Female mate-choice drives the evolution of male-biased dispersal in a social mammal.

Dispersal has a significant impact on lifetime reproductive success, and is often more prevalent in one sex than the other. In group-living mammals, dispersal is normally male-biased and in theory this sexual bias could be a response by males to female mate preferences, competition for access to females or resources, or the result of males avoiding inbreeding. There is a lack of studies on social mammals that simultaneously assess these factors and measure the fitness consequences of male dispersal decisions. Here we show that male-biased dispersal in the spotted hyaena (Crocuta crocuta) most probably results from an adaptive response by males to simple female mate-choice rules that have evolved to avoid inbreeding. Microsatellite profiling revealed that females preferred sires that were born into or immigrated into the female's group after the female was born. Furthermore, young females preferred short-tenured sires and older females preferred longer-tenured sires. Males responded to these female mate preferences by initiating their reproductive careers in groups containing the highest number of young females. As a consequence, 11% of males started their reproductive career in their natal group and 89% of males dispersed. Males that started reproduction in groups containing the highest number of young females had a higher long-term reproductive success than males that did not. The female mate-choice rules ensured that females effectively avoided inbreeding without the need to discriminate directly against close kin or males born in their own group, or to favour immigrant males. The extent of male dispersal as a response to such female mate preferences depends on the demographic structure of breeding groups, rather than the genetic relatedness between females and males.

Prolonged storage of epididymal spermatozoa does not affect their capacity to fertilise in vitro-matured domestic cat (Felis catus) oocytes when using ICSI.

The impact of different storage conditions of epididymal spermatozoa (including prolonged storage, cryopreservation and freeze-drying) on their fertilisation capacity was tested using intracytoplasmic sperm injection (ICSI). This kind of information is urgently needed when applying assisted reproductive technology to endangered felids in zoos. In particular, the utilisation of epididymal spermatozoa of castrated or deceased felids often requires time-consuming transportation and is therefore susceptible to loss of gamete quality. Sperm cells were stored at 4 °C for up to 72 h followed by cryopreservation or freeze-drying. Thawed motile and immotile spermatozoa were used for ICSI and the embryo cleavage rate was assessed 36 h after injection. A significant impact on the fertilisation rate of oocytes could only be detected when using immotile thawed or rehydrated spermatozoa. Cryopreservation or storage at 4 °C showed no influence. The simulation of transport conditions using domestic cat spermatozoa revealed that in vitro production of felid embryos with gametes from euthanised individuals is possible if testes are stored cool and arrive at the laboratory within 72 h. An essential prerequisite is the application of ICSI to achieve fertilisation even with single motile spermatozoa. Additional cryopreservation of spermatozoa after transportation is possible and will allow the establishment of a sperm bank for felids.

Comparative investigations on digestion in grazing (Ceratotherium simum) and browsing (Diceros bicornis) rhinoceroses.

Rhinoceroses represent the largest extant herbivores with extensive dietary specialization for plant groups like browse (black rhino Diceros bicornis) or grass (white rhino Ceratotherium simum). However, it is not clear to what extent such diet selection patterns are reflected in adaptations of digestive physiology of the respective feeding types. In this study, feeding trials with four black and five white rhinos were conducted in four zoos. The animals had ad libitum access to the same batch of grass hay (second cut; neutral detergent fiber (NDF) 63% dry matter (DM), crude protein 10.2% DM). Total intake, fecal N content, in vitro digestibility of NDF residues of feces, fecal particle size and mean retention time (MRT) of particles (Cr-mordanted fiber; 1-2mm) and fluid (Co-EDTA) were quantified. The average daily DM intake was 70+/-12 g/kg BW(0.75) for white and 73+/-10 g/kg BW(0.75) for black rhinos. In the in vitro fermentation test fecal NDF residues of black rhinos resulted in higher gas productions at fermentation times of 12 to 24h, indicating that white rhinos have a superior capacity to digest NDF. Average MRT for fluids and particles was 28+/-4h and 43+/-5h in white and 34+/-4h and 39+/-4h in black rhinos. The selectivity factor (SF=MRT(particle)/MRT(fluid)) was higher for white (1.5+/-0.2) than for black rhinos (1.2+/-0.1) (p=0.016). In a comparison of 12 ruminant and 3 rhino species, SF was correlated to percentage of grass in diet (R=0.75). Mean fecal particle size was higher in white (9.1+/-1.94 mm) than in black rhinos (6.1+/-0.79 mm) (p=0.016). The results demonstrate differences between white and black rhinos in terms of retention times and fiber digestibility. The more selective retention of particles by the white rhino corresponds with the higher digestion of fiber measured indirectly. Furthermore there is indication for a general pattern of high SF in grazing ruminants and rhinos. The difference in fecal particle size between both rhino species might be due to the considerable difference in body weight.

Comparative ingestive mastication in domestic horses and cattle: a pilot investigation.

It is often assumed that horses chew food more intensively during ingestion than cattle, which - as ruminants - complete part of the mastication during rumination. This has been proposed as a reason for more robust mandibles, larger masseter insertion areas and larger masseter muscles in horses as compared to cattle and other grazing ruminants. In this study, we evaluate results of comparative feeding trials with three horses (338-629 kg) and three cows (404-786 kg), on four different roughages. Ingestion time (s/g dry matter) and chewing intensity (chews/g dry matter) differed among animals within a species, indicating an influence of body mass, and differed significantly between different forages. However, although numerical differences clearly suggest that horses have longer ingestion times and higher chewing intensities on high-fibre roughage than do cattle, this could not be proven in this dataset, most likely because of the small number of individuals sampled. Further studies are required to corroborate the suspected ingestive behaviour difference between equids and ruminants.

Split-sample comparison of directional and liquid nitrogen vapour freezing method on post-thaw semen quality in white rhinoceroses (Ceratotherium simum simum and Ceratotherium simum cottoni).

To increase the quality of cryopreserved sperm in white rhinoceros, the liquid nitrogen vapour (LN vapour) freezing and the multi-thermal gradient directional freezing methods were compared. Sixteen white rhinoceros (Ceratotherium simum sp.) were electro-ejaculated. Semen samples were diluted with cryoextender (Tris, lactose, egg-yolk, DMSO) and aliquoted into straws for LN vapour freezing, and glass hollow tubes for directional freezing. The sperm quality was evaluated before and after freezing by assessing the following parameters: motility, morphologic state, acrosomal integrity and plasma membrane function and integrity (i.e. sperm viability) as defined by the hypo-osmotic swelling. Directional freezing improved the sperm viability by 5.6% (p<0.005), progressive motility score by 34.7% and sperm motility index (SMI) by 8.1% (p<0.005) versus LN vapour freezing. When data was categorized into groups of low (<19%), moderate (20-39%) and high (>40%) percentages of morphologically normal, directional freezing (DF) resulted in 31.4% less abnormal acrosomes for the low quality group as well as 18.7% increase in intact acrosomes and 10.9% increase in motility for the high quality group compared to LN vapour freezing (LN) (p<0.01, p<0.03, p<0.01, respectively). LN showed a significant reduction in sperm head volume (5.7%, p<0.05) compared to the prefreeze; whereas, no significant reduction in head volume was demonstrated after DF. Several additives (xanthenuric acid, cytochalasin D, potassium, EDTA) to the basic cryoextender provided no significant improvement in spermatozoal survival after directional freezing. In conclusion, directional freezing proved to facilitate higher gamete survival compared to LN vapour freezing. This is especially effective in ejaculates of low sperm quality and is important in endangered species where high quality semen donors are often not accessible. These results suggest that directional freezing could be valuable particularly for species with limited freezability of spermatozoa.

No easy solution for the fractionation of faecal nitrogen in captive wild herbivores: results of a pilot study.

Faecal nitrogen (FN) concentration is used as a marker for habitat quality and digestive efficiency in free-ranging herbivores. In herbivores, FN can be separated into undigested plant N (analysed as the N concentration of the neutral detergent residue) and metabolic faecal N (MFN). It has been suggested that by differential analysis of the faecal fibre-bound N, the MFN fraction can be further split into a bacterial N and an endogenous N fraction [Hesta et al., Br. J. Nutr. 90 (2003) 1007]. We applied these methods to 96 faecal samples of 48 mammalian herbivore species from zoos. Species were grouped into coprophageous and non-coprophageous hindgut fermenters and ruminating and non-ruminating foregut fermenters. Diet was not controlled. The FN decreased with body mass, possibly reflecting higher proportions of concentrates in diets of smaller animals. The proportion of MFN increased with FN, indicating that higher quality food might enhance the gastrointestinal bacterial flora. The only outlier to this pattern was the lesser panda (Ailurus fulgens), confirming the low relevance of fermentative digestion in this herbivorous 'carnivore'. No relevant differences between the four digestion types were noted. The proportion of endogenous faecal N (32-80% of FN) was always higher than that of bacterial faecal N (7-30%), which contradicts basal understanding of herbivore digestive physiology. Thus, the method of Hesta et al. (2003) does not appear applicable to herbivores. While the results do not exclude the possibility that detailed differences might occur between digestion types, they indicate a high degree of similarity between herbivores that rely on bacterial fermentation, regardless of their digestion type, with respect to metabolic faecal losses.

Physical characteristics of reticuloruminal contents of oxen in relation to forage type and time after feeding.

The stratification of reticulorumen (RR) contents has been described in domestic ruminants, but suspected to be absent in certain wild ruminant species. To investigate how such stratification could be quantified, we tested variables indicating stratification in three oxen with rumen cannulae, fed once daily for 3 h, one of three different forages (fresh grass FG, grass hay GH, lucerne hay LH). Ingesta samples from dorsal rumen (DR), ventral rumen (VR) and reticulum (RET) were taken at 0, 3, 6, 12 and 24 h after the last meal and analyzed for dry matter (DM) concentration, mean particle size and proportion of floating/sedimenting particles. Viscosity was measured in centrifuged RR fluid. There was no relevant variation in rumen fluid viscosity over time or with feeding regime. Dry matter content in DR was always higher than in VR or RET and increased after feeding. When LH and FG were fed, DR always contained larger particles than VR, except at 6 and 12 h of feeding GH. The proportion of floating particles was higher in DR than VR except at GH 6 h and GR between 6 and 12 h. The floating particle fraction mostly contained larger particles, except for GH 3 h in both DR and VR and for FG 3-12 h in DR. Changes in the distribution of particle size and proportion of floating particles over time comply with the theoretical course of fermentative digestion for different forages, but make these variables unreliable indicators of stratification in less controlled settings, such as investigations in wild ruminants. In contrast, viscosity of rumen fluids appears constant over time and feeding regime and might be used as a species-specific variable. The difference in DM content in DR and VR is a reliable indicator for RR contents stratification characterized by an oversaturation of the contents with fluid, leading to lower VR DM contents.

Changes in body weight, hematology and serum chemistry in captive plains viscachas (Lagostomus maximus) with presumptive diabetes type II after a diet change.

We report body weights (BW) and blood and serum analyses for 6 fully mature and 8 not-yet-mature captive plains viscachas before and 3, 6 and 9 months after switching from a low-fiber, high-energy diet to a high-fiber, low-energy diet. Initially, body weights, serum glucose, fructosamine and cholesterol levels were above the reference range in the fully mature animals. Furthermore, 4 of these animals had bilateral cataracts. After the diet change, these parameters dropped into the reference range. However, 9 months later, a slightly increased BW became evident again. The findings are consistent with a type II diabetes mellitus and underline the importance of dietary prevention.

Quantification of Enterobacteriaceae in faeces of captive black rhinoceros (Diceros bicornis) in relation to dietary tannin supplementation.

Free-ranging browsing herbivores ingest a range of secondary plant compounds, such as tannins, with their natural diet. As many of these substances have been shown to have antibacterial properties, it could be speculated that a lack of such compounds in captive zoo diets could favour the growth of potentially pathogenic intestinal bacteria. The effect of a supplementation of a conventional diet (N, consisting mainly of grass hay and/or lucerne hay and pelleted compound feeds) fed to eight captive black rhinoceroses (Diceros bicornis) from three zoological institutions with either tannic acid (T), a source of hydrolysable tannins, or quebracho (Q), a source of condensed tannins, was investigated. The number of faecal colony forming units (CFU) of Enterobactericeae was determined by colony count of dilution series from fresh faeces applied to MacConkey agar plates. Tannins were added to the diets at approximately 5-15 g/kg dry matter, depending on the varying intake of roughage and compound feeds by the animals. There was no difference in the number of CFU between diets N (95.0 x 10(5) +/- 225.3 x 10(5)/g fresh faeces) and T (164.3 x 10(5) +/- 225.1 x 10(5)/g fresh faeces); in contrast, diet Q led to a significant reduction in CFU (4.3 x 10(5) +/- 6.5 x 10(5)/g fresh faeces) compared with the other diets. These findings suggest that condensed tannins could have the potential to reduce the number of potentially pathogenic intestinal bacteria, and that the deliberate inclusion of tannin sources in the diets of captive wild animals should be further investigated. The fact that tannic acid, shown to have antibacterial effects in various in vitro studies, did not have an effect in this study, emphasizes that the relevance of tannin supplementation for intestinal health must be verified in vivo.

Fatty acid status in captive and free-ranging black rhinoceroses (Diceros bicornis).

The fatty acid (FA) patterns of plasma/serum triglycerides (TG), phospholipids (PL) and cholesteryl esters (CE) of captive and free-ranging black rhinoceroses (Diceros bicornis) were investigated. Free-ranging animals (n = 28) stemmed from four different regions. Captive animals sampled included specimens from North American (n = 11) and three different European facilities (n = 6). The European animals were tested on 1-4 different diets, resulting in a total of 15 blood samples. Regardless of differences between the free-ranging animals from different regions, differences between captive and free-ranging animals were relatively uniform: captive animals had higher overall proportions of polyunsaturated fatty acid (PUFA), due to levels of linoleic acid (LA, 18:2n6) that were drastically increased as compared to free-ranging animals. In contrast, levels of alpha-linolenic acid (ALA, 18:3n3) were consistently lower on conventional zoo diets. n6/n3 ratios for TG, PL and CE were 1.6, 10 and 8 in samples from free-ranging animals, respectively, as compared to 4.1-16.3, 16-148 and 40-277 in samples from captive animals. There was a distinct correlation between the proportion of grain-based products (commercial concentrates, plain grains and bread) in the diets of the European animals and the measured levels of n6 PUFA. An animal from a facility with a very low proportion of grain products in the diet nevertheless had high LA readings, most probably due to the use of sunflower oil as 2% (dry matter basis) of its diet. One animal that received a high proportion of grass meal pellets due to an oral disease had increased ALA contents after the diet change. These results allow conclusions on the suitability of diets fed in captivity: the black rhinoceros is prone to several uncommon diseases that have been suspected to be linked to oxidative damage, possibly due to the disposition of this species to excessive iron storage. An unnatural dietary loading with PUFAs would exacerbate this problem. Additionally, n6 FAs are known as precursors of pro-inflammatory mediators, and their overrepresentation could therefore exacerbate any inflammatory processes. Therefore, the current practice of using grain-based feeds as major ingredients in captive rhinoceros diets is discouraged. Diet items containing ALA (a precursor of anti-inflammatory mediators) such as, fresh grass, fresh browse, the respective silages should be included at higher levels in diets for captive black rhinoceroses. Grass meal pellets, although a good source of ALA and linked with high levels of ALA in an animal of this study, must be chosen with care for black rhinoceroses due to their particular proneness for high iron contents.

Canine borreliosis: a laboratory diagnostic trial.

The aim of this study was to investigate samples from dogs suggestive of active canine borreliosis (group A) by culture and PCR and the detection of antibodies against Borrelia burgdorferi sensu lato in order to confirm a presumptive clinical diagnosis of canine borreliosis by laboratory results. Criteria for such a diagnosis were: history of tick exposure, lameness, neurological signs, nephropathy, lethargy, anorexia, and fever. A total of 302 samples comprising EDTA blood, urine, synovial fluid, cerebrospinal fluid, and tissue (skin, synovial membrane, kidney) from 98 dogs (26 with arthritis, 46 with neurological signs, 21 with nephropathy, 5 with non-specific symptoms) were collected and examined. Moreover, 55 healthy dogs (group B) and 236 dogs with symptoms or injuries unlikely to be associated with borreliosis (group C) were included in this study. Blood serum samples collected from all individuals (n=389) were analysed by ELISA. Twenty-one (21%) out of 98 dogs from group A, 4 (7%) out of 55 from group B and 15 (6%) out of 236 dogs from group C were positive for antibodies against B. burgdorferi sensu lato. The seroprevalences between groups A, B and C differed significantly. None of the corresponding samples investigated by PCR and culture were positive for spirochetal DNA or viable spirochetes. Borrelia afzelii was grown from one EDTA-blood sample but the corresponding blood serum sample remained antibody-negative. Consequently, the etiologic role of B. afzelii in this case is unclear. In approximately 40% of the presumptive canine borreliosis cases, other lesions have been found to be responsible for clinical signs. This study affirms that a definitive diagnosis of canine borreliosis cannot be made by clinical symptoms and serology based on a single consultation. Moreover, this study clearly revealed that the diagnostic sensitivity is enhanced by a thorough consideration and exclusion of other diseases.

On the rational selection of test series. 1. Principal component method combined with multidimensional mapping.

A method for the rational selection of optimal test series with high data variance and low collinearities is presented (PCMM method). The method combines the technique of multidimensional mapping originally introduced by Wootton and colleagues with the principal component method, and it is superior to other selection methods with respect to its collinearity decreasing power. Two examples of the application of PCMM are given, and the results are compared with corresponding results from other selection techniques.

On the rational selection of test series. 2. Two-dimensional mapping of intraclass correlation matrices.

A rational design of optimal test series can be performed by two-dimensional mapping of intraclass correlation matrices (TMIC method). The method results in a two-dimensional map from which substituents can be selected by simple inspection. Different test series can be obtained from the same map so that synthetic feasibility can easily be taken into account. The approach closely corresponds to the usual way of thinking of organic chemists, and the test series evaluated for an example show high data variance and low collinearities.

Substructural QSAR approaches and topological pharmacophores.

For large and diverse data sets, simple QSAR methods based on linear and additive models can no longer be applied. In such cases topological methods using descriptors directly derivable from two-dimensional chemical structures provide a useful alternative. The results of such analyses can be used for lead optimization, to guide biological testing and even aid in the design of novel compounds. Various types of topological descriptors and algorithms are briefly discussed. Which of those is to be selected depends on the objective of the investigation and the properties of the data set. Two new methods, LOGANA and LOCON, are discussed in some more detail. With the help of these methods, substructural patterns ("topological pharmacophores") characteristic of compounds possessing a certain biological property can be evaluated. Both methods are designed in such a way that full use can be made of the data handling capacity of computers while maintaining an optimal impact of the experience of the researcher. They are model-free and do not require any mathematical knowledge. While LOGANA deals with semiquantitative or even qualitative biological data, LOCON can be applied to activity data on a continuous scale. The basic procedure in both cases consists in the stepwise combination of substructural descriptors by the logical operations "and," "or" and "not." With a simple example the utility of the methods is demonstrated.

Comparison of glycoprotein B (gB) variants of the elephant endotheliotropic herpesvirus (EEHV) isolated from Asian elephants (Elephas maximus).

The recently described elephant endotheliotropic herpesviruses (EEHV) have been associated with the deaths of numerous captive elephants. A proposed tool for the detection of EEHV infection in elephants is the PCR-based screening for EEHV-DNA in whole blood samples. Unfortunately, this detection method has only been successful in post-mortem analyses or in animals already displaying clinical signs of EEHV disease, thus rendering this method unsuitable for identification of carrier elephants. Here, we focus on glycoprotein B (gB) for serologic assay development, since gB is an envelope protein known to induce a neutralising antibody response in other herpesvirus infections. We sequenced the entire gB gene from five Asian elephants with EEHV, representing four different gB variants. Computer-aided methods were used to predict functionally important regions within EEHVgB. An extra-cytoplasmic region of 153 amino acids was predicted to be under positive selection and may potentially contain antigenic determinants that will be useful for future serologic assay development.

Strigea falconispalumbi in Eurasian buzzards from Germany.

Eighty-three free-living Eurasian buzzards (Buteo buteo) from three different areas in Germany were examined for adult stages and the metacercaria of the trematode Strigea falconispalumbi. Prevalences of adult parasites in the small intestine was 36% (Berlin/Brandenburg), 28% (Lower Saxony) and 3% (Baden-Württemberg). Metacercaria in the connective tissue of the neck were found in 58%, 55%, and 10% of birds from the respective areas. Significant differences in the prevalence of S. falconispalumbi adults and metacercaria between the areas were attributed to the different abundance of freshwater which is the key habitat for two intermediate hosts.

Serologic evidence of bovine viral diarrhea virus in free-ranging rabbits from Germany.

From 1993 to 1995, 100 blood samples and 97 spleen samples of free-ranging rabbits (Oryctolagus cuniculus) from northern Germany were tested for prevalence of different bovine viral diarrhea virus (BVDV) antibodies and BVDV antigen, respectively. Forty sera (40%) were positive for antibodies to one or more of three cytopathogenic BVDV strains (NADL, Grub 313/83, and roe deer isolate SH9/11). Microneutralization test (NT) titers ranged from 5 to 13. Moreover, 13 of 35 NT positive sera also were positive by enzyme-linked immunosorbent assay for detection of anti-BVDV antibodies. Therefore, we assume that the rabbits either had passively acquired antibodies or had experienced natural infection with BVDV. Furthermore, 97 spleen samples were used for attempts to isolate BVDV and tested by reverse transcription polymerase chain reaction for viral nucleic acid using various protocols. Bovine viral diarrhea virus was not identified in these samples.

Laminitis in Przewalski horses kept in a semireserve.

Semireserves were created by the European Conservation Project for scientific research in preparation for reintroduction in the wilderness. They are defined as enclosures large enough to carry a group of Przewalski horses throughout the year without any additional feeding. The semireserve offers diverse opportunities for significant scientific research. As part of a general screening program, the hoof development in a group of Przewalski horses was investigated in the semireserve Schorfheide near Berlin. Since the foundation of this semireserve in 1992, veterinary treatment was not necessary with the exception of hoof trimming in two animals in 1993. However, major health problems were encountered in the spring of 1999, when three other mares showed signs of laminitis. The initial diagnosis by the authors and the local veterinary surgeon based on observation of behaviour, gait, stance, walk and trot of three mares whose initial weights were higher than those of the healthy mares. The initial diagnosis was confirmed by palpation and the occurrence of very deep horn rings on all hooves and a laminitic horn ring on the right front hoof of one mare. An adequate laminitic therapy was not possible under the conditions of a semireserve. The applied management aimed at two goals: 1. To reduce endotoxin production and acidosis in the horses by reducing the ingestion of carbohydrate rich food. 2. To reduce the mares level of activity and to prevent tearing of the suspensory apparatus of the coffin bone. To achieve these two goals it was decided to remove the three laminitic mares from the rich pasture in the main part of the semireserve and to confine them onto the poorer pasture of the small separately fenced area. All three affected mares had fully recovered from their laminitic condition. Prevention of grass laminitis can be achieved by the following measures: 1. Reduction in grass intake could be achieved by increasing the grazing pressure by an increase in stocking rate of the horses or mixed grazing with another species such as sheep. 2. A longer term solution to the problem may well be to sow specific varieties of grass with lower concentrations of water soluble carbohydrate.

Plasma and erythrocyte fatty acids in captive Asian (Elephas maximus) and African (Loxodonta africana) elephants.

The fatty acid components of the plasma triglycerides and the phospholipid fractions of the red blood cells of a captive group of two African (Loxodonta africana) and four Asian (Elephas maximus) elephants were investigated. All the animals received the same diet of hay, fruits and vegetables, and concentrates. A comparison with data from free-ranging African elephants or Asian work-camp elephants showed that the captive elephants had lower proportions of polyunsaturated fatty acids (PUFAs), and for several lipid fractions a higher n-6:n-3 ratio, than their counterparts in the wild or under the more natural, in terms of diet, work-camp conditions. The difference in PUFA content was smaller in the African than in the Asian elephants. The captive Asian elephants tended to have lower levels of n-3 and total unsaturated fatty acids in their red blood cells than the captive African elephants.

Informational content of discrete data from parallel test with similar biological objects: selection of key tests.

Results from parallel tests with similar biological objects are frequently interrelated. If the data are discrete which is a typical situation in biological mass-screening, the information-theoretical concept of Shannon's entropy can be used to unreval redundancies within such test and to recognize tests with high informational content. This concept was applied to two examples from the screening for fungicidal activity, and the results were compared with activity-activity relationships obtained from pattern recognition and with variance analysis. There was good agreement, and the entropy calculation indeed yielded a very sensitive measure for the informational structure of the data. If the informational structure is known redundant tests may be eliminated. If the evaluation of quantitative structure-activity relationships is attempted it is furthermore possible to restrict the calculations to key tests with high information.