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121.
AIMS: To gather information on management practices and farmer attitudes to management of cows and calves during the immediate post-partum period on dairy farms in New Zealand, and to assess these practices for associations with concentrations of total protein (TP) in serum of calves 1–8 days-old.

METHOD: Between July and September 2015 blood samples were collected from calves aged between 24 hours and 7 days, from dairy farms (n=105) in nine areas in New Zealand, on three occasions throughout the calving period. Concentrations of TP were determined in all serum samples. At each visit technicians collected 1?L of the pooled colostrum that was intended for feeding to newborn calves that day. These samples were assessed for Brix, coliform and total bacterial counts. After the last sampling visit, the calf rearer or farm manager were asked to complete a questionnaire describing calf and colostrum management practices on the farm. Potential farm-level variables associated with concentrations of TP in serum of sampled calves were identified using univariable and multivariable linear mixed models.

RESULTS: Mean concentration of TP in serum of calves across all farms was 59.8 (95% CI=59.4–60.2) g/L, and was associated with region and herd size in the final multivariable model. Concentrations of TP were lower in calves from farms in Otago (56.2 (95% CI=53.4–58.9) g/L) and Southland (56.9 (95% CI=54.1–59.7) g/L) compared to calves on farms in the Far North (62.6 (95% CI=59.8–65.3) g/L), and were lower in calves from farms with a herd size >600 (58.3 (95% CI=56.7–59.8) g/L) than ≤600 (61.3 (95% CI=60.1–62.5) g/L) cows. After accounting for fixed effects, farm accounted for only 8.4% of the unexplained variation. There was no association between any of the measures of colostrum quality and concentrations of TP in serum (p>0.2).

CONCLUSION AND CLINICAL RELEVANCE: Very few herd-level variables were associated with concentrations of TP in serum. Risk factors that have been shown to be of importance in previous studies outside New Zealand were not identified as important in the current study. It is possible that, in the situation where calves are kept at pasture with their dams for prolonged periods, variables which influence how well a cow can feed its calf in the first 12–24 hours have a larger influence on concentrations of TP in serum than the collection and management of calves once they reach the rearing shed.  相似文献   
122.
SUMMARY Forty cats with hyperthyroidism were treated using 200 to 300 (typically 250) mBq of orally administered 131I. Thirty-six cases (90%) were successfully treated, as assessed by resolution of clinical signs and reduction In plasma thyroxine concentrations to normal or reduced values after treatment. Although higher doses of 131I appear to be required when the radioisotope is administered orally rather than Intravenously, a less stressful administration procedure and greater availability of therapy capsules offer useful advantages for treating thyrotoxic cats.  相似文献   
123.
贵州优良草坪草种质资源评价   总被引:1,自引:1,他引:0  
通过对1998-2000年引种征集的19个草坪草品种特性试验以及对供试草种的密度、质地、色泽、均一性、抗性等进行测定,分析表明:参试的19个草坪草品种,大多数在独山地区的气候、土壤等自然条件下生长良好,是较理想的草坏草,可供生产上利用。  相似文献   
124.
OBJECTIVE: To evaluate the effects on plasma cortisol concentration of a continuous infusion of a readily available steroid with equipotent glucocorticoid and mineralocorticoid effects. PROCEDURE: Plasma cortisol concentrations were measured before and regularly after hydrocortisone sodium succinate was administered as a continuous intravenous infusion over 6 h at 0.32 and 0.65 mg kg-1 h-1 to 12 healthy dogs weighing 12 to 22 kg. RESULTS: The infusion at both does rates produced significant and stable increases in plasma cortisol concentrations. The plateau concentrations produced by the large and small doeses were respectively above and below plasma cortisol concentrations likely to provide adequate glucocorticoid and mineralocorticoid activity in stressed dogs with significantly decreased adrenal function. CONCLUSION: This paper presents information regarding the changes in plasma cortisol concentrations in 12 normal dogs given an hydrocortisone sodium succinate infusion at two dose rates. The marked and continuous increase in plasma cortisol concentrations suggests a continuous HSS infusion may be a possible alternative to desoxycorticosterone acetate and dexamethasone in the treatment of acute adrenal dysfunction.  相似文献   
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