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111.
In vivo and in vitro protein digestibility in juvenile bagrid catfish Mystus nemurus (Cuvier and Valenciennes 1840) fed soybean meal‐based diets
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In vivo and in vitro protein digestibility of 0% to 60% soybean meal protein (SBM) substitution from fishmeal protein was conducted for bagrid catfish Mystus nemurus juveniles. Seven experimental diets containing 35% protein and 15% lipid were fed to bagrid catfish to determine the in vivo protein digestibility. In vitro methods were determined using pH stat, pH shift, spectrophotometric assay and sodium dodecyle sulphate polyacrylamide gel electrophoresis (SDS‐PAGE) with different enzyme mixtures (crude intestinal extract of bagrid catfish, Lazo 1‐enzyme, Hsu 3‐enzyme, Saterlee 4‐enzyme). In vivo and in vitro protein digestibility decreased with increased SBM protein substitution with highest tolerance level of 10% (in vivo). pH stat and pH drop methods showed the highest degree of hydrolysis (DH) and relative protein digestibility (RPD) using Saterlee 4‐enzyme system. However, pH stat method showed highest correlations (r2 = 0.9263) with the in vivo results using crude intestinal enzyme extract compared to other enzyme systems. The highest correlation of the in vitro methods using crude intestinal enzyme extracts of bagrid catfish was determined using spectrophotometric assay (r2 = 0.9284) followed by pH stat (r2 = 0.9263), SDS‐PAGE (r2 = 0.8348) and pH drop (r2 = 0.6777). All the in vitro methods tested are suitable to rapidly determine protein digestibility for bagrid catfish except for pH drop. 相似文献
112.
A field experiment was conducted using Ceranock bait station, "attract and kill" system to combat Mediterranean fruit fly, Ceratitis capitata, in apricot orchards, Central of lraq during the 2013 field season. Control program was implemented in three orchards of mixed apricot varieties. Ceranock traps were hung in each tree of two separate orchards. Delta and McPhail traps were used to monitor Medfly population density in each treated and control orchards. Results indicated that Medfly activity in apricot orchards started during the last week of April coincided with the beginning of maturity for fruits of early varieties. The total of trapped insects in monitoring traps after one week of Ceranock application were 0, 1 and 31 adults for the 1st, 2nd and the control orchards, respectively. Three weeks later and on, the number of trapped adults started to increase dramatically. At the end of apricot season and after 45 days of Ceranock trap application, the number of trapped insects in monitoring traps reached 110, 111 and 2,349 adults/week, respectively, for the 1st, 2nd and 3rd orchard. The use of Ceranock traps reduced Medfly population density by 86%-97%. The percentage of fruit injuries in early maturing varieties were 0.75%, 1% and 34% for the 1st, 2nd and control orchards, respectively. While, late varieties were 2% and 3% for 1st and 2nd orchards, and 69% for the control. The percentage of reduction in fruit damages reached to 95% and 97%, respectively in the 1st and 2nd orchard. The results of this study demonstrate clearly the efficacy of Ceranock bait station, "attract and kill" system as a control measure for Medfly in apricot orchards. 相似文献
113.
Purpose
Hydroxyl ion release by maize (Zea mays L.) roots under acidic conditions was investigated with a view to develop a bioremediation method for ameliorating acid soils in tropical and subtropical regions.Materials and methods
Two hydroponic culture experiments and one pot experiment were conducted: pH, nitrogen state, and rhizobox condition, which investigated the effects of different nitrogen forms on hydroxyl release by maize roots under acidic conditions.Results and discussion
The pH of the culture solution increased as culture time rose. The gradient of change increased with rising NO3 ?/NH4 + molar ratios. Maize roots released more hydroxyl ions at pH 4.0 than at pH 5.0. The amount of hydroxyl ions released by maize roots at a constant pH was greater than those at a nonconstant pH. Application of calcium nitrate reduced exchangeable acidity and increased the pH in an Ultisol rhizosphere, compared with bulk soil. The increasing magnitude of soil pH was greater at higher doses of N. The absorption of NO3 ?–N increased as the NO3 ?/NH4 + molar ratios rose, which was responsible for hydroxyl ion release and pH increases in culture solutions and rhizosphere.Conclusions
Root-induced alkalization in the rhizosphere resulting from nitrate absorption by maize plants can be used to ameliorate acidic Ultisols. 相似文献114.
Mohammed Piro Abdelaziz Benjouad Abdelghafor Karom Ahmed NabichNoureddine Benbihi Khalid El Allali Mohammed Machmoum Lahoussine Ouragh 《Journal of Equine Veterinary Science》2011,31(11):618-624
A total of 17 microsatellite deoxyribonucleic acid loci used routinely for horse parentage control were used to evaluate genetic diversity among normal Arabian horses and severe combined immunodeficiency (SCID) carrier Arabian horses (ArS) and normal Arab-Barb horses and SCID carrier Arab-Barb horses (ArbeS). On the basis of the genotype of 186 horses, mean allelic diversity was estimated as 6.82, 5.53, and 6.7059 in normal Arabian horses, ArS, and for both groups of Arab-Barb horses, respectively. Five specific alleles were observed in ArS and ArbeS, with one common with ArS at HMS6, whereas five alleles common between ArS and ArbeS had a high frequency. Expected and observed heterozygosity showed great heterogeneity in the population studied and were similar or higher when compared with other studies on Arabian horses. Coefficient of gene differentiation Gst of Nei associated with Nei’s genetic distance and multivariate correspondence analysis indicated a possible differentiation between the studied populations when analyzed separately according to breed. Probability of assignment of a horse to a specific group was assessed using a full and partial Bayesian approach. In all, 80.6% of Arab horses and 78.2% of Arab-Barb horses were assigned properly with a partial Bayesian test, which provided better results than the full one. These findings will be useful for identification of SCID carrier horses by using the microsatellite deoxyribonucleic acid loci used routinely for horse parentage control in our laboratory. 相似文献
115.
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117.
Aboragah Ahmed Embaby Mohammed Günal Mevlüt AbuGhazaleh Amer 《Tropical animal health and production》2020,52(2):771-776
Tropical Animal Health and Production - The main objective of this research was to evaluate the effects of chemical treatment and sonication (ultrasound) processing on the fiber composition and... 相似文献
118.
Awad Walid S. El-Sayed Amr A. Mohammed Faten F. Bakry Noha M. Abdou Nadra-Elwgoud M. I. Kamel Mohamed S. 《Tropical animal health and production》2020,52(6):3173-3185
Tropical Animal Health and Production - Escherichia coli field isolates from calves were characterized and categorized into the most significant diarrheagenic pathotypes using polymerase chain... 相似文献
119.
Razan F. Al-Qadri Ehab A. Abu-Basha Mohammed M. Ababneh Zuhair Bani Ismail Nasir M. Idkaidek 《Journal of veterinary pharmacology and therapeutics》2020,43(4):339-346
The objectives of this study were to determine the pharmacokinetics of toltrazuril and its metabolites in pregnant and nonpregnant ewes following a single oral dose and to determine the plasma concentrations of these compounds in milk, allantoic fluid, and newborn plasma. Eighteen healthy ewes were randomly divided into three groups (n = 6 each): pregnant ewes at 12–13 weeks of gestation (group A), nonpregnant ewes (group B), and pregnant ewes at 1–2 weeks before expected lambing date (group C). Ewes in all groups received a single oral dose of toltrazuril at 20 mg/kg body weight. In groups A and B, blood samples were collected at 1, 3, 5, 7, 9, 12, 15, 18 hr, every 6 hr to day 3, every 12 hr to day 7 and thereafter every 24 hr to day 14 post-toltrazuril administration. In group C, parturition was induced 24–36 hr after toltrazuril administration then milk, allantoic fluid, and newborn plasma samples were collected immediately after birth. Drug metabolites were assayed using ultra high-performance liquid chromatography–ultraviolet detection method (UHPLC-UV). The maximum concentration (Cmax), area under the plasma concentration-time curve (AUC0–t), AUC to 24 and 48 hr (AUC0–24), and (AUC0–48) were significantly higher in pregnant ewes. Longer apparent half-life (T1/2), significantly higher apparent volume of distribution (Vd/F) and total clearance (Cl/F) were observed in nonpregnant ewes. The time to maximum plasma concentration (Tmax), mean residence time (MRT) and elimination rate constant (Kel) were similar in both groups. The AUC0–24 and AUC0–48 were significantly higher in nonpregnant ewes. The AUC0–t was significantly higher in pregnant ones. The ratio of plasma toltrazuril concentrations in ewes and toltrazuril concentrations in newborn lambs' plasma, allantoic fluid, and milk were 68%, 2.3%, and 5.3%, respectively. Results of this study showed that toltrazuril is well absorbed after a single oral dose in ewes with widespread distribution in different body tissues. 相似文献
120.
Fawzia S. Al‐Yousif Mohammed H. Al‐Whaibi Sayeda O. El‐Hirweris 《Journal of plant nutrition》2013,36(6):1037-1052
Date palm (Phoenix dactylifera L. cv Khedhri) and sorghum (sorghum Sudan grass hybrid cv sugar Graze 11) plants were grown in vermiculite in a controlled environment and watered with a nutrient solution containing eight different concentrations of boron (B) (0 to 500 ppm), six months for date palm and four weeks for sorghum. The chlorophyll (Chl) content of the seedlings increased significantly with low concentrations of B for both date palm and sorghum, but no further significant increases were observed at higher concentrations. Generally, there was a positive correlation between B and calcium (Ca) content in the tissues of both seedlings when B concentrations were increased in the media. A negative correlation was found between B concentration in the media and the tissue content of phenolic compounds and the activity of some enzymes, such as polyphenol oxidase, IAA‐oxidase and phenylalanine ammonia‐lyase in the tissue, while there was a positive correlation in the case of peroxidase. Ribonucleic acid (RNA) increased significantly in date palm with the increase of B in the medium, but for sorghum, the increase occurred at 10–100 ppm and decreased at 300 and 500 ppm B in the media. 相似文献