Abomasal and plasma nitrogen constituents of steers fed on different physical forms of shelled maize

Eight abomasally fistulated steers were fed on diets of either ground, cracked or whole shelled maize at equalized intakes. Dry matter disappearance as a percentage of dietary intake averaged 73.1, 69.9 and 65.1 for steers fed ground, cracked and whole shelled maize, respectively, but these differences were not significant (P > 0.05). Total abomasal N tended to be lower in steers given cracked maize; however, this difference was nonsignificant. Abomasal nonprotein N was somewhat lower, and protein N tended to be higher with ground maize, these differences also being nonsignificant. Cracked maize resulted in slightly greater amounts of abomasal nonprotein N and lower amounts of protein N. Plasma urea-N was highest in steers fed on cracked maize. Concentrations of abomasal amino acids were not significantly (P > 0.05) affected by the form of the maize. Of the plasma amino acids, lysine and alanine were significantly higher (P < 0.05) with cracked maize and glutamic acid was significantly higher (P < 0.01) with whole shelled maize. Total essential amino acids were significantly (P < 0.05) higher with cracked maize. The ratios of glycine to the branched-chain amino acids (valine, leucine and isoleucine) in either plasma or abomasal digesta were similar for ground, cracked or whole shelled maize.     

The populations of the freshwater pearl mussel, <Emphasis Type="Italic">Margaritifera margaritifera</Emphasis> (Linnaeus, 1758), and the thick shelled river mussel, <Emphasis Type="Italic">Unio crassus</Emphasis> Philipsson, 1788, in Latvia

The populations of two endangered species—the freshwater pearl mussel Margaritifera margaritifera and the thick shelled river mussel Unio crassus in Latvia were studied. The specimens were counted, measured, population density and age structure were calculated. The possible host fish presence was found.     

Are oystercatchers (Haematopus ostralegus) selecting the most profitable mussels (Mytilus edulis)?

Size selection by oystercatchers (Haematopus ostralegus) feeding on the edible mussel Mytilus edulis by hammering the ventral side is analysed and compared with the predictions of an optimal diet model. It is found that the oystercatchers select mussels between 30 and 45 mm long which are not overgrown by barnacles and which are thin shelled. However, after including waste handling events in both the profitability and the diet model, and estimating the prey population available to the oystercatchers, a good agreement between the prediction and the data is found. These results are further discussed in the light of optimal foraging theory.     

Formation of Yolk‐Shelled Ni–Co Mixed Oxide Nanoprisms with Enhanced Electrochemical Performance for Hybrid Supercapacitors and Lithium Ion Batteries

Yolk‐shelled particles with tailored physical and chemical properties are attractive for electrochemical energy storage. Starting with metal acetate hydroxide with tetragonal prism‐like shapes, yolk‐shelled Ni–Co mixed oxide nanoprisms with tunable composition have been prepared by simple thermal annealing in air. It is found that the yolk‐shelled structure is formed due to the fast thermally driven contraction process. With the favorable porous structure and composition, these yolk‐shelled Ni–Co oxide particles manifest greatly enhanced electrochemical properties when evaluated as electrodes for both hybrid supercapacitors and lithium ion batteries. In particular, the resultant Ni_0.37Co oxide sample delivers very high specific capacitance of over 1000 F g^?1 at a current density of 10 A g^?1 with remarkably high capacitance retention of 98% after 15 000 cycles.     

Three species of Mytilus and their hybrids identified in a Scottish Loch: natives, relicts and invaders?

Three species of the mussel, Mytilus, occur in the North Atlantic region, M. edulis, M. galloprovincialis and M. trossulus, and hybrid zones are present where their distributions overlap. M. edulis is a native species in the UK. M. galloprovincialis originated in the Mediterranean and its distribution extends northwards along the Atlantic seaboard to Scotland. Baltic Sea mussels have a M. trossulus ancestry but are highly introgressed by M. edulis. In recent decades, farming of mussels on long-line rope culture systems has been introduced into Scotland. On farms in Loch Etive, a form of mussel with a fragile shell and a different shape to either M. edulis or M. galloprovincialis has been increasing in frequency over recent years. Samples of fragile shelled, normal strong shelled and intermediate mussel types were sampled from two farms in 2006 and compared with samples of M. edulis, M. galloprovincialis and M. trossulus from other sources where their species identity is well established. Abundance relative to depth, shell strength, condition index and shell morphology were analysed together with 5 allozyme loci and one nuclear DNA genetic marker (Me 15/16). The fragile shelled mussels, and many of those classed as intermediate, were identified as a mixture of M. trossulus and M. trossulus x M. edulis hybrids. This identification was strongly supported by both morphological and genetic data and is the first record of the presence of M. trossulus in UK waters. M. trossulus in Loch Etive are most likely to be a post-glacial relict population restricted to the low salinity area of the Loch that has recently increased in abundance due to commercial mussel growing activity. In addition, individual mussels of all three species and their hybrids were detected amongst Loch Etive mussels. This is the first genetic demonstration of all three species and their hybrids occurring together in one location in the Atlantic region and provides a unique opportunity to study the processes of speciation, divergence, and introgression in the genus Mytilus.     

Development and commercial use of afla-Guard®, an aflatoxin biocontrol agent

A biopesticide, afla-guard^®, has been developed for controlling aflatoxin contamination in peanuts. This product provides the means of introducing a competitive, non-aflatoxigenic strain ofAspergillus flavus into soils where peanuts are being grown. The introduced strain competitively excludes toxigenic strains naturally present from invading developing peanuts. The biocontrol technology was made commercially available in 2004 by Circle One Global, Inc., upon receiving U.S. Environmental Protection Agency section 3 registration of afla-guard^® as a biopesticide. The product was applied to approximately 2000 ha of peanuts in Georgia and Alabama during the 2004 crop year. Application of afla-guard^® changed the composition ofA. flavus soil populations from an average 71.1% toxigenic strains in untreated fields to only 4.0% in treated soils. Analyses of farmer's stock peanuts being delivered at seven different locations showed a consistent reduction in aflatoxin contamination in peanuts from fields treated with afla-guard^®. Over all locations, aflatoxin averaged 78.9 ng/g in untreated peanuts compared with 11.7 ng/g in treated peanuts, an 85.2% reduction. Peanuts from treated and untreated fields were stored together in separate warehouse bins at two different locations. Aflatoxin analyses at the Unadilla, GA location showed that 48.4% of shelled edible lots from untreated fields contained unacceptable levels of aflatoxin (>15 ng/g). At the Dawson, GA location, 15.8% of shelled lots from untreated fields contained >15 ng/g. At both locations, no shelled edible lots from treated fields contained >15 ng/g. Mean aflatoxin concentrations in edible peanuts from untreated and treated fields at Unadilla were 36.2 and 0.9 ng/g, respectively. At Dawson the respective means were 7.2 and 2.2 ng/g.     

SHELL SCARRING IN CALLIOSTOMA ZIZYPHINUM (PROSOBRANCHIA: TROCHIDAE) FROM STRANGFORD LOUGH, NORTHERN IRELAND

Pink and white shells of Calliostoma zizyphinum show both undamagedand damaged scars. White shelled individuals predominate inStrangford Lough, Northern Ireland where Calliostoma densitiesand scarring levels are high. No white shells were found intertidally,outside the entrance channel to the Lough. Significant differencesoccur in the size of Calliostoma shells between sampling sitesbut not between different colour morphs at each site. Howeverin pooled samples, pink individuals are significantly largerthan white individuals. When sites and morphs are consideredseparately, pink Calliostoma density is negatively correlatedwith water movement. At sites where pink Calliostoma occur,the percentage of pink shelled individuals is negatively correlatedwith total Calliostoma density. Damaged and undamaged scarring values per unit area of shell,show highly significant differences between sites and damagedscars are significantly higher in white individuals. Undamagedscars are not correlated with any of the environmental parametersrecorded, but are positively correlated with damaged scars suggestinga common causative factor. The level of damaged scarring ispositively correlated with crab/total Calliostoma ratio at allsites and where each colour morph was considered separately.Multiple regression analyses reveal that crab/Calliostoma ratiosaccount for 42% of the between site variation in damaged scars.Significantly higher levels of damaged scars are found at siteswith high crab densities and significantly larger individualsare found at sites where crab densities are intermediate invalue. The largest and most highly scarred individuals occur at siteswith most coarse substrata where Calliostoma are present intheir lowest densities. The higher scarring levels and smallersize of white individuals reflect either higher mortality orreduced growth in white shelled Calliostoma. (Received 25 November 1991; accepted 5 November 1992)     

Carbon dioxide production as an indicator of Aspergillus flavus colonisation and aflatoxins/cyclopiazonic acid contamination in shelled peanuts stored under different interacting abiotic factors

Aspergillus flavus is the main xerophylic species colonising stored peanuts resulting in contamination with aflatoxins (AFs) and cyclopiazonic acid (CPA). This study evaluated the relationship between storage of shelled peanuts under interacting abiotic conditions on (a) temporal respiration (R) and cumulative CO₂ production, (b) dry matter losses (DMLs) and (c) aflatoxin B₁ (AFB₁) and CPA accumulation. Both naturally contaminated peanuts and those inoculated with A. flavus were stored for 7-days under different water activities (a_w; 0.77–0.95) and temperatures (20–35°C). There was an increase in the temporal CO₂ production rates in wetter and warmer conditions, with the highest respiration at 0.95 a_w + A. flavus inoculum at 30°C (2474 mg CO₂kg⁻¹h⁻¹). The DMLs were modelled to produce contour maps of the environmental conditions resulting in maximum/minimum losses. Maximum mycotoxin contamination was always at 0.95 a_w although optimal temperatures were 25-30°C for AFs and 30-35°C for CPA. These results showed a correlation between CO₂ production and mycotoxin accumulation. They also provide valuable information for the creation of a database focused on the development of a post-harvest decision support system to determine the relative risks of contamination with these mycotoxins in stored shelled peanuts.     

Double‐Shelled NiO‐NiCo2O4 Heterostructure@Carbon Hollow Nanocages as an Efficient Sulfur Host for Advanced Lithium–Sulfur Batteries

Double‐shelled NiO‐NiCo₂O₄ heterostructure@carbon hollow nanocages as efficient sulfur hosts are synthesized to overcome the barriers of lithium–sulfur (Li–S) batteries simultaneously. The double‐shelled nanocages can prevent the diffusion of lithium polysulfides (LiPSs) effectively. NiO‐NiCo₂O₄ heterostructure is able to promote polysulfide conversion reactions. Furthermore, the thin carbon layer outside can improve the electrical conductivity during cycling. Besides, such unique double‐shelled hollow nanocage architecture can also accommodate the volumetric effect of sulfur upon cycling. As a result, the prepared S/NiO‐NiCo₂O₄@carbon (C) electrode exhibits good rate capacities and stable cycling life up to 500 cycles at 0.5 C with a very low capacity decay rate of only ≈0.059% per cycle.     

Host-size preference of the parasitoidAnisopteromalus calandrae [Hym: Pteromalidae] onSitophilus zeamais (Col.: Curculionidae) larvae with a uniform age distribution

First generationAnisopteromalus calandrae (Howard) collected from commercial stored maize in South Carolina were exposed to a mixture of all sizes of immatureSitophilus zeamais Motschulsky, representative of a uniform age distribution, in shelled maize. Eighty-seven percent of parasitism is expected on larvae with tunnel diameters of 0.9 to 1.8 mm and 6% on prepupae and pupae, given this host-size distribution. Preference was greatest for large host larvae (1.6 mm diameter), intermediate for other larvae in the range 0.9 to 1.8 mm, and least for pupae and small larvae. Host-stage preference is discussed with respect to Chesson's (1983) parameters for preference, α_i, probability of parasitism, P_i, and electivity index, ?_i.     

EVIDENCE FOR PREDATION AS A FACTOR IN DETERMINING SHELL COLOR FREQUENCIES IN A MANGROVE SNAIL LITTORINA SP. (PROSOBRANCHIA: LITTORINIDAE)

It was hypothesized that in Littorina populations living on Avicennia marina in Moreton Bay, Queensland, yellow shelled individuals are at a selective advantage over other shell colors and that this advantage is due to differential selection by predators. Yellow shelled individuals were more likely to be recaptured than others, indicating a higher survival rate of yellows. When predation was restricted on ten mangrove trees, the apparent advantage of yellow shells was removed. After 18 months, the relative frequency of yellow shelled individuals was significantly lower on experimental trees than on control trees. A combination of selection for crypsis and for the less common morph is suggested as the mechanism maintaining the high levels of variation in this species.     

Oxygen consumption and aspects of energetics in a Malaysian population of Natica maculosa Lamarck (Gastropoda) feeding on the trochacean gastropod Umbonium vestiarium (L.)

Oxygen consumption in sea water increased with size and tissue weight of Natica maculosa Lamarck at ambient temperatures (28–29.5 dgC) and salinities (31–32‰) in a fashion comparable with other naticids. When measured in submerged shore sand, oxygen consumption resembled that in sea water among smaller and some larger Natica but was much lower in several larger snails. Even using the higher measurements, respiration accounted for a remarkably low proportion of the energy consumed in Umbonium prey, and this also matches previous findings with Polinices. Limited observations indicate that production of egg collars may account for > 30‰ of the consumption in adult females. Estimation of faeces and mucus were, however, unsuccessful. It is suggested that respiration in nature might be higher than recorded hitherto because of high metabolic costs and very long duration of drilling the shelled prey.     

Mussels as ecosystem engineers: Their contribution to species richness in a rocky littoral community

Mussels are important ecosystem engineers in marine benthic systems because they aggregate into beds, thus modifying the nature and complexity of the substrate. In this study, we evaluated the contribution of mussels (Brachidontes rodriguezii, Mytilus edulis platensis, and Perna perna) to the benthic species richness of intertidal and shallow subtidal communities at Cerro Verde (Uruguay). We compared the richness of macro-benthic species between mussel-engineered patches and patches without mussels but dominated by algae or barnacles at a landscape scale (all samples), between tidal levels, and between sites distributed along a wave exposition gradient. Overall, we found a net increase in species richness in samples with mussels (35 species), in contrast to samples where mussels were naturally absent or scarce (27 species). The positive trend of the effect did not depend upon tidal level or wave exposition, but its magnitude varied between sites. Within sites, a significant positive effect was detected only at the protected site. Within the mussel-engineered patches, the richness of all macro-faunal groups (total, sessile and mobile) was positively correlated with mussel abundance. This evidence indicates that the mussel beds studied here were important in maintaining species richness at the landscape-level, and highlights that beds of shelled bivalves should not be neglected as conservation targets in marine benthic environments.     

Poles Apart: The “Bipolar” Pteropod Species Limacina helicina Is Genetically Distinct Between the Arctic and Antarctic Oceans

The shelled pteropod (sea butterfly) Limacina helicina is currently recognised as a species complex comprising two sub-species and at least five “forma”. However, at the species level it is considered to be bipolar, occurring in both the Arctic and Antarctic oceans. Due to its aragonite shell and polar distribution L. helicina is particularly vulnerable to ocean acidification. As a key indicator of the acidification process, and a major component of polar ecosystems, L. helicina has become a focus for acidification research. New observations that taxonomic groups may respond quite differently to acidification prompted us to reassess the taxonomic status of this important species. We found a 33.56% (±0.09) difference in cytochrome c oxidase subunit I (COI) gene sequences between L. helicina collected from the Arctic and Antarctic oceans. This degree of separation is sufficient for ordinal level taxonomic separation in other organisms and provides strong evidence for the Arctic and Antarctic populations of L. helicina differing at least at the species level. Recent research has highlighted substantial physiological differences between the poles for another supposedly bipolar pteropod species, Clione limacina. Given the large genetic divergence between Arctic and Antarctic L. helicina populations shown here, similarly large physiological differences may exist between the poles for the L. helicina species group. Therefore, in addition to indicating that L. helicina is in fact not bipolar, our study demonstrates the need for acidification research to take into account the possibility that the L. helicina species group may not respond in the same way to ocean acidification in Arctic and Antarctic ecosystems.     

Shell shape variation in the Nassariid Buccinanops globulosus in northern Patagonia

Morphological variation among natural populations is a phenomenon commonly observed in marine invertebrates and well studied, particularly, in shelled gastropods. The nassariid Buccinanops globulosus is interesting to study shell shape variation because it exhibits strong interpopulation differences in life history features, including maximum size, fecundity and growth rate. In this study, we examined the pattern of variation in size and shell shape among populations and between sexes of B. globulosus (Bahía San Antonio 40°29′S 63°01′W, Playa Villarino 40°45′S 64°40′W and Bahía Nueva 42°46′S 65°02′W). In particular, we used geometric morphometric techniques to test: (1) whether the two components of shell morphology (size and shape) are independent and (2) whether shape differences between sexes are consistently found among populations, regardless of their body sizes. Our results show shell shape variation between the populations of B. globulosus of northern Patagonia. Intra-specific shell shape variation is affected by body size, indicating allometry. Regardless of the size differences, individuals from Playa Villarino have high-spired shells, and shorter apertures and wider columellar area than individuals from the other populations. Also, sex-related shape differences were consistently found at each population, thus suggesting a common sexual dimorphism in shell morphology for this species. The functional significance of the variability found is discussed in terms of the flexibility of developmental programmes for morphology as well as the evolution of phenotypic plasticity.     

Fasciola hepatica in Snails Collected from Water-Dropwort Fields using PCR

Fasciola hepatica is a trematode that causes zoonosis mainly in cattle and sheep and occasionally in humans. Fascioliasis has been reported in Korea; however, determining F. hepatica infection in snails has not been done recently. Thus, using PCR, we evaluated the prevalence of F. hepatica infection in snails at 4 large water-dropwort fields. Among 349 examined snails, F. hepatica-specific internal transcribed space 1 (ITS-1) and/or ITS-2 markers were detected in 12 snails and confirmed using sequence analysis. Morphologically, 213 of 349 collected snails were dextral shelled, which is the same aperture as the lymnaeid snail, the vectorial host for F. hepatica. Among the 12 F. hepatica-infected snails, 6 were known first intermediate hosts in Korea (Lymnaea viridis and L. ollula) and the remaining 6 (Lymnaea sp.) were potentially a new first intermediate host in Korea. It has been shown that the overall prevalence of the snails contaminated with F. hepatica in water-dropwort fields was 3.4%; however, the prevalence varied among the fields. This is the first study to estimate the prevalence of F. hepatica infection using the vectorial capacity of the snails in Korea.     

Sediment resuspension dampens the effect of nutrient inputs on the phytoplankton community: a mesocosm experiment study

We sampled four populations of the robustly shelled Pleurocera canaliculata from large rivers and five pleurocerid populations bearing more fusiform shells (nominally P. acuta and P. pyrenellum) from smaller streams in a study area extending from upstate New York to northern Alabama, USA. Gene frequencies at 9 allozyme-encoding loci revealed that each population of P. acuta or P. pyrenellum was more genetically similar to the P. canaliculata population inhabiting the larger river immediately downstream than to any nominal conspecific. Thus, the extensive intraspecific variation in shell robustness displayed by these nine populations has apparently been rendered cryptic by taxonomic confusion. We then employed geometric morphometrics to explore a gradient in shell morphology from the acuta form to the typical canaliculata form in 18 historic samples collected down the length of Indiana’s Wabash River. The shell forms appeared generally distinctive on the major axes yielded by relative warp analysis (increasing robustness and decreasing spire elongation), although some overlap was apparent. MANCOVA returned a significant relationship between multivariate shape variation and stream size, as measured by drainage area. Possible drivers for this phenomenon include an environmental cline in the risk of dislodgement due to hydrodynamic drag and shifts in the community of predators.     

Spontaneous sexual differentiation of Mesocestoides corti tetrathyridia in vitro

Barrett N. J., Smyth J. D. and Ong S. J. 1982. Spontaneous sexual differentiation of Mesocestoides corti tetrathyridia in vitro. International Journal for Parasitology12: 315–322. Tetrathyridia of Mesocestoides corti, from the body cavity of mice, maintained in the laboratory by intraperitoneal infection, were used for in vitro culture. In an initial experiment, after 50 days asexual multiplication in vitro one tetrathyridium spontaneously segmented and developed into a sexually mature adult. Further experiments were carried out in an attempt to determine the conditions favouring segmentation and sexual differentiation. A combination of 5 or 10 ml liquid medium S1OE.H (basically composed of CMRL 1066 and foetal calf serum with supplements) changed every 3 days, in a Leighton tube (19 × 105 mm), rotated at 38°C and gassed with 10 or 20% CO₂, containing between 100 and 200 tetrathyridia, has proved to be most suitable so far. Numerous adult worms with normal male and female genitalia have been obtained in this system. However, segmentation is sporadic, rather than consistent and only a few shelled eggs with hooked oncospheres have so far been obtained, suggesting that impregnation and fertilization in vitro is not fully comparable with that in vivo.     

Ethnobotanical notes about some uses of medicinal plants in Alto Tirreno Cosentino area (Calabria, Southern Italy)

The present zootherapeutic study describes the traditional knowledge related to the use of different animals and animal-derived products as medicines by the Saharia tribe reside in the Shahabad and Kishanganj Panchayat Samiti's of Baran district of Rajasthan, India. A field survey was conducted from April to June 2006 by performing interview through structured questionnaire with 21 selected respondents, who provided information regarding use of animals and their products in folk medicine. A total of 15 animal species were recorded and they are used for different ethnomedical purposes, including cough, asthma, tuberculosis, paralysis, earache, herpes, weakness, muscular pain etc. The zootherapeutic knowledge was mostly based on domestic animals, but some protected species like the peacock (Pavo cristatus,), hard shelled turtle (Kachuga tentoria), sambhar (Cervus unicolor) were also mentioned as medicinal resources. We would suggest that this kind of neglected traditional knowledge should be included into the strategies of conservation and management of faunistic resources. Further studies are required for experimental validation to confirm the presence of bioactive compounds in these traditional remedies and also to emphasize more sustainable use of these resources.     

The effect of parity on morphological evolution among phrynosomatid lizards

The shift from egg laying to live‐bearing is one of the most well‐studied transitions in evolutionary biology. Few studies, however, have assessed the effect of this transition on morphological evolution. Here, we evaluated the effect of reproductive mode on the morphological evolution of 10 traits, among 108 species of phrynosomatid lizards. We assess whether the requirement for passing shelled eggs through the pelvic girdle has led to morphological constraints in oviparous species and whether long gestation times in viviparous species have led to constraints in locomotor morphology. We fit models to the data that vary both in their tempo (strength and rate of selection) and mode of evolution (Brownian or Ornstein‐Uhlenbeck) and estimates of trait optima. We found that most traits are best fit by a generalized multipeak OU model, suggesting differing trait optima for viviparous vs. oviparous species. Additionally, rates (σ²) of both pelvic girdle and forelimb trait evolution varied with parity; viviparous species had higher rates. Hindlimb traits, however, exhibited no difference in σ² between parity modes. In a functional context, our results suggest that the passage of shelled eggs constrains the morphology of the pelvic girdle, but we found no evidence of morphological constraint of the locomotor apparatus in viviparous species. Our results are consistent with recent lineage diversification analyses, leading to the conclusion that transitions to viviparity increase both lineage and morphological diversification.