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Open access

V. A. Trach and O. Joharchi

Abstract

One genus (Coleolaelaps Berlese, 1914) and five species (Coleolaelaps agrestis (Berlese, 1887), C. inopinatus Grandi, 1925, H. integer Berlese, 1911, H. krameri (G. et R. Canestrini, 1881) and Gaeolaelaps rhizotrogi (Mašán, 1998)) are recorded for the first time in Ukraine. Morphological characters of female and male of Hypoaspis integer to complement the description are provided.

Open access

Aleksandra Łangowska, Reuven Yosef, Piotr Skórka and Piotr Tryjanowski

Abstract

Bee-eaters (Meropidae) are considered agricultural pests and their presence provokes conflicts with beekeepers and farmers who rely on the pollination services of honey bees. This problem is often deal with through the mass killing of the birds, even though the quantitative evidence on the impact of bee-eaters on honey bee colonies is scarce. The current paper reports the performance of honey bee colonies protected with mist nets from migrating flocks of European bee-eaters Merops apiaster in Israel. In the study the weight gains of bee hives surrounded by mist nets were 6.44 times higher than that of unprotected hives (26.4 kg vs. 4.1 kg). The results confirmed that bee-eaters locally pose a problem to apiaries and potentially to the crops that require pollination. Mist- netting appeared to be an effective mitigation method for alleviating conflicts between beekeepers and bee-eaters. However, the study also showed that bees were able to differentiate between their main predator and other avian species trapped in mist nets and stung only bee-eaters. Moreover, the bees were targeting the most vulnerable body parts of birds which resulted in some bird fatalities. Therefore, due to accidental mortal- ity of birds, mist-netting is recommended only on the migratory routes in cases when bee hives cannot be moved to other areas.

Open access

Rachid Rouag, Nadia Ziane and Slim Benyacoub

Abstract

Habitat preferences were studied in sympatric populations of two Lacertids, Psammodromus algirus and Acanthodactylus erythrurus (Lacertidae) from the National Park of El Kala (north-eastern Algeria). The relationship between habitat physical structure and population densities was studied in order to establish eventual segregation between the two lizards. A difference exists between the two species in their distributions. Acanthodactylus erythrurus is a strictly terrestrial species, usually found on sandy and more open grounds than Psammodromus algirus which can penetrate dense vegetation and look for sunny locations by climbing on shrubs; a behavior which A. erythrurus does not control. Our results confirm spatial segregation on a microhabitat scale, supporting the conclusions that microhabitat selection is an important factor in lizards community organization and contributing to reduce potential competition.

Open access

Ayse E. Borum and Mesut E. Gunes

Abstract

Honey samples obtained by beekeepers taken from thirty-five different apiaries in Turkey’s region of Marmara were investigated for the presence of microorganism. Each honey sample was examined for the number of total aerobic mesofilic bacteria, coliforms, moulds and yeasts and the presence of Salmonella spp., Clostridium botulinum, along with other aerobic bacteriae such as Paenibacillus larvae and Melissococcus plutonius. In total, fifty-four honey samples of different botanical origins including unifloral (Umbelliferae, Leguminosae, Trifolium, Onobrychis), multifloral and chestnut were evaluated in the means of microbiological properties. Microorganisms were isolated in twenty-eight samples (60.86%) of pure cultures and eighteen samples (39.13%) of mixed cultures. On the other hand, no microorganisms were isolated in eight samples. Bacillus spp, Corynebacterium spp., Streptococcus spp., Staphylococcus spp. C. albicans and Penicillium spp. were isolated and identified in other honey samples. The bacteria counts were 4×102 - 1.4×103 cfu/g for aerobic mesofilic bacteria and 1-185 cfu/g for the fungi. The application of sanitary practices (hand washing, avoidance of sneezing or coughing, etc.) may be effective in controlling contamination by microorganisms. On the other hand, air, equipment and dust may be contributing causes of microbiological contamination. Therefore it is important to take precautions in order to avoid such contamination, even though such factors are often difficult to control.

Open access

Ioan Tăuşan, Mădălin Popescu and Alexandru Pintilioaie

Abstract

The Romanian fauna of mantispids (Neuroptera: Mantispidae) is represented by two species, at least. Data on the distribution of both species is relatively scarce. Mantispa styriaca (Poda, 1761) is considered an expansive holomediterranean element. Herein, we report a new record of the species after a half of century. Insights regarding the species ecology are given.

Open access

Piotr Dębowski

Abstract

The sea trout, Salmo trutta L. population in the Vistula River was the largest in the Baltic Sea. Its primary spawning grounds were located in the Carpathian tributaries in the upper river basin. The fish ascended to spawn in two runs: in winter when the fish were immature and spent nearly a whole year in the river, and in summer when mature fish ascended the river and spawned within a few months. This work presents the fisheries and stocking history and scientific studies of this population from the late nineteenth century. The consequences of the most important changes in the sea trout habitat are tracked from construction in the upper river basin in the 1940s and the damming of the river in its middle reaches in Włocławek in 1969. Despite intense stocking that has been conducted for over one hundred years, catches have declined from over 100 tons to nearly zero in recent years. The current state of the population and the possibilities of restoring it are discussed in light of genetic studies.

Open access

Dariusz Ulikowski and Łucjan Chybowski

Abstract

Crayfish catches were conducted using traps in Lake Hańcza, which is the deepest lake in Poland. Two crayfish populations were found to co-exist in the lake: spiny-cheek crayfish (Orconectes limosus Raf.) and signal crayfish (Pacifastacus leniusculus Dana), which is a new species for this lake. Signal crayfish dominated the samples at 98.5% of the specimens caught. The crayfish occurred at depths of 1-10 m. The mean total body length of the male and female signal crayfish (TL) was 99.5 ± 17.8 mm and 96.5 ± 11.7 mm, respectively, while the average body weight (BW) was 38.7 ± 24.9 g and 26.8 ± 9.5, respectively. Chelae were damaged in 4.5% of the individuals. Fishing efficiency (catch per unit effort – CPUE) was 0.96 crayfish trap−1 night−1. Selected characteristics of the population and of individual signal crayfish from Lake Hańcza were compared with those of the two closest neighboring populations of this species in lakes Mauda and Pobłędzie. The confirmed occurrence of the relatively large signal crayfish population in Lake Hańcza excludes this lake as a possible site for native noble crayfish (Astacus astacus L.) restoration.

Open access

Snježana Mirković, Katarina Rajković, Sanja Jeremić, Marijana Gavrilović, Ljiljana Tomić, Valentina Arsić Arsenijević and Boro Krstić

Abstract

The objective of this paper was to assess the antiradical effectiveness of propolis extract (PE) based on 2.2-diphenyl-1-picrylhydrazyl radical (DPPH) bleaching assay kinetic profile. The kinetic profile of scavenging DPPH for PE exhibited one kinetic period characterized by one kinetic constant. The second-order rate constant (k 2) for the oxidation of PE by DPPH, determined for the first time in this study, was 0.17 dm3g−1s−1. The obtained k2 value was compared to that of synthetic antioxidants and natural extracts used in the food industry. Kinetic analysis of PE antiradical effectiveness showed that the k 2 was within the range values for natural colorants of fruit extracts and should be considered as a fast acting natural antioxidant source. The k 2 parameter indicates the extent of oxidation inhibition that is based on all of the kinetic profiles of DPPH bleaching rather than single point measurements. For this reason, the kinetic analysis should become a necessary step for more precise antioxidative characterization of propolis.

Open access

Dominika Andrys, Danuta Kulpa, Monika Grzeszczuk and Bożena Białecka

Abstract

The aim of the study was to determine the influence of jasmonic acid added to culture medium on the growth of plants and antioxidant properties of dry plant material, as well as on the antimicrobial properties of essential oils produced by the narrow-leaved lavender. For plant propagation, MS media supplemented with JA at concentrations of 0.2-1.5 mg dm−3 were used. The use of the lower JA concentrations did not influenced the growth parameters measured, whereas at the higher concentrations (1 and 1.5 mg dm−3) JA caused growth inhibition and a decrease in plant weight. With increasing JA concentration, the number of secretory trichomes decreased. Addition of 0.5 mg dm−3 JA caused an increase in secretory trichome diameter on both the adaxial and abaxial surface of leaves (83.3 and 73.2 μm, respectively). The antioxidant activity of the lavender plants propagated on media with the addition of JA (regardless of the concentration used) was higher than that of the control plants. The plants from JA-supplemented media were used to isolate essential oils, the antimicrobial activity of which was tested using the disc diffusion method at the concentrations of 10 and 50%. All the oils tested exhibited activity towards Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis and Candida albicans. The essential oils isolated from the plants propagated on the medium with 1 mg dm−3 JA were characterized by the highest antimicrobial activity against the majority of the tested microorganisms.

Open access

D. Alimi, A. Abidi, E. Sebai, M. Rekik, R. M. Maizels, M. Dhibi and H. Akkari

Summary

Following our previous findings on the in vitro anthelmintic effect of camel milk on Haemonchus contortus, the current study aimed at investigating its in vivo effect. Investigations were carried out using mice infected with Heligmosomoides polygyrus which is a parasite commonly used to test the efficacy of anthelmintics. Thirty six Swiss white mice of both sexes aged 5 – 6 weeks old, and weighing between 20 and 25 g were orally infected with 0.5 ml dose of 100, 1-week-old H. polygyrus infective larvae (L3). After the pre-patent period, infected animals were randomly divided into 6 groups of 6 animals each. The nematicidal efficacy of camel milk was monitored through faecal egg count reduction (FECR) and total worm count reduction (TWCR). Four doses (8.25; 16.5; 33.0; 66.0 ml/kg body weight (bw)) for fresh camel milk and 22 mg/kg bw for albendazole were studied using a bioassay. Albendazole and 4 % dimethylsulfoxide were included in the protocol as reference drug and placebo, respectively. For all tested doses except 8.25 ml/kg bw, camel milk was effective in vivo against H. polygyrus reducing both faecal egg count and worm count (p < 0.05). The dose 66 ml/kg bw showed the highest nematicidal activity causing a 76.75 % FECR and a 69.62 % TWCR 7 day after initiating the treatment. These results support the possible use of camel milk in the control of gastro-intestinal helminthiasis.