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31.
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   
32.
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   
33.
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   
34.
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   
35.
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   
36.
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   
37.
The serological reactivity in indirect ELISA of five different bluetongue virus (BTV) serotypes (4, 10, 15, 16 & 20) was compared using polyclonal antisera raised against virus particles and an outer structural protein, VP2. Rabbit and sheep antisera against BTV-10 produced higher ELISA values with their homologous antigens than with heterologous serotypes. A hyperimmune rabbit serum specific for virus particles was able to distinguish heterologous serotypes from each other, but a sheep serum from an infected animal was not. An antiserum directed against VP2, the protein responsible for serotype specificity in neutralization tests, was not serotype-specific in ELISA and cross-reacted with other serotypes. The discriminatory ability of a BTV-4 antiserum was improved by cross-absorption with heterologous antigens. This greatly reduced the ELISA signals with heterologous serotypes and produced an antiserum that was effectively serotype-specific.  相似文献   
38.
Behaviour of laying hens in a deep litter house   总被引:4,自引:0,他引:4  
1. Flocks of medium hybrid laying hens were housed in a modified deep litter system; the house was divided into 2, 3 and 4 pens in three successive years. Flock size was 300 or 370 and stocking density varied from 3.4 to 10.7 birds/m2. Higher densities used were above those recommended by the Ministry of Agriculture, Fisheries and Food (MAFF). 2. A random sample of 100 birds was identified with individual tags in each of the 9 flocks; regular observations using a scanning technique were made in each laying cycle to determine bird location and behaviour. 3. In all flocks the use of area by some individuals was uneven, that is, they were sighted in certain areas significantly more often than would have been expected by chance. The proportion of such individuals varied between flocks from 35 to 65%. Overall, birds spent more time on the slatted area than would have been expected from the area that it occupied. 4. A wide variety of different behaviour patterns was observed both on litter and on slats, but with foraging occurring more on litter and feeding more on slats. 5. Movement appeared to be constrained by crowding, because time spent in locomotion decreased in approximately linear fashion with increased stocking density. This provides support for MAFF recommendations of limits on stocking density in deep litter houses.  相似文献   
39.
40.
Cattle were immunized with vaccines containing modified-live or inactivated bovine respiratory syncytial virus (BRSV) and serum antibody responses were analyzed. Compared with preinculation values, at Day 14 after two biweekly immunizations with modified-live or inactivated vaccines there were significant increases in BRSV-specific titers in the sera of cattle that received both types of vaccines, as determined by a whole cell ELISA. Using a blocking ELISA and radioimmune precipitation it was determined that there was recognition of the fusion (F) protein by antibodies from cattle that received both types of BRSV antigens: however, virus neutralization assays revealed that only cattle that received modified live virus, either in monovalent or polyvalent vaccines, developed neutralizing antibodies to BRSV after two immunizations. These results indicate that inactivation of BRSV can lead to a dissociation between serological recognition of the F protein and virus neutralization in vaccinated cattle.  相似文献   
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