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1.
Helmeted Guineafowl, Numida meleagris, populations have declined significantly within the Midlands of KwaZulu-Natal since the early 1980s. Because guineafowl have been observed feeding on harvested soybean lands and because raw soybeans are known to contain anti-nutritional factors, research into the digestibility of raw soybeans was conducted to investigate possible localized factors in suppressing populations of these birds. A digestibility study was carried out on the apparent metabolizable energy (AME) and the amino acids of both raw and processed soybeans, as well as a number of other feed ingredients, using Helmeted Guineafowl and adult roosters, Gallus gallus, as a control. The results of the energy balance studies were similar for both the guineafowl and the roosters. Soybean, both raw and processed, was found to be comparable with the other feed ingredients in terms of the digestibility of gross energy, but the amino acid digestibility of raw soybeans was considerably lower than that of processed soybean oilcake meal. The availability of raw soybean may thus only be contributing to localized dietary constraints within guineafowl populations. 相似文献
2.
We investigated the effects of agriculture and the availability of edge habitat on populations of Helmeted Guineafowl Numida meleagris and associated avian diversity and species composition in woodland and grassland biomes in the Midlands of KwaZulu-Natal province, South Africa. Study sites within woodland biome had greater species diversity than those in grassland, whereas adjacent, high-quality, protected habitat in grassland sites, enhanced diversity within this biome. Both guineafowl populations and overall avian diversity declined with increasingly intensive agriculture and disappearance of edge habitat and associated, optimally fragmented habitat mosaic. Furthermore, traditional agriculture in the form of contouring in a pesticide-free environment, resulted in extensive edge habitat that appeared to provide additional food and cover for birds. This, in turn, caused an increase in overall bird diversity, and in guineafowl populations in particular. The widespread decline in Helmeted Guineafowl populations in the Midlands that started in the 1980s, and possibly the decline in species associated with this variegated landscape, was therefore caused by the loss of the habitat mosaic to intensive, modern, monoculture, crop agriculture. Maintaining species diversity and healthy guineafowl populations within these habitats requires the persistence or re-creation of a habitat mosaic and the resulting edge habitat on a landscape scale. 相似文献
3.
Johann H van Niekerk 《Ostrich》2019,90(1):37-40
This study describes the relationship between Helmeted Guineafowl Numida meleagris and invasive alien trees on livestock and maize farms south-east of Johannesburg, Gauteng province, South Africa. The dependence of the birds on alien trees affects strategies for the removal of these trees. During June to December 2014, Helmeted Guineafowl were recorded weekly on maps along a 42 km transect. Since Helmeted Guineafowl live in cohesive social groups of 15–20 birds, they roost communally in one or two trees during winter rather than spreading across an entire tree grove. The distribution of alien trees across the landscape in patches has enabled Helmeted Guineafowl flocks to reach new feeding patches near to roosting trees, as old feeding patches are depleted. One Helmeted Guineafowl flock of 15–20 birds requires ~0.09 ha covered with mature alien trees for roosting. Suggestions are presented relating to the reduction of alien trees in compliance with the Conservation of Agricultural Resources Act 43 of 1983 and conservation of Helmeted Guineafowl. 相似文献
4.
《Ostrich》2013,84(2):153-156
Field surveys were conducted in the Krugersdorp Game Reserve, Gauteng province, South Africa, during 1978–1981 to study the habitat preferences of Helmeted Guineafowl Numida meleagris. The study area was traversed with a vehicle in the late afternoons on a set route (12 km) and at least one observation was conducted each month during the three-year period. With the aid of binoculars all guineafowl that were sighted were counted and recorded on a map. The purposes were to (1) describe the habitat preferences of guineafowl and (2) to demonstrate that weeds attracted guineafowl during winter and can be retained in modified landscapes (e.g. farms) to provide important microhabitats. The highest mean monthly density across five habitat categories throughout the year was recorded in old vegetable gardens. The old vegetable gardens of c. 35 ha attracted more than 60% of the guineafowl population from April to October, which was mainly during winter when the birds scratched actively in weedy patches. 相似文献
5.
At Namibia’s two major airports, Hosea Kutako International and Eros (domestic), 117 bird strike collision incidents were recorded between 2006 and 2010. A risk assessment, which included a proposed risk weighting methodology, was conducted at Hosea Kutako and Eros airports, which estimated the probability of an accident/collision as well as the consequence of such a collision. The assessment included surveys of bird occurrence frequencies as well as pilot interviews. The results of the risk assessments were compared with actual bird strike incidences for each species, frequency of occurrence of birds and pilot perceptions of species risk, in order to find whether risk assessment and pilot perception are reliable measures of potential bird strike incidence. White-backed Vulture Gyps africanus and Helmeted Guineafowl Numida meleagris were the highest risk species at both airports. They were also, after Crowned Lapwing Vanellus coronatus, the species most often observed by pilots. Bird strike records showed that Crowned Lapwing and Helmeted Guineafowl were also the most frequently struck birds at both airports. The study illustrates how combining risk assessment, pilot perception and bird strike history can benefit bird strike minimisation plans at airports through the rapid identification of priority bird species. 相似文献
6.
A total of 7,334 crop and/or stomach contents from 239 species of South African birds were examined for ticks. Only 36 ticks were found: 24 in 21 cattle egret (Bubulcus ibis), four in four helmeted guineafowl (Numida meleagris), one in a crowned plover (Vanellus coronatus) and seven in a single lilacbreasted roller (Coracias caudata). In most cases identification of the ticks was not possible although the genera Boophilus, Hyalomma and Rhipicephalus were represented. With the exception of the oxpeckers which were not represented in this survey, we conclude that predation by birds on ticks is uncommon in South Africa. 相似文献
7.
Through laboratory and field experiments, we investigated the effect of food availability and food nutritive value on food selection by helmeted guineafowl ( Numida meleagris galeata Pallas) during the dry season in the Waza region of North Cameroon. Field study and crop analysis shows that a wide variety of food types are eaten by guineafowl during the dry season. Analysis of 101 crops from wild birds reveals a statistically significant positive correlation between the sodium and water content of food items and the quantity found in the crops. Rhizomes of Stylochiton lancifolius and termites form the bulk of the diet of this species during the dry season. It is concluded that the selection of water‐rich food may be an adaptation to dry environment. 相似文献
8.
Alain Vignal Simon Boitard Nomie Thbault Guiguigbaza‐Kossigan Dayo Valentine Yapi‐Gnaore Issaka Youssao Abdou Karim Ccile Berthouly‐Salazar Nra Plinks‐Bodzsr Daniel Gumen Francoise Thibaud‐Nissen Wesley C. Warren Michle Tixier‐Boichard Xavier Rognon 《Molecular ecology resources》2019,19(4):997-1014
The helmeted guinea fowl Numida meleagris belongs to the order Galliformes. Its natural range includes a large part of sub‐Saharan Africa, from Senegal to Eritrea and from Chad to South Africa. Archaeozoological and artistic evidence suggest domestication of this species may have occurred about 2,000 years BP in Mali and Sudan primarily as a food resource, although villagers also benefit from its capacity to give loud alarm calls in case of danger, of its ability to consume parasites such as ticks and to hunt snakes, thus suggesting its domestication may have resulted from a commensal association process. Today, it is still farmed in Africa, mainly as a traditional village poultry, and is also bred more intensively in other countries, mainly France and Italy. The lack of available molecular genetic markers has limited the genetic studies conducted to date on guinea fowl. We present here a first‐generation whole‐genome sequence draft assembly used as a reference for a study by a Pool‐seq approach of wild and domestic populations from Europe and Africa. We show that the domestic populations share a higher genetic similarity between each other than they do to wild populations living in the same geographical area. Several genomic regions showing selection signatures putatively related to domestication or importation to Europe were detected, containing candidate genes, most notably EDNRB2, possibly explaining losses in plumage coloration phenotypes in domesticated populations. 相似文献
9.
The helmeted guineafowl, Numida meleagris , is a member of the Galliformes (King & McLelland, 1975). This order includes the domestic fowl, Callus domeslicus , which has undoubtedly dominated research studies in poultry production generally. Many of the anatomical studies in birds have been carried out using the domestic fowl, with comparatively little mention of other genera. Although the genera in the Galliformes have very many similarities, few anatomical differences have been shown to exist. For example, Crowe & Crowe (1979) have found some striking differences between the blood supply to the head and neck of the guineafowl and the domestic fowl.
The guineafowl has become a popular poultry bird in Nigeria, and has been said to rank second to the domestic fowl, despite its seasonal breeding pattern. The further improvement of this genus in our poultry production has necessitated increased studies into its nutritional requirements, management procedures and disease prevalence. In line with this improvement is the need for anatomical data on the female reproductive organs as a basis for the breeding and selection programme. The aim of this study is to describe the macroscopic arterial blood supply to the reproductive organs of the guineafowl. 相似文献
The guineafowl has become a popular poultry bird in Nigeria, and has been said to rank second to the domestic fowl, despite its seasonal breeding pattern. The further improvement of this genus in our poultry production has necessitated increased studies into its nutritional requirements, management procedures and disease prevalence. In line with this improvement is the need for anatomical data on the female reproductive organs as a basis for the breeding and selection programme. The aim of this study is to describe the macroscopic arterial blood supply to the reproductive organs of the guineafowl. 相似文献
10.
The eggshells of the cormorant (Phalacrocorax carbo), domestic fowl (Gallus domesticus), gannet (Sula bassana), guinea fowl (Numida meleagris), greater flamingo (Phoenicopterus ruber), and shag (Phalacrocorax aristotelis) have been separated into two groups on the basis of the composition of their outer stratum. In the domestic fowl, guinea fowl and greater flamingo the outer stratum is an organic cuticle while in the sea-birds it is an inorganic cover rich in vaterite. The calcareous deposits on the membranes of eggs of the domestic fowl which are shell-less at oviposition have been shown to consist essentially of the vaterite form of calcium carbonate. Reasons for the occurrence of this polymorph of calcium carbonate are discussed with relation to the physiology of the birds. 相似文献
11.
We have characterized a deletion in the MC1R gene causing the loss of one amino acid (p.Phe256del), which is perfectly associated with melanism in guinea fowl (Numida meleagris). Co‐segregation of the p.Phe256del with melanism was confirmed in 25 offspring born from a cross of two heterozygote birds; therefore we suggest that this mutation is responsible for the black phenotype. Interestingly, this is the first case of recessive melanism linked to MC1R. 相似文献
12.
Ecological studies traditionally assume that generalist populations are homogeneous in the use of food resources, but empirical evidence supports that intraspecific differences in morphology, physiology and behaviour affect foraging decisions and promote diet variation among individuals. Furthermore, the temporal availability of resources may shape the dynamics of population trophic niche, which ultimately depends on individual niches. In this study, we investigated the seasonal changes in individual-based networks between the Helmeted Manakin Antilophia galeata, a generalist frugivorous bird, and fruiting plants, following theoretical models of interindividual diet variation based on the Optimal Diet Theory. Selective individuals were the majority of the generalist population of the Helmeted Manakin. Our results suggest that the structure of the individual-resource networks varied seasonally. We found that modularity was higher than expected by chance in the wet season, when fruit availability was also higher. In the dry season, modules disappeared and the network became more nested. These findings are consistent with the Distinct Preference Model of diet variation. We suggest that downscaling ecological networks to the individual level may reveal emergent properties that, albeit existent, are not evident in species–resources networks. 相似文献
13.
Stephen M. Gatesy 《Journal of morphology》1999,240(2):115-125
Avian striding bipedalism was studied in the helmeted guineafowl, Numida meleagris. High‐speed cineradiographs, light films, and videos were used to record hind limb movements across a wide range of speeds. In particular, direct visualization of the skeleton in X‐ray images allowed changes in pelvic and femoral position to be quantified with great accuracy for the first time. With the exception of limb protraction angle, all stride parameters are speed‐dependent. During the stance phase, guineafowl primarily employ knee flexion at very low speeds. At higher speeds, the magnitudes of hip and knee extension in the second half of stance progressively increase. Pelvic rotations are relatively small, but birds gradually pitch further forward with speed. An aerial phase is not present at speeds less than 2.0 m/sec, but discontinuities in the relationship of some parameters to speed indicate a gait transition near 0.9 m/sec. Birds are considered to be flying theropod dinosaurs, making characterization of bipedalism in living birds essential to understanding the evolution of theropod locomotion. Data from guineafowl, including the kinematic effects of speed, are informative about several aspects of locomotion in extinct theropods. However, many details of avian bipedalism evolved only within a subset of Theropoda, and are therefore not directly applicable to all members of the clade. J. Morphol. 240:115–125, 1999. © 1999 Wiley‐Liss, Inc. 相似文献
14.
We describe the occurrence of D. galeata×longispina hybrids in two lakes of western Norway. Parental species and interspecific hybrids were characterised by both nuclear and mitochondrial molecular markers. In one of the populations, hybrids were shown to dominate the population over several years. A few individuals in both populations were probably not F1 hybrids, but possibly backcrosses or F2 hybrids. Most (possibly all) F1 hybrids were of D. galeata maternal origin. In addition, interspecific hybrids could be identified based on morphological characters, which were intermediate between the parental species. Interspecific hybridisation between these two species is remarkable, since they are distantly related. 相似文献
15.
- 1 Taxonomic issues in many Daphnia species complexes are often confused by a high degree of phenotypic plasticity and by interspecific hybridisation. Here, we employ molecular genetic tools to confirm the species composition and incidence of hybridisation in extant and resting egg populations of Daphnia from Windermere and Esthwaite Water in the English Lake District.
- 2 A combination of species‐diagnostic allozymes and mtDNA, confirms that contemporary populations are dominated by a single species, D. galeata.
- 3 We present the first account of genetic characterisation of dated ‘resting’ eggs using microsatellites and mtDNA, employing PCR‐based DNA recovery, thus providing a temporal dimension to taxonomic patterns. Thirty years ago, two species were present in Esthwaite, D. galeata and D. hyalina, but Windermere populations were dominated by D. galeata only.
- 4 The use of PCR‐based mtDNA RFLP analysis as a species‐diagnostic tool, and microsatellites to monitor clonal diversity, provide a valuable approach for long‐term studies, especially in populations free from the complicating effect of frequent hybridisation. The detailed limnological records available for many large lakes, and associated changes in land‐use, pollutants and climate, combined with long‐term ephippial molecular genetic data, provide opportunities for exploring natural and anthropogenic impacts on genetic and community structure.
16.
This research investigates the economic and social aspects of human–wildlife conflict (HWC) in Mhokwe, Mbire district, Zimbabwe. Data were collected through key informant interviews and a questionnaire survey. Most households in Mhokwe rely on crop and livestock production, and hence, HWC is an important factor affecting livelihoods. More than 60% of respondents experienced problems with lions (Panthera leo Linnaeus), spotted hyaenas (Crocuta crocuta Erxleben), armoured bush crickets (Acanthoplus speiseri Brancsik) and quelea birds (Quelea quelea Reichenbach). Other problem animals included elephant (Loxodonta africana Blumenbach), vervet monkey (Chlorocebus pygerythrus Cuvier), kudu (Tragelaphus strepsiceros Pallas), chacma baboon (Papio ursinus Kerr), bushpig (Potamochoerus porcus Linnaeus) and common duiker (Sylvicapra grimmia Linnaeus). Few incidences of conflicts were reported for hippopotamus (Hippopotamus amphibius Linnaeus), side-striped jackal (Canis adustus Sundevall), porcupine (Hystrix africaeaustralis Peters), nile crocodile (Crocodylus niloticus Laurenti), African wild cat (Felis lybica Forster), African python (Python sebae Gmelin) and guinea fowl (Numida meleagris Linnaeus). Livestock and crop losses were US$45,285 and US$57,541 in 2013 and 2014, respectively. Despite the losses, most respondents had positive attitudes towards wildlife. Construction of strong kraals and implementation of integrated pest management (IPM) can contribute to conflict reduction. 相似文献
17.
Presently, wildcatFelis silvestris silvestris Schreber, 1777 populations are fragmented and rapidly declining in most of Europe. Although habitat destruction possibly
constitutes the most serious threat to wildcat survival, hybridisation with feral domestic cats is also a critical problem.
However, the mechanisms that allow domestic cats to colonise former wild cat home ranges are yet unclear. The present paper
describes the decrease of typical phenotypic wildcats and the increase of phenotypic domestic cats in a remote wild area of
Portugal (Serra da Malcata). A field survey using box-traps and radio-tracking between 1998 and 2001 revealed that wildcats
were widespread in the study area and no domestic cats were present. A second survey using camera traps between 2005 and 2007
revealed only one wildcat whereas four typical domestic phenotype individuals were photographed. The present study clearly
emphasizes the need for urgent measures aimed at preserving wildcat populations. These measures should include a national
census of the species and an extensive monitoring of genetic integrity of wildcat populations, followed by the elaboration
of a wildcat conservation action plan. 相似文献
18.
J. M. Winterbottom 《Ostrich》2013,84(4):182-204
Keffen, R. H. &; Jarvis, M. J. F. 1984. Some measurements relating to Ostrich eggs. Ostrich 55:182-187. Eggs from wild Zimbabwean Ostriches Struthio camelus australis and domesticated South African hybrid birds, were compared. Formulae were tested to determine their accuracy when used to calculate egg weights, surface area and density. Calculated values were compared with some actual measurements. The main motivation for the study was the need to calculate fresh egg weights of wild Ostriches, as an aid to determining weight loss during incubation under natural conditions. Eggs from wild birds were, on average, smaller than those from domesticated birds, even though the wild adults were larger than domesticated birds. However, newly batched chicks from hybrid eggs weighed less than those from wild eggs. 相似文献
19.
Qi Liu Daogui Deng Kun Zhang Ping He Yuchen Sun Tingting Zhang Wei Yang Wei Liu 《Ecology and evolution》2019,9(22):12688-12700
Mitochondrial 16S rDNA and CO I gene were used as molecular markers for the analysis of the genetic diversity and differentiation of Daphnia galeata populations in nine water bodies in the middle and lower reaches of the Yangtze River. In the combined 16S rDNA and CO I gene sequences, 54 variable sites and 44 haplotypes were observed among 219 individuals belonging to nine D. galeata populations. Average haplotype diversity and nucleotide diversity were, respectively, 0.72% and 0.56%. The F‐statistics (FST) value of the D. galeata populations was 0.149. According to the results of the neutral test, D. galeata in the middle and lower reaches of the Yangtze River had experienced a bottleneck effect in the history. Molecular variance analysis indicated that the genetic differentiation of the D. galeata populations mainly occurred within populations (85.09%). Greater genetic differentiations of D. galeata among individuals within populations appeared in the populations from the Huaihe River basin, whereas smaller genetic differentiations occurred in the populations from the middle reaches of the Yangtze River. Strong gene flows were all observed between Group I (four populations from the middle reaches of the Yangtze River) and Group ΙΙ (three populations from the middle and lower reaches of the Yangtze River), and Group ΙΙΙ (two populations from the Huaihe River basin). The effective migration rates (M) were 851.49 from Group I to Group ΙΙ and 685.96 from Group I to Group ΙΙΙ, respectively. However, no significant relationship was observed between the genetic differentiation and geographical distance of the nine populations (r = .137, p > .05). Results suggested that the genetic differentiation of D. galeata in the water bodies in the middle and lower reaches of the Yangtze River resulted mainly from geographical isolation. 相似文献
20.
Occupancy models (Ecology, 2002; 83: 2248) were developed to infer the probability that a species under investigation occupies a site. Bayesian analysis of these models can be undertaken using statistical packages such as WinBUGS, OpenBUGS, JAGS, and more recently Stan, however, since these packages were not developed specifically to fit occupancy models, one often experiences long run times when undertaking an analysis. Bayesian spatial single‐season occupancy models can also be fit using the R package stocc. The approach assumes that the detection and occupancy regression effects are modeled using probit link functions. The use of the logistic link function, however, is algebraically more tractable and allows one to easily interpret the coefficient effects of an estimated model by using odds ratios, which is not easily done for a probit link function for models that do not include spatial random effects. We develop a Gibbs sampler to obtain posterior samples from the posterior distribution of the parameters of various occupancy models (nonspatial and spatial) when logit link functions are used to model the regression effects of the detection and occupancy processes. We apply our methods to data extracted from the 2nd Southern African Bird Atlas Project to produce a species distribution map of the Cape weaver (Ploceus capensis) and helmeted guineafowl (Numida meleagris) for South Africa. We found that the Gibbs sampling algorithm developed produces posterior samples that are identical to those obtained when using JAGS and Stan and that in certain cases the posterior chains mix much faster than those obtained when using JAGS, stocc, and Stan. Our algorithms are implemented in the R package, Rcppocc. The software is freely available and stored on GitHub ( https://github.com/AllanClark/Rcppocc ). 相似文献