Plant communities and reproductive phenology in mountainous regions of northern Libya

Within the semi-desert landscape of northern Libya, two sub-humid escarpments occur: Al-Akhdar in the east and Nafusa(Jabal Al-Gharbi) in the west. This study compares plant communities in the two regions, which are along an elevation gradient, in terms of species composition and diversity, frequency of different Raunkiaer life forms, and reproductive phenology. The two regions differed in species composition and life-form frequency between regions and between elevation zones within each region. Patterns were associated with the lower rainfall and lower moisture-holding capacity of soils at Nafusa,resulting in more xeric conditions. Only 13% of species were shared between the two regional landscapes. Species diversity, life-form frequency, and duration of the flowering–fruiting phenophase were all affected by elevation above sea level. The duration of flowering and fruiting in spring and fall was associated with environmental conditions, although there were different thresholds in the two regions. There was both a spring and fall episode of flowering at Nafusa, but only spring flowering at Al-Akhdar. It is anticipated that there will be a gradual shift of plant communities to higher elevations and loss of certain sensitive species in response to ongoing climate change.     

Some biological effects of white mustard oil,Brassica alba against the cotton leafworm,Spodoptera littoralis (Boisd.)

Effects of white mustard oil on egg deposition and on egg masses viability ofSpodoptera littoralis were determined. The bioactivity of different concetrations of oil emulsion on moths was assayed in semifield trial. Spraying of 2.5% of the oil on cotton plants caused reduction in egg laying. The moths laid only 7% of their egg masses and the percentage of repellency was 89.4%. The moth longevity was significantly reduced and the female ones were more affected by the treatment than males.At 2.5% conc., egg masses of different ages (24, 48 and 72 h old) were highly affected and the reductions were 66.6, 45 and 92%, respectively compared to the control. In general, the older eggs had the higher susceptibility to the tested concentrations in comparison to newly deposited eggs.     

Dietary Echinacea purpurea administration enhanced egg laying performance,serum lipid profile,antioxidant status and semen quality in duck breeders during summer season

This work investigated the outcomes of dietary administration of Echinacea purpurea (EP) powder to breeder ducks on productive and reproductive performance during summer season. Sudani ducks (320 birds) of 32-weeks-old (240 females and 80 males) were randomly allocated into four collections (body weight; 1850 ± 15.2 g for females and 2960.0 ± 40.5 g for males). The primary collection consumed the basal diet without supplementation and was deliberated as control. The other three collections were fed the basal diet supplemented with 2.5, 5.00 and 7.5 g EP/kg diet, correspondingly. Egg number and mass, laying rate, feed consumption and feed conversion ratio (FCR) were significantly changed by dietary EP levels. Drakes fed EP-supplemented diets had higher ejaculate volume, sperms concentration and live sperms (%) as well as lower dead sperms (%) than the control group. Eggs laid by ducks fed diet supplemented with 2.5 g/kg had the greatest fertility and hatchability percentages, followed by those fed 5.0 g EP/kg. Ducks fed different EP diets had higher values of haemoglobin, RBCs, WBCs and lymphocytes, lower values of heterophils percentage and lower H/L ratio than the control. All serum constituents were significantly changed by dietary EP supplementation, except of total protein and Alanine Aminotransferase (ALT) enzyme. Conclusively, dietary EP supplementation at 2.5 g/kg had beneficial effects on productive and reproductive performance as well as lipid profile and antioxidant status and economically valued in breeder ducks under summer conditions.     

Effects of increasing dietary rye levels on physicochemical characteristics of digesta and its impact on stomach emptying as well as the formation of ‘doughballs’ in stomachs of young pigs

Despite quite similar contents of starch and crude fibre of wheat and rye, the unique non-starch-polysaccharide fraction of rye (e.g. high levels of arabinoxylans and fructans) might have an impact on physicochemical properties of the digesta in pigs. Forty pigs (age: 46.8 ± 5.28 days; bodyweight: 16.1 ± 4.13 kg) were divided into four treatment groups. During four weeks, the pigs received diets consisting of wheat and/or rye, barley, soy, potato protein and a mineral supplement. The sum of wheat and rye was 69% in all diets, whereby the compound feed of each group was characterized by a different ratio (%) of wheat/rye (69/0; 46/23; 23/46; 0/69, respectively). In the stomach, ‘doughballs’ occurred more frequently with increasing dietary rye levels (9/10; 69% rye). With higher DM content and extract-viscosity of gastric digesta, the stomach emptying tended to be retarded in rye groups. Compared to the control group (69% wheat), maximum dietary rye levels (69%) resulted in significantly higher concentrations of lactic acid in digesta of the stomach and small intestine. With increasing lactic acid concentrations, the pH tended to be lower in small intestinal digesta. With an intensified formation of lactic acid, effects against Gram-negative bacteria, for example Salmonella, can be expected. Moreover, because of higher viscosity and the retarded stomach emptying, there could be advantages of including rye in compound feeds when a longer lasting satiety is intended, for example when feeding pregnant sows (regularly fed restrictively).     

Physiological and biochemical studies on chilling-injury of banana

Storage of banana fruits at low temperature was unsuccessful due to chilling-injury. Titratable acidity and respiration of banana fruits remained lower at 5°C than at room temperature and accompanied the prevention of ripening and chilling-injury. Dopamine (3,4-dihydroxyphenylethylamine) was the only major phenolic constituent in banana peel; low temperature might induce its oxidation to dark coloured substances.     

Recovery of Ralstonia solanacearum from canal water in traditional potato-growing areas of Egypt but not from designated Pest-Free Areas (PFAs)

Surveys over three seasons of irrigation, drainage and artesian well water throughout the major potato-growing areas of Egypt indicated that Ralstonia solanacearum bv. 2 race 3 (phylotype II sequevar 1), cause of potato brown rot, was limited to the canals of the traditional potato-growing areas in the Nile Delta region, with positive findings more commonly associated with the network of smaller irrigation canals flowing through potato-growing areas. Pathogen populations in the canals of the Delta (~100–200 cfu l^?1) were generally variable throughout the year with presence linked to potato cultivation in the immediate area. The pathogen was not detected in irrigation or drainage water associated with potato cultivation in the newly reclaimed desert areas (designated as Pest-Free Areas, PFAs) or in the main branches of the Nile upstream from these areas. In vitro studies showed that temperature and microbial activity were the main factors affecting survival of the pathogen in canal water. In experiments at temperatures of 4, 15, 28 and 35°C, survival was longest at 15°C and shortest at 35°C. Survival at 4 and 28°C tended to be intermediate between these extremes as was survival when the bacterium was grown at fluctuating temperatures. Aeration, solarisation and pH variation between 4 and 9 appeared to have little effect on survival. Survival in autoclaved or filter-sterilised canal water was longer than in untreated water irrespective of other factors with survival times exceeding 300 days at 15°C in some experiments. Evidence is presented indicating that survival in water-saturated sediment may be longer than in the overlying water suggesting that sediment may provide a protective niche for the pathogen in some circumstances. The maximum survival time in non-sterile Egyptian canal water at high inoculum pressure was estimated to be up to 300 days at optimum temperature for survival (15–30°C) suggesting the potential for long-distance spread in Egyptian surface waters from sources of contamination.     

Effect of ofloxacin on theophylline pharmacokinetics at clinical dosage in dogs

We examined the effects of ofloxacin (OFX) and norfloxacin (NFX) on theophylline (TP) pharmacokinetics in dogs. OFX, as a noncompetitive and mechanism-based inhibitor, and NFX, as a noncompetitive inhibitor, were orally administered (5 mg/kg) for a single dose or multiple doses (12 hourly for 3 days). TP (5 mg/kg, i.v) was injected at 2 h after the final dose of the fluoroquinolones (FQs). The same dose of TP was injected (i.v) 3 weeks before the start of FQs treatment for control. Multiple doses of OFX significantly reduced the total body clearance (Cl(B)) of TP from 0.117 to 0.085 L/h/kg, although a single dose did not change it. Neither a single dose nor multiple doses of NFX changed the TP pharmacokinetics. Plasma NFX concentrations increased after multiple doses. Those of OFX also increased but were still two orders of magnitude below the K(i) for noncompetitive inhibition of CYP1A in dogs. Time-dependent reduction in Cl(B) of TP suggests that mechanism-based inhibition of OFX was the major mode to decrease Cl(B) of TP. The mechanism-based inhibition may result in substantial inhibition of CYP1A activities in clinical conditions.     

Parasitoids belonging to the genus Aphytis Howard (Hymenoptera: Aphelinidae) in Citrus orchards in Lattakia,Syria

A survey of the common Aphytis spp. Howard (Hymenoptera: Aphelinidae) parasitoids was carried out at four citrus orchards (which were not treated with chemical pesticides) in AL‐Hanade, Stamo, Tarjano and Hmaiem in Lattakia Governorate from September 2010 to September 2011. Six parasitoid species of the genus Aphytis were reared from living armoured scale insects isolated in four states. They were Aphytis lepidosaphes (Compere), Aphytis lingnanesis (Compere), Aphytis chrysomphali (Mercet), Aphytis melinus (DeBach), Aphytis maculicornis (Masi) and Aphytis hispanicus (Mercet).