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1.
Reproductive behaviour of free-ranging dogsCanis familiaris Linnaeus, 1758 was studied in a village in the state of West Bengal, India. Increased synchronized breeding was the most striking feature of this study. October (late monsoon) represented the peak period of mating for the feral dogs. Of all courting males, only 41% were observed to mount and copulate. On average, each male mounted 5.47 ± 2.49 (mean ± SD) times per hour. Of all mountings, only 10% were successful matings, ie copulatory ties. There was a negative correlation between the number of courting males and the number of successful copulations. The average duration of copulatory tie was 15.73 ± 7.75 min. Several factors interrupting the duration of copulatory ties were identified. December was the peak period of pup rearing. Mean litter size was 5.70 ± 2.03 with a male-biased sex ratio 1.41:1. Only a single annual breeding cycle recorded here differed from the previous studies on European and American dogs. Mothers spent most of the time with their pups at the dens during the early stage of rearing. The duration of time spent at dens by mothers was minimum when the pups were highly mobile at the age of 10 weeks. The lactating mothers were observed to be more aggressive immediately following litter production. Typically, an old adult male remained near the den as a ‘guard’. 相似文献
2.
We conducted a field study of diets of three sympatric large carnivores, the tiger Panthera tigris , the leopard Panthera pardus and the dhole Cuon alpinus in Bandipur Tiger Reserve, India, based on analyses of 381, 111 and 181 scats, respectively. The frequency of occurrence of prey items in scats was converted to relative biomass and number of prey consumed using regression equations based on earlier feeding trials. The results showed that although these predators kill ∼11–15 species of vertebrate prey, relatively abundant ungulate species provide 88–97% of biomass consumed by them. Although the dietary niche overlap among the three species was high (Pianka's index of 0.75–0.93), some specialized predation was observed. The largest ungulates, gaur Bos gaurus and sambar Cervus unicolor , provided 73% of biomass consumed by tigers, whereas medium-sized chital Axis axis and wild pig Sus scrofa formed 65 and 83% of the biomass intake of leopards and dholes, respectively. In terms of the relative numbers of prey animals killed by the three predators, chital, which is the most abundant prey species, dominated their diets (tiger=33%, leopard=39% and dhole=73%). The results of the study, in conjunction with earlier work, support the prediction that abundance of ungulate prey species, as well as their availability in different size classes, are both critical factors that facilitate sympatry among the three predators. 相似文献
3.
Ghosh Shubhadeep Satishkumar Mamidi Manas Hoshalli Munivenkatappa Rohit Prathibha Abdussamad Eruppakkottil Median Gopalakrishnan Achamveetil 《Environmental Biology of Fishes》2021,104(11):1421-1432
Environmental Biology of Fishes - With the lack of information available globally on the reproductive biology of Sphyraena putnamae, the present study was performed using 908 individuals landed... 相似文献
4.
Himanshu S. Palei Tilak Pradhan Hemanta K. Sahu Anup K. Nayak 《Proceedings of the Zoological Society》2016,69(2):181-188
Knowledge on the occurrence and distribution of species is crucial for designing and evaluating conservation strategies within a geographical region. Similipal Tiger Reserve though confined to a small area needs information on the diversity and abundance of mammalian fauna to ensure conservation of tiger. Thus, we aimed to assess the diversity and abundance of medium to large sized mammals in Similipal Tiger Reserve by using remotely triggered camera traps. A total of 6413 camera trap days at 187 trap stations were deployed from November 2012 to July 2013 to estimate the status of mammal. We obtained 3763 independent photographs and detected 24 species of mammals. The relative abundance index of each mammalian species was calculated. Leopard (Panthera pardus) was the most abundant carnivore while barking deer (Muntiacus muntjac) was the most abundant prey. Anthropogenic activities like hunting, livestock grazing and free ranging domestic dogs were found to be the detrimental factors for the existing mammalian species. These activities should be addressed through conservation and development perception with an interdisciplinary approach, incorporating social and ecological components cautiously. 相似文献
5.
Subhadeep Bhattacharjee Vinod Kumar Mithileshwari Chandrasekhar Manjari Malviya Andre Ganswindt Krishnamurthy Ramesh Kalyanasundaram Sankar Govindhaswamy Umapathy 《PloS one》2015,10(6)
Tiger (Panthera tigris), an endangered species, is under severe threat from poaching, habitat loss, prey depletion and habitat disturbance. Such factors have been reported causing local extermination of tiger populations including in one of the most important reserves in India, namely Sariska Tiger Reserve (STR) in northwestern India. Consequently, tigers were reintroduced in STR between 2008 and 2010, but inadequate breeding success was observed over the years, thus invoking an investigation to ascertain physiological correlates. In the present study, we report glucocorticoid stress responses of the reintroduced tigers in relation to anthropogenic disturbance in the STR from 2011 to 2013. We found anthropogenic disturbance such as encounter rates of livestock and humans, distance to roads and efforts to kill domestic livestock associated with an elevation in fecal glucocorticoid metabolite (fGCM) concentrations in the monitored tigers. In this regard, female tigers seem more sensitive to such disturbance than males. It was possible to discern that tiger’s fGCM levels were significantly positively related to the time spent in disturbed areas. Resulting management recommendations include relocation of villages from core areas and restriction of all anthropogenic activities in the entire STR. 相似文献
6.
Sahidur Rahman 《Archives Of Phytopathology And Plant Protection》2013,46(5):608-619
This study was conducted with a view to understand the effect of plant characteristics on the incidence of pests on most popular jute varieties, viz. JRO-524, JRO-632, JRO-878, JRO-7835 of olitorius jute and JRC-212, JRC-321, JRC-4444, JRC-7447 of capsularis jute. Correlation studies of plant characteristics with pest incidence in jute (Corchorus spp.) revealed that the basal girth of plant exhibited a positive significant relationship with the incidence of Apion corchori Marshall but not with other pests such as jute semilooper (Anomis sabulifera Guen.), Bihar hairy caterpillar (Spilarctia obliqua Wlk.), grey weevil (Myllocerus discolor Bohemus) and yellow mite (Polyphagotarsonemus latus Banks). However, plant height showed positive correlation with the incidence of all the major pests of jute. Leaf characteristics (number of leaves/plant, leaf area, leaf thickness, moisture and chlorophyll content of leaves of all the varieties recorded at three different growth stages, i.e. at 50, 80 and 110 days after sowing), number of leaves/plant had positive and significant relationship with the incidence of all the pests except stem weevil. However, leaf area and moisture content of leaves showed significant positive relationship with the incidence of yellow mite. Leaf moisture also showed a positive role on the infestation of grey weevil. Leaf thickness and chlorophyll content of leaves and stem, fibre thickness and moisture content of stem did show any significant effect on pest's incidence. Upon comparing the plant characteristics between the two jute species, olitorius varieties had greater fibre thickness than that of capsularis varieties but fibre thickness had no significant impact on incidence of pests. 相似文献
7.
8.
Very little is known about prey selection by the Indian tiger Panthera tigris tigris in tropical dry deciduous forests or in wild herbivore-depleted habitats with high livestock pressures. We undertook a short-term study in a large south Indian tiger reserve and examined two intensive study areas (SA's) from October 1998 – June 1999. In each area, herbivore sightings were recorded, scats were collected, and wild prey and livestock kills documented. Chital, wild boar and sambar were the most abundant among the wild herbivores in the study area. Scat analysis revealed wild boar (Sus scrofa) being the most common prey followed by chital (Axis axis) and sambar (Rusa unicolor). Livestock comprised less than 7% of diet intake. Here, the tigers consumed a lower mean prey mass (56.3 kg) than in other reserves. Our study suggests that in tropical dry deciduous forests with low natural prey density, smaller prey species, and high livestock biomass, tigers preferentially kill smaller prey and generally avoid livestock predation. 相似文献
9.
Anthropometric and body composition characteristics during pregnancy: A study from West Bengal,India
Arnab Ghosh 《HOMO》2012,63(3):233-240
The present cross-sectional study was aimed at investigating changes in anthropometric, body composition and blood pressure characteristics during pregnancy. A total of 406 healthy, pregnant women aged between 16 and 33 years participated in the study. Pregnant women were recruited from the outpatient department of the two-referral hospital in Bolpur subdivision of Birbhum district, West Bengal, India. Anthropometric measures such as height, weight, three circumferences and skinfold thickness at four sites (biceps, triceps, subscapular and suprailaic) were obtained using standard techniques. Percentages of body fat (%BF), intra abdominal visceral fat (IVF), basal metabolic rate (BMR) and body mass index (BMI) were measured using an Omron body fat analyser. Two forenoon blood pressure measurements were also taken and averaged for analysis. Subjects were categorized into three trimester groups: Group I, n = 30; Group II, n = 163; and Group III, n = 213. ANOVA with Scheffe's post-hoc test revealed that Group I had significantly lower mean than both Group II and Group III for systolic blood pressure and IVF, whereas Group I had significantly lower mean than Group III for BMI, BMR, %BF, diastolic blood pressure and skinfolds. The mean change in maternal weight from the first to the third trimester was merely 3 kg. Mean waist circumference varied from the first to the third trimester but not from the first to the second trimester. Furthermore, significantly increased systolic and diastolic blood pressure was observed across the trimesters. However, longitudinal studies involving interaction of body fat topography and pregnancy-induced hormones are required to further our understanding of gestation mechanism. 相似文献
10.
Karmakar B Yakovenko K Kobyliansky E 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》2002,60(3):273-292
Five hundred families from five different endogamous populations encompassing the main social rank in the caste hierarchy of the same geographical area of West Bengal, India, were analyzed to present variation in qualitative pattern types on fingers and palms. Sex dimorphism, homogeneous in all populations, suggests common characteristics of dermatoglyphic patterns. The pattern types are not uniformly distributed on 10 fingers and palmar configurational areas. However, most of these observations are homogeneous in nature, in both sexes among 5 populations. But the two sets of results on fingers and palms are not exactly the same. Palmar dermatoglyphic relationship reflects the better caste affinities, perhaps due to embryological development, having relatively a longer growth period compared to fingers (Cummins 1929). The present findings indicate that the qualitative dermatoglyphic affinities conform to the known ethnohistorical background of these populations, which correspond also to the results of quantitative dermatoglyphics as well as serological and biochemical markers of these populations. These observations indicate that these population groups have a common genetic background and thus traditional grouping of Indian populations on the basis of caste hierarchy may not be a reflection of the genetic origin of the population. In dermatoglyphic affinities, both qualitative and quantitative traits therefore may be quite useful in tracing the ethnohistorical background of these populations. 相似文献
11.
In this study of the genetics of dermatoglyphic asymmetry, we collected bilateral finger and palm prints of 824 individuals from 200 families including 2 generations from an endogamous caste (Vaidya) in Barasat, North 24-Parganas District, West Bengal. Two main types of asymmetry (fluctuating asymmetry and directional asymmetry) were calculated between the two hands. The study includes familial correlation between first-degree relatives, principal-components analysis, and maximum-likelihood-based heritabilities (by pedigree analysis). We found, first, that familial correlations in all possible pairs of relationships (except spouse correlation) were weak but positive; some were even statistically significant. No indication of assortative mating was observed, but the influence of maternal environment could not be discarded. The results also showed that X-chromosome linkage does not seem to be involved. A second major finding is that five principal factors could be extracted from all these asymmetric traits, explaining 74.207% of the overall cumulative variance. Asymmetry of finger and palmar areas were clearly separated by factor. In addition, the heritabilities of the extracted five factors were in the range of 8-24%. These estimates are in agreement with some previously published data. The heritabilities of the factors describing palmar asymmetry are slightly lower than those describing finger asymmetry. The present results support the hypothesis that both types of asymmetry have a genetic basis and are influenced by the intrauterine environment. 相似文献
12.
Sunil Kumar Pal 《Acta theriologica》2001,46(1):69-78
A population of urban free-ranging dogsCanis familiaris Linnaeus, 1758 was studied in Katwa, West Bengal, India. The analysis of changes in the density of the dog population over a period of 4 years revealed a considerable stability of this population. Mean (±SD)2 seasonal population density was 185±19 dogs/km2, ranging from 156 to 214 dogs/km2. A sex ratio of 1.37∶1 in favour of male was recorded in this study. High mortality (67%) occurred under the age of 4 months, and 82% mortality occurred within the age of 1 year. Among the adults, 24% mortality under the age of 2.6 year was recorded. Only a single breeding cycle and synchronization of breeding was observed. Immigration was observed as a crucial factor affecting the stability of this population. 相似文献
13.
Aeromycoflora studies above an “Aman” variety of paddy (Oryza saliva L.) were carried out for two consecutive seasons, in 1990 and 1991, in the vicinity of Barrackpore, West Bengal, by means of the culture plate exposure technique. A more or less uniform spore concentration was observed during the early part of the vegetative stages in 1990 with an abrupt increase and peak during the maximum vegetative growth period. In 1991, a uniform spore count was found up until the flowering stages. A gradual increase in spore count after flowering was recorded in both seasons with the highest peaks during harvesting, followed by a sudden decrease after the harvest. The dominant genera isolated were Aspergillus, Currularia, Cladosporium and Penicillium. Aspergillus appeared in high concentrations from the very beginning of the crop season up to the flowering stages, with a gradual fall after flowering, while Cladosporium showed the reverse pattern. Currularia and Penicillium occurred regularly throughout the crop season. Phytopathogenic types were represented by Helminthosporium oryzae, Fusarium, Altemaria and Nigrospora. Helminthosporium oryzae appeared in the air when the plants attained appreciable vegetative growth, being seen as “brown spots” on the foliage, and reaching peak concentration during harvesting. Fusarium in contrast to Altemaria appeared regularly in the air except during the later part of vegetative growth. Nigrospora was recorded only occasionally. A considerable number of “Sterile Forms” were present throughout both seasons. 相似文献
14.
A comparative survey of airborne fungal spores in fiveindoor and five outdoor environments in Burdwan, WestBengal, India, was carried out for a period of twoyears using rotorod samplers and sedimentation plates(culture plate). A total of 29 spore types wereidentified, of which three were Phycomycetous (Mucor, Rhizopus, Syncephalastrum), one Ascomycetous(Chaetomium), one Basidiomycetous (Ganoderma) and the remainder were Fungi Imperfecti. The results revealed lowest count during summer andmaximum during the rainy season. Aspergilluswas quite abundant in all the environments surveyed. The predominance of Aspergillus, Curvularia,Alternaria, Cladosporium, Drechslera, Fusarium in allthe surveyed environments has been attributed to theirability to grow in various substrata. The occurrenceof Cladosporium in the winter months suggestthat it is sensitive to high temperature. Allspore types were common in both environmentsexcept Bispora, Cercospora, Papularia, Spegazzinia, Trichothecium in the outdoor sites. Acorrelation has been made between the volumetriccomposition of airspora and the incidence of seasonalmold allergy. 相似文献
15.
This paper provides a brief account of 40 plants associated with herbal remedies among the Lodhas, a tribe of Midnapur district, West Bengal, India. Reports from informants were obtained during field studies between 1977 and 1982. The data are compared with information obtained from some other tribal societies like the Santals and the Oraons inhabiting neighbouring regions. The Lodhas have had a rich herbal folklore, but this is fading due to increasing acculturation and depletion of plant cover. 相似文献
16.
Apurba Debbarma Soumitra Pandit Surajit Baidya Subhas Chandra Mandal Partha Sarathi Jana 《Biological Rhythm Research》2018,49(5):655-662
The present study was conducted to determine the prevalence of hard tick infestations in cattle of West Bengal from July 2015 to June 2016. The prevalence of hard tick infestations was studied in relation to sex and age of animals and seasonal changes in a year. Cattle of selected places were examined carefully for the presence of ticks and in positive cases ticks were collected manually and identified on the basis of morphological characters. A total of 310 cattle were examined and out of which, 130 (41.93%) cattle were found to be infested with hard ticks and the prevalent species were Rhipicephalus (Boophilus) sp., Hyalomma sp. and Haemaphysalis sp. of ticks. A significantly (p < 0.01) higher infestation was observed in female cattle (43.30%) than males (35.71%). Age-wise highest prevalence of tick infestations was found in <1 year (65%) age group followed by >3 years age group (36.8%) and 1–3 years (35.63%) age group, respectively. Seasonally, the prevalence of hard ticks was highest (p < 0.01) in monsoon (59.25%) and lowest in winter (27.09%). The study revealed that the prevalence of Rhipicephalus (Boophilus) sp. (32.25%) was significantly (p < 0.01) higher compared to Hyalomma (12.58%) and Haemaphysalis sp. (3.22%). The observations of the present study would provide a basis for evolving effective control strategy for the management of ticks in bovines of West Bengal. 相似文献
17.
B N Mukherjee H Walter K C Malhotra R Chakraborty P Sauber S Banerjee M Roy 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》1987,45(3):239-254
Ten endogamous population groups of West Bengal (India)--Rabhas, Garos, Mechs, Rajbanshis, Jalia Kaibartas, Bagdis, Lodhas, Mundas, Brahmins, Vaidyas--have been typed for twelve polymorphic systems: ABO, Gm, Km, Hp, Cp, Tf, Alb, Hb, aP, EsD, AK and PGM1. The results are compared with those obtained on other Indian populations. Serological and anthropometric data, which have been included into population comparisons, reveal a considerable genetic variability of the groups under study. This variability is obviously connected with the population history of West Bengal. 相似文献
18.
B. B. Jana 《Hydrobiologia》1978,61(2):135-143
Estimates of planktonic growth kinetics in relation to the thermal environment were made over a two year period in three hot springs and one cold one located in West Bengal, India. A very characteristic feature of the Saubhagya Kund (43–49°C) and Papahara (46–51°C) was the abundance of phytoplankton, always dominated by blue-green algae. This situation changed in the other two springs where zooplankton was an essential component. The determination of the species diversity index indicated that the graph of cumulative species of plankton versus logarithm of individuals was roughly linear in Saubhagya Kund and Papahara, whereas in the other two a logistic curve was the result. The seasonal distribution of Myxophyceae/Phytoplankton was dependant upon the annual phosphorous cycle (P < 0.0001) in all the thermal waters studied. That the population dynamics of diatoms responded inversely to the level of phosphate (P < 0.05) has been clearly manifested in Swetganga (37–46°C). The variation in the silicate content of the water throughout the year has been found responsible for the seasonal succession of diatoms in some of the waters (P < 0.001). The multiple correlation between phosphate, silicate, dissolved oxygen and pH and Myxophyceae/Phytoplankton was significant in the case of Papahara (P < 0.01) and Swetganga (P < 0.05). Similarly, the multiple correlation between these factors and Bacillariophyceae was significant in Saubhagya Kund (P < 0.01). In the non-thermal water Jibatsa Kund (22–39°C), the multiple correlation between these factors and Phytoplankton was, however, not significant (P > 0.05). 相似文献
19.
Ranjit K. Banerji 《Palaeogeography, Palaeoclimatology, Palaeoecology》1984,45(1):49-73
The Bengal Basin is known for the extensive development of a thick Cretaceous— Tertiary sedimentary sequence in the eastern part of India. The basin has undergone several phases of transgressions, regressions, periodic uplifts and localised negative movements throughout the period of its evolution. The sedimentation up to the end of the Eocene was largely under the influence of a major transgressive phase which was later replaced by a regressive phase on account of the uplift and resulting marine retreat. in this paper, an analysis of the microfaunal distribution, biofacies and sedimentary and tectonic history is made for reconstruction of the palaeoenvironmental conditions and palaeogeography of the Bengal Basin relating to the post-Eocene regressive phase of evolution.During the Oligocene—Early Miocene, the open marine conditions existing since the Eocene were progressively modified on account of the regression into more brackish, lagoonal and estuarine types. A typical prograding delta started to spread over a large part of the marginal area of the basin. The rocks of the Barail Group, formed under the transitional environments of the delta, are found to occur in almost all the major geo-provinces of the basin. The sedimentary environments and characteristics of the rocks were ultimately controlled by the configurations of the respective geo-provinces. The negative movements in the Miocene along certain marginal areas were associated with the marine transgressive phase giving rise to the Surma Group. This transgressive phase was, however, short lived and its impact was not equally felt in all areas. The northeastern region was still uplifted which favoured an almost continuous existence of the deltaic phase.By the end of Miocene a greater part of the basin underwent a strong tectonic upheaval which was possibly the precursor of the main Himalayan orogeny. The intermontane depressions formed in the uplifted areas were the depositional sites for the Tipam Group and younger beds in Plio-Pleistocene times. The rapidly eroded debris from the highlands spread over a wide area towards the south under the influence of the river system of the Ganga and Brahmaputra which has transformed the original basinal areas into a large modern delta complex. 相似文献
20.
B. B. Jana 《International Review of Hydrobiology》1973,58(1):127-143
The paper describes a year-round limnoplanktonic study of a freshwater pond in West Bengal, India. Always predominant over zooplankton, phytoplankton demonstrates three peaks. The relationships between pH and phytoplankton, between phosphate and green algae and between rotifers and diatoms are significant. The role of physico-chemical factors in determining different planktonic population is discussed. The multiple correlation between several physico-chemical factors and phytoplankton percentage is not significant. 相似文献