A new look for TWS publications

The appearance of The Wildlife Society (TWS) publications (i.e., Journal of Wildlife Management [JWM], Wildlife Monographs [WM], Wildlife Society Bulletin [WSB]) has changed over the years. In 2021, a new journal design (NJD) will be implemented for TWS publications following months of discussion with Council and the journal editors. The scope of the articles and the mission of the journals will not change, but the format and layouts will be modified to simplify typesetting, assist with online reading, and provide a contemporary look for the publications of TWS.     

Morphological and biochemical approaches to assess the nutritional condition of the Argentine hake Merluccius hubbsi larvae from two different nursery areas

The Argentine hake, Merluccius hubbsi, is one of the most important fishing species in the Argentine Sea due to its great abundance and high-quality meat. The study of the nutritional condition is widely used to determine the physiological state of the fish larvae and to estimate their survival possibilities. The larval nutritional condition reflects the environmental conditions to which they have been exposed and represents a useful instrument to determine favourable nursery areas. It also provides tools for the comprehensive management of a population subjected to fishing exploitation. This study aimed to determine potential differences in the nutritional condition of M. hubbsi larvae from the two fishing stocks (Northern and Southern) of the species. The authors assessed the nutritional condition of larvae captured during the 2012 main reproductive peak in the nursery areas of each population. Two different methodologies were applied: a morphometrical approach, by recording five morphometric variables, and a biochemical technique, employing the RNA/DNA index (RD_s) and its derived index of growth performance. The morphometrical indexes did not show differences in the larval condition between both stocks. Nonetheless, the RD_s index did detect differences in the nutritional condition of larvae from different stocks. The RD_s index of larvae in pre-flexion and flexion stages showed significant differences between stocks, indicating that these stages are more susceptible to starvation. The results suggest that the biochemical indexes prove to be more sensitive than the morphometric indexes to detect slight differences in hake larvae nutritional condition. The scope and limitations of these techniques for the analysis of the nutritional condition of larvae are discussed.     

Fecal Nitrogen Concentration as a Nutritional Quality Indicator for European Rabbit Ecological Studies

Measuring the quality of the nutritional resources available to wild herbivores is critical to understanding trophic regulation processes. However, the direct assessment of dietary nutritional characteristics is usually difficult, which hampers monitoring nutritional constraints in natural populations. The feeding ecology of ruminant herbivores has been often assessed by analyzing fecal nitrogen (FN) concentrations, although this method has been less evaluated in other taxa. This study analyzed the suitability of FN as an indicator of ingesta quality in the European rabbit (Oryctolagus cuniculus), which is a keystone lagomorph species in Mediterranean ecosystems and of great conservation interest. Firstly, domestic O. cuniculus were used to evaluate under experimental conditions the accuracy of total FN and the metabolic FN as diet quality indicators of forages with characteristics similar to those available under natural conditions. Secondly, the accuracy of Near-Infrared Spectroscopy (NIRS) to calculate FN was tested using partial least squares regression. Thirdly, a pilot field study was conducted to monitor FN dynamics from wild O. cuniculus in three different habitats during wet and drought periods. A strong association was found between diet type and total FN and metabolic FN (Pseudo-R² ≥ 0.89). It was also found that NIRS calibrations were accurate for depicting nitrogen concentrations (R² > 0.98 between NIRS and chemical results). Finally, the seasonal FN dynamics measured in the field were consistent with current knowledge on vegetation dynamics and forage limitations in the three habitats. The results support the use of NIRS methods and FN indices as a reliable and affordable approach to monitoring the nutritional quality of rabbit habitats. Potential applications include the assessment of the mechanistic relationships between resource limitations and population abundance, e.g., in relation to natural drought cycles and to habitat interventions aimed at reinforcing rabbit populations.     

Silicon reduces herbivore performance via different mechanisms,depending on host–plant species

There is mounting evidence silicon (Si) can alter plant nutrient dynamics and is an important functional trait in plant defence and plant–insect ecology. Despite this, there remains a paucity in our understanding of how Si‐driven changes in nutritional quality can impact herbivore performance across different plant species. We investigated how Si alters plant nutritional quality and the concomitant effects on the performance of the Australian native generalist herbivore Helicoverpa punctigera feeding on three economically significant plant species of varying Si‐uptake ability: Brassica napus (non‐Si accumulator), Cucumis sativus (intermediate Si accumulator) and Sorghum bicolor (high Si accumulator). Si supplementation reduced the nutritional quality of B. napus but increased phosphorus concentrations in S. bicolor. Si reduced herbivore performance in all host–plant species, which correlated directly with Si concentrations in Si‐accumulating host plants C. sativus and S. bicolor. However, on B. napus, Si affected herbivore performance indirectly by reducing nutritional quality (foliar carbon:nitrogen ratio and phosphorus concentration). This suggests Si availability can affect herbivore performance directly via Si concentration on Si‐accumulating hosts, and indirectly via nutritional quality in a non‐Si accumulator. The resistance‐enhancing effects of Si on multiple species offer opportunity for agriculture to utilise this abundant element in sustainable management practices.     

Relationships among catalpol sequestration,metabolism and nutritional efficiencies of the catalpa sphinx,Ceratomia catalpae (Lepidoptera: Sphingidae)

Sequestration of defensive compounds acquired from the environment can be costly to herbivorous insects. The catalpa sphinx, Ceratomia catalpae Boisduval (Lepidoptera: Sphingidae) sequesters the iridoid glycoside catalpol, which it acquires from Catalpa spp. (Lamiales: Bignoniaceae) host plants, at concentrations above those in host plant leaves. Previous research has shown that C. catalpae larvae are avoided by predatory arthropods; however, catalpol sequestration is negatively associated with the larval immune response, suggesting a cost to sequestration. By measuring the mass of C. catalpae larvae, their frass, and their diet, as well as respiration rate and catalpol sequestration, this study aimed to determine whether sequestration is also associated with reduced growth and nutritional efficiency. I found that respiration rate was negatively correlated with the amount of catalpol sequestered and positively correlated with the concentration, or proportion dry mass of catalpol sequestered, and that the amount of catalpol sequestered was positively correlated with three of four measures of nutritional efficiency. Larger larvae that were closer to pupation sequestered very low proportions dry mass of catalpol and had a reduced respiratory rate per unit mass. These results suggest that sequestration has some costs for expenditure of energy, but is positively correlated with several growth and nutrition‐related processes. Instead, the immunological cost of sequestration measured in previous studies could be due to direct effects on immune system components. Further research on the potential metabolic costs of chemical defense in other specialist species is recommended.     

Chromosome Banding and 18S rDNA in situ Hybridization Analysis of Seven Species of the Family Achiridae (Teleostei: Pleuronectiformes)

Achiridae is an important family of the order Pleuronectiformes widely distributed in North, Central, and South America with freshwater and marine species. In the present study cytogenetic analyses comprising conventional and molecular techniques were carried out in seven species of this family. The following diploid numbers (2n) and fundamental numbers (FN) were obtained: Achirus declivis 2n = 34, FN = 52; Achirus lineatus 2n = 40, FN = 66; Catathyridium jenynsi 2n = 40 and FN = 50; Gymnachirus nudus 2n = 36 and FN = 50; Hypoclinemus mentalis 2n = 38 and FN = 54; Trinectes paulistanus 2n = 42 and FN = 52; and Trinectes sp. 2n = 38 and FN = 54. All species presented a single nucleolar organizer region (NOR) bearing chromosome pair and C-band positive segments mainly distributed at the pericentromeric position. The wide variation observed in chromosome number and FN suggests the occurrence of larger chromosome rearrangements in the family Achiridae if compared with other families of the same order.     

Arsenate phytoextraction abilities of one-year-old tree species and its effects on the nutritional element content in plant organs

Abstract

The aim of the study was to evaluate the As phytoextraction potential of four tree species: Acer pseudoplatanus L., Betula pendula Roth., Quercus robur L., and Ulmus laevis Pall. in light of their prospective use in the phytoremediation of arsenate [As(V)] contaminated soils. The content of nutritional elements: B, Ca, K, Mg, Na, Si, P, and S was also analyzed. The trees were grown for 1?month in hydroponic cultures (Knop medium) supplemented with As(V), (1?mM). The results showed that the highest As accumulation efficiency was characterized by B. pendula (BCF = 0.87) and Q. robur (BCF = 0.5). Betula pendula accumulated about 80% of As in its roots (TF = 0.22) whereas Q. robur accumulated more than 60% of As in its shoots (TF = 1.60). The other tree species accumulated significantly lower amounts of As, more than 60% of which collected in their shoots. As(V) phytoextraction led to a significantly lower level of P and S in the roots of all tested tree species. Betula pendula seems promising for phytostabilisation and Q. robur for phytoextraction of As(V) from contaminated soils. The obtained results confirm the accumulation and translocation of As(V), as well as the acquisition of nutritional elements by the selected tree species.     

Food and feeding preferences of Himalayan gray goral (Naemorhedus goral bedfordi) in Pakistan and Azad Jammu and Kashmir

Himalayan gray goral is endemic to Himalayas and Hindukush ranges. Analysis of 15 fecal samples and field observations from different areas of Pakistan and Azad Kashmir suggest that goral consumes foliage of a minimum of 28 plant species. Trees, shrubs and grasses appear in the ratio of 1:36:63 and hence the species is a grazer, though may opt for browsing when forced. The species mainly subsists on six species of grasses (Chrysopogon aucheri=17.97%, Themeda anathera=13.03%, Poa pratensis=11.23%, Digitaria decumbens=9.30%, Apluda mutica=7.51%, Aristida cyanatha=3.15%), though leaves of shrubs (Myrsine africana=11.38%, Daphne oleoides=8.87%, Carissa opaca=5.94%, Dodonaea viscose=4.79%, Rubus ellipticus=2.93%, Gymnosporia royleana=1.29%) are also consumed. Food preference indices (consumed/availability) suggest that grasses are highly preferred (16.86 times of availability), followed by shrubs (3.3 times of availability), whereas trees and herbs are not preferred. Food plants contain water (77.9±0.56%), ash (8.6±0.38%), sugars (6.8±0.16%), proteins (5.6%±0.28%) and fats (1.3±0.08%). Food provides 4,440 kcal of energy and 5.45 L of water/day/adult goral, which is sufficient to meet the requirements of the species. Grasses need to be ensured in the protected area separated for management of goral population. Zoo Biol 27:371–380, 2008. © 2008 Wiley‐Liss, Inc.     

Phylogenetic assessment of culture collection strains of Thiobacillus thioparus, and definitive 16S rRNA gene sequences for T. thioparus, T. denitrificans, and Halothiobacillus neapolitanus

The 16S rRNA gene sequences of 12 strains of Thiobacillus thioparus held by different culture collections have been compared. A definitive sequence for the reference type strain (Starkey; ATCC 8158^T) was obtained. The sequences for four examples of the Starkey type strain were essentially identical, confirming their sustained identity after passage through different laboratories. One strain (NCIMB 8454) was reassigned as a strain of Halothiobacillus neapolitanus, and a second (NCIMB 8349) was a species of Thermithiobacillus. These two strains have been renamed in their catalog by the National Collection of Industrial and Marine Bacteria. The 16S rRNA gene sequence of the type strain of Halothiobacillus neapolitanus (NCIMB 8539^T) was determined and used to confirm the identity of other culture collection strains of this species. The reference sequences for the type strains of Thiobacillus thioparus and Halothiobacillus neapolitanus have been added to the online List of Prokaryotic Names with Standing in Nomenclature. Comparison of the 16S rRNA gene sequences available for strains of Thiobacillus denitrificans indicated that the sequence for the type strain (NCIMB 9548^T) should always be used as the reference sequence for new and existing isolates.     

Foods,macronutrients and fibre in the diet of blue sheep (Psuedois nayaur) in the Annapurna Conservation Area of Nepal

Food resources are often critical regulating factors affecting individual fitness and population densities. In the Himalayan Mountains, Bharal “blue sheep” (Pseudois nayaur) are the main food resource for the endangered snow leopard (Panthera uncia), as well as being preyed upon by other predators. Blue sheep, however, may face a number of challenges including food resource competition with other wild and domestic ungulates, and hunting pressure. Here, we characterized the diet of blue sheep in the Annapurna Conservation Area (ACA) of Nepal and conducted proximate nutritional analysis on a limited number of plants identified as foods. Furthermore, we investigated the macronutrient and fiber balance of these plants using nutritional geometry which is a state‐space approach to modeling multidimensional and interactive nutritional aspects of foraging. A total of 19 plant species/genera were identified in blue sheep pellets using microhistological analysis. On average, across seasons and regions of the study area, the two most frequently occurring plants in pellets were graminoids: Kobressia sp. and Carex spp. The macronutrient balance of Kobresia sp. was relatively high in carbohydrate and low in protein, while other plants in the diet were generally higher in protein and lipid content. Analysis of fiber balance showed that the two most consumed plants of blue sheep (i.e., Kobresia spp. and Carex spp.) contained the highest concentration of hemicellulose, which is likely digestible by blue sheep. The hemicellulose and lignin balance of plants ranged relatively widely, yet their cellulose contents showed less variation. Foraging by blue sheep may therefore be a balance between consuming highly digestible high‐carbohydrate plants and plants less‐digestible but higher in protein and/or lipid.     

Assessment of nutritional subsidies to freshwater mussels using a multiple natural abundance isotope approach

相似文献   

Prognostic value of prognostic nutritional index and systemic immune-inflammation index in patients with osteosarcoma

The aim of this study was to evaluate the relationship between prognostic nutritional index (PNI) and systemic immune-inflammation index (SII) and clinical features and prognosis of osteosarcoma patients. We retrospectively investigated 126 patients with surgery for osteosarcoma between 2012 and 2018 at our hospital. The preoperative PNI was calculated as albumin level (g/L) + 5 × total lymphocyte count (10 ⁹/L). The SII was defined as platelet × neutrophil/lymphocyte counts. The optimal cut-off values for PNI and SII were evaluated with receiver operating curve analysis. Clinical features and PNI and SII were tested with the χ ² test. The effects of PNI and SII on overall survival (OS) was investigated by Kaplan–Meier method and Cox proportional hazards model. A low preoperative PNI was remarkably correlated with tumor size, Enneking stage, pathological fracture, local recurrence, metastasis, and neoadjuvant chemotherapy ( p < 0.05). Whereas, a high SII was significantly associated with tumor size, histological type, Enneking stage, and neoadjuvant chemotherapy ( p < 0.05). There was a significant negative relationship between the PNI and SII ( r = 0.384; p < 0.001). For univariate analyses, the results revealed that tumor size, local recurrence, metastasis, PNI, and SII were predictors of OS ( p < 0.05). In multivariate analyses, local recurrence ( p = 0.010), metastasis ( p < 0.001), PNI ( p < 0.001), and SII ( p = 0.029) as independent prognostic factors were significantly correlated with OS. This study suggested that PNI and SII could be important prognostic parameters for patients with osteosarcoma.     

Food and specific macronutrient limitation in an assemblage of predatory beetles

Habitats vary in food resources with carnivores often being prey limited, but it is unclear whether habitats facilitate a nutritionally balanced diet. Two paradigms in nutritional ecology, ecological stoichiometry and nutritional geometry, predict that carnivores are limited mainly by protein or lipid, respectively. Using the carabid beetle Anchomenus dorsalis and 10 other predatory beetles from agricultural fields, we developed and tested two simple procedures for quantifying macronutrient‐specific habitat conditions without requiring information about the natural prey. Both procedures assume that predators forage for nutrients rather than specific prey. Our results show that 10 of 11 species were food limited. Five species were lipid limited and one species was protein limited in the field. Co‐existing predator species showed considerable segregation of fundamental macronutritional niches. A linear relationship between specific nutrient limitation and the target lipid:protein (L:P) intake ratio indicates that species with high L:P target are more protein limited while species with low L:P target are more lipid limited. The study illustrates how species within a natural assemblage vary in nutritional niche and in specific nutrient limitation.     

Phenotypic plasticity of Brevicoryne brassicae in responses to nutritional quality of two related host plants

Abstract 1. The host species used by a herbivorous insect may impose different selective pressures promoting host race formation, yet the presence of plasticity can potentially constrain host race formation. 2. The goal of this study is to determine if there is phenotypic plasticity in life history traits of Brevicoryne brassicae in response to host and nutritional quality of two host species, Brassica oleraceae and Brassica campestris, and to what extent there are genetic differences among genotypes in plasticity. 3. Plants of B. oleraceae and B. campestris were fertilised with three different nitrogen doses (with nutritive solutions of 50, 200 and 400 ppm of soluble nitrogen) to produce plants with different nutritional qualities. Eight clones of B. brassicae were reared on those plants, and days to reproduction (DTR), number of nymphs, and fitness (r_m) were recorded. 4. A significant genotype × host interaction was detected in days to reproduction. Genotype × nitrogen interaction (plasticity) was detected in the number of nymphs when aphids were raised on B. campestris. Aphids showed plasticity in DTR and marginal plasticity in r_m in reaction to the varying nitrogen content of B. oleraceae. 5. The phenotypic plasticity to fine‐scale variation of host (nutritional quality) documented here may be an important source of phenotypic variation and may potentially constrain host race formation.     

Silicon: An indigestible marker for measuring food consumption and utilization by insects

Silicon (Si) is a useful indigestible marker in plants for measuring food consumption and nutritional indices. Si concentrations in HF:HCl extracts of small (5–20 mg) samples may be measured easily using atomic emission spectroscopy. The Si marker and gravimetric methods were compared usingLymantria dispar (L.) larvae fed artificial diet with 2.5% silica (SiO₂). Both methods produced equivalent measures of consumption and nutritional indices. The Si marker method was also used to measure the consumption of six grass species by larvae ofParatrytone melane Edwards. The results were similar overall when compared with estimates of consumption based on total fecal weight, but varied significantly for some grass species. The Si marker method may be a useful alternative to the gravimetric method, especially in field situations.     

Consistent pollen nutritional intake drives bumble bee (Bombus impatiens) colony growth and reproduction across different habitats

Foraging behavior is a critical adaptation by insects to obtain appropriate nutrients from the environment for development and fitness. Bumble bees (Bombus spp.) form annual colonies which must rapidly increase their worker populations to support rearing reproductive individuals before the end of the season. Therefore, colony growth and reproduction should be dependent on the quality and quantity of pollen resources in the surrounding landscape. Our previous research found that B. impatiens foraging preferences to different plant species were shaped by pollen protein:lipid nutritional ratios (P:L), with foragers preferring pollen species with a ~5:1 P:L ratio. In this study, we placed B. impatiens colonies in three different habitats (forest, forest edge, and valley) to determine whether pollen nutritional quality collected by the colonies differed between areas that may differ in resource abundance and diversity. We found that habitat did not influence the collected pollen nutritional quality, with colonies in all three habitats collecting pollen averaging a 4:1 P:L ratio. Furthermore, there was no difference in the nutritional quality of the pollen collected by colonies that successfully reared reproductives and those that did not. We found however, that “nutritional intake,” calculated as the colony‐level intake rate of nutrient quantities (protein, lipid, and sugar), was strongly related to colony growth and reproductive output. Therefore, we conclude that B. impatiens colony performance is a function of the abundance of nutritionally appropriate floral resources in the surrounding landscape. Because we did not comprehensively evaluate the nutrition provided by the plant communities in each habitat, it remains to be determined how B. impatiens polylectic foraging strategies helps them select among the available pollen nutritional landscape in a variety of plant communities to obtain a balance of key macronutrients.     

New Ctenomys karyotypes (Rodentia,Octodontidae) from north-eastern Argentina and from Paraguay confirm the extreme chromosomal multiformity of the genus

Bone-marrow karyotypes of 68 specimens of the subterranean octodontid rodent genus Ctenomys from 16 different populations of north east Argentina and one from Paraguay have been studied. A surprising variety of chromosome numbers was found, ranging from 2n=42 to 2n=70. Some of the karyomorphs are clearly assigned to named species by topotypy: C. conoveris 2n=50, FN=56; C. argentinus, 2n=44, FN=54; C. perrensi, 2n=50, FN=84; C. dorbignyi, 2n=70, FN=84; C. roigi, 2n=48, FN=80; C. yolandae, 2n=50, FN=78. Four populations of Corrientes Province similar in morphology to C. perrensi were found to be polymorphic and polytypic; they maintain the same FN=84, but diploid numbers increase from 2n=54 to 2n=58 from SW to the NE, thus suggesting Robertsonian rearrangements. In the middle of this cline, a stable karyomorph of 2n=62, FN=84 was found in two different populations, suggesting to belong to an undescribed species. Another karyomorph of 2n=42, FN=76 found in Curuzú Laurel, Corrientes, may also prove to represent another undescribed species. One karyomorph of 2n=52, FN=74, and another of 2n=56, FN=78 from Paraná and Ubajaý (Entre Ríos Province, Argentina) respectively are close to C. rionegrensis. The relationships among these karyomorphs is considered in light of data on sperm morphology. The hypothesis is advanced that karyotypic rearrangements among the FN=84 group may be the result of Robertsonian repatterning from a 2n=70 original widespread form. Fixation of chromosomal variants is correlated with patchy distribution and small size of unstable demes, and may or may not have resulted in reproductive isolation.     

Cafeteria-style feeding trials provide new insights into the diet and nutritional strategies of the black snub-nosed monkey (Rhinopithecus strykeri): Implications for conservation

Anthropogenic changes and fragmentation of natural habitats often exert a negative effect on resource availability and distribution, and the nutritional ecology and feeding behavior of nonhuman primates. The goals of this study are to examine food choice and to identify the nutritional profile of foods consumed by the Critically Endangered black snub-nosed monkey (Rhinopithecus strykeri). To accomplish our study goals, we presented cafeteria-style feeding trials of fresh food items collected in the home range of wild black snub-nosed monkeys to the only two captive R. strykeri, and compared the nutritional profiles of the leafy foods (buds, young, and mature leaves, 100 items from 70 plant species) selected with those avoided (54 items from 48 plant species). Overall, the results indicate that captive R. strykeri selected foods that were higher in moisture (Mo; 77.7%), crude protein (CP; 21.2%), total nonstructural carbohydrates (TNC; 34.9%), and phosphorus (P; 0.37%) while tending to avoid foods with a neutral detergent fiber (NDF) content of greater than 46.8%. Leaves collected in autumn and selected by the monkeys were characterized by a slightly higher amount of metabolizable energy (ME) than those rejected (1,350 kJ/100 g vs. 1,268 kJ/100 g). In contrast, the protein content of foods collected and consumed during the spring was greater (22.9%) than in autumn (16.4%). Random Forests modeling, an ensemble learning method, indicated that the proportion of Mo, NDF, ME, CP, P, and TNC were among the most important factors in predicting which items were consumed by the captive R. strykeri during spring and autumn. On the basis of the nutritional profile of foods consumed across the two seasons, we identified 18 nutrient-rich native plant species that we recommend for use in ex- and in-situ conservation management and reforestation programs to provide long-term access to a nutritionally adequate diet.     

Electrophoretic characterization of species of fibronectin bearing sequences from the N-terminal heparin-binding domain in synovial fluid samples from patients with osteoarthritis and rheumatoid arthritis

Fragments of fibronectin (FN) corresponding to the N-terminal heparin-binding domain have been observed to promote catabolic chondrocytic gene expression and chondrolysis. We therefore characterized FN species that include sequences from this domain in samples of arthritic synovial fluid using one-and two-dimensional (1D and 2D) Western blot analysis. We detected similar assortments of species, ranging from ~47 to greater than 200 kDa, in samples obtained from patients with osteoarthritis (n = 9) versus rheumatoid arthritis (n = 10). One of the predominant forms, with an apparent molecular weight of ~170 kDa, typically resolved in 2D electrophoresis into a cluster of subspecies. These exhibited reduced binding to gelatin in comparison with a more prevalent species of ~200+ kDa and were also recognized by a monoclonal antibody to the central cell-binding domain (CBD). When considered together with our previous analyses of synovial fluid FN species containing the alternatively spliced EIIIA segment, these observations indicate that the ~170-kDa species includes sequences from four FN domains that have previously, in isolation, been observed to promote catabolic responses by chondrocytes in vitro: the N-terminal heparin-binding domain, the gelatin-binding domain, the central CBD, and the EIIIA segment. The ~170-kDa N-terminal species of FN may therefore be both a participant in joint destructive processes and a biomarker with which to gauge activity of the arthritic process.