Landscape features determine brown trout population structure and recruitment dynamics     

Douglas A. Jones  Abbas Akbaripasand  Shinichi Nakagawa  Gerard P. Closs 《Ecology of Freshwater Fish》2019,28(4):554-562

Variation in brown trout (Salmo trutta L.) population recruitment and structure is related to migratory patterns, which should depend on ease of access to habitats providing increased opportunity for growth. We quantified the number of young of year (YOY) as a proportion of the total number of brown trout at 24 locations on 11 streams within the Taieri catchment, New Zealand, including back calculated growth rates and emergence dates from otoliths. Locations with high absolute and relative abundance of YOY fish were related to elevation and distance from the river mainstem (habitat used by migratory fish), fish density, and the interaction between invertebrate food biomass, distance and elevation. Hatch date and growth were not related to the proportion of YOY fish, though growth was negatively correlated to total fish density. We suggest landscape features play a large role in determining recruitment and population structure. Locations at lower elevations have a high YOY density, high competition and lower growth, likely prompting out‐migration. These conditions could be created by successful return migration and spawning of large fecund fish resulting in YOY densities exceeding the habitat carrying capacity. Environmental factors, such as food availability, also played a role in determining population structure. These results provide an example of how population structure and recruitment might be controlled by local conditions and access to high growth environments in wild populations of introduced brown trout across a catchment.  相似文献   

Aggregation pheromone traps, a major component of IPM strategy for the red palm weevil, Rhynchophorus ferrugineus in date palms (Coleoptera: Curculionidae)     

M. S. T. Abbas  S. B. Hanounik  A. S. Shahdad  S. A. AI-Bagham 《Journal of pest science》2006,79(2):69-73

The population fluctuation of the red palm weevil, Rhynchophorus ferrugineus was studied, using the aggregation pheromone traps, during 2000 and 2001 in the United Arab Emirates. The insect population increased gradually from January to reach its peak in March, April, or May. The populations in three date palm plantations were much less in 2001 compared to 2000 with reductions of 29.7–51.7%. An evaluation of the performance of the pheromone traps showed that they could capture 4.4 to 20.7% of the resident populations of R. ferrugineus in the three different date palm plantations. No significant differences could be found in rates of capture between males and females. Individuals of marked weevils released in date palm plantations migrated 1–7 km from the plantations in which they were released. The released marked weevils were recaptured, mostly, within 3–5 days post release.  相似文献   

Studies on kinetics and thermostability of a novel acid invertase from Fusarium solani     

Bhatti HN  Asgher M  Abbas A  Nawaz R  Sheikh MA 《Journal of agricultural and food chemistry》2006,54(13):4617-4623

The present investigation deals with purification and thermal characterization of an acid invertase produced by Fusarium solani in submerged culture. The maximum enzyme activity (9.90 U mL(-1)) was achieved after 96 h of cultivation at pH 5.0 and 30 degrees C in a basal medium containing molasses (2%) as the carbon and energy source supplemented with 1% peptone. Invertase was purified by ammonium sulfate fractionation and column chromatography on DEAE-cellulose and Sephadex G-200. The purified enzyme was proven to be homogeneous by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The molecular mass of the enzyme was 65 kDa. The optimum pH and temperature for activity were 2.6 and 50 degrees C, respectively. The Km value for sucrose was 3.57 mM with an activation energy of 4.056 kJ mol(-1). Enthalpies of activation (DeltaH) were decreased while entropies (DeltaS) of activation increased at higher temperatures. The effects of alpha-chymotrypsin and 4 M urea were tetraphasic with periodic gain and loss of enzyme activity. A possible explanation for the thermal inactivation of invertase at higher temperatures is also discussed.  相似文献   

In vitro and in vivo acaricidal activity of a herbal extract     

Zaman MA  Iqbal Z  Abbas RZ  Khan MN  Muhammad G  Younus M  Ahmed S 《Veterinary parasitology》2012,186(3-4):431-436

The anti-tick efficacy of combined aqueous herbal extracts of Azadirachta indica leaves, Nicotiana tabacum leaves, Calotropis procera flowers and Trachyspermum ammi seeds was evaluated using adult immersion test, larval packet test and ear bag method. The extract exhibited lethal effects on egg laying (index of egg laying=0.371404±0.00435), hatching (22.35%) and total larval mortality at 50 mg ml(-1) and reduced tick intensity on the infested calves (18 detached out of 35 at 45% (w/w) suspension, topically applied). The herbal extract exerted dose- and time-dependent response against all the developmental stages of Rhipicephalus (Boophilus) microplus considered in this study, thus justified their use in the traditional system of Pakistan.  相似文献   

中国地衣新记录属——安子纳属     

王玉良  阿地里江·阿不都拉  阿不都拉·阿巴斯 《干旱区研究》2012,29(1):179-181

通过对大别山安徽段山区所采集地衣标本的整理,利用光学生物显微镜、电子显微镜,观察其解剖结构扫描,并采用薄层层析等方法进行详细的分类学鉴定,发现一个新记录属安子纳属(Anzina Scheid.）和一个新纪录种[WTBX]〔Anzina carneonivea (Anzi.) Scheid.〕。对其分布范围、化学成分、解剖结构和鉴别特征进行了简要概括。
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Biological control of weeds: research by the United States Department of Agriculture-Agricultural Research Service: selected case studies     

Quimby PC  DeLoach CJ  Wineriter SA  Goolsby JA  Sobhian R  Boyette CD  Abbas HK 《Pest management science》2003,59(6-7):671-680

Research by the USDA-Agricultural Research Service (ARS) on biological control of weeds has been practiced for many years because of its inherent ecological and economic advantages. Today, it is further driven by ARS adherence to Presidential Executive Order 13112 (3 February 1999) on invasive species and to USDA-ARS policy toward developing technology in support of sustainable agriculture with reduced dependence on non-renewable petrochemical resources. This paper reports examples or case studies selected to demonstrate the traditional or classical approach for biological control programs using Old World arthropods against Tamarix spp, Melaleuca quinquenervia (Cav) ST Blake and Galium spurium L/G aparine L, and the augmentative approach with a native plant pathogen against Pueraria lobata Ohwi = P montana. The examples illustrated various conflicts of interest with endangered species and ecological complexities of arthropods with associated microbes such as nematodes.  相似文献   

First report of false smut disease caused by Graphiola phoenicis on date palm trees in Qatar     

E. H. Abbas  A. S. Abdulla 《Plant pathology》2004,53(6):815-815

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Copper status in breeding and racing camels (<Emphasis Type="Italic">Camelus dromedarius</Emphasis>) and response to cupric oxide needle capsules     

Abu Damir H  Abbas TA  Alhaj Ali M 《Tropical animal health and production》2008,40(8):643-648

Copper was determined in the blood of breeding camels, camel calves and racing camels to evaluate copper status in these animals in UAE. Low blood copper concentrations were reported in newly born camel calves (100%) and calves 2–4 months old (68%), breeding camels at early (55.6%) and at mid lactation (48%) and at late pregnancy (69%). This is attributed to the low copper and high sulfate in the Rhodes grass which is the only diet offered to the breeding camels. On the other hand only 9.7% of racing camels showed low copper levels. This is because copper is routinely offered to racing camels when their blood copper is low. Cupric oxide needle capsules orally administered at the rate of 8 g per adult camel was effective in elevating blood copper from 7.083 μmol/L at day zero to 10.074 μmol/L at day 28 after dosing.  相似文献   

地衣对重金属的累积效应用于乌鲁木齐市大气监测的研究     

努斯热提古丽·安外尔  古再丽努尔·阿卜来提  买买提·沙塔尔  阿不都拉·阿巴斯  艾尼瓦尔·吐米尔 《新疆农业科学》2012,49(12):2310-2318

[目的]评价地衣重金属富集能力及其在城市空气环境质量评价中的应用前景.[方法]利用地衣移植法把丽石黄衣移植到乌鲁木齐市区15个监测点,用原子吸收光谱仪测量地衣体内6种重金属含量,根据重金属含量计算单项污染量指数和Nemerow综合污染指数.[结果]随着移植时间的延长地衣体内的重金属含量出现上升趋势,丽石黄衣体内重金属含量具有显著的时空变化特征.同时把单向污染量指数作为变量进行聚类分析和主成分分析,显示15个监测点分为轻污染区、中度污染区、重污染区,严重污染区等三个等级.[结论]地衣具有较高的重金属富集能力,对大气污染较敏感,可以作为大气环境质量评价指示地衣种类.  相似文献   

Testicular torsions in veterinary medicine     

Raisi  Abbas  Davoodi  Farshid 《Veterinary research communications》2022,46(2):303-313

The purpose of this review is to provide a comprehensive comparison of spermatic cord torsion in domestic animals. Spermatic cord torsion leads to occlusion of testicular blood flow resulting in ischemia and tissue hypoxia. Spermatic cord torsion has been reported in all domestic mammals but dogs and horses are overrepresented. Abdominal pain (colic), anorexia, vomiting, lameness, and stiff gait are the most common clinical signs reported. The condition may be asymptomatic in cases of a low degree of spermatic cord torsion. In dogs, spermatic cord torsion is most commonly reported in undescended testes, which in some cases are neoplastic. However, in horses, spermatic cord torsion occurs more commonly in scrotal testes. Surgical treatment for spermatic cord torsion depends upon the degree and duration of torsion. If the affected testis is located within the scrotum and determined to still be viable, detorsion with orchidopexy can be performed. Orchiopexy of the unaffected scrotal testis is also recommended in stallions. If the affected testis cannot be salvaged, unilateral or bilateral orchidectomy is recommended. In all cases of spermatic cord torsion of an undescended testis, orchidectomy is recommended. Veterinarians should be aware of the clinical signs and treatment options for spermatic cord torsion in domestic mammals.

Graphical abstract

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