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Maouel D.,Ecole Superieure du Bois | Maynou F.,CSIC - Institute of Marine Sciences | Bedrani S.,Ecole Nationale Superieure dAgronomie
Turkish Journal of Fisheries and Aquatic Sciences | Year: 2014

An integrated fisheries management tool based on a bio-economic model was applied to the small pelagics (sardine) fishery in central Algeria (Mediterranean Sea). The basic bio-economic conditions of the fishery were established and relevant biological and economic indicators were analysed under different management scenarios defined by changes on fleet capacity and daily fishing time. The results show that the fishery is subject to high fishing pressure (1,548 units in 1990 and 4,445 units in 2007) (Maouel 2003, Medrous2013) and current government policies aiming to increase fishing capacity (1,493 new unit sare projected for 2025) (MPRH 2008) would likely worsen the conservation status of the resource, without contributing toa significant volume of catches or economic profits. Instead, a reduction of daily fishing time would allow decreasing the fishing mortality, without significantly reducing the total production or profits of the fishery to the current fleet. However, the short-term loss faced by the industry is a major constraint towards the acceptability of this type of management measures by the fishing sector. © Published by Central Fisheries Research Institute (CFRI) Trabzon, Turkey in cooperation with Japan International Cooperation Agency (JICA), Japan.

Idder-Ighili H.,University of Ouargla | Idder M.A.,University of Ouargla | Doumandji-Mitiche B.,Ecole Nationale Superieure dAgronomie | Chenchouni H.,University of Tebessa
International Journal of Biometeorology | Year: 2015

The date palm scale (DPS) Parlatoria blanchardi is a serious pest due to the damage it inflicts on its host tree (Phoenix dactylifera). To develop an effective control against DPS in arid regions, it is essential to know its bio-ecology including population dynamics and climatic factors influencing the duration and timing of life history and also the densities of different phenological stages (crawlers, first and second instars nymphs, adult males, and adult females). Monitoring of biological cycle and population dynamics of the pest were achieved through weekly counts of DPS densities on leaflets sampled at different position of date palm trees in an oasis of Ouargla region (Algerian Sahara Desert). Within this hyper-arid region, DPS established four generations per year, the most important was the spring generation. Two overlapping generations occurred in spring–early summer and two in autumn–early winter; these two pairs of generations were interspersed by two phases of high-mortality rates, the first corresponds to winter cold and the second refers to the extreme heat of summer. Statistical analysis of the effects of the studied climatic conditions (minimum, maximum and mean temperatures, precipitation, humidity, wind, rain days, and climatic indices) on the DPS densities at different phenological stages showed great variability from one stage to another. Among these, adult females were the most affected by climate factors. For the total DPS population, high values of minimum temperatures negatively affected population density, while high maximum temperatures, hygrometry, and De Martonne aridity index showed a positive influence. © 2015, ISB.

Belkheir B.,Ecole Nationale Superieure dAgronomie | Ghozlane F.,Ecole Nationale Superieure dAgronomie | Benidir M.,Ecole Nationale Superieure dAgronomie | Bousbia A.,8 May 1945 University of Guelma | And 2 more authors.
Livestock Research for Rural Development | Year: 2015

The purpose of this study was to characterize the quality of the mixture milk of dairy cattle farms in the conditions of Algerian production (mountainous area of Kabylia). 134 farms were monitored for twelve months due to one sample per month, were subjected to an investigation that includes the structure, milking practices, hygiene of animals and the characteristics of milk. The analysis of average annual results showed a FR and PR respectively 37,9 ± 5,75 g / l and 33,5 ± 2,6 g / l are above the standards of the Algerian dairy industries and a rate of total bacteria than 5x105 cfu / ml. 21,6% of the farms had a freezing point higher than -0,52 ° C. The lactose content of which is 43,15 ± 2,96 g / l and still low compared to standards. The CMT test performed on 150 dairy cows in 22 farms was found to be positive in 47% of cows. The milk yield was estimated to 4 805 ± 1489 kg / DC / year and 14,36 ± 4,6 kg of technical average / DC / D for an average dairy milk of 38 477 ± 27 537 Kg per farm. The latter is largely dependent on the concentrate. PCA was performed to construct a typology of milk. This identified three classes of milk : Classes 1 and 2 are relatively good physicochemical and hygienic quality milk with average closer to the average of the total sample; in contrast, Class 3 is characterized by milks of insufficient quality. © 2015, Fundacion CIPAV. All rights reserved.

Calliptamus barbarus (Orthoptera: Acrididae) is the most polymorphic species within the genus Calliptamus. It shows a morphological polymorphism (three hind femoral spots, or only one hind femoral spot). Several studies have been made in order to distinguish the two forms: morphometry, number of ovarioles, sound production, protein and enzyme system. The aim of our work is to assess whether the two forms can be considered as different taxa and to perform a molecular phylogenetic study of two populations of C. barbarus collected from two different Algerian localities. No clear genetic differentiation was found between the samples with different morphologies. Additionally, the samples from Algeria do not form a monophyletic sister clade compared to the one formed by the sequences from GenBank from other geographical regions. Despite the morphological differences shown between the two populations, our molecular study indicates that there are no differences at a molecular level using the two mitochondrial genes COI and 16S. © 2016 Société entomologique de France.

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