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991.
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A single, artificially-induced fly-strike with Lucilia sericata larvae was associated with a rapid (decline in food intake in sheep, with a consequent reduction in liveweight. Loss of weight ranged from 0.5 to 5.5 kg over four to six days and recovery to pre-infestation liveweight took three to 36 days. Pair-fed, uninfested partners of these sheep also showed a reduction in liveweight, whereas uninfested sheep in some experiments fed ad libitum showed either little change or a gain in liveweight over the same period. In general, maggot infested sheep took less time to regain weight than did their pair-fed partners although the weight lost as a proportion of initial weight was similar in both groups. Loss of appetite alone would appear to account for these events.  相似文献   
996.
Dyserythropoiesis characterized by enhanced intramedullary destruction, pathologic sideroblasts and siderocytes, and hemoglobin crystallization was detected in a female Cocker Spaniel presented for poor exercise tolerance. Examination of peripheral blood revealed intraerythrocytic crystals, granulation of erythrocytes, nucleated erythroid cells, reticulocytosis and marked variation in erythrocyte morphology in the absence of anemia. Bone marrow examination revealed sideroblasts, a low M:E ratio and evidence of enhanced intramedullary destruction of erythroid cells. Electron microscopy of peripheral blood and bone marrow confirmed pathologic mitochondrial iron accumulation in erythroid cells and the presence of intraerythrocytic hemoglobin crystals. A cause for the hematologic changes was not identified. After the animal became clinically normal, siderocytes disappeared from peripheral blood but intraerythrocytic crystals and reticulocytosis persisted.  相似文献   
997.
Hookworm infected dogs had higher blood basophil counts than hookworm negative dogs. Dogs with occult heartworm infection (i.e., without microfilaremia) had higher blood neutrophil counts than heartworm negative dogs. The percentage of eosinophils in peripheral lymph nodes was higher in heartworm infected, microfilaremic dogs than in both occult infected dogs and heartworm negative dogs. Heartworm or intestinal parasitic infection had no other significant effects on hematologic parameters or peripheral lymph node cytology.  相似文献   
998.
Prednisone was give norally(2mg/kg b.i.d.) to seven healthy mixed breed dogs for 3 consecutive days. Serum iron concentration increased significantly (p < 0.05) from 142 +/- 26 micro g/dl (mean +/- SE) before a drug adminis- tration on Day 0 to a maximum of 307 +/- 47 micro g/dl on Day 2, and returned to the Day 0 value by Day 5. Mean total iron binding capacity did not vary more than 25% from the Day 0 value during the 9 day long study. The percent saturation of transferrin with iron increased from 33 +/- 6% on Day 0 to a maximum of 71 +/- 9% on Day 3. This determination had decreased to 34 +/- 3% on Day 5. No statistically significant changes occurred in these parameters studied in six control dogs that were not given the drug. To determine whether serum iron concentration might be correlated with endogenous serum cortisol concentration, these tests were determined in serum collected from nine dogs at 7 a.m., 3 p.m., and 11 p.m. each day for 3 consecutive days. Serum iron concentration was lower at 7 a.m. (147 +/- 9 micro g/dl) than at 3 p.m. (164 +/- 9 micro g/dl) or 11 p.m. (159 +/- 10 micro g/dl). Likewise serum cortisol was lower at 7 a.m. (1.29 +/- 0.18 micro g/dl) than at 3 p.m. (1.49 +/- 0.19 micro g/dl) or 11 p.m. (1.51 +/- 0.22 micro g/dl). There was a significant positive linear correlation between serum iron and serum cortisol concentrations when they were compared using mean values for each dog. From these studies, it appears that exogenously administered glucocorticoids and endogenous increases in serum cortisol concentrations may result in increased serum iron concentrations in dogs.  相似文献   
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Latissimus dorsi and cutaneous trunci myocutaneous flaps of equal dimension and location were randomly elevated on opposite sides of the thorax in 10 dogs (group 1) and resutured to their respective bed. The procedure was repeated in four additional dogs (group 2); however, the short perforating branches of the thoracodorsal artery and vein were divided at the base of each cutaneous trunci myocutaneous flap, whereas the cutaneous pedicle and underlying cutaneous trunci muscle were divided in the latissimus dorsi myocutaneous flaps to determine subsequent skin survivability and the major source of circulation of each myocutaneous flap. There was little difference in the percentage of skin survival between the latissimus dorsi and cutaneous trunci myocutaneous flaps in group 1 dogs. Circulation to the "skin island" of group 2 latissimus dorsi myocutaneous flaps originated from intramuscular anastomotic connections between the major branch of the thoracodorsal artery entering the latissimus dorsi muscle and the proximal lateral intercostal arteries perforating the muscle. Ligation of the short perforating branches of the thoracodorsal artery resulted in partial skin necrosis in all group 2 cutaneous trunci myocutaneous flaps. Results from this study indicate that it is unnecessary to elevate the latissimus dorsi muscle for major skin flap elevation and survival. The thicker latissimus dorsi myocutaneous flap is more difficult to develop surgically and appears to have no clinical major advantage over the more mobile cutaneous trunci myocutaneous flap or the adjacent thoracodorsal axial pattern flap for closure of large skin defects within the radius of flap rotation.  相似文献   
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