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1.
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
2.
In a 14-week study, 1-year-old Aleppo pine seedlings were grownin two growth chambers. Seedlings were artificially hardenedby decreasing photoperiod and temperature. In each chamber halfof the seedlings were fertilized with nitrogen (8.4 mg seedling1).In order to determine the relative importance of the hardeningenvironment versus fertilization, each chamber was programmedto decrease night temperatures down to a low of 8 or 4°C.Chlorophyll fluorescence and frost hardiness was measured fivetimes during the experiment. A sample of seedlings from eachtreatment was exposed to an artificial frost at 5°Cand the freezing effects were assessed by measurements of chlorophyllfluorescence and visual evaluation of needle damage. Seedlingsincreased their frost hardiness during the experiment in allthe treatments but the ratio of variable to maximal chlorophyllfluorescence (Fv/Fm) measured before freezing did not vary duringthe experiment. This indicates that Aleppo pine maintains itsphotosynthetic ability during hardening in contrast to otherconiferous species from colder climates. The effect of nitrogenfertilization on frost hardiness was small in comparison withchamber effect. Nitrogen fertilization slightly delayed theacquisition of hardening in the coldest chamber. Seedlings inthe warmest chamber did not become fully resistant to 5°C,but in the coldest chamber, where night temperature reached4°C, all the seedlings were resistant to the frost. Severedamage caused by frost could be related to a rapid rise of minimalfluorescence (F0) but the best index of damage was the dropof Fv/Fm after freezing. 相似文献
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The recent decline of Mediterranean oak woodlands in SW Iberian Peninsula is related to insect pests which affect both cork oak (Quercus suber) and holm oak (Quercus rotundifolia). We identified twenty-six bird species as potential regular predators of twenty major pests by reviewing the diet of breeding, wintering and resident species in this ecosystem. Foraging guilds are strongly associated with predation at distinct stages of the pests’ life-cycle: ground-foragers prey on overwintering pupae and larvae of seed-borers, tree-foragers prey on eggs, larvae and pupae of defoliating and wood-boring pests, and aerial-sweepers prey on airborne imagines. Bird predation can cover the complete life-cycle of pest species because different species may be complementary due to a dissimilar exploitation of foraging niches and periods. Small generalist tree-foraging passerines are important pest predators given their high densities and widespread distribution in Mediterranean oak woodlands, but management practices can have a significant negative effect in their populations. 相似文献
6.
Jaime A. Ocampo-Hernández Patricia Tamez-Guerra Samuel Pineda Fernando Tamayo-Mejía Ariel Guzmán-Franco José I. Figueroa de la Rosa Ana Mabel Martínez 《Journal of pest science》2011,84(4):471-477
Entomopathogenic fungi represent excellent candidates for biological insecticides. Among the many entomopathogenic fungi, Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Clavicipitaceae) is one of the most promising species. Here, we report the results of infection studies performed using four B. bassiana native isolates (Bb37, Bb38, Bb40, and Bb45) compared with the commercial product Mycotrol® (strain GHA) on adult Mexican bean beetle Epilachna varivestis Mulsant (Coleoptera: Coccinellidae), one of the most important pests of bean production in Mexico. First, single concentration (1 × 108 conidia mL?1) assays were carried out using all isolates applied using an immersion method. Examinations at 10 days after inoculation indicated that isolates Bb37, Bb38, and Bb40 significantly reduced adult survival, causing 60–75% mortality compared to the commercial strain GHA (33%) and control (29%). Second, using two selected isolates (Bb37 and Bb40), the mean lethal concentration values (LC50) were estimated for third instar larvae and adult E. varivestis. The LC50 values for Bb37 and Bb40 isolates decreased 5.26-fold and 3.19-fold, respectively, in third instars compared with adults. However, such difference for Bb40 isolate was not significant. Finally, an experiment, to compare the median survival time (MST) values between third instar and adult E. varivestis, was conducted using Bb37 and Bb40 at 1 × 109 conidia mL?1. MST values were significantly reduced against larvae (87 and 100 h) compared with adults (130 and 134 h) by Bb37 and Bb40, respectively. We conclude that native isolates of B. bassiana represent an important alternative for the control of E. varivestis. However, to demonstrate its effectiveness under field conditions, detailed studies are needed. 相似文献
7.
Rauter AP Filipe MM Prata C Noronha JP Sampayo MA Justino J Bermejo J 《Fitoterapia》2005,76(5):433-438
Diacronema sp. was cultured and its sterols were separated by column chromatography on silica gel. The new sterol 24-ethyl-4alpha-methyl-cholestane-3,20-diol (1) was characterised by NMR and MS spectrometry, as well as (22E)-24-ethyl-4alpha-methyl-5alpha-cholest-22-en-3beta-ol (2) and beta-sitosterol, the major components of the sterol fractions. Neither the biosynthetic origin of the new dihydroxysterol nor its role in the biochemistry of Diacronema is known. 相似文献
8.
Jaime Puértolas Marta Pardos María Dolores Jiménez Ismael Aranda José Alberto Pardos 《Annals of Forest Science》2008,65(6):611-611
9.
Rauter AP Branco I Lopes RG Justino J Silva FV Noronha JP Cabrita EJ Brouard I Bermejo J 《Fitoterapia》2007,78(7-8):474-481
A new lupene triterpenetriol was isolated from the acetone extract of the aerial parts of Salvia sclareoides and characterised as (1beta,3beta)-lup-20(29)-ene-1,3,30-triol (1). In addition, nepetidin (2), nepeticin (3), lupendiol (4), (1beta,11alpha)-dihydroxy-lup-20(29)-en-3-one (5), ursolic acid (6), sumaresinolic acid (7) and hederagenin (8), were identified in this Salvia sp. To the best of our knowledge, the compounds 2 and 7 are new constituents in Salvia spp. The acetone, ethanol, butanol and water extracts of the plant were screened for the in vitro inhibitory activity of acetylcholinesterase (AChE) and butyrilcholinesterase (BChE), enzymes which play a role in the Alzheimer disease. All extracts inhibited acetylcholinesterase activity at 10 microg/ml, a remarkable activity since the standard drug rivastigmine does not inhibit acetylcholinesterase at the same concentration. Regarding the butyrilcholinesterase, the acetone extract at 1000 microg/ml was able to inhibit completely the enzyme activity and the butanol and ethanol extracts, at this concentration, produced a potent inhibition of BchE. 相似文献
10.
Ömür Baysal Francesco Mercati Hatice İkten Raziye Çetinkaya Yıldız Francesco Carimi Yeşim Aysan Jaime A. Teixeira da Silva 《Physiological and Molecular Plant Pathology》2011,75(3):113-119
There is no available data published related to the dissemination of bacterial canker caused by Clavibacter michiganensis subsp. michiganensis (Cmm) and its genetic diversity in Turkey. It is important to control new introduced inoculum sources by commercial seeds and seedlings. Pathogens were identified by morphological features and the identity was confirmed by PCR amplification using a specific primer PSA-4, PSA-R in addition to microbiological tests. ISSR markers showing high polymorphism ratios were selected and used to characterize Cmm strains. The collected strains were classified into different groups on the basis of ISSR-PCR fingerprints, which showed remarkable genetic specificity and diversity not previously identified in Cmm, suggesting that genetic differences are related to dissemination of the pathogen in the region. This is the first ever study carried out on the characterization of Cmm using ISSR. The selected ISSR primers to characterize Cmm can be used to determine genetic differences in further studies. 相似文献