Patterns in Avian nest predation in North-Central Nigeria: An experimental study

This study investigated the nest predator community and factors contributing to avian nest predation in the Amurum Forest Reserve and some surrounding farmlands, north-central Nigeria, May 2015. A total of 240 artificial nests were randomly and equally placed; elevated in shrubs and on ground vegetation within different habitats. Of this total, 160 nests were visited every third day (visited nests) while 80 nests were only visited on the last day of the experiment to determine their fate (unvisited nests). We tested the effect of vegetation parameters on the Daily Survival Rate (DSR) of visited nests as well as the influence of visitation on the predation probability of the two groups of nests. Overall, 69% of the artificial nests were predated and the potential predators captured on camera traps were the African Giant Pouched Rat Cricetomys gambianus, Tantalus Monkey Chlorocebus tantalus and Black Rat Rattus rattus. DSR was significantly influenced by nest position only in the rocky outcrop and savannah, although it seemed higher for the elevated nests in all the habitats. We found no significant effect of the vegetation parameters on DSR. The significantly lower predation probability recorded for visited compared to unvisited nests suggests that nest predators in the study area tend to avoid areas that are frequently visited by humans, an indication of anthropogenic impacts and anti-predation strategy. The findings of this study can enhance our understanding of potential nest predators in the study area as well as how nesting behaviour of bird species can influence predation risk. Key words: Daily Survival Rate, nest predation, model egg, camera trap, predation probabilit

Bat diversity and abundance in Omo Forest Reserve, Nigeria

Bats are yet to be incorporated in management plans in Nigeria. This is attributed to dearth in information as well as social stigma. This study was designed to determine bat species diversity, abundance and the relation of both indices to habitat structure. The survey was carried out in Omo forest reserve between May and June. Mist nets were deployed using stratified sampling method to place nets at 20 points. Netted points were set to be at least 200m apart. Total length of net averaged at 60 m, height ranged between 2-4m and set up after sunset from 1800-2300 hrs and before sunrise from 0400-0630 hrs. Sixty-four individuals were trapped belonging to 14 species in 8 genera and 6 families. Two other species were observed but not captured Eidolon helvum (Straw coloured fruit Bat) and Hypsignathus monstrosus (Hammer headed Fruit bat). Identification was based on Mammals of Nigeria and Mammals of Africa. Bat species diversity and bat abundance were higher in the forest compared to plantation but not significantly different. Bat species diversity decreased significantly as density of trees and litter cover increased while bat abundance decreased with increase in tree density but the relationship was not significant. Difference in diversity and abundance of bats is attributed to relative short distance between farmland and forest habitat types which provides easy access to bats for foraging. Habitat type and land usage influences the level of diversity and abundance of wildlife species for which bats are good indicators of habitat suitability.Keywords: Bats, diversity, Omo forest reserve, deforestation, density of tree

Large Mammals and Wetland utilization: a case study in Yankari Game Reserve Nigeria

The African plain harbours high abundance and diversity of mammals, most of which are confined to protected areas (PAs) due to anthro‐ pogenic threats (Craigie et al., 2010; Dirzo et al., 2014; Estes, 1999; Kingdon, 1997). Also, PAs face problems of hunting, logging and live‐ stock grazing, conflict of interest and poor management (Caro, 2001; Dharmaratne, Sang, &Walling, 2000; Gardner et al., 2009; Geldmann et al., 2015; Geldmann et al., 2015; Hall, Harris, Medjibe, & Ashton, 2003; Pressey, 1994; Salum, Eustace, Malata, & Mbangwa, 2017; Thuiller, 2007), consequently disrupting conservation goals, effective monitor‐ ing and understanding of habitat utilisation dynamics of mammals. Although wetlands are important habitats for sustaining animal populations, there is a widespread trend of increasing degradation of these habitats (Fynn, Chase, & Rӧder, 2014) and dearth of infor‐ mation pertaining to wetland utilisation in most PAs. While this is integral for effective conservation practice, few studies focus on this area in Africa (Arzamendia, Cassini, & Vila, 2006; Kumar, Mudappa, & Raman, 2010; Rahman et al., 2017). Here, we investigated the wet‐ land utilisation dynamics of large mammals in Yankari Game Reserve (YGR). The objective was to determine abundance, density and di‐ versity of large mammals and whether these variables were associ‐ ated with wetland size and time of da

Expression of Concern: Redox modification of cysteine residues regulates the cytokine activity of high mobility group box-1 (HMGB1) (Molecular Medicine (2012) 18 (250-259) DOI: 10.2119/molmed.2011.00389)

© The Author(s). 2020. The Editors-in-Chief would like to alert readers that this article (Yang et al. 2012) is part of an investigation being conducted by the journal following the conclusions of an institutional enquiry at the University of Liverpool with respect to the quantitative mass spectrometrygenerated results regarding acetylated and redox-modified HMGB1. Appropriate editorial action will be taken once the investigation is concluded. Huan Yang, Peter Lundbäck, Lars Ottosson, Helena Erlandsson-Harris, Emilie Venereau, Marco E. Bianchi, Yousef Al-Abed, Ulf Andersson, and Kevin J. Tracey agree to this editorial expression of concern. Daniel J. Antoine has not responded to any correspondence from the editor/publisher about this editorial expression of concern

Circannual variation in blood parasitism in a sub-Saharan migrant passerine bird, the garden warbler

Knowing the natural dynamics of pathogens in migratory birds is important, for example, to understand the factors that influence the transport of pathogens to and their transmission in new geographical areas, whereas the transmission of other pathogens might be restricted to a specific area. We studied haemosporidian blood parasites of the genera Plasmodium, Haemoproteus and Leucocytozoon in a migratory bird, the garden warbler Sylvia borin. Birds were sampled in spring, summer and early autumn at breeding grounds in Sweden, on migration at Capri, Italy and on arrival and departure from wintering staging areas in West Africa: mapping recoveries of garden warblers ringed in Fennoscandia and Capri showed that these sites are most probably on the migratory flyway of garden warblers breeding at Kvismaren. Overall, haemosporidian prevalence was 39%, involving 24 different parasite lineages. Prevalence varied significantly over the migratory cycle, with relatively high prevalence of blood parasites in the population on breeding grounds and at the onset of autumn migration, followed by marked declines in prevalence during migration both on spring and autumn passage. Importantly, we found that when examining circannual variation in the different lineages, significantly different prevalence profiles emerged both between and within genera. Our results suggest that differences in prevalence profiles are the result of either different parasite transmission strategies or coevolution between the host and the various parasite lineages. When separating parasites into common vs. rare lineages, we found that two peaks in the prevalence of rare parasites occur; on arrival at Swedish breeding grounds, and after the wintering period in Africa. Our results stress the importance of appropriate taxonomic resolution when examining host-parasite interactions, as variation in prevalence both between and within parasite genera can show markedly different patterns

Phylogeographic Patterns in Africa and High Resolution Delineation of Genetic Clades in the Lion (Panthera leo)

Comparative phylogeography of African savannah mammals shows a congruent pattern in which populations in West/Central Africa are distinct from populations in East/Southern Africa. However, for the lion, all African populations are currently classified as a single subspecies (Panthera leo leo), while the only remaining population in Asia is considered to be distinct (Panthera leo persica). This distinction is disputed both by morphological and genetic data. In this study we introduce the lion as a model for African phylogeography. Analyses of mtDNA sequences reveal six supported clades and a strongly supported ancestral dichotomy with northern populations (West Africa, Central Africa, North Africa/Asia) on one branch, and southern populations (North East Africa, East/Southern Africa and South West Africa) on the other. We review taxonomies and phylogenies of other large savannah mammals, illustrating that similar clades are found in other species. The described phylogeographic pattern is considered in relation to large scale environmental changes in Africa over the past 300,000 years, attributable to climate. Refugial areas, predicted by climate envelope models, further confirm the observed pattern. We support the revision of current lion taxonomy, as recognition of a northern and a southern subspecies is more parsimonious with the evolutionary history of the lion.Netherlands Organization for Scientific Research (NWO) (project no. 820.01.002)

How generalist are these forest specialists? What Sweden's avian indicators indicate

Monitoring of forest biodiversity and habitats is an important part of forest conservation, but due to the impossible task of monitoring all species, indicator species are frequently used. However, reliance on an incorrect indicator of valuable habitat can reduce the efficiency of conservation efforts. Birds are often used as indicators as they are charismatic, relatively easy to survey, and because we often have knowledge of their habitat and resource requirements. In the Swedish government's environmental quality goals, there are a number of bird species identified as being associated with 'older' and 'high natural value' forests. Here we evaluate the occurrence of four of these indicator species using data from 91 production forest stands and 10 forest reserves in southern Sweden. The bird species assessed are willow tit Poecile montanus, coal tit Periparus ater, European crested tit Lophophanes cristatus and Eurasian treecreeper Certhia familiaris. For the production stands assessed, these indicator species exhibited no significant preferences regarding forest composition and structure, indicating a wider range of habitat associations than expected. These species frequently showed territorial behavior in forest stands <60 and even 40 years of age; much younger than the 120-year threshold for 'older forest' as defined by governmental environmental goals. As almost 80% of the production stands >= 10 years old included at least one of the four indicator species, this raises questions regarding the suitability of these species as indictors of forests of high conservational value in southern Sweden. Notably, besides the four species assessed here, none of the additional indicator taxa identified by the government, were recorded in the 10 reserves. This outcome may reflect the difficulties involved in finding bird indicator species indicative of high natural values in this region. Our results highlight the importance of coupling bird surveys with quantified assessments of proximate vegetation cover

Cutaneous nociception and neurogenic inflammation evoked by PACAP38 and VIP

Pituitary adenylate cyclase-activating peptide-38 (PACAP38) and vasoactive intestinal peptide (VIP) belong to the same secretin–glucagon superfamily and are present in nerve fibers in dura and skin. Using a model of acute cutaneous pain we explored differences in pain perception and vasomotor responses between PACAP38 and VIP in 16 healthy volunteers in a double-blind, placebo-controlled, crossover study. All participants received intradermal injections of 200 pmol PACAP38, 200 pmol VIP and placebo into the volar forearm. Measurements included pain intensity on a visual analog scale (VAS), blood flow by laser Doppler flowmetry, visual flare and wheal. Pain intensities after PACAP38 and VIP were mild and limited to a short time of about 100 s after injection. The area under the VAS-time curve was larger following PACAP38 (P = 0.004) and VIP (P = 0.01) compared to placebo. We found no statistical difference in pain perception between PACAP38 and VIP. Skin blood flow increase, flare and wheal were larger after both PACAP38 (P = 0.011) and VIP (P = 0.001) compared to placebo. VIP induced a considerably larger increase in skin blood flow, flare and wheal than PACAP38 (P = 0.002). In conclusion, we found that peripheral nociceptive cutaneous responses elicited by PACAP38 and VIP are similar in healthy volunteers. This suggests that acute pain and vasomotor responses following intradermal injections of PACAP38 and VIP are primarily mediated by VPAC receptors

A red knot as a black swan:How a single bird shows navigational abilities during repeat crossings of the Greenland Icecap

Despite the wealth of studies on seasonal movements of birds between southern nonbreeding locations and High Arctic breeding locations, the key mechanisms of navigation during these migrations remain elusive. A flight along the shortest possible route between pairs of points on a sphere ('orthodrome') requires a bird to be able to assess its current location in relation to its migration goal and to make continuous adjustment of heading to reach that goal. Alternatively, birds may navigate along a vector with a fixed orientation ('loxodrome') based on magnetic and/or celestial compass mechanisms. Compass navigation is considered especially challenging for summer migrations in Polar regions, as continuous daylight and complexity in the geomagnetic field may complicate the use of both celestial and magnetic compasses here. We examine the possible use of orientation mechanisms during migratory flights across the Greenland Icecap. Using a novel 2 g solar-powered satellite transmitter, we documented the flight paths travelled by a female red knotCalidris canutus islandicaduring two northward and two southward migrations. The geometry of the paths suggests that red knots can migrate across the Greenland Icecap along the shortest-, orthodrome-like, path instead of the previously suggested loxodrome path. This particular bird's ability to return to locations visited in a previous year, together with its sudden course changes (which would be appropriate responses to ambient wind fields), suggest a map sense that enables red knots to determine location, so that they can tailor their route depending on local conditions

Exploring the molecular mechanisms underlying the potentiation of exogenous growth hormone on alcohol-induced fatty liver diseases in mice

<p>Abstract</p> <p>Background</p> <p>Growth hormone (GH) is an essential regulator of intrahepatic lipid metabolism by activating multiple complex hepatic signaling cascades. Here, we examined whether chronic exogenous GH administration (via gene therapy) could ameliorate liver steatosis in animal models of alcoholic fatty liver disease (AFLD) and explored the underlying molecular mechanisms.</p> <p>Methods</p> <p>Male C57BL/6J mice were fed either an alcohol or a control liquid diet with or without GH therapy for 6 weeks. Biochemical parameters, liver histology, oxidative stress markers, and serum high molecular weight (HMW) adiponectin were measured. Quantitative real-time PCR and western blotting were also conducted to determine the underlying molecular mechanism.</p> <p>Results</p> <p>Serum HMW adiponectin levels were significantly higher in the GH1-treated control group than in the control group (3.98 ± 0.71 μg/mL vs. 3.07 ± 0.55 μg/mL; <it>P </it>< 0.001). GH1 therapy reversed HMW adiponectin levels to the normal levels in the alcohol-fed group. Alcohol feeding significantly reduced hepatic adipoR2 mRNA expression compared with that in the control group (0.71 ± 0.17 vs. 1.03 ± 0.19; <it>P </it>< 0.001), which was reversed by GH therapy. GH1 therapy also significantly increased the relative mRNA (1.98 ± 0.15 vs. 0.98 ± 0.15) and protein levels of SIRT1 (2.18 ± 0.37 vs. 0.99 ± 0.17) in the alcohol-fed group compared with those in the control group (both, <it>P </it>< 0.001). The alcohol diet decreased the phosphorylated and total protein levels of hepatic AMP-activated kinase-α (AMPKα) (phosphorylated protein: 0.40 ± 0.14 vs. 1.00 ± 0.12; total protein: 0.32 ± 0.12 vs. 1.00 ± 0.14; both, <it>P </it>< 0.001) and peroxisome proliferator activated receptor-α (PPARα) (phosphorylated protein: 0.30 ± 0.09 vs. 1.00 ± 0.09; total protein: 0.27 ± 0.10 vs. 1.00 ± 0.13; both, <it>P </it>< 0.001), which were restored by GH1 therapy. GH therapy also decreased the severity of fatty liver in alcohol-fed mice.</p> <p>Conclusions</p> <p>GH therapy had positive effects on AFLD and may offer a promising approach to prevent or treat AFLD. These beneficial effects of GH on AFLD were achieved through the activation of the hepatic adiponectin-SIRT1-AMPK and PPARα-AMPK signaling systems.</p