13 research outputs found
Patterns in abundance and diversity of faecally dispersed parasites of tiger in Tadoba National Park, central India
BACKGROUND: Importance of parasites in ecological and evolutionary interactions is being increasingly recognized. However, ecological data on parasites of important host species is still scanty. We analyze the patterns seen in the faecal parasites of tigers in the Tadoba National Park, India, and speculate on the factors and processes shaping the parasite community and the possible implications for tiger ecology. RESULTS: The prevalence and intensities were high and the parasite community was dominated by indirect life cycle parasites. Across all genera of parasites variance scaled with the square of the mean and there was a significant positive correlation between prevalence and abundance. There was no significant association between different types of parasites. CONCLUSIONS: The 70 samples analyzed formed 14 distinct clusters. If we assume each of the clusters to represent individual tigers that were sampled repeatedly and that resident tigers are more likely to be sampled repeatedly, the presumed transient tigers had significantly greater parasite loads than the presumed resident ones
Coprophagy by Barking Deer Muntiacus vaginalis (Mammalia: Cetartiodactyla: Cervidae) in Buxa Tiger Reserve, West Bengal, India
A Barking Deer was seen feeding on Asian Elephant’s dung containing partly digested fruits of Dillenia indica at Buxa Tiger Reserve, West Bengal. This case of coprophagy appears to be opportunistic frugivore selection by the deer. </div
Parasitization of a huntsman spider (Arachnida: Araneae: Sparassidae: Heteropoda venatoria) by a mermithid nematode (Nematoda: Mermithidae)
The emergence of a mermithid worm from a huntsman spider Heteropoda venatoria was witnessed at Buxa Tiger Reserve, West Bengal. It appears to be a first record of the spider family Sparassidae serving as a host for a member of the family Mermithidae. </p
Nesting of Lesser Whistling-Duck Dendrocygna javanica (Horsfield, 1821) (Aves: Anseriformes: Anatidae) and broken-wing distraction display at Kamrup District, Assam, India
We observed 13 nesting attempts of the Lesser Whistling-Duck during 2011–2014 at Rani, Kamrup District in Assam, India. Failure in egg laying by the ducks and nest raiding by Grey Mongoose were recorded, while the breeding success was 38.5%. For the first time we witnessed broken wing distraction display exhibited by this species as an anti-predator strategy, which we have recorded here.  </div
Central Cholinergic Neurons Are Rapidly Recruited by Reinforcement Feedback
Summary Basal forebrain cholinergic neurons constitute a major neuromodulatory system implicated in normal cognition and neurodegenerative dementias. Cholinergic projections densely innervate neocortex, releasing acetylcholine to regulate arousal, attention, and learning. However, their precise behavioral function is poorly understood because identified cholinergic neurons have never been recorded during behavior. To determine which aspects of cognition their activity might support, we recorded cholinergic neurons using optogenetic identification in mice performing an auditory detection task requiring sustained attention. We found that a non-cholinergic basal forebrain population—but not cholinergic neurons—were correlated with trial-to-trial measures of attention. Surprisingly, cholinergic neurons responded to reward and punishment with unusual speed and precision (18 ± 3 ms). Cholinergic responses were scaled by the unexpectedness of reinforcement and were highly similar across neurons and two nuclei innervating distinct cortical areas. These results reveal that the cholinergic system broadcasts a rapid and precisely timed reinforcement signal, supporting fast cortical activation and plasticity
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Recent trends in populations of Critically Endangered Gyps vulture population in India
This paper reports results from the eighth of a series of road transect surveys of Gyps vultures conducted across northern, central, western and north-eastern India since the early 1990s. Populations of the White-rumped Vulture Gyps bengalensis, Indian Vulture G. indicus and Slender-billed Vulture G. tenuirostris declined rapidly, beginning in the mid-1990s. The principal cause of the declines was poisoning due to widespread veterinary use of the non-steroidal anti-inflammatory drug diclofenac on cattle. The results of the current survey suggest that, while populations of all three species of vulture remain at a low level with no signs of recovery, they appear to have been approximately stable since veterinary use of diclofenac was banned in the mid-2000s. Population trends in India, where illegal use of diclofenac and legal use of other toxic NSAIDs continues, are compared with more positive trends in Nepal, where the veterinary use of toxic NSAIDs appears to have been reduced to a low level.This research was funded by the Royal Society for the Protection of Birds, United Kingdom
Suture fixation of migrated septal occluder device to prevent further migration: a simple surgical technique
<p>Abstract</p> <p>As the use of percutaneous intervention is increasing for the closure of the atrial septal defect, the procedure related complications are also on rise, migration of the device being most common. The migrated devices with failed percutaneous retrieval must be removed surgically under cardiopulmonary bypass. During establishment of cardiopulmonary bypass, the handling of heart may cause further migration of the device into other chambers of heart which leads to difficulty in finding and retrieval of the device. The authors propose a simple and unique technique to prevent further migration of the septal occluder device.</p
The race to prevent the extinction of South Asian vultures
Gyps vulture populations across the Indian subcontinent collapsed in the 1990s and continue to decline. Repeated population surveys showed that the rate of decline was so rapid that elevated mortality of adult birds must be a key demographic mechanism. Post mortem examination showed that the majority of dead vultures had visceral gout, due to kidney damage. The realisation that diclofenac, a non-steroidal anti-inflammatory drug potentially nephrotoxic to birds, had become a widely used veterinary medicine led to the identification of diclofenac poisoning as the cause of the decline. Surveys of diclofenac contamination of domestic ungulate carcasses, combined with vulture population modelling, show that the level of contamination is sufficient for it to be the sole cause of the decline. Testing on vultures of meloxicam, an alternative NSAID for livestock treatment, showed that it did not harm them at concentrations likely to be encountered by wild birds and would be a safe replacement for diclofenac. The manufacture of diclofenac for veterinary use has been banned, but its sale has not. Conseuently, it may be some years before diclofenac is removed from the vultures’ food supply. In the meantime, captive populations of three vulture species have been established to provide sources of birds for future reintroduction programmes