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81.
Metabolic hormones [insulin, leptin, insulin-like growth factor-I (IGF-I), thyroxine (T4) and triiodothyronine (T3)], progesterone (P4) and beta-hydroxybutyrate (BHB) serum concentrations were evaluated and their effect on the superovulation results of donor cows was investigated in a semi-arid environment. Body weight, body condition score (BCS) and lactation stage were also included in the analysis. Twenty-three Holstein-Friesian cows were superovulated with 600 IU FSHp following the routine procedure and flushed on day 7 in a Multiple Ovulation and Embryo Transfer Centre in the semi-arid area of Brazil. The corpora lutea (CL) were counted and blood samples were collected for assays. All of the hormones investigated and BHB serum concentrations were within the physiological ranges. There was a positive correlation between hormones, except between BHB and all the others. The leptin level was influenced by feeding status, as indicated by the BCS. Insulin, T4, T3 and BHB levels were affected by milking status. Dry cows had higher levels of all hormones except BHB. An optimum level of leptin resulted in the highest number of CL, while the linear increase of P4, T4 and IGF significantly increased the number of CL.  相似文献   
82.
In order to verify the fattening performance, slaughter and carcass characteristics and to investigate the changes in some meat quality traits of Karayaka lambs weaned at 3 months of age, 39 lambs (23 males and 16 females) were used as experimental animals. The lambs were fed a concentrate mixture and alfalfa hay (120 and 168 g crude protein and 2,700 and 1,951 ME/kg, respectively) for a period of 60 days of fattening period. Male lambs were superior (p < 0.05) to female lambs in terms of daily weight gain (270.4 vs. 205.4 g; SEM = 9.46), hot and cold carcass weights (16.7 and 16.0 vs. 14.1 and 13.4 kg, respectively; SEM = 0.35), intra-muscular fat ratios (1.9% vs. 2.5%; SEM = 0.12) and dripping loss of semitendinosus muscle 3 days postmortem (8.1% vs. 10.2%; SEM = 0.36). The relative weights of some organs, the meat quality traits (pH, cooking loss, shear force, CIELab colour characteristics) and proximate analyses (dry matter, protein and ash) of longissimus dorsi and semitendinosus muscle samples from lambs were not affected by sex (p > 0.05). Dripping loss, pH and colour characteristics were affected by storage time (p < 0.05). These results provide a basic understanding of performance and meat quality of Karayaka sheep which may have potentials in improving sheep production using an indigenous sheep breed in Turkey.  相似文献   
83.
Abstract

Effects of long-term use of phosphate fertilizers on extractable soil Cd in relation to its concentrations in plants were investigated. “Paired” soil samples were collected from newly and long-term cultivated fields and analyzed for Cd by extraction with NH4OAc, DTPA, NH4OAc-EDTA, NH4NO3, HCl and CaCl2. Plant samples were also collected and analyzed for Cd. Significant differences in extractable Cd by all the extractants except NH4NO3 were observed between the newly and long-term cultivated soils. The Cd concentrations in plants were not increased by the elevated extractable Cd. Although significant relationships were observed between plant Cd and extractable soil Cd, none of the extractants used alone gave a good assessment of plant-available Cd for all the samples used in this study.  相似文献   
84.
Abstract

Eighty four soil samples collected from southeastern Norway were analyzed for Cd by extraction with NH4OAc, DTPA, NH4OAc-EDTA, NH4NO3, HCl and CaCl2. The total Cd, pH, exchangeable K and Ca, dithionite-extractable Mn, available P and fine sand (0.2–0.02 mm) contents were the principal factors related to the extractable Cd, with some inter-extractant variations. Cadmium extracted by NH4NO3, NH4OAc, HCl and CaCl2 decreased with increasing soil pH, but the Cd extracted by all the extractants increased with increasing total Cd, exchangeable K and Ca, available P, and Mn-oxide contents in the soils. The Cd concentrations in plants were significantly related to the extractable Cd, exchangeable Ca and Mg, pH, Mn-oxides and organic matter content.  相似文献   
85.
Diazotrophic bacteria previously isolated from internal tissues of naturally regenerating lodgepole pine (Pinus contorta var. latifolia (Dougl.) Engelm.) seedlings were tested for their ability to fix N in association with western red cedar (Thuja plicata Donn.). Surface-sterilized cedar seed was sown in glass tubes containing an autoclaved sand/montmorillonite clay mixture that contained a N-free nutrient solution labeled with 15N as 0.35?mM Ca(15NO3)2 (5?% 15N label). After sowing, seed was inoculated with one of three bacterial strains: Paenibacillus polymyxa P2b-2R, P. polymyxa P18b-2R, or Dyadobacter fermentans P19a-2R. At the end of the 27-week plant growth period, P2b-2R was the only strain detected in the cedar rhizosphere. No bacteria were found inside plant tissues. Cedar foliar N concentrations were significantly enhanced (26–33?%, P?<?0.05) in response to inoculation with all three bacterial strains but 15N dilution (23?%, P?<?0.05) was observed only in seedlings treated with strain P2b-2R. This strain also reduced seedling dry weight (27?%, P?<?0.05). We observed similar trends in a second experiment with slight modifications to the protocol, but the magnitude of foliar 15N dilution was greater (56?%, P?<?0.05). Based on our results, we conclude that cedar seedlings inoculated with strain P2b-2R derived 23 and 56?% of their foliar N from bacterial N fixation in two seedling growth experiments.  相似文献   
86.
Wild melon diversity in India (Punjab State)   总被引:1,自引:1,他引:0  
We present here the first comprehensive genetic characterization of wild melon accessions from northern India. The genetic diversity among 43 wild melon accessions collected from the six agro-ecological regions of the Punjab State of India was assessed by measuring variation at 16 Simple Sequence Repeat (SSR) loci, morphological traits of plant habit and fruit morphological traits, two yield-associated traits, root nematode resistance and biochemical composition (ascorbic acid, carotenoids, titrable acidity). Variation among accessions was observed in plant habit and fruit traits and wild melon germplasm with high acidity and elevated carotenoid content and possessing resistance to Meloidogyne incognita was identified in the collection. A high level of genetic variability in wild melon germplasm was suggested by SSR analysis. Comparative analysis using SSRs of the genetic variability between wild melons from the north and other melons from the south and east regions of India and also reference accessions of cultivated melon from Spain, Japan, Korea, Maldives, Iraq and Israel, showed regional differentiation among Indian melon accessions and that Indian germplasm was not closely related to melon accessions from other parts of the world. A highly drought tolerant accession belonging to var. agrestis Naud. was also identified.  相似文献   
87.
Journal of Soils and Sediments - We conducted this project to develop a feasible method for mapping tropical peat lands of Bengkalis Island—as a test site—in Indonesia. The method based...  相似文献   
88.
Journal of Soils and Sediments - Heterogeneity of soil mineral particles may lead to the misinterpretation of bulk sorption data on their role in metal sorption, which may be resolved through the...  相似文献   
89.
The effects of salbutamol and norepinephrine on the electrocardiogram (ECG), serum potassium level and enzyme activities were studied in rabbits with hyperkalaemia; norepinephrine and salbutamol may be therapeutically useful. For induction of hyperkalaemia, 300 mM KCl solution was used and then isotonic saline solution containing 6 microg salbutamol and 3.9 microg norepinephrine per ml were administered. Norepinephrine and salbutamol decreased the serum potassium from 7.36 +/- 0.26 and 7.21 +/- 0.31 mmol/L to 5.62 +/- 0.27 and 4.35 +/- 0.33 mmol/L, respectively, and caused the ECG changes (flatness of P wave, widening of QRS complex and bradycardia) to return to the control conditions (time 0). Norepinephrine, but not salbutamol, decreased the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) to the control levels. These results suggest that monitoring of the enzyme activities might be useful as it yields indexes suitable for evaluating the therapeutic approach with norepinephrine in hyperkalaemia.  相似文献   
90.
Membrane damage caused by the non-specific fungal toxin fusaric acid was less on pretreated than on control leaves when tobacco leaves were pretreated with anti-senescence plant hormones, such as kinetin, benzyladenine or the anti-ozonant N-[2-(2-oxo-1-imidazolidinyl)]ethyl-N'-phenylurea. Similarly, the necrosis caused by mercuric chloride was reduced by the above anti-senescence agents. In addition, in in vitro tests, leaves from selected paraquat-tolerant tobacco plants were less sensitive to Alternaria alternata (Fr) Keissler infection than those of the control paraquat-sensitive tobacco leaves. Paraquat-tolerant Conyza canadensis (L) Cronq weeds naturally selected in vineyards in Hungary showed similar inhibition of senescence to paraquat-tolerant tobacco, expressed as more green leaves and slower development. In accordance with this, the paraquat-tolerant Conyza leaves remained almost symptomless, while paraquat-sensitive plants showed severe symptoms after infection with Botrytis cinerea Pers. Oxidative burst (accumulation of hydrogen peroxide) was attenuated in TMV-infected leaves of Xanthi-nc tobacco as a result of treatment with salicylic acid or in leaves where systemic acquired resistance (SAR) had been induced by a previous TMV infection. Accordingly, superoxide dismutase (SOD) activity was higher in Xanthi tobacco leaves with SAR than without SAR. However, in NahG tobacco, in which SAR cannot develop, there was no augmentation of SOD activity. All the above data support the significance of delayed senescence and antioxidants in the resistance of plants to biotic and abiotic necrosis-inducing agents.  相似文献   
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