International Journal of Zoology
[SJR: 0.389] [H-I: 8] [2 followers] Follow
Open Access journal
ISSN (Print) 1687-8477 - ISSN (Online) 1687-8485
Published by Hindawi [334 journals]
- Corrigendum to “Phenotypic Variation in Freshwater Murrel, Channa
punctatus (Bloch, 1793) from Northern and Eastern Regions of India Using
PubDate: Tue, 14 Mar 2017 00:00:00 +000
- Cytochrome c Oxidase Sequences of Zambian Wildlife Helps to Identify
Species of Origin of Meat
Abstract: Accurate species identification is a crucial tool in wildlife conservation. Enforcement of antipoaching law is more achievable with robust molecular identification of poached meat. Determining the region where the animal may have been taken from would also be a useful tool in suppression of cross-border trade of poached meat. We present data from a cytochrome c oxidase “barcoding” study of Zambian ruminants that adequately identifies the species of origin of meat samples. Furthermore, the method demonstrates possible improvement and application in regional variation in sequence identity that has a potential for discriminating meat samples from different subpopulations.
PubDate: Tue, 22 Nov 2016 14:18:07 +000
- A Revision of the Selenocosmiine Tarantula Genus Phlogiellus Pocock 1897
(Araneae: Theraphosidae), with Description of 4 New Species
Abstract: The tarantula genus Phlogiellus (Pocock 1897) is revised. The genus is diagnosed against all other selenocosmiine genera for the first time along with a new generic description. The tribe Yamiini (Kishida 1920) is diagnosed against all other selenocosmiine tribes. All Phlogiellus species are diagnosed from all congeners; all species are mapped. Complete dichotomous keys for both sexes of all species are included. Where appropriate, intraspecific variation is discussed. Four new species are described: P. bogadeki sp. nov. from Hong Kong, P. johnreylazoi sp. nov. from Palawan Island, Philippines, P. moniqueverdezae sp. nov. from Ranong, Thailand, and P. pelidnus sp. nov. from Sabah, Borneo. The type species P. atriceps (Pocock 1897) holotype male is redescribed and the male P. baeri (Simon 1877) is described in detail for the first time. The validity of P. inermis (Ausserer 1871) is confirmed. Relationships between all known selenocosmiine genera and Phlogiellus from the Philippines are discussed and several character traits are newly diagnosed. The tribe Phlogiellini (West et al. 2012) is a junior synonym of Yamiini (Kishida 1920). Selenocosmia orophila (Thorell 1897) from Myanmar, Selenocosmia insulana (Hirst 1909) from Djampea (= Jampea) Island, and Selenocosmia obscura (Hirst 1909) from Sarawak, Borneo, are transferred to Phlogiellus, altering the specific names to Phlogiellus orophilus (Thorell 1897) comb. nov., Phlogiellus insulanus (Hirst 1909) comb. nov., and Phlogiellus obscurus (Hirst 1909) comb. nov. Phlogiellus subarmatus (Thorell 1891) is transferred to Chilobrachys (Karsch 1891), becoming Chilobrachys subarmatus (Thorell 1891) comb. nov. Phlogiellus kwebaburdeos (Barrion-Dupo et al., 2014) is transferred to Orphnaecus (Simon 1892), becoming Orphnaecus kwebaburdeos (Barrion-Dupo et al., 2014) comb. nov. Phlogiellus ornatus (Thorell 1897) and Phlogiellus nebulosus (Rainbow 1899) are considered species inquirenda. Phlogiellus baeri (Simon 1877) is no longer considered incertae sedis; Phlogiellus bicolor (Strand 1911) and Phlogiellus insularis (Simon 1877) are considered incertae sedis.
PubDate: Tue, 27 Sep 2016 11:16:11 +000
- Phenozan Influence on the Physiological-Biochemical Parameters of the
Young Minks Leading to Their Advanced Properties
Abstract: The antioxidant influence on the physiological-biochemical parameters of productive animals is one of the most important directions in modern animal science. Phenozan is a synthetic antioxidant with high biological activities including those for animals. The positive effects of phenozan on the physiological-biochemical parameters of the mink blood were found. These effects are leading to the intensive growth, strong health, enhancement of the mink fur quality, and so forth. The total amount of the erythrocytes in the mink blood increased by about 4-5% due to phenozan inclusion in the mink diet. Even a more significant increase was found in hemoglobin content in the mink blood and erythrocytes (by about 9.5% and 8.8%, resp.) due to phenozan inclusion of 100 mg/day, whereas it was found only by about 6.1–5.3% or 5.5–0.3%, owing to phenozan inclusion of 50 or 150 mg/day. For many other parameters the optimal phenozan concentration was about 100 mg/day per head according to the result obtained for all studied animal groups. Thus, phenozan can be successfully used as a biologically active compound for mink nutrition and is recommended for other farm animals.
PubDate: Sun, 18 Sep 2016 14:24:41 +000
- Antipredator Behaviour of Limnonectes blythii (Boulenger, 1920) (Anura:
Dicroglossidae) from Kedah, Peninsular Malaysia
Abstract: The frog Limnonectes blythii was collected at different locations in Kedah, Peninsular Malaysia, three from Sungai Sedim Recreational Forest, two from Bukit Hijau Recreational Forest, and two from Ulu Paip Recreational Forest. Nine antipredator mechanisms were displayed by this species, including fleeing, hiding among leaf litter, diving into water, bladder discharge, defensive call, feigning death, crouching, inflating the body, and body-raising. The two latter actions were accompanied by a defensive call. These observations document for the first time antipredator behaviour in L. blythii.
PubDate: Sun, 31 Jul 2016 06:54:26 +000
- Some Important Observations on the Populations of Hooded Vultures
Necrosyrtes monachus in Urban Ghana
Abstract: Despite major declines in the population of vultures around the world, noticeable increases were reported in the populations of Hooded Vultures Necrosyrtes monachus over the past decade in Accra—an important vulture habitat in Ghana. In recent times, however, there is a growing concern that the vulture numbers are decreasing even though scientific data to support this is nonexisting. As a vital zoogeographical and conservation tool, it is important to keep an up-to-date knowledge about urban bird populations amidst rapid urbanization and associated changes. Using a combination of field data, literature review, and stakeholder consultations, it was indicative that severe decline might have indeed occurred in the populations of Hooded Vultures in Accra. Evidence suggests the killing of vultures for consumption, traditional medicine, and black magic in an undercover trade with possible transboundary connections as important underlying factor. Additional factors suspected to underlie the declines include changes in management of urban facilities and destruction of roosting and nesting trees. The implications of interspecific competition with Pied Crows Corvus albus on Hooded Vultures however remain unclear. There is an urgent need for conservation campaign and education to save the Hooded Vulture in Ghana.
PubDate: Wed, 29 Jun 2016 09:56:29 +000
- Comparative Study of Integrated Pest Management and Farmers Practices on
Sustainable Environment in the Rice Ecosystem
Abstract: Integrated pest management (IPM) is an environmentally friendly technology. IPM is a multifaceted approach to pest management that seeks to minimize negative impacts on the environment. This technique is an important step towards providing healthy, viable food for a growing global population. The focus of this study was to examine the impact of integrated pest management in a rice agroecosystem. Currently, more than 80% of farmers rely on pesticides. IPM methods employed in our study had an impact on the number of healthy tillers and hills and grain weight. The lowest percentage of dead heart (1.03) and white head (2.00) was found in the IPM treated plots. These plots had an average yield of 7.4 tonne/ha. We found that there were significant differences between the treatment and the observed percentage of dead heart, grain weight, and yield. We conclude that IPM practices are an effective strategy for obtaining high rice yields while protecting the environment and creating a more sustainable agroecosystem. Furthermore, the need for ongoing research and training on IPM methods will be essential for creating a sustainable rice agroecosystem.
PubDate: Thu, 07 Apr 2016 13:35:31 +000
- Species Composition of Tropical Understory Birds in Threatened East
African Coastal Forests Based on Capture Data
Abstract: The East African coastal forests are subject of haphazard modification following anthropogenic pressures including tree cutting and clearing for agriculture. These activities, which are leading cause of habitat disturbance and species loss, are the major challenge in the management of sensitive wildlife species such as forest understory birds. This study investigated species composition of understory birds in the coastal forests of northeastern Tanzania to generate information for the management of the landscape and biodiversity in the area. Using mist nets, birds were trapped from core and edge habitats of representative forest patches. Trapped birds were classified to species level and categorized into bird guilds based on their levels of forest dependence. It was found out that species richness was influenced by forest patch size rather than level of habitat disturbance. Edge habitat was also found to be important in hosting higher number of forest understory birds, especially generalists—but this should be treated with caution because following habitat destruction that is ongoing in the study area, there is a danger of generalist wiping out specialist species due to competitive exclusion. Strict control measures to stop illegal tree cutting and agricultural activities near the forests were recommended for sustainable conservation of the understory birds in the forests.
PubDate: Sun, 03 Apr 2016 08:53:55 +000
- Feeding Ecology of Taruca (Hippocamelus antisensis) Populations during the
Rainy and Dry Seasons in Central Peru
Abstract: Tarucas (Hippocamelus antisensis) live in rocky areas in the Andes, from northern Peru to northern Argentina. Microhistological analyses on their feeding ecology during the rainy and dry seasons were done at a National Park and a Landscape Reserve. The diet was diverse and more than 50 species were identified from the feces. Grass species were most often detected as eaten by taruca during the rainy season comprising near 70% of the consumed fragments with 35 plant species identified as eaten then. In the dry season, around 50 species were identified as eaten by tarucas, mostly dicotyledonous. The main species consumed in both seasons were Werneria nubigena, Poa gymnantha, Senecio comosus, and Ephedra americana. The ecological density was an intermediate value compared to other observed values in Peru. This is the first study to find the importance of grasses for tarucas, selected when soft, during the rainy season. A possible overlap with domestic ungulates’ diets should be explored, helping the conservation of taruca and generating an adequate management of the species and the ecosystem. There is a change in the palatable offer of food items during the rainy season, when most of the Gramineae species are tender.
PubDate: Mon, 15 Feb 2016 13:25:31 +000
- Phenotypic Variation in Freshwater Murrel, Channa punctatus (Bloch, 1793)
from Northern and Eastern Regions of India Using Truss Analysis
Abstract: Morphometric variation study was carried out using truss analysis in freshwater murrel, Channa punctatus (Bloch, 1793), to explore different phenotypic stocks of C. punctatus. Significant variation in the morphometric analysis was observed using the truss network and multivariate analysis of the three subpopulations of freshwater murrel, C. punctatus, from the two different regions of India. Principal component analysis accounted for a total variation of 91.95% by the first three principal components. PC 1 represented the variation due to size and PC 2 and PC 3 represented variations due to shape. The 95% confidence ellipses depicted the clear isolation between the samples in scatter graph of PC 1 on PC 2. The combined groups plot (DF 1 on DF 2) based on discriminant function analysis (DFA) also validated the existence of three different subpopulations. In group classification using DFA, 100 percent of all the samples were correctly classified into their original subpopulation. These results support the existence of multiracial composition of C. punctatus across the different geographical isolated sites and, thus, these findings indicate the presence of three different phenotypic stocks of C. punctatus.
PubDate: Mon, 15 Feb 2016 06:36:20 +000
- Descriptive Osteology of a Newly Described Stone Loach, Oxynoemacheilus
chomanicus (Kamangar et al., 2014) (Cypriniformes, Nemacheilidae)
Abstract: Oxynoemacheilus chomanicus is a newly described species of the family Nemacheilidae from the Choman River drainage of the Tigris basin. This study was conducted to provide the detailed osteological characteristics of this species and comparing them with those of other endemic species of the genus Oxynoemacheilus from inland water basins of Iran, namely, kiabii, O. persa, O. brandtii, O. kermanshahensis, and O. bergianus. For this purpose, nine specimens of O. chomanicus were collected, cleaned, and stained for osteological examination. Then, a detailed description of their skeletal structure was provided. The results showed that O. chomanicus can be distinguished from other studied species of the genus Oxynoemacheilus due to possessing an orbital shelf, number of the vertebrae, number of the hypurals, number of the unbranched rays in anal fin, features of the hemal and neural spines, and connection pattern of the parietal and frontal.
PubDate: Thu, 28 Jan 2016 10:38:59 +000
- Diversity and Dynamics of Sand Flies (Diptera: Psychodidae) of Two
Cutaneous Leishmaniasis Foci in the Fes-Boulemane Region of Northern
Abstract: Cutaneous leishmaniasis (CL) is an infectious disease caused by various species of Leishmania and transmitted by several species of sand flies (Diptera: Psychodidae). In order to evaluate the risk of leishmaniasis transmission in Fes-Boulemane, an investigation was carried out in two localities, Aichoun and Bouasseme, during 2011. From January to December, 1120 specimens were collected in Aichoun comprising six species belonging to two genera: Phlebotomus sergenti (76.07%), Phlebotomus longicuspis (9.01%), Phlebotomus perniciosus (8.48%), Phlebotomus papatasi (4.82%), Sergentomyia minuta, and Sergentomyia fallax. For Bouasseme, seven species were identified with Phlebotomus sergenti (60.39%) dominating, followed by Phlebotomus perniciosus (20%) and Phlebotomus longicuspis (12.15%). The remaining species, Phlebotomus papatasi, Phlebotomus ariasi, Sergentomyia minuta, and Sergentomyia fallax, were less prevalent. The activity of sand flies in both localities is marked by the dominance of Ph. sergenti with two peaks occurring in June and September. In order to obtain a better understanding of sand fly diversity among their species, results were analyzed by the ecological indices determinant: specific richness, the relative abundance, and Shannon-Weiner index (H′). Further studies of sand fly diversity should employ statistical tests and molecular analyses. This study can be useful in the implementation of appropriate future control measures.
PubDate: Thu, 24 Dec 2015 08:35:09 +000
- The Male Reproductive Cycle of the Spotted Toad-Headed Agama,
Phrynocephalus maculatus, in Iran
Abstract: The spotted toad-headed agama, Phrynocephalus maculatus, distributed in the central and southeastern arid regions of Iran, belongs to the Agamidae family. In this research, the male reproductive cycle of this species was studied from 5 April to 5 August, 2013. Totally, 40 adult males were collected at midday from southern deserts of Damghan County, located in Semnan Province of Iran. Testes were removed and processed for morphometric and histological studies. The spermatogenic cycle begins from early April, mating occurs in mid-May, and it ends in August. Maximum reproductive activity occurs in early June and reduces from early July and ends in August. The numbers of seminal vesicles were 33–127 and their diameter varied between 69.0 and 258.3 microns. The diameter of tunica albuginea varied between 3.0 and 8.1 microns. The diameter of germinal layer varied between 10.0 and 110.0 microns. There were significant differences in macroscopic and microscopic testicular characters between months. Also, there were no significant differences in the testicular and hemipenal characters between the left side and the right side of body. Since spermatogenesis occurs from April through August, P. maculatus follows an associated reproductive cycle typical for temperate species.
PubDate: Mon, 23 Nov 2015 11:08:20 +000
- Seeing Is Feeding for the Frugivorous Bird Brown-Eared Bulbul (Microscelis
Abstract: We examined feeding behavior by visually blocking fruit to establish a new theory of bird damage management for agricultural practices. Partly or fully invisible clusters of grapes were fixed on a perch. The birds selectively pecked the clearly visible part of the half-visible bag at a pecking count rate of 0.94–1.00 (95% CI). Half-visible bags allowed the birds to look inside like a skirt and detect the initially hidden portions of grapes, which were covered with opaque white bags. However, very few birds pecked at the white bags that were partially covering the grapes. That is, very few birds attempted to eat covered but easily detectable fruits. Only five birds gravitated toward the grapes in the completely covered nontranslucent bags, but they never pecked at them. Our results show that visual blocking could be a promising new technique to prevent bird damage.
PubDate: Tue, 03 Nov 2015 11:07:15 +000
- Exploiting Scanning Behavior for Predators Can Reduce Rice Damage Caused
Abstract: Rice is often damaged by birds, especially sparrows, in Asia. Bird nets are sometimes used as countermeasures; however this approach is expensive and labor intensive. For this reason, farmers generally eschew bird nets, even though no alternative countermeasures are available. This study focused on exploiting the bird behavior of scanning for predators to reduce crop damage. When birds forage for seeds on the ground they often stop pecking and briefly raise their heads, apparently to scan for predators. Low visibility habitats increase scanning behavior and increased scanning behavior reduces habitat quality from the bird’s perspective; therefore, this study tested the relationship between rice damage rate and visibility at the periphery of rice fields, where tree sparrows rest after feeding. Overall, low visibility reduced damage to rice. Because visibility was mainly affected by weeds, weed management techniques contribute to crop damage management. To reduce damage, weeding can be decreased; therefore, this technique is cost- and labor-efficient.
PubDate: Mon, 07 Sep 2015 10:58:59 +000
- Ecological Niche Modeling of Seventeen Sandflies Species (Diptera,
Psychodidae, Phlebotominae) from Venezuela
Abstract: The purpose of this study is to create distribution models of seventeen Lutzomyia species in Venezuela. Presence records were obtained from field collections over 30 years by several research teams. We used maximum entropy method for model construction based on 30 arc-second resolution environmental layers: 19 bioclimatic variables, elevation, and land cover. Three species were distributed throughout north-central Venezuelan, two restricted to northern Venezuelan coast, and three throughout the west; five were restricted mainly to the Andean and finally two species within sparse pattern. The most important variables that contributed were related to precipitation. The environmental niche model of sandflies might be a useful tool to contribute to the understanding of the ecoepidemiological complexity of the transmission dynamics of the leishmaniases.
PubDate: Sun, 08 Feb 2015 10:17:15 +000
- Larval Development of the European Lobster and How Small Heterochronic
Shifts Lead to a More Pronounced Metamorphosis
Abstract: We redescribe the larval stages of the European lobster, Homarus gammarus, based on autofluorescence composite imaging. We focus on larval stages (II) to (IV). Compared to the American lobster, Homarus americanus, differences are most apparent in stage (III). This stage appears more mature in H. gammarus; for example, the rostrum is already curved and bears spines, and the appendages are better developed and longer and more differentiated. In H. americanus stage (III) shows a stronger resemblance to stage (II). As a result of the morphology of stage (III), the “metamorphic” moult between stage (III) and stage (IV) in H. gammarus is less drastic than in H. americanus. Metamorphosis is characterised by two criteria. It involves (1) a drastic change in morphology in (2) a short amount of time. It has hence been suggested that a more pronounced metamorphosis evolves by two factors affecting these criteria, namely, (1) the evolution of specialised larval features, which increase the morphological disparity between larva and adult that makes the change of morphology more drastic, and (2) the skipping of entire stages. This means larval forms ancestrally moult over several intermediate forms into the definite adult morphology. Yet, in more derived forms the stages with intermediate morphologies are no longer expressed; highly specialized larvae moult into the adult within a single moult (in the most extreme case) hence bridging the morphologies of larvae and adult in a shorter amount of time. The example of the two Homarus species demonstrates that this explanation is not the only possible one. Additionally, differences of a single larval stage (in this case larval stage (III)) can lead to a more or less metamorphic-appearing ontogenetic sequence.
PubDate: Mon, 12 Jan 2015 14:26:48 +000
- Efficacy of 2-Phenoxyethanol as an Anaesthetic for Adult Redline Torpedo
Fish, Sahyadria denisonii (Day 1865)
Abstract: Efficacy of 2-phenoxyethanol for redline torpedo fish exposed to five concentrations (200, 300, 400, 500, and 600 μlL−1) was evaluated. The time periods necessary for each characteristic stage of induction and recovery were recorded. Results indicated that the induction time of the fish exposed to five anaesthetic concentrations significantly decreased with increasing concentration but recovery time was independent of concentration. Concentration of 500 μlL−1 (induction time: 173 ± 7 and recovery time: 129 ± 41 seconds) was determined as the minimum effective concentration that induces anaesthesia in less than 3 minutes.
PubDate: Mon, 08 Dec 2014 13:19:45 +000
- Spermatogenic Waves and Expression of AR and ERs in Germ Cells of Podarcis
Abstract: Androgens are considered the main hormones that regulate spermatogenesis, but a lot of evidence confers to estrogen a key role in this process. In the testis of the seasonal breeder lizard Podarcis sicula we analyzed by means of in situ hybridization the expression of the androgen receptor (AR) and of the two types, α and β, of the estrogen receptors (ERs) throughout the three periods of the annual cycle: mating (spring-early summer), postmating-refractory (late summer), and autumnal recrudescence. The results show that during the mating period AR and ERs are expressed in all germ cells present in the tubules from spermatogonia to spermatozoa. During the postmating-refractory period, when only spermatogonia are present in the tubules, almost all express ERs and very few AR mRNA. During the autumnal recrudescence the localization of AR and ERs is the same of the mating period except for the population of the primary spermatocytes. The expression of the investigated receptors is peculiar in these cells that are positive in the middle-late pachytene stage of the meiotic prophase and negative in preleptotene. A possible functional role of the observed differences during spermatogenesis and in the spermatozoa is also discussed.
PubDate: Sun, 23 Nov 2014 00:00:00 +000
- Behavioural Descriptions of Indian Pangolins (Manis crassicaudata) in
Abstract: Conservation breeding programmes as an essential tool for conservation of endangered species require a sound knowledge on behaviour of the species. At present time, knowledge of behaviour and biology of Indian pangolins is inadequate and inconsistent. During the present study, an ethogram was developed based on the behavioural observations of seven Indian pangolins (Manis crassicaudata) at Pangolin Conservation Breeding Centre, Nandankanan Zoological Park, Odisha, India, between February 2012 and January 2013. A total of 27 behaviours of seven distinct behavioural categories (stationary body positions, locomotory patterns, maintenance behaviours, explorative behaviours, defensive behaviours, reproductive/social behaviours, and others) were described and illustrated. The results offer a consistent frame of reference for further studies on behavioural patterns of Indian pangolins. Besides, these preliminary observations could be useful in management and breeding of the species in captivity.
PubDate: Wed, 19 Nov 2014 07:10:02 +000
- The Female Reproductive Cycle of the Bedriaga Plate-Tailed Gecko,
Teratoscincus bedriagai (Sauria: Gekkonidae) in Iran
Abstract: The Bedriaga Plate-tailed Gecko, Teratoscincus bedriagai Nikolsky, 1900, is distributed in the northern and eastern desert basins of the Central Plateau of Iran, Sistan, and the desert regions of southern Afghanistan. Iranian specimens are believed to be rare in collections. In this study, the reproductive cycle of this species has been investigated through focusing on oogenesis from 5 April to 5 August, 2013. Generally, 15 adult females were collected by hand at midnight from southern parts of Damghan County, situated in Semnan Province of Iran. Ovaries were removed and processed for the purpose of histological and morphometric studies. The results revealed that oocyte growth starts in early April and terminates in late July. Moreover, mating commences in spring, especially at the beginning of May, with oviposition occurring from late May to late July. Approximately, 1 to 2 eggs are laid by females per clutch with the possibility of producing a secondary clutch later in the season. The maximum reproductive activity takes place in May and continues with a decreasing trend in June and more reduction in July and finally ends in August. No significant difference was observed between right and left side of reproductive system. Therefore, oogenesis occurs from April to July, while T. bedriagai follows an oogenic cycle typical for temperate species.
PubDate: Sun, 16 Nov 2014 00:00:00 +000
- Environmental Determinants Influencing Seasonal Variations of Bird
Diversity and Abundance in Wetlands, Northern Region (Ghana)
Abstract: The study assessed major environmental determinants influencing bird community in six wetlands over a 2-year period. A combination of visual and bird sounding techniques was used to determine the seasonal variations in bird abundance, while ordination techniques were performed to determine the influence of environmental factors on bird assemblage. A total of 1,169 birds from 25 species and 885 individuals from 23 species were identified in the wet and dry season, respectively. The shallow close marshes supported the greatest number of birds () compared to the riparian wetlands. Bird diversity was significantly higher in the wet season than in the dry season (). Cattle egret (Bubulcus ibis) and marsh warbler (Acrocephalus palustris) were the most abundant. Using the IUCN “Red List” database guide, we noted that 96.2% of birds identified were least concern (LC). The yellow weaver bird (Ploceous megarhrynchus) was the only vulnerable species (VU) and represented 3.8%. From the three variables tested, bushfire and farming practices were the major threats and cumulatively explained 15.93% (wet season) and 14.06% (dry season) variations in bird diversity and abundance. These findings will help wetland managers design conservation measures to check current threats on birds from becoming vulnerable in the future.
PubDate: Wed, 29 Oct 2014 12:38:53 +000
- Erratum to “Foraging Habitat Distributions Affect Territory Size and
Shape in the Tuamotu Kingfisher”
PubDate: Wed, 29 Oct 2014 06:15:08 +000
- Effects of Quinizarin and Five Synthesized Derivatives on Fifth Larval
Instar Midgut Ecdysone 20-Monooxygenase Activity of the Tobacco Hornworm
Abstract: The plant allelochemical, quinizarin (1,4-dihydroxy-9,10-anthraquinone), and five anthraquinones that were synthesized from quinizarin, namely, 1,4-anthraquinone; 2-hydroxy-1,4-anthraquinone; 2-methoxy-1,4-anthraquinone; 9-hydroxy-1,4-anthraquinone; and 9-methoxy-1,4-anthraquinone, were assessed as to their effects on the essential, P450-dependent ecdysone 20-monooxygenase system of the insect model Manduca sexta (tobacco hornworm). This steroid hydroxylase converts the arthropod molting hormone, ecdysone, to the physiologically required 20-hydroxyecdysone form. M. sexta fifth larval instar midgut homogenates were incubated with increasing concentrations (10−8 to 10−3 M) of each of the six anthraquinones followed by ecdysone 20-monooxygenase assessments using a radioenzymological assay. Four of the five anthraquinones exhibited ’s of about to M. The most effective inhibitors were 2-methoxy-1,4-anthraquinone and 1,4-anthraquinone followed by 9-hydroxy-1,4 anthraquinone and 9-methoxy-1,4-anthraquinone. At lower concentrations the latter anthraquinone stimulated E20M activity. Quinizarin was less inhibitory and 2-hydroxy-1,4-anthraquinone was essentially without effect. Significantly, these studies make evident for the first time that anthraquinones can affect insect E20M activity, and thus insect endocrine regulation and development, and that a relationship between anthraquinone structure and effectiveness is apparent. These studies represent the first demonstrations of anthraquinones affecting any steroid hydroxylase system.
PubDate: Tue, 21 Oct 2014 13:36:38 +000
- Benthic Macroinvertebrates along the Haraz Downstream in Southern Caspian
Sea Basin: In Gradient of the Physicochemical Parameters
Abstract: The Haraz River is one of the most important rivers in the Caspian Sea basin. In order to investigate changes in the taxa abundance composition and feeding groups of the benthic macroinvertebrates, twelve-time sampling was carried out at nine stations along three different sites: (1) before, (2) into, and (3) after Amol City. Results showed impacts of anthropogenic activities caused by the urbanization and development on the occurrence of benthic macroinvertebrates taxa. Families, Hydropsychidae and Heptageniidae at site 1 and Tipulidae at sites 2 and 3, were significantly dominant. The feeding groups of gathering collectors and predators increased from site 1 to site 3, while the filtering collectors and scrapers decreased. Consequently, our data supported the use of the bioindicator concept for Haraz River. Some sensitive (Hydropsychidae, Heptageniidae, Baetidae, and Leuctridae) and tolerant families (Tipulidae and Naididae/Tubificidae) are introduced as potential bioindicators of clean and disturbed river’s area, respectively.
PubDate: Wed, 08 Oct 2014 10:03:16 +000
- Studies on the Vertical Distribution of Ticks of Domestic Animals and
Their Public Health Importance in Nilgiri Hills and Adjoining Areas of
Tamil Nadu State (India)
Abstract: The Nilgiri hills and adjoining downhill areas provide favourable ecological conditions for the propagation of haematophagous arthropods owing to richness in vegetation and animal activities. A study has been undertaken during 2008–2010 on the distribution and abundance of ticks of domestic animals in seven different biotopes. A total of 3,008 domestic animals were examined in areas ranging from an altitude of 300 to 2200 meters above mean sea level (MSL) of which 1,335 (44.5%) animals were having tick infestation. A total of 6,012 adult and immature ticks belonging to 12 species (11 ixodid and one argasid) were collected. Eleven tick species were collected from Kallar area situated downhill eastern slopes of the Nilgiris followed by Burliar area (7 species) located at higher altitudes. From Masinagudi area near to dense forests and scrub jungles, five species were recorded. However, at higher elevations on the hills, Udhagamandalam area, only one species was recorded. Among various tick species recorded in the study, Boophilus microplus was distributed in almost all areas surveyed followed by Haemaphysalis spinigera and Rhipicephalus sanguineus. The factors governing their distribution and epidemiological significance in the transmission of various tick-borne diseases of public health importance are discussed.
PubDate: Wed, 10 Sep 2014 06:27:16 +000
- The Diet and Sexual Differences of the Caspian Bent-Toed Gecko,
Tenuidactylus caspius (Squamata: Gekkonidae), in Northern Iran
Abstract: The Caspian bent-toed gecko, Tenuidactylus caspius, is one of the most common nocturnal lizards of Iran with widespread distribution especially in the northern provinces. This research was done in order to study the diet and sexual dimorphism of this species in Sari County from 5 May to 20 October. During this research, 40 specimens of them including 20 males and 20 females were studied for diet and 140 specimens including 70 adult males and 70 adult females were studied for sexual dimorphism. Prey items identified were insects that belong to 15 species of 8 families and 6 orders. The most common prey items were Culex pipiens and Musca domestica. There is no significant difference between diets of males and females. Results show that the adult males in addition of having the apparent femoral and preanal pores are heavier than females and have larger body, head, and tail length.
PubDate: Mon, 08 Sep 2014 10:49:14 +000
- Life Cycle and Secondary Production of Four Species from Functional
Feeding Groups in a Tropical Stream of South India
Abstract: This study focused on life strategies of species from functional feeding groups (FFGs) found in a tropical stream of the Sirumalai hills, South India. We examined the life cycle and secondary production of species of shredders (Lepidostoma nuburagangai), scrapers (Baetis sp.), collectors (Choroterpes alagarensis), and predators (Neoperla biseriata). In addition, we studied the assemblage structure of functional feeding groups. We found the collectors occupied the highest percentage, followed in turn by scrapers, predators, and shredders. The diversity of FFGs was higher at riffle areas and assemblage with stream substrates differing in each functional group. An asynchronous life cycle was observed for Baetis, C. alagarensis, and N. biseriata, while L. nuburagangai was found in four to five generations per year. We acquired data on secondary production of scraper species of Baetis, which reached the highest values among all investigated species. This observation stresses the importance of scrapers as playing a key role in converting coarse particulate organic matter to fine particulate organic matter with low or high abundances of shredder population and maintaining the food chain in tropical streams.
PubDate: Wed, 20 Aug 2014 05:56:46 +000
- Glycolipids as Potential Energy Molecules during Starvation in Climbing
Perch, Anabas testudineus (Bloch)
Abstract: Glycolipids are membrane lipids which act as cellular markers and also provide energy for the cells. The present study is an attempt to understand whether glycolipids can act as energy sources during fasting. To achieve this, we selected and subjected Anabas testudineus to short-term (15 days) and long-term (60 days) laboratory starvation. We estimated glycolipids biochemically using a standard protocol in six different tissues. Results showed a selective decline in glycolipid concentration in certain tissues, and also an increase was observed in some tissues. Short-term fasting led to a decline in glycolipids in tissues such as brain (), accessory respiratory organ (), pectoral and lateral line muscle. Liver and kidney () reported an increase. Long term starvation also resulted in a decline in tissues such as liver (), kidney (), brain, and accessory respiratory organ. Muscle tissue, that is, both the pectoral () and lateral line muscle (), showed an increase in the glycolipid fraction. This selective decline in glycolipid content of certain tissues suggests a possible utilization of these lipids during starvation and the significant upsurge observed in certain tissues suggests a simultaneous synthesis occurring along the degradation, probably reducing the oxidative stress created by ROS (reactive oxygen species).
PubDate: Sun, 20 Jul 2014 00:00:00 +000
- Climate-Related Variation in Body Dimensions within Four Lacertid Species
Abstract: A close relationship between habitat and external morphology is widespread among many animals, including reptiles. Here, I studied the relationship between abiotic environmental conditions and body size of four lacertid species (Phoenicolacerta laevis, Ophisops elegans, Acanthodactylus boskianus, and Mesalina guttulata) occurring in Israel. I examined the effect of average annual temperature and average annual precipitation on body and limb dimensions, using linear statistical models. Temperature- and precipitation-related geographic clines in body size showed the same trend among all species. Females displayed stronger phenotypic response to temperature gradient than conspecific males, suggesting a sex-specific effect of natural selection. Snout-vent length (SVL) was negatively correlated with temperature, supporting Bergmann’s rule in O. elegans and in female P. laevis and A. boskianus, but not in M. guttulata. Precipitation was positively related to SVL in O. elegans and M. guttulata, and in female P. laevis and A. boskianus. The relative extremity lengths, especially hind limb segments, generally increase towards hot and dry locations, following Allen’s rule. Among the Mediterranean region species (P. laevis, O. elegans) the morphological-environmental link with temperature was stronger than in desert dwellers (A. boskianus, M. guttulata), for which precipitation was the major determinant of spatial variation.
PubDate: Mon, 19 May 2014 09:30:17 +000