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71.
Four experiments with 270, 44, 432 and 66800 Leghorn hens were carried out to investigate the influence of various Mn additions to diets differed in mineral or Ca contents on egg shell quality. The addition of 300 mg Mn/kg diet improved significantly egg shell breaking strength by 4 N over one year. The supply of 50-500 mg Mn/kg diet for 10-24 weeks of the second half of laying year did not influence the egg shell quality. Addition of mineral mixture or Ca grit to layer rations with adequate or higher Mn levels did not influence egg shell strength. High mineral content in a low manganese diet increased number of cracks by 3%. Strength, weight and ash content of tibia were significantly reduced by feeding a low mineral level. Addition of 50-150 mg Mn per kg low mineral diet normalized partially tibia stability in young hens. It was concluded that supplied dietary Manganese influences calcification positively only in young hens. High levels of Ca did not influence the effects of Mn. 50 mg Mn per kg layers mixture have been considered as an essential supply.  相似文献   
72.
GSH-Px activity in blood and plasma of 269 horses was determined and interrelated to age, sex, and type of use or breed. Furthermore values in blood were related to hematocrit and hemoglobin contents. Trotters and riding horses had higher GSH-Px activities in plasma as well as in blood (0.83 +/- 0.22 and 0.79 +/- 0.23 U/ml plasma or 27.2 +/- 4.3 and 24.0 +/- 7.0 U/ml blood) than Thoroughbreds in training and yearlings (0.61 +/- 0.,14 and 0.56 +/- 0.16 U/ml plasma or 20.6 2 +/- 6.9 and 24.6 +/- 4.3 U/ml blood). 3 to 6 years old Thoroughbreds had higher GSH-Px-activities than 1 to 2 years old ones. Colts and fillies did not have differing values.  相似文献   
73.
46 one day old chickens, divided into five groups, were fed an alternately composed vitamin D3 ration during 36 days. In the group depleted of vitamin D3 the typical rickets were found. When treated with a standard ration (2000 I.U. vit. D3/kg food) after 15 days depletion of vitamin D3 the chickens showed control-group parameters within 3 weeks. Using 60,000 I.U. vitamin D3 after a period of 15 days depletion evoked rather an abrupt beginning of healing tendency accompanied by signs of intoxication which were enhanced in those chickens treated with 120,000 I.U. vitamin D3: increase in number of osteoblasts, calcification of osteoblastic mitochondrial membranes and endothelial cell membranes, as well as degeneration of osteoblasts together with a strong reaction of eosinophils. There did not occur necrosis of osteocytes or of bone structure. Erythrocytes, being embedded in ground substance without endothelial surrounding, was a common finding in every group.  相似文献   
74.
Differences in gas exchange parameters i.e. carbon exchange rate (CER), transpiration (Tr), water vapor conductance (g) were investigated, under a controlled environment, in a semi-dwarf (SD) Triticum aestivum line, its tall (TL) near isoline and the Payne (PA) variety characterized by small leaves. The plants were maintained in: (a) optimal substrate moisture condition (CTR); (b) salinized by watering with a 0.12 m NaCl solution (SLT); (c) water stressed by withholding waterings during a period of six days (STR); (d) stressed and salinized during the same period and with the same saline solution (S + S). CER and Tr were negatively affected by the stresses; SLT and S + S treatments had a higher WUE compared to their respective controls CTR and STR.
SD line had a better performance in terms of CER and WUE, particularly when water and salt stresses interacted. Leaf anatomy and assimilation/internal CO2 concentration curves contributed to explaining the SD performance.  相似文献   
75.
The proximal straight tubules of the female mouse kidney exhibit heavy periodic acid Schiff (PAS) staining in their brush borders and numerous cytoplasmic granules. In the present study, the female DBA/2Cr mouse kidney was examined, using various fixatives (formalin, PFA, PLP, Zamboni's, Bouin, or Carnoy solution) and various staining methods (HE, PAS, alcian blue, periodic acid methenamine-silver (PAM), toluidine blue, azan, or Congo red). Under azan and PAM, the staining pattern of the brush border was similar to that of PAS, and few effects of the fixative were observed. Cytoplasmic granules were clearly detected with PAM as well as PAS. However, these granules were not detected with Carnoy solution. Furthermore, distribution of granules differed between PAS and PAM.  相似文献   
76.
77.
Neutralising antibody to bovid herpesvirus 2 was demonstrated in the serum of 31 (10.8%) of 286 heads of cattle in north, south, and west Syria. 38% of titres were 1:2 to 1:8. There is no published report on isolation of this virus in Syria.  相似文献   
78.
Four adult, lactating dairy cows were subjected to diversion (loss) of gastric contents through a T-shaped cannula placed in the cranial part of the duodenum just distal to the pylorus. Diversion was continued for 10 to 12 hours, at which point the cows were very weak and depressed. The volume of effluent during this period ranged from 37.3 to 46.8 L, with the largest volume being produced during the first four hours. All cows became dehydrated, with mean packed cell volume and total plasma protein concentration increasing 30% and 19.6%, respectively, but with only a slight increase in plasma creatinine concentration. Plasma Cl- concentrations decreased from a mean of 97.3 mEq/L at the beginning of diversion to a mean of 87.2 mEq/L at eight hours. This was followed by a plateau or slight increase in concentrations over the final hours of diversion. Plasma K+ concentration followed a similar pattern, decreasing from a mean of 3.9 mEq/L to a mean of 2.94 mEq/L at six hours, followed by increasing values until termination of diversion. No changes in plasma Na+ concentration were noted, except for a mild decrease in one cow. Plasma calcium concentrations decreased significantly, reaching 6.6 +/- 0.6 mEq/L at the end of diversion. Venous pH, plasma HCO3- concentration, and plasma base excess concentration increased during the first four to eight hours of diversion, followed by a gradual decline. Although a mild hypochloremic metabolic alkalosis resulted from diversion of abomasal outflow in all cows, substantiated by a mild increase in plasma strong ion difference, the changes observed were not as great as expected.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
79.
Abstract. A humoral antibody response was demonstrated by ELISA in rainbow trout immunized intraperitoneally with extracts from the branchiuran ectoparasite Argulus foliaceus. A similar immunization protocol produced a higher titre response in a rabbit. Both trout and rabbit identified several antigenic components on immunoblots. ELISA and immunoblotting indicated that rainbow trout and rabbit anti-A. foliaceus sera identified components from the parasitic copepods Lepeophtheirus salmonis and Caligus elongatus.  相似文献   
80.
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