bluuebunny/crossref_metadata_2025_split huggingface dataset:
Endogenous flow of amino acids in the avian ileum as influenced by increasing dietary peptide concentrations
Authors: Ravindran Velmurugu , Morel Patrick C. H. , Rutherfurd Shane M. , Thomas Donald V. 
Published: July 2008

The aim of the present study was to establish whether feeding broiler chickens with diets containing increasing dietary peptide concentrations would cause increases in ileal endogenous amino acid flow. The flow of N and most amino acids increased quadratically (P < 0·05 to 0·001) with increasing dietary concentrations of peptides. The exceptions were the flow of threonine, serine, glycine, tyrosine and cystine, which increased linearly (P < 0·001) with dietary peptide levels. Another notable exception to the general trend was the flow of proline, which was significantly higher (P < 0·01) in birds fed the protein-free diet. The amino acid profile of endogenous protein, expressed as proportion of crude protein, indicated that the ratios of threonine, glutamic acid, proline, glycine, leucine, histidine, arginine and cystine were influenced (P < 0·05) with increasing dietary peptide concentrations. In general, compared with the protein-free diet, the ratios of threonine and arginine in endogenous protein were lower (P < 0·05) and those of glutamic acid, glycine and histidine were greater (P < 0·05) in diets with high concentrations of peptides. The ratio of proline was found to decrease (P < 0·05) with increasing dietary peptide concentrations. These changes in the amino acid profile of endogenous protein are probably reflective of changes in the output of one or more of the components of endogenous protein. Overall, the present results demonstrated that increasing dietary peptide concentrations increased the flow of endogenous amino acid flow at the terminal ileum of broiler chickens in a dose-dependent manner and also caused changes in the composition of endogenous protein. The observed changes in endogenous amino flow will influence the maintenance requirements for amino acids and also have implications for the calculation of true digestibility coefficient of feedstuffs.
Survey of subterranean termites (Isoptera: Rhinotermitidae) in a managed silvicultural plantation in Portugal, using a line-intersection method (LIS)
Authors: Nobre T. , Nunes L. , Bignell D.E. 
Published: July 2008

AbstractSubterranean termites (Reticulitermes grassei) were surveyed over successive seasons in a managed eucalyptus plantation in southeastern Portugal for 26 months. Termite activity in seven diameter categories of lying dead wood was investigated by a modified line intersection method (LIS). Each item sampled was inspected and assessed for termite attack and for general (i.e. fungal) decay status using standard protocols. Line intersection is quantitative to the extent that it can link foraging and decay parameters to woody biovolume. It was found that termites selected items with larger diameter, the observed trend showing an exponential character with greater termite attack as diameter increased. Attack by termites was positively associated with prior decay by fungi. A clear positive relationship was shown between rainfall and total woody biovolume containing live termites, underlining the importance of moisture for termite activity. Subterranean termites appeared to be important wood decomposers in the woodland studied, with an average of 30% of lying dead wood branches showing signs of termite attack.
The impact of modern farming practices on soil fertility and quality in England and Wales
Authors: WEBB J. , LOVELAND P. J. , CHAMBERS B. J. , MITCHELL R. , GARWOOD T. 
Published: July 2008

Data are presented on the effects of modern farming practices on soil as an agricultural resource in England and Wales (E&W), namely: nutrient status, pH, soil organic carbon (SOC), heavy metal concentrations, and on soil erosion risk. Fertilizer-N inputs to tillage (arable) and grassland soils increased from 84 and 65 kg/ha N in 1969 to 151 and 120 kg/ha N, respectively, in 1997. The estimated N surplus (inputs less outputs) increased from 84 and 96 kg/ha N to 102 and 154 kg/ha N, respectively, over the same time. Phosphorus inputs to tillage (mean 37 kg/ha P) and grassland (mean 21 kg/ha P) changed little over the period. However, P surpluses decreased from 25 kg/ha P in 1969 to 15 kg/ha P in 1997 on tillage land (largely as a result of greater P offtakes), and from 20 to 17 kg/ha P in 1997 on grassland (largely because of a small decrease in fertilizer P). The cumulative tillage land soil P surplus was c. 580 kg/ha P, and was estimated to increase topsoil total P concentrations by c. 170 mg/kg P and Olsen-extractable soil P by c. 26 mg/l P. The mean annual P surplus for grassland was 18 kg/ha P which, over the study period, added c. 427 kg/ha P to the soil, an increase in topsoil total P of c. 214 mg/kg P, and in Olsen-extractable P of 19 mg/l P.Concentrations of SOC in some soils have decreased between 1980 and 1995, especially where soils have been ploughed out of grassland and on lowland organic and peaty soils in tillage. The mean SOC of soils in arable/ley cultivation in 1980 was 3·4% and 2·8% in 1995.The proportion of arable soils with pH < 6·0 decreased from 10% in 1969–73 to 4% in 1990–93, reflecting the better targeting of lime inputs. In contrast, the proportion of grassland soils with pH < 6·0 increased from 39% in 1969–73 to 56% in 1990–93.Although there were statistically significant changes in the mean soil concentrations of Cd, Cu, Ni, Pb and Zn between 1980 and 1995, many of the changes were small in absolute terms. Hence, there was little evidence of marked or systematic changes in topsoil total heavy metal concentrations that could not be explained by factors other than increased pollutant loadings.Over the next 50 years or so, the threat from soil erosion to crop productivity will be greatest on shallow soils ([les ] c. 0·3 m depth), mostly over chalk and sandstone as further removal of soil will lead to increased drought stress. Provided that nutrient supplies are maintained, the evidence is that losses in arable crops on eroded soils would range between 2% and 8% of current yields.Thus, within the limitations of the data available, both in time and space, we found little evidence that most soils in E&W cannot continue to support modern farming practices, and the associated crop and animal outputs, given appropriate inputs of nutrients and an adequate degree of crop protection.
Effect of dietary condensed tannins on gastrointestinal nematodes
Authors: BUTTER N. L. , DAWSON J. M. , WAKELIN D. , BUTTERY P. J. 
Published: July 2008

It has been previously shown in this laboratory that feeding a model condensed tannin, quebracho tannin, reduces the small intestinal nematode burden in sheep and rats. The aim of the current programme was to determine whether this occurs through direct toxicity against the parasites. Both in vivo and in vitro studies were conducted. The first study compared the effect of dietary quebracho tannin (40 g/kg) on the establishment of the parasitic nematodes Nippostrongylus brasiliensis and Trichinella spiralis in the rat small intestine. The burden of N. brasiliensis, which, although closely associated with the mucosa, actually dwells within the small intestinal lumen, was significantly reduced (P<0·001) by dietary quebracho tannin. In contrast, T. spiralis, which penetrates into the small intestinal mucosa, was unaffected (>0·05) by the dietary inclusion of quebracho tannin. The second study involved monitoring the survival of adult N. brasiliensis and T. spiralis when incubated in vitro in varying concentrations of quebracho tannin in Hanks’ balanced salt solution. The survival of N. brasiliensis was compromised at concentrations as low as 0·01% (w/v) quebracho tannin but improved with the addition of 0·1% (w/v) polyethylene glycol, which binds to, and inactivates, tannin. T. spiralis was similarly affected, but much more rapidly. These results suggest that dietary quebracho tannin may reduce nematode worm burdens through a toxic effect that requires direct contact between parasite and tannin. This raises the possibility that feeding locally available plant material containing condensed tannins may be an alternative method for controlling parasite infections, especially in areas such as the tropics and subtropics.
Field activities and blood profile of pregnant South African indigenous goats after receiving dihydroxy pyridone-degrading rumen bacteria and grazing Leucaena leucocephala-grass or natural pastures
Authors: AKINGBADE A. A. , NSAHLAI I. V. , MORRIS C. D. , IJI P. A. 
Published: July 2008

Twenty-four multiparous female South African indigenous goats were used. Once a week during the 2nd (weeks 8, 11 and 14) and 3rd (weeks 18, 19 and 20) trimesters, between 08·00 and 15·00 h, four females per treatment were randomly selected and observed every 1 min for time spent grazing, browsing, ruminating and idling. Blood samples were taken once a week during the 2nd (weeks 8, 11 and 14) and 3rd (weeks 18, 19, 20 and 21) trimesters for measurements of some mineral elements and protein metabolites. Goats on natural pasture (NP) grazed 54·8 min (P<0·001) more and browsed 53 min (P<0·001) less than goats on Leucaena leucocephala-grass pasture (LGP) during the 2nd trimester. During the 3rd trimester, goats on NP treatments grazed and idled more (24·7 min, P = 0·004; 15·8 min, P = 0·044, respectively) but ruminated less (−24·1 min, P<0·001) than LGP goats. Time allotted to each field activity by the goats on both treatments within trimester seemed to be dependent on forage species composition while activity between trimesters was possibly influenced by seasons, plant type, herbage quantity, environment and quality, and changes in stage of gestation of the goats. Blood Mg level on NP was higher (P = 0·051) than on LGP during the 2nd trimester while blood Cu and albumin contents on LGP were significantly higher (P = 0·029 and 0·022, respectively) than on NP during the 3rd trimester. Furthermore, blood concentrations of the haematological parameters (except serum protein) on both treatments were within the normal range for goats in the tropics and subtropics and perhaps explain the absence of mineral and nutrient deficiency symptoms. The absence of visible symptoms of mineral deficiency and mimosine toxicity in LGP goats can be attributed to the transfer of DHP-degrading rumen bacteria. The bacteria effectively detoxified mimosine and its metabolites, thereby overcoming chelating tendency of mimosine and its metabolites. Mimosine-susceptible pregnant SAIG can be safely grazed on LGP once their rumen is completely colonized by the DHP-degrading rumen bacteria (Synergistes jonesii).
The effects of seed rate and row spacing on light interception, dry matter accumulation and seed yield, in non-dwarf and dwarf genotypes of autumn-sown determinate white lupins (Lupinus albus) in north-west Europe
Authors: SHIELD I. F. , SCOTT T. , HUYGHE C. , BRUNEAU M. , PARISSEAUX B. , PAPINEAU J. , HARZIC N. , STEVENSON H. J. , LEACH J. E. 
Published: July 2008

Two non-dwarf and two dwarf, autumn-sown determinate genotypes of white lupin (Lupinus albus L.) were sown at three sites in north-west Europe in the crop years, 1995–96, 1996–97 and 1997–98. Fully factorial experimental designs were used to analyse all combinations of genotype, seed rate and row spacing. Canopy expansion, expressed as the percentage of Photosynthetically Active Radiation (PAR) intercepted, and above ground dry matter (DM) accumulation were measured at frequent intervals during the main growing season at Rothamsted in the UK and Lusignan in France. The data from Rothamsted were used to derive models for the two processes, which were compared to the data from Lusignan, France.Crops with more than 23 plants/m2, 25 main stem leaves per plant or 1400 leaves/m2 were able to intercept more than 80% of the incident PAR. There were small differences in canopy expansion between genotypes. The non-dwarf genotypes began expansion slightly earlier (100–150 °Cd or thermal time in °Cdays, base temperature = 3 °C) than the dwarf genotypes. Crops sown on rows wider than 40 cm apart or with low plant densities (less than 23 plants/m2) were also slower to expand the canopy and intercept the PAR.The maximum quantity of dry matter accumulated by a genotype in the season (476–1044 g/m2) was related by a conversion efficiency (e) to the cumulative quantity of PAR intercepted. Values of e were generally in the range 0·92–1·65 g DM/MJ PAR during the early part of the growing season, which was comparable with other work on temperate-zone grain legumes. The non-dwarf genotype Ludet achieved an unusually large value of e (3·13 g DM/MJ PAR) and accumulated 1355 g DM/m2 at Lusignan in 1998. Late season drought in 1995–96 at Rothamsted produced some low values of e (0·75 and 0·88 g DM/MJ PAR).The seed yield was not related to the quantity of dry matter accumulated as harvest index varied from 22·3% to 49·7%. Maximum seed yield (4·54 t/ha) was produced from a low plant density (15·9 plants/m2). Mutual shading, caused by any combination of high plant densities, large numbers of leaves per plant or sowing on wide rows (>40 cm; at high plant densities within the rows) appeared to limit seed yield potential.
Effect of short transport during di-oestrus and pro-oestrus on cortisol levels and oestrous behaviour of sheep
Authors: ORIHUELA AGUSTÍN , SÁNCHEZ-MEJORADA HÉCTOR , TOLEDO MARTÍN 
Published: July 2008

Two experiments were conducted to evaluate the effect of short transport stress on ewes during di-oestrus and pro-oestrus. In Experiment 1, intra-vaginal sponges containing fluorogestone acetate were inserted into ewes for a period of 12 days. A gonadotrophin (PMSG) injection was given at the time of sponge withdrawal to induce oestrous. To dissociate the possible effect of PMSG during pro-oestrus, a second experiment was designed in which prostaglandin was used as the oestrous induction factor. Ewes in both experiments were subjected to 30 min of transport by truck. In addition, oestrous behaviour and serum cortisol concentration were evaluated. Control groups consisted of un-transported ewes. In both experiments, cortisol concentration was greater (P <0·01) in transported than in un-transported animals. No difference (P> 0·05) was found between moving the ewes during pro-oestrous or di-oestrus (0·30±0·03 v. 0·53±0·18 ng/ml and 3·88±0·97 v. 2·94±0·73 ng/ml in Experiment 1 and 2 respectively). The number of ewes detected in oestrous was similar (P>0·05) among those stressed during di-oestrus, pro-oestrus or un-transported animals within each experiment (66, 47 and 42% respectively in Experiment 1 and 96·7 in all situations in Experiment 2). In general, higher cortisol concentration and more ewes displaying oestrous behaviour were detected in Experiment 2. It was concluded that under the conditions of these experiments, no difference was found in the proportion of ewes displaying oestrus regardless of the phase of the oestrous cycle in which they were transported.
Organism responses to habitat fragmentation in two shallow-water brackish environments: the Goro Lagoon (Adriatic Sea) and the Padrongiano Delta (Tyrrhenian Sea)
Authors: Munari Cristina 
Published: July 2008

Habitat fragmentation from natural or human-mediated causes is a common phenomenon in terrestrial and aquatic environments. In this study, the effects of varying the size of habitat patches on the abundance of benthic invertebrates inhabiting date mussel (Musculista senhousia) patches was studied at two different transition environments, the Goro Lagoon (Adriatic Sea) and the Padrongiano Delta (Tyrrhenian Sea). Benthic fauna responded to habitat patchiness in a complex manner that varied according to habitat type, taxon and animal body size (small: 0.5–2.0 mm; large >2 mm). Small invertebrates were mostly polychaetes, nemertea, amphipods and isopods. Large invertebrates were mostly large polychaetes, bivalves, gastropods and crabs. Invertebrate population size and diversity seemed to be maximized in landscapes that include both small and large patches of mussel beds ‘embedded’ in a continuous matrix. Musculista senhousia patches served as a critical refuge and foraging habitat for many species. Patchy and continuous areas may promote the persistence of organisms with different life histories, especially in environments like those studied where mussel patches represent the only structural refuge available.
Trophic ecology of the octocoral Carijoa riisei from littoral of Pernambuco, Brazil. I. Composition and spatio-temporal variation of the diet
Authors: Lira Ana K.F. , Naud Jean-Philippe , Gomes Paula B. , Santos Andre M. , Perez Carlos D. 
Published: July 2008

Octocorals are common components of sublittoral benthic communities in temperate, tropical and polar areas. However, their natural diets and feeding rates are poorly known. The aim of this study was to determine qualitatively–quantitatively the diet of the octocoral Carijoa riisei (snowflake coral) and analyse the distribution and diet composition throughout a whole year at two different depths of the same environment. Hence, 30 colonies were haphazardly sampled for gastric content analysis from 2 and 6 m deep (surface and bottom) at Porto de Galinhas beach, Pernambuco, Brazil, in January, June and October 2006, and March 2007. Relative and absolute abundance, richness and occurrence frequency per gastric cavity were assessed. Shannon–Wiener index (H′) and evenness were also calculated. Items were classified according to the occurrence frequency. The biovolume of preys was estimated from meristic data, and from the biovolume were then estimated wet weight, dry weight and organic carbon. Weighed biovolume (WBV), which relates biomass and abundance, was assessed to estimate the real contribution of preys to octocoral diet. Results attested the presence of 102 phytoplankton and 25 zooplankton taxa. Mean prey size was 112.7 µm. Diatoms showed the greater richness with 88 morphotypes. Only cyanophytes and diatoms, from phytoplankton, were very common (>70%). As a whole, phytoplankton was also the most abundant group (83%), followed by crustacean fragments (5%). Thus, although having low biovolume (<0.09 mm3×10−3), the phytoplankton showed the highest WBV (44.5%). Feeding items richness was homogeneous throughout the study year and in both depths, while abundance showed significant seasonal and bathymetric fluctuation. The t-test (Hutchinson) found significant differences for prey item diversity related to depth and season. From the analysis, it is possible to conclude that the C. riisei population of the Brazilian north-eastern coast is polyphagous, but shows preference for phytoplanktonic elements and small prey. Therefore, the species behaves as a passive suspensivorous feeder with equitable biomass contribution from phytoplankton and zooplankton.
Feeding habits of the seahorse Hippocampus patagonicus in San Antonio Bay (Patagonia, Argentina)
Authors: Storero Lorena P. , González Raúl A. 
Published: July 2008

The aim of this study was to evaluate the dietary composition of the Patagonian seahorse Hippocampus patagonicus in San Antonio Bay, Patagonia, Argentina. To this end, analyses of stomach and gut contents were carried out and the diet composition was compared to the potential preys available in the natural environment. Samples were collected from different places in San Antonio Bay, a Marine Protected Area in San Matías Gulf. Type and number of prey present in the digestive tracts were registered and frequency of occurrence (%FO) and number of prey (%N) were calculated for each study area. Amphipods (Gammaridae, Caprellidae and Hiperidae) and decapods are the main dietary items of H. patagonicus in San Antonio Bay. There were differences in %FO and %N at different sites, which could indicate differences in abundance and availability of prey in the environment. No dietary differences were detected between sex and size of seahorse (ANOVA, P > 0.05). Results from the present study show that, in nature and probably due to limiting environmental factors, H. patagonicus behaves as an opportunistic predator, which preys on the most abundant and vulnerable species present in the environment.
The use and abuse of dogs on Scott's and Amundsen's South Pole expeditions
Authors: Murray Carl 
Published: July 2008

ABSTRACTIn the century since Roald Amundsen and Robert F. Scott led the first and second expeditions to reach the South Pole, commentators have frequently passed judgement on the different means of transport that the two explorers employed. In hindsight, and since he ‘won,’ they have consistently praised Amundsen for using dogs exclusively and criticised Scott for not doing the same. Surprisingly, however, almost no attention has been given to the experience of Amundsen's dogs, whose extreme suffering seems to have vanished into a collective blind spot. Here, with the aim of restoring balance to one part of the vexed historiography of the two explorers, that record is set straight. Amundsen's troubled and contradictory attitude towards his animals is also explored and common misconceptions about Scott's views on the use of dogs for transport are confuted.
Analogy is priming, but relations are not transformations
Authors: Costello Fintan J. 
Published: July 2008

AbstractLeech et al. make two proposals: that relational priming is central to analogy, and that relations between objects are best represented as transformations of those objects. Although their account of analogy as relational priming is a useful contribution to our understanding of analogical development, in this commentary I show that relations in general cannot be represented by transformations.
Relational priming is to analogy-making as one-ball juggling is to seven-ball juggling
Authors: French Robert M. 
Published: July 2008

AbstractRelational priming is argued to be a deeply inadequate model of analogy-making because of its intrinsic inability to do analogies where the base and target domains share no common attributes and the mapped relations are different. Leech et al. rely on carefully handcrafted representations to allow their model to make a complex analogy, seemingly unaware of the debate on this issue fifteen years ago. Finally, they incorrectly assume the existence of fixed, context-independent relations between objects.
Analogical inferences are central to analogy
Authors: Markman Arthur B. , Laux Jeffrey P. 
Published: July 2008

AbstractIt is important to take a developmental approach to the problem of analogy. One limitation of this approach, however, is that it does not deal with the complexity of making analogical inferences. There are a few key principles of analogical inference that are not well captured by the analogical relational priming (ARP) model.
Creativity or mental illness: Possible errors of relational priming in neural networks of the brain
Authors: Swain James E. , Swain John D. 
Published: July 2008

AbstractIf connectionist computational models explain the acquisition of complex cognitive skills, errors in such models would also help explain unusual brain activity such as in creativity – as well as in mental illness, including childhood onset problems with social behaviors in autism, the inability to maintain focus in attention deficit and hyperactivity disorder (ADHD), and the lack of motivation of depression disorders.