Displaying publications 61 - 80 of 216 in total

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  1. Assessing diet of the rufous-winged philentoma (philentoma pyrhoptera) in lowland tropical forest using next-generation sequencing
    Mohammad Saiful Mansor, Shukor Md. Nor, Rosli Ramli
    Sains Malaysiana, 2018;47:1045-1050.
    Dietary study provides understanding in predator-prey relationships, yet diet of tropical forest birds is poorly understood.
    In this study, a non-invasive method, next-generation sequencing (Illumina MiSeq platform) was used to identify prey in
    the faecal samples of the Rufous-winged Philentoma (Philentoma pyrhoptera). Dietary samples were collected in lowland
    tropical forest of central Peninsular Malaysia. A general invertebrate primer pair was used for the first time to assess
    diet of tropical birds. The USEARCH was used to cluster the COI mtDNA sequences into Operational Taxonomic Unit (OTU).
    OTU sequences were aligned and queried through the GenBank or Biodiversity of Life Database (BOLD). We identified
    26 distinct arthropod taxa from 31 OTUs. Of all OTUs, there was three that could be identified up to species level, 20 to
    genus level, three to family level and five could not assigned to any taxa (the BLAST hits were poor). All sequences were
    identified to class Insecta belonging to 18 families from four orders, where Lepidoptera representing major insect order
    consumed by study bird species. This non-invasive molecular approach provides a practical and rapid technique to
    understand of how energy flows across ecosystems. This technique could be very useful to screen for possible particular
    pest insects consumed by insectivores (e.g. birds and bats) in crop plantation. A comprehensive arthropod studies and
    local reference sequences need to be added to the database to improve the proportion of sequences that can be identified.
    Matched MeSH terms: Birds
  2. Fulltext Isolation of Mycobacterium avium and other nontuberculous mycobacteria in chickens and captive birds in peninsular Malaysia
    Sattar A, Zakaria Z, Abu J, Aziz SA, Rojas-Ponce G
    BMC Vet Res, 2021 Jan 07;17(1):13.
    PMID: 33413380 DOI: 10.1186/s12917-020-02695-8
    BACKGROUND: Mycobacterium avium complex (MAC) causes a chronic infectious in the birds known as avian mycobacteriosis. Almost all species of the birds are susceptible to MAC which consists of two closely related species of mycobacteria, that is, M. avium and M. intracellulare. This study aimed to determine the occurrence of Mycobacterium avium subsp. avium (MAA) in chickens and captive birds in selected states of Peninsular Malaysia.

    RESULTS: A 300 fecal samples were collected from village chickens (n = 100), layer chickens (n = 100) and captive birds (n = 100). Fecal samples were split into two aliquots for microbiological and molecular detection of MAA. Microbiology detection consisted of microscopy (Ziehl-Neelsen staining) and culture of samples decontaminated with 1% Cetylperidinium chloride and vancomycin, nalidixic acid and amphotericin B (VNA) antibiotic cocktail [vancomycin (VAN) 100 μg/ml, nalidixic acid (NAL) 100 μg/ml and amphotericin B (AMB) 50 μg/ml] onto Löwenstein-Jensen (L-J). Molecular detection (PCR-IS901) was performed to detect MAA DNA from the feces and PCR-16S rRNA and IS901 for identification of genus Mycobacterium and Mycobacterium avium sub species avium isolated onto L-J. All samples (296) were AFB negative smear. M. avium was isolated in 0.3% (1/296) samples by culture and detected in 2.5% (6/242) samples by PCR (IS901). Other mycobacteria were found in 1.7% (5/296) chickens. Of five isolates, two were identified as Mycobacterium terrae and M. engbaekii and remaining isolates were not sequenced. Birds positive for M. avium included White Pelican (n = 1) Black Hornbill (n = 1), Macaw (n = 2), Cockatoo (n = 2) and village chicken (n = 1).

    CONCLUSION: It is concluded that chickens and birds were infected with M. avium in selected areas of Peninsular Malaysia. Although, PCR is rapid, reliable and cost effective method for detection of M. avium in a subclinical stage, the culture of the avian feces should still be used as a reference test for the diagnosis of avian tuberculosis.

    Matched MeSH terms: Birds
  3. Seroprevalence, associated risk factors and hematological impacts of toxoplasmosis in small ruminants of Multan, Punjab-Pakistan
    Ullah MZ, Awais MM, Akhtar M, Anwar MI, Navid MT, Khan I, et al.
    Trop Biomed, 2018 Dec 01;35(4):1028-1040.
    PMID: 33601850
    Toxoplasmosis is a protozoal infection of zoonotic potential with worldwide geographical distribution which affects nearly all warm-blooded animals including mammals and birds. Keeping in view, this study was conducted to determine the seroprevalence of toxoplasmosis along with associated risk factors and its haematological impacts in small ruminants of district Multan, Pakistan. In this study, a total of 250 sera samples collected from sheep (n=125) and goats (n=125) from three tehsils of Multan were examined using commercially available Latex agglutination test kit for the presence of anti-T. gondii antibodies. The haematological profiles of Toxoplasma seropositive and seronegative animals were determined by using automated haematology analyser. Overall seroprevalence of toxoplasmosis in small ruminants was 42.80% with a higher prevalence rate (44.80%) in sheep as compared to goats (40.80%). Sex, existence of co-morbid conditions, feeding pattern and presence of pet cats and dogs were identified as significant (P<0.05) risk factors associated with the presence of antibodies against toxoplasmosis. The breed was found to be a significant (P=0.026) risk factor for the seroprevalence of toxoplasmosis in goats but not in sheep. Haematological analysis revealed significantly altered leukocytic counts (P<0.05) in seropositive sheep and goats as compared to seronegative ones. Our findings showed that small ruminants of the Multan District in Pakistan are toxoplasma seropositive and may pose a serious threat of public health concern in the region.
    Matched MeSH terms: Birds
  4. Fulltext The species composition of thrips (insecta: thysanoptera) inhabiting mango orchards in pulau pinang, malaysia
    Aliakbarpour H, Rawi CS
    Trop Life Sci Res, 2012 May;23(1):45-61.
    PMID: 24575225 MyJurnal
    A field study was conducted at two localities on Pulau Pinang, Malaysia, during two consecutive mango flowering seasons in 2009 to identify variations in the species composition of thrips infesting treated and untreated mango (Mangifera indica L.) orchards. The CO2 immobilisation technique and the cutting method were used to recover different thrips species from mango panicles and weed host plants, respectively. The mango panicles and various weed species within the treated orchard were found to harbour four thrips species from the family Thripidae. These species were identified as Thrips hawaiiensis (Morgan), Scirtothrips dorsalis (Hood), Frankliniella schultzei (Trybom) and Megalurothrips usitatus (Bagnall). The weed species Mimosa pudica, Cleome rutidosperma, Echinochloa colonum, Borreria laevicaulis, Veronia cinerea and Asystasia coromandeliana served as additional hosts to these thrips. Six thrips species were found in the untreated orchard. These species included Thrips palmi (Karny), Haplothrips sp. (Amyot and Serville) and the four thrips species found in the treated orchard. A brief description of the larvae for each genus is provided.
    Matched MeSH terms: Birds
  5. Fulltext Low-Slow-Small (LSS) Target Detection Based on Micro Doppler Analysis in Forward Scattering Radar Geometry
    Musa SA, Raja Abdullah RSA, Sali A, Ismail A, Rashid NEA
    Sensors (Basel), 2019 Jul 29;19(15).
    PMID: 31362452 DOI: 10.3390/s19153332
    The increase in drone misuse by civilian apart from military applications is alarming and need to be addressed. This drone is characterized as a low altitude, slow speed, and small radar cross-section (RCS) (LSS) target and is considered difficult to be detected and classified among other biological targets, such as insects and birds existing in the same surveillance volume. Although several attempts reported the successful drone detection on radio frequency-based (RF), thermal, acoustic, video imaging, and other non-technical methods, however, there are also many limitations. Thus, this paper investigated a micro-Doppler analysis from drone rotating blades for detection in a special Forward Scattering Radar (FSR) geometry. The paper leveraged the identified benefits of FSR mode over conventional radars, such as improved radar cross-section (RCS) value irrespective of radar absorbing material (RAM), direct signal perturbation, and high resolutions. To prove the concept, a received signal model for micro-Doppler analysis, a simulation work, and experimental validation are elaborated and explained in the paper. Two rotating blades aspect angle scenarios were considered, which are (i) when drone makes a turn, the blade cross-sectional area faces the receiver and (ii) when drone maneuvers normally, the cross-sectional blade faces up. The FSR system successfully detected a commercial drone and extracted the micro features of a rotating blade. It further verified the feasibility of using a parabolic dish antenna as a receiver in FSR geometry; this marked an appreciable achievement towards the FSR system performance, which in future could be implemented as either active or passive FSR system.
    Matched MeSH terms: Birds
  6. Fulltext Comparative study of understorey birds diversity inhabiting lowland rainforest virgin jungle reserve and regenerated forest
    Nor Hashim E, Ramli R
    ScientificWorldJournal, 2013;2013:676507.
    PMID: 24453888 DOI: 10.1155/2013/676507
    A comparative study of understorey birds inhabiting different habitats, that is, virgin jungle reserve (VJR) and regenerated forest (RF), was conducted in Ulu Gombak Forest Reserve and Selangor and Triang Forest Reserve, Negeri Sembilan, Peninsular Malaysia. The objective of this study was to assess the diversity of understorey birds in both habitats and the effects of forest regeneration on the understorey bird community. The mist-netting method was used to capture understorey birds inhabiting both habitats in both locations. Species composition and feeding guild indicated that understorey bird populations were similar in the two habitats. However, the number of secondary forest species such as Little spiderhunter (Arachnothera longirostra) in VJR is increasing due to its proximity to RF. This study discovered that RFs in both study areas are not yet fully recovered. However, based on the range of species discovered, the RFs have conservation value and should be maintained because they harbour important forest species such as babblers and flycatchers. The assessment of the community structure of understorey birds in VJR and RF is important for forest management and conservation, especially where both habitats are intact.
    Matched MeSH terms: Birds/classification*
  7. Effects of logging and recovery process on avian richness and diversity in hill dipterocarp tropical rainforest-Malaysia
    Husin MZ, Rajpar MN
    J Environ Biol, 2015 Jan;36 Spec No:121-7.
    PMID: 26591891
    The effects of logging and recovery process on avian richness and diversity was compared in recently logged and thirty year post-harvested hill dipterocarp tropical rainforest, using mist-netting method. Atotal of 803 bird individuals representing 86 bird species and 29 families (i.e., 37.90% from recently logged forest and 62.10% from thirty year post-harvested forest) were captured from October 2010 to September, 2012. Twenty one bird species were commonly captured from both types of forests, 37 bird species were caught only in thirty year post-harvested forest and 28 bird species were caught only from recently logged forest. Arachnothera longirostra--Little Spiderhunter, Malacopteron magnum--Rufous-crowned Babbler, Alophoixus phaeocephalus -Yellow-bellied Bulbul and Meiglyptes tukki--Buff-necked Woodpecker were the most abundant four bird species in the thirty year post-harvested forest. On the contrary, seven bird species, i.e., Trichastoma rostratum - White-chested Babbler, Lacedo pulchella - Banded Kingfisher, Picus miniaceus--Banded Woodpecker, Enicurus ruficapillus - Chestnut-naped Forktail, Anthreptes simplex--Plain Sunbird, Muscicapella hodgsoni--Pygmy Blue Flycatcher and Otus rufescens--Reddish Scope Owl were considered as the rarest (i.e., each represented only 0.12%). Likewise, A. longirostra, Pycnonotus eythropthalmos - Spectacled Bulbul, P. simplex--Cream-vented Bulbul and Merops viridis--Blue-throated Bee-eater were the most dominant and Copsychus malabaricus--White-rumped Shama Eurylaimus javanicus--Banded Broadbill /xos malaccensis - Streaked Bulbul and Harpactes diardii--Diard's Trogon (each 0.12%) were the rarest bird species in recently logged forest. CAP analysis indicated that avian species in thirty year post-harvested forest were more diverse and evenly distributed than recently logged forest. However, recently logged forest was rich in bird species than thirty year post- harvested forest. The results revealed that logging and retrieval process affect bird species richness and diversity. However, bird species may respond differently from habitat to habitat, i.e., forest logging causes disturbance of some avian species while recovery process may replace the loss of vegetation and harbour a wide array of avian species richness and diversity.
    Matched MeSH terms: Birds/classification*
  8. Monitoring of heavy metal pollution in urban and rural environments across Pakistan using House crows (Corvus splendens) as bioindicator
    Iqbal F, Ayub Q, Wilson R, Song BK, Talei A, Yeong KY, et al.
    Environ Monit Assess, 2021 Mar 30;193(4):237.
    PMID: 33783594 DOI: 10.1007/s10661-021-08966-7
    A widely distributed urban bird, the house crow (Corvus splendens), was used to assess bioavailable heavy metals in urban and rural environments across Pakistan. Bioaccumulation of arsenic (As), zinc (Zn), lead (Pb), cadmium (Cd), nickel (Ni), iron (Fe), manganese (Mn), chromium (Cr), and copper (Cu) was investigated in wing feathers of 96 crows collected from eight locations and categorized into four groups pertaining to their geographical and environmental similarities. Results revealed that the concentrations of Pb, Ni, Mn, Cu, and Cr were positively correlated and varied significantly among the four groups. Zn, Fe, Cr, and Cu regarded as industrial outputs, were observed in birds both in industrialized cities and in adjoining rural agricultural areas irrigated through the Indus Basin Irrigation System. Birds in both urban regions accrued Pb more than the metal toxicity thresholds for birds. The house crow was ranked in the middle on the metal accumulation levels in feathers between highly accumulating raptor and piscivore and less contaminated insectivore and granivore species in the studied areas,. This study suggests that the house crow is an efficient bioindicator and supports the feasibility of using feathers to discriminate the local pollution differences among terrestrial environments having different levels and kinds of anthropogenic activities.
    Matched MeSH terms: Birds
  9. Biomonitoring of heavy metals in the feathers of House crow (Corvus splendens) from some metropolitans of Asia and Africa
    Iqbal F, Wilson R, Ayub Q, Song BK, Krzeminska-Ahmedzai U, Talei A, et al.
    Environ Sci Pollut Res Int, 2023 Mar;30(13):35715-35726.
    PMID: 36536201 DOI: 10.1007/s11356-022-24712-z
    Urban-dwelling birds can be useful biomonitors to assess the impact of the urbanisation on both public and wildlife health. Widely distributed urban bird species, the House crow, was studied for heavy metal accumulation levels from nine cities of South Asia, Southeast Asia and Africa that border the Indian Ocean. Feathers were spectroscopically investigated for the deposition of ten heavy metals, i.e. As, Zn, Pb, Cd, Ni, iron Fe, Mn, Cr, Cu and Li. Fe and Zn were found to be the most prevalent metals in all sites. Measured concentrations of Pb (4.38-14.77 mg kg-1) overall, and Fe (935.66 mg kg-1) and Cu (67.17 mg kg-1) at some studied sites were above the toxicity levels reported lethal in avian toxicological studies. Multivariate analysis and linear models supported geographical location as a significant predictor for the level of most of the metals. Zn and Cu, generally and Pb, Cd, Mn, Cr at some sites exhibited potential bioaccumulation from surrounding environments. Inter-species comparisons strengthen the inference that the House crow is a reliable bioindicator species for the qualitative assessment of local urban environmental pollution and could be a useful tool for inter-regional monitoring programs.
    Matched MeSH terms: Birds
  10. Fulltext Bird species diversity in the padawan limestone area, sarawak
    Mansor MS, Sah SA, Koon LC, Rahman MA
    Trop Life Sci Res, 2011 Dec;22(2):65-80.
    PMID: 24575218 MyJurnal
    Bird surveys were conducted in the Padawan Limestone Area for seven days at each of two study sites, Giam and Danu, from August to December 2008. The purpose of the study was to compare the area's bird species richness and abundance of bird species in other limestone areas and in other forest types. The study also compared the species richness and relative abundance of birds in undisturbed and disturbed areas at both study sites. Twenty mist nets were deployed for 12 hours daily. During this study period, direct observations of birds were also made. In all, 80 species from 34 families were recorded at both sites. At Giam, 120 birds were mist-netted. These birds represented 31 species from 16 families. The direct observations at Giam recorded 13 species from 11 families. In the undisturbed area, 21 species from 13 families were mist-netted, whereas in the disturbed area, 21 species from 10 families were mist-netted. In Danu, a total of 48 birds, representing 25 species from 12 families, were mist-netted. The observations at Danu recorded 34 species from 19 families. Twelve species from 7 families were mist-netted in the undisturbed area, whereas 18 species from 11 families were mist-netted in the disturbed area. Statistical analysis showed that the species diversity index differed significantly between undisturbed and disturbed areas.
    Matched MeSH terms: Birds
  11. Fulltext Does weather play an important role in the early nesting activity of colonial waterbirds? A case study in putrajaya wetlands, malaysia
    Ismail A, Rahman F
    Trop Life Sci Res, 2013 Aug;24(1):1-7.
    PMID: 24575237 MyJurnal
    Environmental factors can play important roles in influencing waterbird communities. In particular, weather may have various biological and ecological impacts on the breeding activities of waterbirds, though most studies have investigated the effect of weather on the late stages of waterbird breeding (e.g., hatching rate, chick mortality). Conversely, the present study attempts to highlight the influence of weather on the early nesting activities of waterbirds by evaluating a recently established mixed-species colony in Putrajaya Wetlands, Malaysia. The results show that only rainfall and temperature have a significant influence on the species' nesting activities. Rainfall activity is significantly correlated with the Grey Heron's rate of establishment (rainfall: rs = 0.558, p = 0.03, n = 72) whereas both temperature and rainfall are associated with Painted Stork's nesting density (temperature: rs = 0.573, p = 0.013; rainfall: rs = -0.662, p = 0.03, n = 48). There is a possibility that variations in the rainfall and temperature provide a cue for the birds to initiate their nesting. Regardless, this paper addresses concerns on the limitations faced in the study and suggests long-term studies for confirmation.
    Matched MeSH terms: Birds
  12. Fulltext Current Status of the Milky Stork Re-introduction Programme in Malaysia and Its Challenges
    Ismail A, Rahman F
    Trop Life Sci Res, 2016 Aug;27(2):13-24.
    PMID: 27688848 MyJurnal DOI: 10.21315/tlsr2016.27.2.2
    This review discussed the current status of the Milky Stork Re-introduction Programme in Malaysia and the challenges it faced. Although it has continued for almost seven years, more challenges appeared as time elapsed mainly due to the arising conflicts between the implementation of conservation policy versus the development projects in Kuala Gula. Hence, the released population is struggling to adapt mainly due to the reduction of suitable habitat for nesting and disturbed foraging areas by the continuous anthropogenic activities. Furthermore, the lack of appropriate training among captive storks prior to being released also slows the adaptation of the birds in their new habitat. The increasing pattern of pollution in the area is also highlighted. Several suggestions were given to help improve the current re-introduction programme. These include improvements to the captive training method, improvement of the existing enclosure's condition and environment, protection of remaining mangrove forest, creation of a buffer zone to mitigate the increasing pollution level in the area, close monitoring of the released population, and maintaining continuous support and awareness among the public. Considering the ongoing anthropogenic activities that may impair the status of Kuala Gula as an important bird sanctuary, emphasis should be given to achieve sustainable development throughout the area.
    Matched MeSH terms: Birds
  13. Fulltext Avian data from Kenyir rainforest trail
    Nelson BR, David G, Mokhtar AF, Mamat MA, Rahman AJA
    Data Brief, 2018 Dec;21:2633-2637.
    PMID: 30761345 DOI: 10.1016/j.dib.2018.11.119
    This data article is constructed using avian (bird) counts from a recently identified trail in Kenyir rainforest, East Peninsular Malaysia. Avian chirps and naked eye visual were simultaneously used to locate the birds. After visual binocular and digital image inspection, identification of avian species were carried out using reference books. Data tabulation are divided by monsoon seasons and months before interpret using Shannon and Evenness indices. The highlights like feeding guilds, nativity, iconic species and statuses in the wild are presented with the data to increase its value. Within these, a total of 457 avian individuals from 36 avian family groups were recorded from which, 25 of these avian species occur as near threatened, vulnerable, endangered and critically endangered in the wild. Having these, the tabulated data becomes a calendar for seasonal availability of avian species which considers the 1.0 km trail suitable for bird watching, scientific study and ecotourism purposes.
    Matched MeSH terms: Birds
  14. Fulltext Birdsong Denoising Using Wavelets
    Priyadarshani N, Marsland S, Castro I, Punchihewa A
    PLoS One, 2016;11(1):e0146790.
    PMID: 26812391 DOI: 10.1371/journal.pone.0146790
    Automatic recording of birdsong is becoming the preferred way to monitor and quantify bird populations worldwide. Programmable recorders allow recordings to be obtained at all times of day and year for extended periods of time. Consequently, there is a critical need for robust automated birdsong recognition. One prominent obstacle to achieving this is low signal to noise ratio in unattended recordings. Field recordings are often very noisy: birdsong is only one component in a recording, which also includes noise from the environment (such as wind and rain), other animals (including insects), and human-related activities, as well as noise from the recorder itself. We describe a method of denoising using a combination of the wavelet packet decomposition and band-pass or low-pass filtering, and present experiments that demonstrate an order of magnitude improvement in noise reduction over natural noisy bird recordings.
    Matched MeSH terms: Birds
  15. Acanthocephala from Malaysian water fowl
    Sinriah B, Poopalachelvam M
    Southeast Asian J. Trop. Med. Public Health, 1980 Mar;11(1):143.
    PMID: 7403946
    Matched MeSH terms: Birds/parasitology*
  16. Isospora and not Eimeria oocysts in the crows from Klang
    Dissanaike AS, Poopalachelvam M
    Southeast Asian J. Trop. Med. Public Health, 1977 Sep;8(3):420.
    PMID: 607436
    Matched MeSH terms: Birds/parasitology
  17. Fulltext Recent advances in delivery of veterinary DNA vaccines against avian pathogens
    Jazayeri SD, Poh CL
    Vet Res, 2019 Oct 10;50(1):78.
    PMID: 31601266 DOI: 10.1186/s13567-019-0698-z
    Veterinary vaccines need to have desired characteristics, such as being effective, inexpensive, easy to administer, suitable for mass vaccination and stable under field conditions. DNA vaccines have been proposed as potential solutions for poultry diseases since they are subunit vaccines with no risk of infection or reversion to virulence. DNA vaccines can be utilized for simultaneous immunizations against multiple pathogens and are relatively easy to design and inexpensive to manufacture and store. Administration of DNA vaccines has been shown to stimulate immune responses and provide protection from challenges in different animal models. Although DNA vaccines offer advantages, setbacks including the inability to induce strong immunity, and the fact that they are not currently applicable for mass vaccination impede the use of DNA vaccines in the poultry industry. The use of either biological or physical carriers has been proposed as a solution to overcome the current delivery limitations of DNA vaccines for veterinary applications. This review presents an overview of the recent development of carriers for delivery of veterinary DNA vaccines against avian pathogens.
    Matched MeSH terms: Birds
  18. Seed dispersal and spatial pattern in tropical trees
    Seidler TG, Plotkin JB
    PLoS Biol, 2006 Oct;4(11):e344.
    PMID: 17048988
    Theories of tropical tree diversity emphasize dispersal limitation as a potential mechanism for separating species in space and reducing competitive exclusion. We compared the dispersal morphologies, fruit sizes, and spatial distributions of 561 tree species within a fully mapped, 50-hectare plot of primary tropical forest in peninsular Malaysia. We demonstrate here that the extent and scale of conspecific spatial aggregation is correlated with the mode of seed dispersal. This relationship holds for saplings as well as for mature trees. Phylogenetically independent contrasts confirm that the relationship between dispersal and spatial pattern is significant even after controlling for common ancestry among species. We found the same qualitative results for a 50-hectare tropical forest plot in Panama. Our results provide broad empirical evidence for the importance of dispersal mode in establishing the long-term community structure of tropical forests.
    Matched MeSH terms: Birds/physiology
  19. Fulltext New species of haematozoa from the avian families Campephagidae and Apodidae
    Barraclough RK, Robert V, Peirce MA
    Parasite, 2008 Jun;15(2):105-10.
    PMID: 18642502
    Leucocytozoon coracinae sp. nov. is described from the avian family Campephagidae and Hepatozoon apodis sp. nov. from the Apodidae. The distribution of these parasites within their respective families is discussed.
    Matched MeSH terms: Birds
  20. Fulltext Dual Actions of Mammalian and Piscine Gonadotropin-Inhibitory Hormones, RFamide-Related Peptides and LPXRFamide Peptides, in the Hypothalamic-Pituitary-Gonadal Axis
    Ubuka T, Parhar I
    Front Endocrinol (Lausanne), 2017;8:377.
    PMID: 29375482 DOI: 10.3389/fendo.2017.00377
    Gonadotropin-inhibitory hormone (GnIH) is a hypothalamic neuropeptide that decreases gonadotropin synthesis and release by directly acting on the gonadotrope or by decreasing the activity of gonadotropin-releasing hormone (GnRH) neurons. GnIH is also called RFamide-related peptide in mammals or LPXRFamide peptide in fishes due to its characteristic C-terminal structure. The primary receptor for GnIH is GPR147 that inhibits cAMP production in target cells. Although most of the studies in mammals, birds, and fish have shown the inhibitory action of GnIH in the hypothalamic-pituitary-gonadal (HPG) axis, several in vivo studies in mammals and many in vivo and in vitro studies in fish have shown its stimulatory action. In mouse, although the firing rate of the majority of GnRH neurons is decreased, a small population of GnRH neurons is stimulated by GnIH. In hamsters, GnIH inhibits luteinizing hormone (LH) release in the breeding season when their endogenous LH level is high but stimulates LH release in non-breeding season when their LH level is basal. Besides different effects of GnIH on the HPG axis depending on the reproductive stages in fish, higher concentration or longer duration of GnIH administration can stimulate their HPG axis. These results suggest that GnIH action in the HPG axis is modulated by sex-steroid concentration, the action of neuroestrogen synthesized by the activity of aromatase stimulated by GnIH, estrogen membrane receptor, heteromerization and internalization of GnIH, GnRH, and estrogen membrane receptors. The inhibitory and stimulatory action of GnIH in the HPG axis may have a physiological role to maintain reproductive homeostasis according to developmental and reproductive stages.
    Matched MeSH terms: Birds
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