemorrhagic disease of calves characterised by thrombocytopenia, leucopenia and bone marrow depletion. Feeding colostrum from cows that have previously produced a BNP affected calf has been shown to induce the disease in some calves, leading to the hypothesis that alloantibodies in colostrum from dams of affected calves mediate destruction of blood and bone marrow cells in the recipient calves. The aims of the current experimental study were first to confirm the role of colostrum-derived antibody in mediating the disease and second to investigate the haematopoietic cell lineages and maturation stages depleted by the causative antibodies. Clinical, haematological and pathological changes were examined in 5 calves given a standardised pool of colostrum from known BNP dams, and 5 control calves given an equivalent pool of colostrum from non-BNP dams. All calves fed challenge colostrum showed progressive depletion of bone marrow haematopoietic cells and haematological changes consistent with the development of BNP. Administration of a standardised dose of the same colostrum pool to each calf resulted in a consistent response within the groups, allowing detailed interpretation of the cellular changes not previously described. Analyses of blood and serial bone marrow changes revealed evidence of differential effects on different blood cell lineages. Peripheral blood cell depletion was confined to leucocytes and platelets, while bone marrow damage occurred to the primitive precursors and lineage committed cells of the thrombocyte, lymphocyte and monocyte lineages, but only to the more primitive precursors in the neutrophil, erythrocyte and eosinophil lineages. Such differences between lineages may reflect cell type-dependent differences in levels of expression or conformational nature of the target antigens.  相似文献   
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