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1.
Adventitious roots of Korean mountain ginseng (Panax ginseng C.A. Meyer) were processed by using forced air drying methodology at 30, 50 and 70 °C for 1, 3, 5, 10 and 20 h with objective of developing suitable processing/drying technique. Drying of adventitious roots at 50 °C for 10 h was found suitable as desirable moisture content (3.13 g water/dry matter i.e. 10%) could be reached with dried roots. Roots which were dried by such treatment were also possessing higher amount of ginsenosides (1.5 mg g−1 DW triols, 15.9 mg g−1 DW diols and 17.4 mg g−1 DW of total ginsenosides) and phenolics. Adventitious roots were also processed by using far infrared and freeze drying methods and results revealed that forced air drying method is superior to far infrared and freeze drying methods.  相似文献   

2.
Nine multiparous and 12 primiparous cows were fed diets containing an anionic salt supplement and moderate Ca (0.99%) or high Ca (1.50%) concentrations for 21 d prepartum to determine the effects of dietary Ca concentration on serum and urine electrolytes and on postpartum intake and milk yield. Blood samples were collected during 21 to 1 d prepartum, 0 to 2 d postpartum, and 3 to 21 d postpartum. Dietary cation-anion difference (DCAD) for prepartum diets was approximately −6 mEq/100 g of dry matter (Na + K − Cl − S). Immediately postpartum, cows were fed diets with positive DCAD with greater than 1.00% Ca concentration. Mean serum Ca concentrations 21 to 1 d prepartum, 0 to 2 d postpartum, and 3 to 21 d postpartum were 9.62, 8.41, and 9.38 mg/dL. There were no treatment effects on serum Ca concentration. Mean serum Ca concentration was higher for primiparous than multiparous cows (9.34 vs. 8.93 mg/dL) for the trial and at calving (8.77 vs. 8.13 mg/dL). Mean serum HCO3 and urinary pH, respectively, were 20.32 mEq/L and 5.67 prepartum, 25.82 mEq/L and 7.62 at calving, and 26.08 mEq/L and 8.25 postpartum. No differences due to treatment were observed for serum and urinary concentrations of HCO3, pH, Mg, Na, K, and Cl. Milk yield was similar for 0.99 and 1.50% Ca treatments (22.8 and 20.7 kg/d). Diets containing 0.99 or 1.5% Ca maintained serum Ca at adequate levels around parturition and resulted in similar dry matter intake and postpartum milk yield.  相似文献   

3.
Fructose, glucose and sucrose, as the major soluble sugars and citric and malic acids, as the major organic acids, were identified and determined in kale (Brassica oleraceae L. var. acephala DC., black cabbage) leaves. Fructose was the predominant sugar (2011 mg 100 g−1 dry wt) identified, followed by glucose (1056 mg 100 g−1 dry wt) and sucrose (894 mg 100 g−1 dry wt). The contents of citric and malic acids were at 2213 and 151 mg 100 g−1 dry wt in the leaves. The 16:0, 18:2n − 6 and 18:3n − 3 fatty acids were the most abundant fatty acids in the leaves. Considering the level of these fatty acids, 18:3n − 3 was found to be the highest (85.3 μg g−1 dry wt), contributing 54.0% of the total fatty acid content. Linoleic acid (18:2n − 6), being the second most abundant fatty acid was present at 18.6 μg g−1 dry wt, contributing 11.8% of the total fatty acid content. In the seed oil of kale, 22:1n − 9 was the most abundant fatty acid (4198 μg g−1 dry wt, 45.7%), with 18:2n − 6 (1199 μg g−1 dry wt, 12.3%) and 18:1n − 9 (1408 μg g−1 dry wt, 14.8%) being the second next most abundant fatty acids. The most abundant amino acid was glutamic acid (Glu) which was present at 33.2 mg g−1 dry wt. Aspartic acid, which was the second most abundant amino acid, was present at 27.6 mg g−1 dry wt and accounted for 10.2% of the total amino acid content of kale leaf. The amino acid content was assessed by comparing the percentages of the essential amino acids in kale leaf versus those of a World Health Organization (WHO) standard protein. The protein of kale leaf compares well with that of the WHO standard. Only one amino acid, lysine, had a score that fell below 100%; the lysine score of kale leaf was 95%. This study attempts to contribute to knowledge of the nutritional properties of the plant. These results may be useful for the evaluation of dietary information.  相似文献   

4.
The concentrations of flavonols (kaempeferol, quercetin, myricetin) were determined in 22 plant materials (9 vegetables, 5 fruits, and 8 medicinal plant organs). The materials were extracted with acidified methanol (methanol/HCl, 100:1, v/v) and analyzed by reverse phase high-performance liquid chromatographic (RP-HPLC) with UV detection. The total flavonols contents varied significantly (P < 0.05) among vegetables, fruits and medicinal plant organs ranged from 0 to 1720.5, 459.9 to 3575.4, and 2.42 to 6125.6 mg kg−1 of dry matter, respectively. Among vegetables, spinach and cauliflower exhibited the highest amounts of flavonols (1720.5 and 1603.9 mg kg−1, respectively), however, no flavonols were detected in garlic. Within fruits, highest level of flavonols was observed in strawberry (3575.4 mg kg−1), whereas, the lowest in apple fruit (459.9 mg kg−1). Of the medicinal plant organs, moringa and aloe vera leaves contained the highest contents of flavonols (6125.6 and 1636.04 mg kg−1), respectively, whereas, lowest was present in barks (2.42–274.07 mg kg−1). Overall, leafy green vegetables, soft fruits and medicinal plant leaves exhibited higher levels of flavonols.  相似文献   

5.
A study was conducted to evaluate the effects of a direct-fed microbial (M) and dietary glycerol (G) on milk yield, efficiency of yield, and nutrient digestibility during hot weather. Sixty Holstein cows averaging 120 d in milk (DIM) and 36.2 kg/d of milk were used in a 12-wk 2 × 2 factorial design trial from June through September 2008. Cows were fed a common diet during the 2-wk standardization period and were blocked by milk yield, DIM, parity, and dry matter intake. Diets were based on corn and ryegrass silages and balanced to be isocaloric and isonitrogenous. Treatments included a negative control (M− or G−), 4 × 109 cfu/head of a combination of Lactobacillus acidophilus NP51 and Propionibacterium freudenreichii NP24 (M+), control plus 400 g/h per day of 99% pure food-grade glycerol (G+), and 4 × 109 cfu/h per day of a combination of Lactobacillus acidophilus NP51 and Propionibacterium freudenreichii NP24 plus 400 g/h per day of 99% pure food-grade glycerol (MG++). No interactions were observed between direct-fed microbials and dietary glycerol in the study except on apparent nutrient digestibility. No differences were observed in dry matter intake, which averaged 22.7, 23.1, 23.4, and 22.9 for M−, G−, M+, and G+, respectively. Milk yield was increased for M+ compared with M− at 34.1 and 31.7 kg/d, but G+ had no effect on yield. No treatment effect was noted for milk fat percentage or milk protein percentage among diets. Milk protein yield was higher for M+ compared with M− at 0.93 versus 0.87 kg/d. Energy-corrected milk was improved for the M+ versus M− groups at 33.5 and 31.6 kg/d, respectively. No differences in respiratory rate, skin temperature, body temperature, or concentrations of serum glucose or urea N were observed among treatments. Improvement in apparent digestibility was observed with M+ and G+ compared with M−/G− in this experiment. The addition of a direct-fed microbial alone improved milk and protein yield, energy-corrected milk, and apparent digestibility of crude protein, neutral detergent fiber, and acid detergent fiber, and the inclusion of glycerol (G+) had a positive effect on apparent dry matter and acid detergent fiber digestibility compared with M−/G−. The addition of a direct-fed microbial and dietary glycerol may improve yield and digestibility for cows subject to heat stress.  相似文献   

6.
Hay to reduce dietary cation-anion difference for dry dairy cows   总被引:1,自引:0,他引:1  
Timothy grass has a lower dietary cation-anion difference [DCAD = (Na + K) - (Cl + S)] than other cool-season grass species. Growing timothy on low-K soils and fertilizing it with CaCl2 could further decrease its DCAD. The objective of this study was to evaluate the effects of feeding low-DCAD timothy hay on dry dairy cows. Six nonpregnant and nonlactating cows were used in a replicated 3 × 3 Latin square. Treatments were as follows: 1) control diet (control; DCAD = 296 mEq/kg of dry matter); 2) low-DCAD diet based on low-DCAD timothy hay (L-HAY; DCAD = - 24 mEq/kg of dry matter); and 3) low-DCAD diet using HCl (L-HCl; DCAD = - 19 mEq/kg of dry matter). Decreasing DCAD with L-HAY had no effect on dry matter intake (11.8 kg/d) or dry matter digestibility (71.5%). Urine pH decreased from 8.21 to 5.89 when L-HAY was fed instead of the control. Blood parameters that decreased with L-HAY were base excess (− 0.4 vs. 3.8 mM) and HCO3 (23 vs. 27 mM), and blood parameters that increased were Ca2+ (5.3 vs. 5.1 mg/dL), Cl (30.5 vs. 29.5 mg/dL), and Na+ (60.8 vs. 60.1 mg/dL). Compared with the control, L-HAY resulted in more Ca in urine (13.4 vs. 1.2 g/d). Comparing L-HAY with L-HCl, cow dry matter intake tended to be higher (11.5 vs. 9.8 kg/d), and blood pH was higher (7.37 vs. 7.31). Urine pH; total dry matter; Ca, K, P, and Mg apparent absorption; and Ca, K, Na, Cl, S, P, and Mg apparent retention were similar. Absorption as a percentage of intake of Na and Cl was lower for L-HAY as compared with L-HCl. In an EDTA-challenge test, cows fed L-HAY regained their initial level of blood Ca2+ twice as quickly as the control treatment (339 vs. 708 min); there were no differences between L-HAY and L-HCl. This experiment confirms that feeding low-DCAD hay is an effective means of decreasing the DCAD of rations and obtaining a metabolic response in dry dairy cows.  相似文献   

7.
Daily pen dry matter intakes (DMI, n = 9,275) were collected over a 28-mo period at the University of Wisconsin's Integrated Dairy Research Facility. Heifers were housed in pens containing 8 Holstein or Holstein × Jersey crossbred heifers/pen. Heifer diets were formulated to energy and protein requirement twice monthly, with feed intake, dietary nutrient density, and ambient temperature recorded daily. Heifers were weighed at 60-d intervals, and mean pen body weights (BW) were estimated for each day between the weigh dates using the interval average daily gain as a regression coefficient. Prediction of heifer DMI was evaluated using the equations of NRC (2001), Quigley et al. (1986), or alternative random effects mixed models or nonlinear exponential models. The effects of breed, BW, temperature and neutral detergent fiber deviation (NDFdv) were considered as independent variables. Holstein and crossbred heifer DMI was predicted with reasonable precision [standard error (SE) < 0.86 kg/d], by the NRC (2001) or Quigley et al. (1986) equations, but heifer DMI was over- or underpredicted for heifers >500 kg, respectively. Improved heifer DMI prediction equations were achieved with exponential models. For Holsteins (SE = 0.71 kg/d), the prediction equation was: DMI (kg/d) = 15.79 × [1 - e(−0.00210 × BW)] − 0.0820 × NDFdv, where NDFdv = (dietary neutral detergent fiber as a % of dry matter) - {22.07 + [0.08714 × BW] - [0.00007383 × (BW)2]}. For crossbred heifers (SE = 0.60 kg/d), the prediction equation was: DMI (kg/d) = 13.48 × [1 - e(−0.00271 × BW)] - 0.0824 × NDFdv where NDFdv = (dietary neutral detergent fiber as a % of dry matter) - {23.11 + [0.07968 × BW] - [0.00006252 × (BW)2]}. Alternative exponential DMI model equations when dietary neutral detergent fiber is unknown were also developed. The Holstein DMI equation (SE = 0.73 kg/d) was: DMI (kg/d) = 15.36 × [1 - e(−0.00220 × BW)], and the crossbred DMI equation (SE = 0.81 kg/d) was: DMI (kg/d) = 12.91 × [1 - e(−0.00295 × BW)].  相似文献   

8.
Mango slices (1 and 2 mm thickness) were dried by using the Refractance Window™ (RW) technique with the water bath temperature set at 92 °C. Drying kinetics, water activity, and color change were determined and compared with those obtained by drying the slices in a tray dryer at 62 °C and an air velocity of 0.52 m/s. At 1 h, moisture contents of 0.013 (for 1 mm sample) and 0.048 (for 2 mm sample) kg water/kg dry solid for RW, and 0.966 (for 1 mm sample) and 3.614 (for 2 mm sample) kg water/kg dry solid for tray drying were obtained and water activity was less than 0.5 for RW and close to 0.97 for tray drying. The tray dryer took 4 h to reach results similar to those of RW at 1 h. The samples dried by RW exhibited diffusivities of 4.40 × 10−10 (for 1 mm sample) and 1.56 × 10−9 (for 2 mm sample) m2/s, which are larger than those exhibited by the air-dried samples, 2.08 × 10−11 (for 1 mm sample) and 6.83 × 10−11 (for 2 mm sample) m2/s.  相似文献   

9.
Cell walls were isolated from flesh and skin of five plum varieties corresponding to three species (Prunus domestica L., Prunus salicina Lindl. and Prunus insititia Lindl.) using the alcohol-insoluble solids (AIS) procedure. Yields varied from 83 to 114 g kg−1 dry weight in the flesh and from 192 to 361 g kg−1 dry weight in the skins. Their main sugars were uronic acid (224–322 mg g−1 AIS), cellulosic glucose (139–170 mg g−1 AIS), galactose and arabinose. Galactose and arabinose ratio were variable between the varieties. The degrees of methylation were high (62–84).  相似文献   

10.
A rapid liquid chromatographic method for glufosinate analysis in maize samples after derivatisation has been developed. The labelled glufosinate was separated on a Kromasil C18 column (250 mm × 4.6 mm, 5 μm) and UV detection was applied at 360 nm. The optimisation of derivatisation conditions and the influence of different ion-pair reagents on the separation were discussed. The method linearity correlation coefficient was 0.9998 in concentrations ranging from 0.1 to 20 mg L−1. The level of quantification was set to 0.02 mg kg−1, and reached pesticide EU-MRLs for glufosinate in the maize samples. The proposed method was applied to the quantitative determination of glufosinate in samples with recoveries of 98.0–100.5% and RSDs of 2.13–4.13%.  相似文献   

11.
Twenty-four multiparous Holstein cows (775 ± 24 kg body weight; 3.4 ± 0.11 body condition score) were used in a randomized complete block design experiment to determine the impact of increased ruminal butyrate from the fermentation of lactose on metabolism and lactation. Dietary treatments were either a corn-based control diet (CON) or a diet containing lactose at 15.7% of diet dry matter (LAC). Experimental diets were fed from 21 d before expected calving through 21 d in milk (DIM). Blood was sampled at −21, −14, −7, −2, 2, 7, 14, and 21 DIM, rumen fluid at −21, −7, and 7 DIM, and liver tissue via biopsy at 7 and 14 DIM. Pre- and postpartum dry matter intake (DMI) through 28 DIM averaged 12.8 and 17.7 kg/d, respectively, and did not differ between treatments; however, cows fed LAC did not exhibit a prepartum decrease in DMI. Milk yield was unaffected by treatments and averaged 45.7 kg/d during the first 70 DIM. Plasma glucose, insulin, and non-esterified fatty acids were not affected by dietary treatments. Feeding LAC increased the ruminal proportion of butyrate both pre- (11.3 vs. 9.2 ± 0.45%) and postpartum (13.0 vs. 10.3 ± 0.67%). Likewise, circulating plasma β-hydroxybutyrate was increased both pre- (6.1 vs. 4.2 ± 0.31 mg/dL) and postpartum (14.6 vs. 8.34 ± 1.7 mg/dL) when feeding LAC compared with CON. Liver lipid content was decreased (8.6. vs. 14.7 ± 1.5% of wet weight) in cows fed LAC relative to those fed CON, whereas liver glycogen was not affected by dietary treatments. Feeding lactose to transition dairy cows increased the proportion of butyrate in the rumen and β-hydroxybutyrate in plasma and decreased liver lipid but did not affect lactation performance.  相似文献   

12.
The contents of As, Cd, Cr, Cu, Fe, Hg, Mg, Mn, Ni, Pb, and Zn in eleven fruiting bodies of Boletus tomentipes were determined. The results showed the values of the studied elements decreased in the order: Mg (208–279 mg kg−1) > Fe (106–137 mg kg−1) > Mn (29.5–46.8. mg kg−1) > Zn (18.7–23.1 mg kg−1), > Cu (11.4–15.8 mg kg−1) > Cr (3.36–4.78 mg kg−1) > Pb (1.38–3.88 mg kg−1) > Ni (1.68–3.01 mg kg−1) > Cd (0.16–0.32 mg kg−1) > As (0.10–0.24 mg kg−1) > Hg (<0.06 mg kg−1).  相似文献   

13.
Ten popular species of both edible and medicinal Korean mushrooms were analysed for their free amino acids and disaccharides. The average total free amino acid concentration was 120.79 mg g−1 in edible mushrooms and 61.47 mg g−1 in medicinal mushrooms, respectively. The average total of free amino acids for all mushrooms, edible mushrooms and medicinal mushrooms was 91.13 mg g−1. Agaricus blazei (227.00 mg g−1) showed the highest concentration of total free amino acids; on the other hand, Inonotus obliquus (2.00 mg g−1) showed the lowest concentration among the 10 species of mushrooms. The average total carbohydrates concentration was 46.67 mg g−1 in the 10 species of mushrooms, where the edible mushrooms contained 66.68 mg g−1 and the medicinal mushrooms contained 26.65 mg g−1. The carbohydrates constituents of the 10 mushroom species were mainly mannose (36.23%), glucose (34.70%), and xylose (16.83%).  相似文献   

14.
Growth and digestibility were examined for heifers limit fed high- (HC; 60%) and low-concentrate (LC; 20%) diets with or without yeast culture (YC) addition in 2 experiments. A third experiment was undertaken to monitor first-lactation production of heifers limit fed HC or LC diets. In experiment 1, 32 Holstein heifers were individually fed at controlled intakes for 133 d to maintain a targeted average daily gain of 0.80 kg/d for all 4 treatments [HC; LC with and without Saccharomyces cerevisiae; Yea-Sacc1026 (Alltech Inc., Nicholasville, KY), 1 g/kg as fed]. Targeted average daily gain was achieved for all treatments during the individual feeding period (0.80 ± 0.01 kg/d). Average dry matter intake needed to maintain constant gain was slightly reduced for HC and YC treatments. Reduced dry matter intake and similar targeted average daily gain resulted in a tendency for improved feed efficiency of HC-fed heifers. Skeletal measurements and targeted average daily gain were not affected by concentrate level or YC. The objective of experiment 2 was to elucidate effects of concentrate level and YC on nutrient digestibility. Four young (284.35 ± 4.51 d) and 4 older (410.28 ± 2.14 d) heifers were allocated to the 4 treatments used in experiment 1. Heifers fed the HC diet had increased dry matter digestibility (75.67 vs.72.96 ± 0.72%), and YC addition increased dry matter digestibility (74.97 vs. 73.65 ± 0.71%). Intake of N and apparent N digestibility were similar for all treatments. High-concentrate diets and YC addition decreased wet and dry matter output of feces. Urine excretion was not different; therefore, total manure output was lower for HC-fed heifers as compared with LC-fed heifers. Results suggest that HC diets can improve feed efficiency without affecting growth when limit fed to dairy heifers. Yeast culture increased dry matter digestibility in HC- and LC-fed heifers; HC diets were more digestible and reduced fecal output, with YC enhancing this effect. In experiment 3, heifers from experiment 1 were group fed the same diets (HC or LC) without YC until parturition, and milk production was measured through 154 d of lactation. Group-fed average daily gain was not different between treatments (HC = 1.11 vs. LC = 1.04 kg/d, SE = ±0.06 kg/d). Heifers fed the HC and LC diets calved at 23.50 and 23.79 ± 0.50 mo, respectively. Peak milk was lower and there was a tendency for reduced daily milk and protein yield for primiparous cows fed HC diets from 8 mo of age to the dry/prefresh period (long term), but predicted yields of milk and components were similar in the first 154 d of lactation.  相似文献   

15.
Six genotypes of sweet potato commercially available in Taiwan, including TNG57, TNG66, TNG68, TYY1, RP and WP, were used as samples in this study of the effects of steaming and kneading with pre-steaming treatments on the antioxidant components and antioxidant properties of methanolic extracts. Steam treatment increased the total phenols contents of all genotypes (2–13 times), flavonoids content of RP (1.3 times) and anthocyanins contents of RP and WP (5–6 times). Steam treatment also increased the reducing power and scavenging DPPH radical effect of sweet potato flours. For the methanolic extracts of steamed and kneaded flours, reducing powers were 0.02–1.70 at 5.0 mg ml−1 and the scavenging effects on DPPH radicals were 19–92% at 2.5 mg ml−1. Both showed the order of RP > WP > TYY1 and TNG66 > TNG57 and TNG68. However, the chelating effect of the six genotypes at 1.0 mg ml−1 ranged from 50% to 73%. Contents of total phenols, flavonoids, and anthocyanins of sweet potato flours were significantly positively correlated with the reducing power and scavenging DPPH radical effects. After steaming and kneading treatments, RP showed the highest increase in the contents of total phenols, flavonoids and anthocyanins among the six genotypes studied.  相似文献   

16.
This study examined the ability of near infrared reflectance spectroscopy (NIRS) to estimate the concentration of polyunsaturated fatty acids and their biohydrogenation products in the subcutaneous fat of beef cows fed flaxseed. Subcutaneous fat samples at the 12th rib of 62 cows were stored at − 80 °C, thawed, scanned over a NIR spectral range from 400 to 2498 nm at 31 °C and 2 °C, and subsequently analysed for fatty acid composition. Best NIRS calibrations were with samples at 31 °C, showing high predictability for most of the n−3 (R2: 0.81-0.86; RMSECV: 0.11-1.56 mg g− 1 fat) and linolenic acid biohydrogenation products such as conjugated linolenic acids, conjugated linoleic acids (CLA), non-CLA dienes and trans-monounsaturated fatty acids with R2 (RMSECV, mg g− 1 fat) of 0.85-0.85 (0.16-0.37), 0.84-0.90 (0.21-2.58), 0.90 (5.49) and 0.84-0.90 (4.24-8.83), respectively. NIRS could discriminate 100% of subcutaneous fat samples from beef cows fed diets with and without flaxseed.  相似文献   

17.
A normal-phase HPLC method for analysis of carotenes, tocopherols and tocotrienols has been developed and validated. In this work we presented a modification to the official AOCS method for analysis of tocols which allowed simultaneous quantification of the three groups of compounds, including carotenes. Analytes were separated using a gradient mobile phase (hexane and isopropanol) and with a gradient flow rate (1–2 mL min−1). The column effluent was monitored by Photo Diode Array detector (PDA) set at 292 nm (tocols) and 455 nm (β-carotene) and by fluorescence detector set at an excitation wavelength of 290 and 330 nm emission. Inter- and intra-run accuracies and precision of the analytical method were better than ±15%. The lower limit of quantification was 5.0 mg L−1 for the tocols and 0.1 mg L−1 for carotenes. The method has been applied for the quantification of these compounds in Amazon oils.  相似文献   

18.
Hot water treatment was used to decaffeinate fresh tea leaf in the present study. Water temperature, extraction time and ratio of leaf to water had a statistically significant effect on the decaffeination. When fresh tea leaf was decaffeinated with a ratio of tea leaf to water of 1:20 (w/v) at 100 °C for 3 min, caffeine concentration was decreased from 23.7 to 4.0 mg g−1, while total tea catechins decreased from 134.5 to 127.6 mg g−1; 83% of caffeine was removed and 95% of total catechins was retained in the decaffeinated leaf. It is considered that the hot water treatment is a safe and inexpensive method for decaffeinating green tea. However, a large percentage of tea catechins was lost if rolled leaf and dry tea were decaffeinated by the hot water treatment and so the process is not suitable for processing black tea.  相似文献   

19.
Laboratory experiments were conducted to determine the efficacy of spinosad (a biopesticide), chlorpyrifos-methyl (an organophosphorus compound (OP)) and s-methoprene (a juvenile hormone analogue) applied alone and in binary combinations against five stored-grain beetles in wheat. There were three strains of Rhyzopertha dominica, and one strain each of Sitophilus oryzae, Tribolium castaneum, Oryzaephilus surinamensis and Cryptolestes ferrugineus. These strains were chosen to represent a range of possible resistant genotypes, exhibiting resistance to organophosphates, pyrethroids or methoprene. Treatments were applied at rates that are registered or likely to be registered in Australia. Adults were exposed to freshly treated wheat for 2 weeks, and the effects of treatments on mortality and reproduction were determined. No single protectant or protectant combination controlled all insect strains, based on the criterion of >99% reduction in the number of live F1 adults relative to the control. The most effective combinations were spinosad at 1 mg kg−1+chlorpyrifos-methyl at 10 mg kg−1 which controlled all strains except for OP-resistant O. surinamensis, and chlorpyrifos-methyl at 10 mg kg−1+s-methoprene at 0.6 mg kg−1 which controlled all strains except for methoprene-resistant R. dominica. The results of this study demonstrate the difficulty in Australia, and potentially other countries which use protectants, of finding protectant treatments to control a broad range of pest species in the face of resistance development.  相似文献   

20.
The concentrations of cadmium, cobalt, chromium, copper, iron, manganese, nickel, lead and zinc were determined by ICP-AES in muscles and livers of 12 fish species sampled from the Marmara, Aegean and Mediterranean seas of Turkey. Iron showed the highest levels in examined tissues of all fish species. Following Fe, Zn generally showed the second highest levels. Metal concentrations in edible parts of fish species were 0.02–0.37 mg kg−1 for cadmium, 0.04–0.41 mg kg−1 for cobalt, 0.04–1.75 mg kg−1 for chromium, 0.32–6.48  mg kg−1 for copper, 7.46–40.1 mg kg−1 for iron, 0.10–0.99  mg kg−1 for manganese, 0.02–3.97 mg kg−1 for nickel, 0.33–0.86 mg kg−1 for lead, 4.49–11.2 mg kg−1 for zinc, respectively. All metal concentrations in livers were higher than those in muscles. In some stations, cadmium and chromium concentrations in both muscles and livers, and lead levels in livers of the examined species were higher than permissible safety levels for human uses.  相似文献   

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