The responses of ground-dwelling birds to heat and cold stress encompass a variety of behavioural,physiological and even morphological mechanisms.However,the role of glabrous skin in this respect has been marginally a...The responses of ground-dwelling birds to heat and cold stress encompass a variety of behavioural,physiological and even morphological mechanisms.However,the role of glabrous skin in this respect has been marginally addressed so far.The Helmeted Guineafowl(Numida meleagris)is a landfowl distributed across Sub-Saharan Africa with eight traditionally recognised extant subspecies.Among the most prominent morphological traits underlying intraspecific variability are size and pigmentation of the bare throat skin(or sack),which might be related to the different habitats and environmental conditions across its wide range.In order to explore the Helmeted Guineafowl range-wide sack variation and pigmentation in relation to thermoregulation and sexual signalling,we collected morphometric and environmental information for N.m.coronata integrating field data with the inspection of photographic material encompassing seven subspecies and environmental information from their habitats.Field data evidenced that sack size was significantly correlated with ambient temperature,thus pointing to a likely involvement of the throat sack in thermoregulation.When the pictorial data from all subspecies were pooled,sack size correlated negatively with biomass,rainfall and humidity,while a positive correlation was found with annual solar irradiation.Sack size correlated positively with monthly temperature variation among the bluethroated subspecies from southern Africa as opposed to the black-throated subspecies ranging north to Zambia and Mozambique.Still,in this latter group the sack was often larger during winter months,possibly to maximise solar radiation absorbance.Noteworthy,sack size was related to sex dimorphism in two subspecies.Sack morphology and colour in the Helmeted Guineafowl likely modulate body temperature by evaporative cooling or heating upon needs,but in some subspecies it is also seemingly related to sexual signalling.Additional studies are needed to fully understand the multifunctionality of this important morphological feature in this species.展开更多
Objective: To determine the gastrointestinal tract helminthic fauna in domestic and wild guineafowl in Zambia.Methods: Post-mortem and laboratory parasitological examinations for helminth identification and enumeratio...Objective: To determine the gastrointestinal tract helminthic fauna in domestic and wild guineafowl in Zambia.Methods: Post-mortem and laboratory parasitological examinations for helminth identification and enumeration were conducted on 198 guineafowls(148 domestic and 50 wild) from November 2010 to October 2011.Results: All guineafowls were infested with one or more helminths. Eleven helminth species, namely, Raillietina echinobothrida, Raillietina tetragona, Raillietina cesticillus, Ascaridia galli, Allodapa suctoria, Gongylonema ingluvicola, Tetrameres spp., Heterakis spp., Acuaria spiralis, Syngamus trachea, and Streptocara pectinifera were identified with no trematodes recorded. Mean nematode burden between domestic and wild fowl showed no differences having 113.7 [confidence interval(CI) 98.9-128.6] and 108(CI 76.6-139.5) nematodes respectively. In contrast, female guineafowls had a mean of 151.9(CI 128.4-177.8) nematodes per host which was significantly more than the males that had a mean of 79.6(CI 66.8-94.4). However, there were differences in helminth species richness between domestic and wild guineafowls with domestic guineafowls having more species present at a mean of 4.2(CI 3.91-4.44) than the wild ones at a mean of 3.4(CI 2.92-3.88) but there were no sex differences. Eight of the eleven helminth species co-occurred in domestic and wild fowl and five of the helminth species had higher prevalence in domestic guineafowls.Conclusions: Syngamus trachea, Streptocara pectinifera and Acuaria spiralis are reported for the first time in domestic poultry in Zambia. This study represents the first comparative study of helminths in domestic and wild guineafowls at an interface area and adds to the knowledge base in a discipline where a dearth currently exists.展开更多
Background:Understanding geographic distributions of species is a crucial step in spatial planning for biodiversity conservation, particularly as regards changes in response to global climate change.This information i...Background:Understanding geographic distributions of species is a crucial step in spatial planning for biodiversity conservation, particularly as regards changes in response to global climate change.This information is especially important for species of global conservation concern that are susceptible to the effects of habitat loss and climate change. In this study, we used ecological niche modeling to assess the current and future geographic distributional potential of White.breasted Guineafowl (Agelastes meleagrides)(Vulnerable) across West Africa. Methods:We used primary occurrence data obtained from the Global Biodiversity Information Facility and national parks in Liberia and Sierra Leone, and two independent environmental datasets (Moderate Resolution Imaging Spectroradiometer normalized difference vegetation index at 250 m spatial resolution, and Worldclim climate data at 2.5' spatial resolution for two representative concentration pathway emissions scenarios and 27 general circulation models for 2050) to build ecological niche models in Maxent. Results: From the projections, White.breasted Guineafowl showed a broader potential distribution across the region compared to the current IUCN range estimate for the species. Suitable areas were concentrated in the Gola rainforests in northwestern Liberia and southeastern Sierra Leone, the Tai.Sapo corridor in southeastern Liberia and southwestern Cote d'lvoire, and the Nimba Mountains in northern Liberia, southeastern Guinea, and northwestern Cote d'lvoire.Future climate.driven projections anticipated minimal range shifts in response to climate change. Conclusions: By combining remotely sensed data and climatic data, our results suggest that forest cover, rather than climate is the major driver of the species' current distribution. Thus, conservation efforts should prioritize forest protection and mitigation of other anthropogenic threats (e.g.hunting pressure) affecting the species.展开更多
基金funded by a research grant from the Percy Fitzpatrick Institute of African Ornithology,University of Cape Town,South Africa[REF.B 717]Partial support was provided by the Portuguese Foundation for Science and Technology[FCT fellowships PTDC/BAA-AGR/28866/2017 and CEECIND/04084/2017]the Spanish Government,Ministry of Universities(“María Zambrano”–Next Generation EU)。
文摘The responses of ground-dwelling birds to heat and cold stress encompass a variety of behavioural,physiological and even morphological mechanisms.However,the role of glabrous skin in this respect has been marginally addressed so far.The Helmeted Guineafowl(Numida meleagris)is a landfowl distributed across Sub-Saharan Africa with eight traditionally recognised extant subspecies.Among the most prominent morphological traits underlying intraspecific variability are size and pigmentation of the bare throat skin(or sack),which might be related to the different habitats and environmental conditions across its wide range.In order to explore the Helmeted Guineafowl range-wide sack variation and pigmentation in relation to thermoregulation and sexual signalling,we collected morphometric and environmental information for N.m.coronata integrating field data with the inspection of photographic material encompassing seven subspecies and environmental information from their habitats.Field data evidenced that sack size was significantly correlated with ambient temperature,thus pointing to a likely involvement of the throat sack in thermoregulation.When the pictorial data from all subspecies were pooled,sack size correlated negatively with biomass,rainfall and humidity,while a positive correlation was found with annual solar irradiation.Sack size correlated positively with monthly temperature variation among the bluethroated subspecies from southern Africa as opposed to the black-throated subspecies ranging north to Zambia and Mozambique.Still,in this latter group the sack was often larger during winter months,possibly to maximise solar radiation absorbance.Noteworthy,sack size was related to sex dimorphism in two subspecies.Sack morphology and colour in the Helmeted Guineafowl likely modulate body temperature by evaporative cooling or heating upon needs,but in some subspecies it is also seemingly related to sexual signalling.Additional studies are needed to fully understand the multifunctionality of this important morphological feature in this species.
基金Supported by the University of Zambia under UNZA-MAN No:07193
文摘Objective: To determine the gastrointestinal tract helminthic fauna in domestic and wild guineafowl in Zambia.Methods: Post-mortem and laboratory parasitological examinations for helminth identification and enumeration were conducted on 198 guineafowls(148 domestic and 50 wild) from November 2010 to October 2011.Results: All guineafowls were infested with one or more helminths. Eleven helminth species, namely, Raillietina echinobothrida, Raillietina tetragona, Raillietina cesticillus, Ascaridia galli, Allodapa suctoria, Gongylonema ingluvicola, Tetrameres spp., Heterakis spp., Acuaria spiralis, Syngamus trachea, and Streptocara pectinifera were identified with no trematodes recorded. Mean nematode burden between domestic and wild fowl showed no differences having 113.7 [confidence interval(CI) 98.9-128.6] and 108(CI 76.6-139.5) nematodes respectively. In contrast, female guineafowls had a mean of 151.9(CI 128.4-177.8) nematodes per host which was significantly more than the males that had a mean of 79.6(CI 66.8-94.4). However, there were differences in helminth species richness between domestic and wild guineafowls with domestic guineafowls having more species present at a mean of 4.2(CI 3.91-4.44) than the wild ones at a mean of 3.4(CI 2.92-3.88) but there were no sex differences. Eight of the eleven helminth species co-occurred in domestic and wild fowl and five of the helminth species had higher prevalence in domestic guineafowls.Conclusions: Syngamus trachea, Streptocara pectinifera and Acuaria spiralis are reported for the first time in domestic poultry in Zambia. This study represents the first comparative study of helminths in domestic and wild guineafowls at an interface area and adds to the knowledge base in a discipline where a dearth currently exists.
基金supported by Conservation International through a Global Environment Facility-funded Grant No.GEF-5810.
文摘Background:Understanding geographic distributions of species is a crucial step in spatial planning for biodiversity conservation, particularly as regards changes in response to global climate change.This information is especially important for species of global conservation concern that are susceptible to the effects of habitat loss and climate change. In this study, we used ecological niche modeling to assess the current and future geographic distributional potential of White.breasted Guineafowl (Agelastes meleagrides)(Vulnerable) across West Africa. Methods:We used primary occurrence data obtained from the Global Biodiversity Information Facility and national parks in Liberia and Sierra Leone, and two independent environmental datasets (Moderate Resolution Imaging Spectroradiometer normalized difference vegetation index at 250 m spatial resolution, and Worldclim climate data at 2.5' spatial resolution for two representative concentration pathway emissions scenarios and 27 general circulation models for 2050) to build ecological niche models in Maxent. Results: From the projections, White.breasted Guineafowl showed a broader potential distribution across the region compared to the current IUCN range estimate for the species. Suitable areas were concentrated in the Gola rainforests in northwestern Liberia and southeastern Sierra Leone, the Tai.Sapo corridor in southeastern Liberia and southwestern Cote d'lvoire, and the Nimba Mountains in northern Liberia, southeastern Guinea, and northwestern Cote d'lvoire.Future climate.driven projections anticipated minimal range shifts in response to climate change. Conclusions: By combining remotely sensed data and climatic data, our results suggest that forest cover, rather than climate is the major driver of the species' current distribution. Thus, conservation efforts should prioritize forest protection and mitigation of other anthropogenic threats (e.g.hunting pressure) affecting the species.