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31.
El Amin Yousif Raddad 《New Forests》2007,34(3):207-222
The genetic variation in seed weight, seed number per kg and seedling traits was compared among eight Acacia senegal provenances originating from the clay plain (east) and sand plains (west) of the gum belt in Sudan. The main objective of
this study was to identify germplasm sources of A. senegal that have a good seed germination capacity and seedling traits suitable for reforestation in the clay-soil part of the dryland
gum belt in the Blue Nile region in Sudan. A specific objective was to tentatively explore the adaptive strategy of A. senegal populations. Seventeen-week-old seedlings were planted in the field at spacing of 3 m × 3 m, giving 100 trees per plot and
replication; within a randomized complete block design with four replications. The experimental site was in the clay plain
region. Seed variables showed significant differences. Clay plain provenances showed considerable variation in seed weight
and seed number. They had the smallest seed weight but the highest seed number, while the sand (western) provenances had the
largest seed weight but lowest seed number. Seedling branch number, root length, root to shoot ratio and shoot dry weight
differed significantly among the provenances 12 weeks after germination. Clay provenances had the highest branch number and
shoot dry weight but the shortest roots and lowest root to shoot ratio. This was interpreted as showing better adaptation
to the site in these local provenances in comparison to those originating from the western sandy soil regions. High positive
correlations were observed between seedling variables, such as root nodule and branch numbers; this could be used for early
selection. The variation was greater between provenance groups than within them, suggesting that especially selection among
groups would yield genetic gain. 相似文献
32.
Effect of Mediterranean saltbush (Atriplex halimus) ensilaging with two developed enzyme cocktails on feed intake,nutrient digestibility and ruminal fermentation in sheep 下载免费PDF全文
Haidy Alsersy Abdelfattah Z. M. Salem Borhami E. Borhami Jaime Olivares Hany M. Gado Maria D. Mariezcurrena Mohamed H. Yacuot Ahmed E. Kholif Mounir El‐Adawy Saul R. Hernandez 《Animal Science Journal》2015,86(1):51-58
The aim of this study was to assess the effects of feeding Atriplex halimus (AH) silage treated with two developed enzyme cocktails to sheep on feed intake, nutrient digestibility and ruminal fermentation. The AH silage was treated without or with 2 L of ZAD1® or ZAD2®/1000 kg with 5% molasses and ensiled for 30 days. Barley grain (300 g/head/day) was fed as an energy supplement once daily at 10.00 hours and AH silage with or without enzyme treatment was offered ad libitum to animals twice daily at 09.00 and 16.00 hours. Sheep were fed on four experimental forage diets comprised of AH silage and barley (D1), AH silage treated with ZAD1® and barley (D2), AH silage treated with ZAD2® and barley (D3) and AH silage treated with a combination of ZAD1® and ZAD2® (1:1) and barley (D4). Ensiling AH with enzymes reduced its contents of neutral detergent fiber and acid detergent fiber. The dry matter intake of AH of D2, D3 and D4 decreased (P < 0.001) as compared to D1. However, enzyme‐treated diets had greater total digestible nutrients intake (P < 0.001) as compared to D1. The nutrients digestibility for D2, D3 and D4 were higher than those for D1 (P < 0.001), and were higher for D3 as compared to both D2 and D4. Sheep fed on D3 had highest (P < 0.001) ruminal total volatile fatty acids concentration, ammonia nitrogen concentration and microbial protein yield. It could be concluded that AH silage treated with ZAD1® or ZAD2® improved digestibility and rumen fermentation in sheep. 相似文献
33.
Analysis of genomic mutation and immunohistochemistry of platelet‐derived growth factor receptors in canine vascular tumours 下载免费PDF全文
S. Abou Asa T. Mori K. Maruo A. Khater A. El‐sawak E. Abd el‐Aziz T. Yanai H. Sakai 《Veterinary and comparative oncology》2015,13(3):237-245
We examined whether mutation of the platelet‐derived growth factor receptor protein tyrosine kinase (PDGFR)‐α and PDGFR‐β genes contributes to their overexpression in canine vascular tumours. Genomic sequences of trans‐ or juxtamembrane regions of PDGFR‐α and PDGFR‐β were analysed with immunohistochemical staining and polymerase chain reaction‐direct sequencing using DNA from paraffin‐embedded neoplastic tissues of 27 hemangiosarcomas (HSAs) and 20 hemangiomas (HAs). Immunohistochemically, 75% of the HA cases were positive for PDGFR‐α and almost most of the HA cases were negative for PDGFR‐β. Of the HSA cases, 55.6% were negative for PDGFR‐α and 63% were strongly positive for PDGFR‐β. Among the HA cases, 1 missense mutation was detected in PDGFR‐α exon 18 and 1 in PDGFR‐β exon 17. Two HSA cases had missense mutations in exon 14 and 1 in exon 17 of PDGFR‐β. Thus, genomic mutation of trans‐ or juxtamembrane regions of PDGFRs was not the main mechanism driving the activation of receptors in HSA and HA. 相似文献
34.
Sana Hireche Omar Bouaziz Djahida Djenna Sabrina Boussena Rachida Aimeur Rachid Kabouia El Hacène Bererhi 《Tropical animal health and production》2014,46(2):467-473
A cross-sectional study was carried out to estimate prevalence of Chlamydophila spp. antibodies and to investigate risk factors associated with chlamydial infection in 552 ewes between March 2011 and January 2012 in the province of Constantine. Anti-Chlamydophila antibodies were detected using an indirect enzyme-linked immunosorbent assay kit in 24.5 % of examined sera. Of the herds, 70.4 % had at least one seropositive animal. A pretested structured questionnaire was administered in order to collect information on individual animal health and herd management practices. Chi-square analysis and multivariable logistic regression model were used to identify risk factors related to Chlamydophila seropositivity. Univariable analysis revealed 17 variables with p?<?0.25 that were offered to the multivariable logistic regression model which in turn identified 12–23 months age group (OR?=?5.903, 95 % CI (OR)?=?1.690; 20.618) and not using disinfectants (OR?=?2.099, 95 % CI (OR)?=?1.314; 8.065) as risk factors for Chlamydophila spp. seropositivity. Moreover, occurrence of stillbirth problem (OR?=?3.682, 95 % CI (OR)?=?1.825; 7.430) and 5–10 % mortality rate in young lambs (OR?=?2.584, 95 % CI (OR)?=?1.058; 6.310) were significantly associated with seropositivity to Chlamydophila spp. On the other hand, availability of veterinary service was identified as a protective factor (OR?=?0.161, 95 % CI (OR)?=?0.051; 0.511). 相似文献
35.
Stéphane Kroemer Farid El Garch Delphine Galland Jean-Luc Petit Frédérique Woehrle Henri-Jean Boulouis 《Comparative immunology, microbiology and infectious diseases》2014
A monitoring program of the pre-treatment susceptibility of clinical isolates of bacteria from diseased dogs and cats was active between the years 2002 and 2009. Susceptibility of each isolated strain to a panel of nine antibiotics (amoxicillin/clavulanic acid, ampicillin, penicillin, clindamycin, doxycycline, enrofloxacin, marbofloxacin, trimethoprim and trimethoprim/sulfamethoxazole) was assessed. The Minimum Inhibitory Concentration (MIC) of marbofloxacin was also determined by a standardized microdilution technique following CLSI recommendations. In total, 1857 bacterial strains were collected throughout Europe from cases of otitis, respiratory, urinary and dermatological infections. Although bacterial susceptibility varied for each of the antibiotics within the panel, patterns of susceptibility were similar to those described in the literature for comparable time periods and geographical areas. With a clinical resistance varying from 0 to 14.48% against the isolated strains, marbofloxacin susceptibility was very high and remains an effective antibiotic for the treatment of otitis, urinary, respiratory and dermatological infections in companion animals. 相似文献
36.
This study was designed to study the effect of short‐term supplementation with rumen‐protected fat during the late luteal phase on reproduction and metabolism of sheep during breeding season. Seventy‐six ewes (Rahmani, Barki and Awassi × Barki) were allocated to two groups considering genotype: the control ewes (C‐group) received a maintenance diet, and the fat‐supplemented ewes (F‐group) received the maintenance diet plus 50 g/head/day of rumen‐ protected fat (Megalac) for 9 days during which oestrus was synchronized. The latter had been accomplished using double intramuscular injection of prostaglandin F2α (PGF2α) 11 days apart. Ovarian activity, serum concentration of cholesterol, glucose, insulin and reproductive performance variables were recorded. Data were analysed considering treatment (group) and genotype. Supplementation had positive effects on the overall mean serum concentrations of cholesterol (p < 0.05), glucose (p < 0.05) on day 6 of nutritional treatment and insulin (p = 0.07) on day 8. Fat supplementation did not affect the total number of follicles, follicle populations and ovulation rate. However, fat‐supplemented Rahmani ewes tended to have higher ovulation rate compared with other breeds (treatment × breed interaction, p = 0.06). Treatment also did not affect the mean concentration of serum estradiol or progesterone. Supplemented ewes had higher conception (p = 0.06) and lambing rates (p < 0.05) compared with control. In conclusion, short‐term supplementation with rumen‐protected fat as a source of energy around breeding time improved metabolism, conception and lambing rates of ewes without effects on steroidogenic capacity and ovarian activity being apparent. 相似文献
37.
Gamal O. El Naggar George John Mahmoud A. Rezk Waheed Elwan Mohammed Yehia 《Aquaculture (Amsterdam, Netherlands)》2006,261(3):904-907
The development of a reliable methodology for spawning of African catfish, Clarias gariepinus without the use of hormone injections would greatly improve the prospects of aquaculture in Africa. Earlier work has shown that it is possible to produce C. gariepinus fingerlings by subjecting the broodfish to a physical stress of reduced water depth and/or increased temperature. The hypothesis that C. gariepinus could be induced to spawn through a combined physical stress of lowered water level and increased stocking density was tested in concrete tanks. Three water levels (25, 50 and 75 cm) and three stocking densities (2, 4 and 6 pairs of broodfish at a 1:1 sex ratio in each hapa) were tested. Water depth in the tanks and brood fish density in the hapas affected spawning success. The percentage of spawning females was significantly higher when broodfish were stocked at 2 and 4 pairs in each hapa at water levels of 25 cm or 50 cm. There was no significant difference in spawning response between the 25 and 50 cm depths while a significant difference was seen between the 75 cm and both 25 and 50 cm depths. The results indicate optimum levels and densities for enhancing spawning success in C. gariepinus. 相似文献
38.
Ahmad Asoodeh Leyla Haghighi Jamashidkhan Chamani Mohamad Amin Ansari-Ogholbeyk Zahra Mojallal-Tabatabaei Milad Lagzian 《Journal of Cereal Science》2014
The present study was carried out to characterize ACE inhibitory peptides which are released from the trypsin hydrolysate of wheat gluten protein. In silico proteolitic digestion of a high molecular weight glutenin subunit was performed. Among the resultant fragments, four peptides were selected for chemical synthesis based on the chemoinformatics studies and docking properties. The ACE inhibitory activity and kinetic parameters of the most important peptides were determined. Molecular docking simulation was also performed to predict the sites on ACE in which these peptides bind and displayed inhibition mechanisms. Two peptide sequences of IPALLKR (P4) and AQQLAAQLPAMCR (P6) showed higher ACE inhibitory activity among peptide collection. The IC50 values of P6 and P4 were 43 ± 1.3 μM and 68 ± 2.8 μM, respectively. P6 peptide was proved to be a more potent ACE inhibitor than P4 peptide. Lineweaver-Burk plots revealed that P6 and P4 behaved as non-competitive and competitive ACE inhibitors, respectively. The simulations showed that P4 bound to the active site region. Conversely, P6 bound to the N-terminus entrance of substrate tunnel and obstructed the substrate access into the catalytic site. Overall, the results showed that these peptides would be considered as a model for discovering new bio-compatible ACE inhibitors. 相似文献
39.
Riccardo A. A. Muzzarelli Mohamad El Mehtedi Monica Mattioli-Belmonte 《Marine drugs》2014,12(11):5468-5502
The present review article is intended to direct attention to the technological advances made in the 2010–2014 quinquennium for the isolation and manufacture of nanofibrillar chitin and chitosan. Otherwise called nanocrystals or whiskers, n-chitin and n-chitosan are obtained either by mechanical chitin disassembly and fibrillation optionally assisted by sonication, or by e-spinning of solutions of polysaccharides often accompanied by poly(ethylene oxide) or poly(caprolactone). The biomedical areas where n-chitin may find applications include hemostasis and wound healing, regeneration of tissues such as joints and bones, cell culture, antimicrobial agents, and dermal protection. The biomedical applications of n-chitosan include epithelial tissue regeneration, bone and dental tissue regeneration, as well as protection against bacteria, fungi and viruses. It has been found that the nano size enhances the performances of chitins and chitosans in all cases considered, with no exceptions. Biotechnological approaches will boost the applications of the said safe, eco-friendly and benign nanomaterials not only in these fields, but also for biosensors and in targeted drug delivery areas. 相似文献
40.
Shaharudin Mohamad Azimi Zaki Noorhariza Mohd Saleh Mohd Nazre Mohd Noor Normah Midin Mohd Razik 《Genetic Resources and Crop Evolution》2022,69(7):2291-2299
Genetic Resources and Crop Evolution - Mangosteen (Garcinia mangostana var. mangostana) is an obligate apomictic species which does not require a fertilization process to produce seeds. The absence... 相似文献