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1.
Chickens were given daily injections of cyproterone acetate (CA) and the effects on plasma corticosterone, bodyweight, weights of the adrenals and lymphoid organs, numbers of circulating peripheral blood lymphocytes and their proliferation in the presence of lectins, concanavalin A (Con A) and phytohaemagglutinin (PHA), were investigated. Five daily doses of 10 or 30 mg CA kg-1 bodyweight each week over a three-week period caused a decrease in weight gain and a reduction in the relative weights of the bursa and thymus but not the spleen. There was a small decrease in the adrenals after treatment with 10 mg CA kg-1. When daily injections of CA were given over a seven-day period doses of 6 and 10 mg CA kg-1 bodyweight caused a significant (P less than 0.05) decrease in plasma corticosterone concentration after four days. However, after eight daily injections of CA a single injection of corticotrophin (10 iu ACTH kg-1) increased circulating corticosterone indicating CA had not completely blocked adrenal synthesis. CA had no effect on numbers of circulating peripheral blood lymphocytes or their ability to proliferate in the presence of Con A or PHA. The results indicate that CA is effective in lowering circulating corticosterone in the fowl but this did not affect the numbers or responsiveness of peripheral blood lymphocytes.  相似文献   
2.
This experiment was designed to investigate and compare the egg production, fertility, hatchability and immune responses of some local developed Egyptian chicken strains under high ambient temperatures. A total of 108 (26 weeks old) laying hens of Matrouh, Silver Montazah, Mandarah and Inshas (9 hens × 3 replicates × 4 strains) were used to evaluate the impact of thermal stress (24-34ºC) during summer season (June, July and August) on egg production, fertility, hatchability and immune responses. The obtained results revealed that final body weight (FBW/g) and body weight change (BWC/g) among different chicken strains were not affected. The daily feed consumption (FC/g) and feed conversion ratio (FCR) for Silver Montazah and Inshas strains were significantly (p ≤ .05) higher than those of Matrouh and Mandarah strains. The mean egg production (EP/%) and egg mass (EM) for Silver Montazah and Inshas strains were significantly (p ≤ .05) higher than those of Matrouh and Mandarah strains. The highest percentages of hatchability of total eggs (HTE) and fertile eggs (HFE) were recorded in Inshas chickens, while the lowest value was recorded in Mandarah chickens. Also, the highest embryonic mortalities (p ≤ .05) and lowest chick weight at hatch (CWH/g) were recorded in Mandarah chickens compared with the other strains. The highest values for antibody titres against phytohemagglutinin-P (PHA-P) were recorded in Mandarah chickens, while the least values were recorded in Inshas chickens.  相似文献   
3.
The lipids metabolism of tomato and bean plants during biological control of wilt pathogens (Fusarium oxysporum f.sp.lycopersici andF. oxysporum f.sp.phaseoli, respectively) byBacillus subtilis was investigated. The interaction of wilt pathogens with both tomato and bean caused an imbalance and drastic reduction in total lipids, triacylglycerol, sterol and all phospholipd fractions except phosphatidic acid. The application of a formulated biocontrol agent,B. subtilis, eliminated the detrimental effect of both wilt pathogens and consequently prevented catabolism of lipid fractions in both tomato and bean. Moreover, the changes in the lipid fractions as a sensitive monitor for biocontrol of wilt diseases suggest a positive correlation between the application ofB. subtilis and improvement in the host metabolism towards anabolism. http://www.phytoparasitica.org posting Sept. 20, 2006.  相似文献   
4.
The employment of formulateBacillus subtilis as a biocontrol agent successfully controlledFusarium oxysporum f.sp.lycopersici within tomato seedlings (in vivo). B. subtilis was able to proted cortex and vascular tissues of tomato against progression of the wilt pathogen. No changes were observed in tomato tissues due to application ofB. subtilis except for hypertrophy and elongation of cortex tissues, which indicates the production of plant growth hormones byB. subtilis.  相似文献   
5.
40% lactic acid was sprayed 3 times into each of two bee colonies. The rate of infestation was determined, before beginning the experiment and after each of the applications. The treatments showed a mean percentage reduction in the brood infestation byVarroa of 76,7% in the first colony and 85,2% in the second. These data indicate that it is possible to control the Varroasis by means of lactic acid successfully and without side effects.  相似文献   
6.
The present investigation reports the novel synthesis of CoWO4 nanoparticles@silk fiber under ultrasound irradiation. The effect of temperature, power of ultrasound irradiation and sequential dipping steps in growth of the CoWO4 particles were studied. Results show a decrease in the particles size as the temperature and power of irradiation decreased. The fibers containing CoWO4 nanoparticles were tested for their antibacterial efficacy against E. coli and S. aureus and were found to possess significant antibacterial activity. The results show the CoWO4 nanoparticles@silk with strongest fluorescence characteristics can be obtained in this method. The physicochemical properties of the nanoparticles were determined by X-ray diffraction (XRD), scanning electron microscopy (SEM) and fluorescence spectroscopy.  相似文献   
7.
A full-length cDNA of an immunogenic protein was cloned from a cDNA library of the local Egyptian cattle tick Boophilus annulatus. Antibodies raised against B. annulatus larval proteins were used to screen a cDNA expression library. A 936bp cloned fragment was sequenced and showed an open reading frame of 516bp encoding a protein of 171 amino acids. Comparison of the deduced amino acid sequence with protein data bank revealed that the sequence is related to a sequence isolated from the hard tick Haemaphysalis qinghaiensis (Hq05). Southern blot analysis of B. annulatus genomic DNA showed that the cloned cDNA hybridized to double bands per restriction digest, suggesting that the cloned cDNA is a double copy gene. Amino acid analysis of the cloned gene revealed the presence of two casein kinase II phosphorylation sites in the N-terminal domain suggesting that this molecule may be involved in the signal transduction or gene expression pathways. RT-PCR and northern blotting revealed the presence of two isoforms of the Ba05 gene in salivary glands and in the 3-day-old eggs. The cloned gene without the signal peptide, was expressed in Escherichia coli under T7 promotor of pET-30b vector, and purified under denaturation conditions. The purified protein appeared as a single band on 12% SDS-PAGE with a molecular weight around 22.8kDa including the histidine tag of the vector. Antibodies raised against the purified molecule were used to detect the B. annulatus homologue to the Hq05 gene in whole tick, larvae and gut protein extracts. Immunoblotting revealed the presence of this molecule Ba05 only in whole tick and larval protein extracts and not in the gut protein extract. Using the same antibodies, homologues to the Ba05 gene were detected in other tick species as Hyalomma dromedarii and Rhipicephalus sp. but not in Ornithodoros moubata.  相似文献   
8.
This study was conducted to evaluate the effects of dietary taurine on growth performance and feed utilization of Nile tilapia (Oreochromis niloticus) larvae. Four plant protein‐based, isonitrogenous (400 g kg?1 protein), isoenergetic (19 MJ kg?1) diets supplemented with four taurine concentrations (0.0, 5.0, 10.0 and 15.0 g kg?1; designated as T0, T0.5, T1 and T1.5, respectively) were prepared. The diets were fed to triplicate groups of fish larvae (0.024 g average body weight), to apparent satiation, three times per day for 60 days. Larval growth rates and feed utilization efficiency were significantly improved with increasing supplemental taurine up to 10 g kg?1 and decreased with further taurine supplementation. The quadratic regression analyses indicated that the maximum larval performance occurred at about 9.7 g kg?1 of total dietary taurine. Fish survival was significantly lower at 15 g kg?1 dietary taurine than at other taurine levels. Body protein significantly increased, while body moisture and ash decreased, with increasing dietary taurine up to 10 g kg?1 and decreased with further taurine supplementation to 15 g kg?1. Body lipid was not significantly affected by dietary taurine concentration. A number of body amino acids (tryptophan, arginine, histidine, leucine, isoleucine, valine, alanine, glycine, threonine and taurine) significantly increased with increasing supplemental taurine up to 10 g kg?1 and then decreased with further increase in dietary taurine levels. The rest of body amino acids were not significantly affected by dietary taurine. The present results suggest that about 9.7 g kg?1 dietary taurine is required for optimum performance of Nile tilapia larvae fed soybean meal‐based diets.  相似文献   
9.
A fractional model of Bioheat equation for describing quantitatively the thermal responses of skin tissue under sinusoidal heat flux conditions on skin surface is given. Laplace transform technique is used to obtain the solution in a closed form. The resulting formulation is applied to one‐dimensional application to investigate the temperature distribution in skin with instantaneous surface heating for different cases. According to the numerical results and its graphs, conclusion about the fractional bioheat transfer equation has been constructed. Sensitivity analysis is performed to explore the thermal effects of various control parameters on tissue temperature. The comparisons are made with the results obtained in the case of the absence of time‐fractional order. © 2016 Japanese Society of Animal Science  相似文献   
10.
The current study was explored to examine the impacts of dietary inclusion of mixture of black (BPO) and red pepper (RPO) oils as growth promoters on growth, carcass, blood haematology, serum chemistry, immunity and antioxidative status of New Zealand White rabbits (NZW). A number total of 100 5‐week‐old NZW growing weaned rabbits were randomly allocated into four treatment groups in a complete randomized experiment. The dietary treatment groups were as follows: control: basal diet; BRP0.5: basal diet + 0.25 g BPO + 0.25 g RPO/kg diet; BRP1.0: basal diet + 0.50 g BPO + 0.50 g RPO/kg diet; and BRP1.5: basal diet + 0.75 g BPO + 0.75 g RPO/kg diet. Rabbits fed the highest level of BRP mixture were the heaviest, while the control rabbits were the lightest. During 5–9 weeks of age, a gradual improvement in feed conversion ratio (FCR) was noticed with increasing BRP level. The control group excelled all BRP groups regarding the majority of blood haematological parameters. Liver function was better in rabbits fed BRP enriched diets than the control. A gradual depression (p < 0.05 or 0.01) in serum lipids regardless high‐density lipoprotein (HDL) were recorded with elevating BRP level in the diet. The supplementation of BRP mixture enhanced the immune function and serum superoxide dismutase (SOD) activities and depressed serum malondialdehyde (MDA) in comparison with control. It could be concluded that dietary BRP mixture can affect some of growth traits, improve the immunity and antioxidant parameters, lower lipid profile and lipid peroxidation. Based on the study results, the recommended level of BRP mixture is 1.5 g/kg diet.  相似文献   
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