A Modified DMT-HFO Technique for Investigating the Kinetics of Phosphorus Desorption from Calcareous Soils and its Relationship with Maize Growth

In this research, phosphorus (P) desorption was investigated using DMT-HFO as an “infinite” sink for 10 calcareous soils over a period of 1–35 days and the kinetic data was related to soil properties and P uptake by maize (Zea mays L.). First- and second-order, and simple Elovich equations adequately described P desorption kinetics, however parabolic, exponential and zero order equations provided the best fits to the data. A systematic relationship exists between the second order rate parameter (k₂) and the clay content of the soils. There are positive relationships between P desorption rate constants (for zero order, Elovich and parabolic equations), and both dry matter and P content of maize shoots and also for roots. These relationships indicate that P desorption rate may be a limiting factor for maize growth in these soils. The DMT-HFO technique may be used to assess the long-term availability of P to plants.     

Expression of blood hepatocyte-derived microRNA-122 in canine multicentric lymphoma with hepatic involvement

Veterinary Research Communications - This study was performed to evaluate the hepatocyte-derived microRNA (miR)-122 as novel diagnostic biomarker in canine lymphoma. Fifteen dogs were enrolled in...     

Antioxidant capacities,phenolic compounds,carotenoids, and vitamin C contents of nectarine,peach, and plum cultivars from California

Genotypic variation in composition and antioxidant activity was evaluated using 25 cultivars, 5 each of white-flesh nectarines, yellow-flesh nectarines, white-flesh peaches, yellow-flesh peaches, and plums, at the ripe (ready-to-eat) stage. The ranges of total ascorbic acid (vitamin C) (in mg/100 g of fresh weight) were 5-14 (white-flesh nectarines), 6-8 (yellow-flesh nectarines), 6-9 (white-flesh peaches), 4-13 (yellow-flesh peaches), and 3-10 (plums). Total carotenoids concentrations (in microg/100 g of fresh weight) were 7-14 (white-flesh nectarines), 80-186 (yellow-flesh nectarines), 7-20 (white-flesh peaches), 71-210 (yellow-flesh peaches), and 70-260 (plums). Total phenolics (in mg/100 g of fresh weight) were 14-102 (white-flesh nectarines), 18-54 (yellow-flesh nectarines), 28-111 (white-flesh peaches), 21-61 (yellow-flesh peaches), and 42-109 (plums). The contributions of phenolic compounds to antioxidant activity were much greater than those of vitamin C and carotenoids. There was a strong correlation (0.93-0.96) between total phenolics and antioxidant activity of nectarines, peaches, and plums.     

Quality of testicular semen of the African catfish Clarias gariepinus (Burchell, 1822) and its relationship with fertilization and hatching success

Quality differences of testicular semen of the African catfish, Clarias gariepinus, and their influence on fertilization and hatching success were investigated. In accordance with an earlier study, two semen types of the African catfish were distinguished according to testicular maturity stage. Semen type I derived from males with white mature testes whereas type II semen derived from males with grey, partly mature testes. Semen volume, sperm cell concentration and seminal plasma pH was significantly higher in type I semen than in type II semen, while sperm motility was similar. Similar fertilization percentages were obtained with semen type I and semen type II. However, the hatching percentage was higher and the percentage of deformed hatched larvae was lower for type I semen. There were significant (P<0.01) positive correlations between sperm motility and fertilization percentage, seminal plasma pH and hatching percentage and a negative correlation between seminal plasma pH and percentage of deformed larvae. Therefore seminal plasma pH and sperm motility are useful to predict semen quality of the African catfish.     

Anesthetic Efficacy of Clove Oil,Propofol, 2‐Phenoxyethanol,and Ketamine Hydrochloride on Persian Sturgeon,Acipenser persicus,Juveniles

Anesthetics are commonly used in the aquaculture industry to reduce stress and prevent mortality of fish during transportation, handling, and surgical procedures. This study assessed the efficacy of four anesthetic agents (clove oil, propofol, 2‐phenoxyethanol [2‐PE], and ketamine hydrochloride) on Persian sturgeon, Acipenser persicus, juveniles. In addition, results of the first experiment were used to evaluate sedation concentrations suitable for transportation of Persian sturgeon. The concentrations of anesthetics or sedatives evaluated in the first experiment were: 25, 50, 75, and 100 mg/L for clove oil; 1, 1.25, 2.5, and 5 mg/L for propofol; 110, 330, 550, and 770 mg/L for 2‐PE; and 1250, 2500, 3750, and 5000 mg/L for ketamine hydrochloride. Results show significant reduction in time to anesthesia and significant increase in recovery time with increase in concentration of all anesthetics. The most clinically useful concentrations of anesthetics tested were between 25 and 50 mg/L for clove oil, less than 1 mg/L for propofol, 330 mg/L for 2‐PE, and none of the tested concentrations for ketamine hydrochloride. In the second experiment, juveniles were placed in low concentrations of anesthetic solutions for 24 h and survival assessed. The four anesthetics tested are suitable for light sedation during transportation of A. persicus juveniles. Results are helpful to scientists working with Persian sturgeon aquaculture and restocking programs.     

Effects of Pediococcus pentosaceus supplementation on growth performance,intestinal microflora and disease resistance of white shrimp,Litopenaeus vannamei

Litopenaeus vannamei is economically important shrimp species in worldwide aquaculture. This study was conducted to assess the effect of different levels of probiotic Pediococcus pentosaceus (PP) on growth performance, feed utilization, digestive enzyme activity, intestinal microflora count and body composition of L. vannamei. Four diets containing different concentrations [0 (PP0), 10⁶ (PPI), 10⁷ (PPII) and 10⁸ (PPIII) CFU/g] of PP were formulated. After 8 weeks feeding trial, the experimental shrimps were challenged with Vibrio anguillarum and noted the surveillance. At the end of the feeding trial, the obtained results revealed a significant increase (p < .05) in final body weight, final length, weight gain (WG), survival rate, protease and amylase activities, lactobacillus sp. and Bacillus sp. intestinal count, total haemocyte counts (THC) and lysozyme activity in PPIII group when compared with the other groups. Similarly, WG, amylase activity, Bacillus sp. count, THC and lysozyme activity were significantly enhanced in case of PPII compared to the control group (p < .05). Interestingly, FCR and Vibrio sp. counts were significantly decreased in case of PPIII group when compared to the other groups (p < .05). Also, significant level of surveillance was noted in the challenging test with V. anguillarum. These results suggested that the P. pentosaceus improved the growth performance, digestive enzyme activity, immunity and tolerance against V. anguillarum of L. vannamei.     

Modeling and Analysis of Mechanization Projects of Wheat Production by GERT Networks

In crop production systems,all operations such as seed bed preparation,etc.,must be accomplished on time,if yield reduction and low quality product are to be avoided.Therefore all operations in mechanized cropping projects require precise scheduling,planning and management.The basic approach in all scheduling techniques is to form a network of activities and events relationships that graphically portrays the sequential relations between the tasks in a project.Such a network would as a powerful tool available a farm manager to plan,schedule,monitor and control a project.Since GERT（Graphical Evaluation and Review Technique） networks have most of advantages associated with networks and available system analyst in exact evaluation of certain types of networks,in this research it was used and mechanized wheat production system was simulated,modeled and analyzed.Critical activities,events and path were determined.Results showed that the network model was able to answer any statistic questions concerning with the project.Network models,particularly GERT networks are increasingly powerful tool for modeling,scheduling,planning,controlling,and analyzing of agricultural mechanization projects.