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61.
62.
1.?The effects of injecting threonine in ovo on early growth, some immunological responses and the activity of digestive enzymes of broiler chicks were investigated. Fertile eggs were distributed into 6 groups, each of 60. These were: untreated control, sham control, 10, 20, 30 or 40 mg threonine. Threonine was dissolved in 0·5 ml sterile saline and inoculated into the yolk sac of the 14-d-old embryo through the narrow end of the egg.

2.?The ratio of chick to egg weight was 1·6% higher in the group given 30 mg threonine and at 28 d of age chicks receiving threonine were 29 to 79 g heavier than untreated controls.

3.?Food conversion ratio until 7 d after hatching was improved in those chicks receiving 10, 20 or 40 mg threonine but there was no significant effect on the activities of amylase, pepsin or trypsin.

4.?The humoral response to sheep red blood cells was significantly greater in those groups receiving 10, 20 or 30 mg threonine supplementation than in untreated controls.

5.?The response to phytohaemagglutinin-P, a measure of the cell-mediated immune response, was not affected, however.

6.?It is concluded that injections of 20 to 30 mg threonine into yolk sac can improve post-hatching growth and humoral responses of broiler chicks.  相似文献   

63.
Background: This study addresses the antitumoral properties of Penicillium purpurogenum isolated from a polluted lagoon in Northeastern Brazil. Methods: Ethyl Acetate Extracellular Extract (EAE) was used. The metabolites were studied using direct infusion mass spectrometry. The solid Ehrlich tumor model was used for antitumor activity. Female Swiss mice were divided into groups (n = 10/group) as follows: The negative control (CTL−), treated with a phosphate buffered solution; the positive control (CTL+), treated with cyclophosphamide (25 mg/kg); extract treatments at doses of 4, 20, and 100 mg/kg; animals without tumors or treatments (Sham); and animals without tumors treated with an intermediate dose (EAE20). All treatments were performed intraperitoneally, daily, for 15 days. Subsequently, the animals were euthanized, and the tumor, lymphoid organs, and serum were used for immunological, histological, and biochemical parameter evaluations. Results: The extract was rich in meroterpenoids. All doses significantly reduced tumor size, and the 20 and 100 mg/kg doses reduced tumor-associated inflammation and tumor necrosis. The extract also reduced the cellular infiltration of lymphoid organs and circulating TNF-α levels. The extract did not induce weight loss or renal and hepatic toxic changes. Conclusions: These results indicate that P. purpurogenum exhibits immunomodulatory and antitumor properties in vivo. Thus, fungal fermentation is a valid biotechnological approach to the production of antitumor agents.  相似文献   
64.
65.
The study was conducted to evaluate the meat texture, muscle proximate composition, lipid class composition, and collagen content of cultured amberjack and to compare these parameters with those of the yellowtail. Our results showed that the meat texture of cultured amberjack was tougher and had a lower degree of seasonality than that of cultured yellowtail. Muscle lipid and collagen content also varied in the two fish species over the study period. Meat breaking strength was not correlated with any of the muscle constituents, indicating that variations in the meat texture of cultured amberjack was not directly influenced by the changes in the muscle biochemical constituents.  相似文献   
66.
ABSTRACT

In the scheduling of nutrient supply programs, analysis of plant nutrient status has been found to be useful to prevent the deficiency or toxic effects of nutrients in any horticultural crop. So the present study was framed to assess the foliage nutrient content and vegetative growth under different irrigation and fertigation combination modules. Recently apple (Malus ×domestica) orchards in the state Himachal Pradesh of India have converted from the traditional royal delicious orchard at 6 × 6 m spacing with rainfed/basin irrigation to early spur varieties on dwarfing rootstock with drip irrigation, both with or without fertigation. An experimental field trial was started at the end of 2018 in a ‘Super Chief’/MM106 orchard at an experimental farm of the department of Soil Science & Water Management, Dr. YS Parmar University of Horticulture and Forestry, Nauni, Solan (HP). A factorial experiment with 16 treatment combinations of 4 irrigation levels viz. I1 – drip irrigation at 100% ETc, I2 – drip irrigation at 80% ETc, I3 – drip irrigation at 60% ETc, I4 – conventional irrigation, and four fertigation levels viz. F0 – No fertilizer application (absolute control), F1 – 100% of AD (NPK), F2 – 75% of AD (NPK) and F3 – 50% of AD (NPK) were replicated thrice with 3 plants in each replication. Vegetative growth parameters and leaf nutrient contents were affected by both fertilization and water rate. Irrigation and nutrient levels and their interactions exhibited significant effect on leaf N (3.10%), P (0.28%), K (1.77%), and S (0.44%) contents. Significantly maximum contents were observed in the irrigation level I1 (DI at 100% ETc). Among fertigation level, F1 [100% AD (NPK)] recorded highest contents of leaf N (3.17%), P (0.29%), K (1.80%), S (0.46%). Interaction I1F1 registered maximum leaf N (3.36%), P (0.36%), K (1.92%) and S (0.63%).

With an increase in the water volume and an increasing dose of NPK, vegetative growth parameters, i.e., tree height, plant spread, tree volume, trunk girth, and annual extension growth were noted to increase proportionately. Treatment DI at 100% ETc (I1), increased the tree height by 9.41, plant spread (EW by 32.0, NS by 16.3), tree volume by 61.36, trunk girth by 8.05, and annual extension growth by 14.22% over conventional irrigation (I4). Drip fertigated trees with F1 [100% AD (NPK)] reported the highest growth parameters. The results of two years apple trial suggested a positive effect of fertigation on enhanced effectiveness of fertilization and improved foliage nutrient content and vegetative growth.  相似文献   
67.
Endogenous cyclic AMP levels and the activities of adenylate cyclase, cyclic AMP-dependent and independent protein kinases were examined in testes of mature rats bilaterally vasectomized for one, three and seven months. Although no significant alteration in testicular cyclic AMP was detected one month following vasectomy, marked decreases (by 55% and 32%, respectively) were seen three and seven months postvasectomy. Likewise, vasectomy also resulted in a significant decrease (by 25%) in the activity of testicular adenylate cyclase three and seven months after vasectomy. Although soluble cyclic AMP-dependent protein kinase activity remained unaffected three months postvasectomy, the activity of the cyclic nucleotide-dependent enzyme was significantly increased (by 21%) when compared to the sham-operated controls. Furthermore, while the protein kinase ratio (--cyclic AMP/+cyclic AMP) was decreased in animals vasectomized for three months, the ability of the enzyme to bind (3H) cyclic AMP in vitro was significantly enhanced (18%). Rats vasectomized for seven months showed similar biochemical alterations but the effects of this procedure were more pronounced. Moreover, while short-term vasectomy increased the responsiveness of seminiferous tubular adenylate cyclase to in vitro stimulation by follicle stimulating hormone, the activity of the enzyme was also increased (by 100%) in the presence of luteinizing hormone in vasectomized rats. These data raise the possibility that changes in testicular function seen following vasectomy may be related to the alterations in cyclic AMP metabolism as well as in the sensitivity of testicular adenylate cyclase to regulation by gonadotropins.  相似文献   
68.
The effects of leaf age, leaf position on the shoot, sampling-direction and sampling-height of leaves of mango cultivar ‘Chausa’ on their mineral composition were studied. The P and K contents decreased, while Ca, Mg, S and Mn contents increased significantly with advancing age of leaves. In general, N, P, Mg, S, Zn, Mn and Fe contents were stable in 6- to 7-months-old leaves. P, K, Ca, Mn and Fe contents varied with sampling-direction, while K, Ca, S, Zn, Cu and Fe contents were significantly higher in the leaves from the lower portion than from the upper portion of the tree. A continuous increase in Ca and Mg contents and decrease in K and Mn contents of leaves were observed from basal to terminal leaves on a shoot. It was concluded that 6- to 7-months-old leaves from the middle of non-fruiting shoots, sampled from all directions and heights, were most suitable for assessing the nutritional status of a mango tree.  相似文献   
69.
Hydatidosis (cystic echinococcosis) constitutes a serious public health problem in the Province of Rio Negro, Argentina. In the present work it was intended to evaluate the prevalence of the canine echinococcosis in rural areas of the Province of Rio Negro and studied the reinfection rate in dogs after treatment with Praziquantel during the period 1980-1997. A total of 496 dogs were studied in 18 canine concentrations in order to establish the initial prevalence rate which was 42.3%. From 1980 onward dogs should have been systematically treated with anthelmintic every 2 months in rural areas and every 6 months in urban areas. We estimated that approximately 65% of dogs were treated. To determine the reinfection rate, 476 dogs (1984) and 598 dogs (1996) were studied after anthelmintic treatment during two sequential time periods (0-45; 46-90 days). In both cases treated animals were compared with untreated dogs. Prevalences were 3.5%, 6.7% and 21.3% in 1984 and 0.8%, 4.0% and 10.0% in 1996. For the purpose of surveillance a total number of 21,444 dogs were studied during 18 years. Prevalence of Echinococcus granulosus decreased significantly in the first year from 42.3% to 6.1%.  相似文献   
70.
The purpose of this study was to characterize the land use, vegetation structure, and diversity in the Barnowpara Sanctuary, Raipur district, Chhattisgarh, India through the use of satellite remote sensing and GIS. Land cover and vegetation were spatially analyzed by digitally classifying IRS 1D LISS III satellite data using a maximum likelihood algorithm. Later, the variations in structure and diversity in different forest types and classes were quantified by adopting quadratic sampling procedures. Nine land-cover types were delineated: teak forest, dense mixed forest, degraded mixed forest, Sal mixed forest, open mixed forest, young teak plantation, grasslands, agriculture, habitation, and water bodies. The classification accuracy for different land-use classes ranged from 71.23% to 100%. The highest accuracy was observed in water bodies and grassland, followed by habitation and agriculture, teak forest, degraded mixed forest, and dense mixed forest. The accuracy was lower in open mixed forest, and sal mixed forest. Results revealed that density of different forest types varied from 324 to 733 trees ha-1, basal area from 8.13 to 28.87 m2·ha-1 and number of species from 20 to 40. Similarly, the diversity ranged from 1.36 to 2.98, concentration of dominance from 0.06 to 0.49, species richness from 3.88 to 6.86, and beta diversity from 1.29 to 2.21. The sal mixed forest type recorded the highest basal area, diversity was highest in the dense mixed forest, and the teak forest recorded maximum density, which was poor in degraded mixed forests. The study also showed that Normalized Difference Vegetation Index(NDVI) was strongly correlated to with the Shannon Index and species richness.  相似文献   
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