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61.
Critical concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), zinc (Zn), and manganese (Mn) with respect to dry matter yield end antagonistic and synergistic relationships among these nutrients were studied in which tomato (Lycopersicon esculentum L.) was grown in recirculating nutrient solution (NFT). Increments of nutrient elements in the nutrient solution increased the proportional rate of the corresponding nutrient elements. Increasing levels of N negatively correlated with plant P and positively correlated with Ca, Fe, and Zn. Iron and Mn contents of the plants were increased and N, K, Ca, and Mg were decreased as a function of P applied. Increases in K in the nutrient solution caused increases in the concentrations of K, N, P, and Zn, and decreases in the concentration of Ca and Fe. Applied Ca increased the concentrations of Ca and N, and decreased the concentrations of P, Mg, Fe, Zn, and Mn. Potassium, Ca, and Fe contents of the plants were decreased and Zn increased, while N, P, and Mn were not affected by the increasing levels of external Mg. Iron suppressed the plant Mg, Zn, and Mn contents. Synergism between Zn and Fe was seen, while P, K, Ca, Mg, and Mn contents were not affected by Zn levels. Potassium, Ca, Mg, and Fe were not responsive to applied Mn, however, N and P contents of the plants were decreased at the highest levels of Mn.  相似文献   
62.
In this study, an adaptive neuro fuzzy interface system (ANFIS) based predictor was designed to predict the physical properties of four almond types. Measurements of the dimensions, length, width and thickness were carried out for one hundred randomly selected samples of each type. With using these three major perpendicular dimensions, some physical parameters such as projected area, arithmetic mean diameter, geometric mean diameter, sphericity, surface area, volume, shape index and aspect ratio were estimated. In in a various Artificial Neural Network (ANN) structures, ANFIS structure which has given the best results was selected. The parameters analytically estimated and those predicted were given in the form of figures. The root mean-squared error (RMSE) was found to be 0.0001 which is quite low. ANFIS approach has given a superior outcome in the prediction of the Physical Properties of Almond Nuts.  相似文献   
63.

This study investigated the pharmacokinetics of pentoxifylline (PTX) and its 5-hydroxyhexyl metabolite (M-I) after single-dose intravenous (IV) administration (10 mg/kg) of PTX in six healthy cattle. The safety of PTX was evaluated by clinical observation and biochemical analysis. Plasma concentrations of PTX and M-I were simultaneously determined by reverse-phase high performance liquid chromatography. Pharmacokinetic parameters were calculated using non-compartmental methods. Salivation and discomfort were observed for 2 h following the drug administration. Serum direct bilirubin, total bilirubin, and phosphorus levels at 24 h following the drug administration were significantly different from the control values (0 h) (P?<?0.05). Pharmacokinetic variables of PTX were characterized by a short terminal elimination half-life (1.05?±?0.19 h), a large volume of distribution (6.30?±?1.76 L/kg), and high total body clearance (5.31?±?1.27 L/h/kg). The mean ratio between the area under the concentration-time curves of M-I and PTX was 1.34. These results indicate that single-dose administration of PTX at 10 mg/kg IV in cattle resulted in therapeutic concentrations similar to those observed in humans and horse. However, further studies are necessary to determine the safety and pharmacokinetics following repeated administrations of PTX.

  相似文献   
64.
Tropical Animal Health and Production - The primary objective of the present study was to assess the effects of vitamin and mineral premix (VMP) withdrawal from the diets 30 and 60&nbsp;days...  相似文献   
65.
为探索有效的杀灭蜱方法,减少蜱虫危害,选择新疆阿勒泰地区青河县查干郭勒乡蜱虫流行较严重的一家农户,开展了杀虫油剂和伊维菌素联合应用防控家畜蜱虫试验。试验分为杀虫油剂组、伊维菌素注射液组、杀虫油剂和伊维菌素注射液联合使用组和不用药的对照组。每组有50只不同年龄的牛、羊、马等家畜,其饲养管理、放牧条件、圈室条件都基本相同。杀虫油剂组、伊维菌素注射液组间隔1个月,同法同量进行2次用药;杀虫油剂和伊维菌素注射液联合使用组先使用杀虫油剂,1个月后注射伊维菌素注射液。用药后观察无蜱的维持时间和第1次用药90 d后仍发现蜱的试验动物数量,计算不同试验组的杀虫效果。结果显示,杀虫油剂组、伊维菌素注射液组、杀虫油剂和伊维菌素注射液联合使用组用药后的无蜱维持时间分别为70、60、90 d,预防效率分别为90%、86%、100%。结果表明,杀虫油剂和伊维菌素注射液联合使用,可起到最佳的蜱虫预防效果。  相似文献   
66.
67.
In this study, the effect of pine mistletoe (Viscum album subsp. austriacum) on basal area increment of Crimean pine and Scots pine was investigated. Dendrochronological data were collected from 223 (71 uninfected and 152 infected) Crimean pines and 195 (77 uninfected and 118 infected) Scots pines located in Kastamonu province of Turkey in 2014. Infected sample trees were classified as light, moderate or severe infection levels. Growth trends and basal area increment loses were compared between uninfected and infected trees for the periods of the last 10, 20 and 30 years. In addition, infection status of forest stands was investigated using temporary sample plots; 27 plots in Crimean pine stands and 26 plots in Scots pine. Results demonstrated that basal area increments were negatively affected by pine mistletoe for both species. Mean basal area increment losses of infected trees for the last decade were determined as 24% for Scots pine and 26% for Crimean pine. Basal area increment losses varied by infection levels (light, moderate and severe) as follows: 25%, 20% and 28% for Scots pines and 20%, 32% and 9% for Crimean pines. Scots pine stands were more severely infected by pine mistletoe than Crimean pine stands. There were negative correlations between number of infected trees and stand density for both species, while positive correlation was detected between the number of infected trees and mean diameter for Scots pine. The results of this study indicate that the pine mistletoe infection has negative effect on radial growth of Scots pine and Crimean pine trees. The results can be an important contribution to the forest management and protection activities in mistletoe-infected stands.  相似文献   
68.
We studied the effect of different food sources, infective juveniles of the entomopathogenic nematodes, Steinernema feltiae and Heterorhabditis bacteriophora (Rhabditida: Steinernematidae, Heterorhabditidae), and tissues from the insect larva, Polyphylla fullo (Coleoptera: Scarabaeidae) or Galleria mellonella (Lepidoptera: Pyralidae), on the development, reproduction and longevity of Sancassania polyphyllae (Acari: Acaridae). We showed that the immature mite stages - protonymph and tritonymph - could develop to the next developmental stage on living or sonicated (i.e., ruptured) S. feltiae or H. bacteriophora. However, the mite larval stage could only develop to the next developmental stage on sonicated infective juveniles of the nematodes. Subsequently, we demonstrated that S. polyphyllae completed development from protonymph to adult on live S. feltiae or H. bacteriophora, whereas all immature stages of S. polyphyllae completed their development from larva to adult on insect tissues. The total developmental period of S. polyphyllae that fed on insect tissues was significantly shorter than those that fed on live infective juveniles. The pre-oviposition, oviposition, and post-oviposition periods and female longevity were not significantly different among the food sources. The total and daily fecundity of S. polyphyllae feeding on P. fullo and G. mellonella was significantly higher than those feeding on S. feltiae and H. bacteriophora, although there was no significant difference observed between P. fullo and G. mellonella or between S. feltiae and H. bacteriophora. The net reproductive rate (R0) was highest (588.3♀/♀) when S. polyphyllae fed on P. fullo. The longest mean generation time (T0) occurred on H. bacteriophora (12.6 days) and the shortest occurred on P. fullo (10.5 days). S. polyphyllae, which fed on P. fullo (rm=0.61) and G. mellonella (rm=0.55) had the highest intrinsic rate of increase (rm) compared to mites that fed on S .feltiae (rm=0.45) and H. bacteriophora (rm=0.41).  相似文献   
69.
The objective of the present work was to evaluate the effects of three different rates of long chain n-3 polyunsaturated fatty acid (LC n-3 PUFA) on the sperm number of Astacus leptodactylus. The experiment was carried out with the four following treatments: control group (not supplemented LC n-3 PUFA), D1 (1 %), D2 (2 %) and D3 (3 %). The sperm number of A. leptodactylus was counted; the reproductive system was weighted; and the macroscopical analysis of the testes and vasa deferentia (DVD) were conducted. In addition, gonado-somatic index (GI) and testes index (TI) were also calculated. The results showed that there was a significant difference between the crayfish fed LC n-3 PUFA supplemented diets (D1, D2, D3) and control in mean sperm number (P < 0.05). The highest sperm number was found for the crayfish fed D3 (6.27 ± 0.14 × 108 sperm/distal vas deferens section). The results also showed that the reproductive system of the crayfish fed D3 and D2 was significantly heavier than that of the crayfish fed the control and D1 (P < 0.05). On the other hand, there was not a significant difference in the testes weight and vasa deferentia weight between the crayfish fed the control and D1, and between the crayfish fed D2 and D3 (P < 0.05). GI of the crayfish fed D3 and D2 was significantly higher than that of the crayfish fed control and D1 (P > 0.05), but there was not a significant difference in the TI of the crayfish fed control, D1, D2 and D3 (P > 0.05). In conclusion, diets containing different levels of LC n-3 PUFA significantly increase the sperm number of A. leptodactylus, and they are crucial for the production of higher number of sperm in this species.  相似文献   
70.
Blood and serum samples were taken from 481 horses, from a stud farm or a racecourse, and tested by microscopic examination of blood smears and cELISA for Theileria equi (T. equi) and Babesia caballi (B. caballi) infections. At the time of sampling, animals were also examined for tick infestations and clinical disease, which were not observed in any of the sampled horses. During the microscopic examination of thin blood smears, parasites were detected in the three horses from the racecourse. Overall seroprevalence of infection was detected as 18.50% (89 of 481 horses) by cELISA, with T. equi being significantly more prevalent than B. caballi. Of the 481 blood samples, 78 (16.21%) were serologically positive for T. equi and 4 (0.83%) were serologically positive for B. caballi. In addition, 7 (1.46%) samples were positive for both T. equi and B. caballi antibodies. Seropositivity rates in the racecourse horses were higher than those determined in the stud farm horses. The rates for T. equi, B. caballi and both species were 13.39, 0.52 and 0% in the horses from the stud farm and 27, 2 and 7% in the racecourse horses, respectively. These results indicate that equine piroplasmosis is more common in racehorses than studhorses and therefore it might be a serious concern in horses that participate to international races.  相似文献   
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