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1.
Previous investigations have clearly shown the existence of associations between halothane sensitivity, the H blood group system and the PHI enzyme system in pigs (Rasmusen & Christian 1976, Jørgensen et al. 1976). These associations which have considerable practical interest are most probably linkage phenomenons (Jørgensen 1977, Andresen & Jensen 1977). The major recessive locus for halothane sensitivity (HAL) comprises the two alleles N and n, n being responsible for halothane sensitivity. The distances between this locus and the loci for H and PHI are still not known exactly. This communication aims at clarifying these problems.  相似文献   

2.
Bovine respiratory syncytial virus (BRSV) caused a large epizootic of acute respiratory disease in Japan in 1968—69 (Inaba et al. 1970, Inaba et al. 1972). A much smaller outbreak occurred in Switzerland (Paccaud & Jacquier 1970). In Belgium the virus has been isolated from an outbreak of respiratory disease (Wellemans et al. 1970). BRSV has later been proved an important causal agent of respiratory disorders in the same country (Wellemans & Leiinen 1975). In England and USA the virus has caused and been isolated from outbreaks of acute respiratory disease in calves (Jacobs & Edington 1971, Rosenquist 1974, Smith et al. 1974). In Denmark BRSV has sporadically been isolated from pneumonic calf lungs (Bitsch et al. 1976).  相似文献   

3.
Lactic acid bacteria are considered indigenous members of the gastrointestinal microflora in a number of animal species (Savage 1977a). Some intestinal strains of lactobacilli and streptococci are aWe to adhere to stratified squamous epithelium of some animals (Tannock et al. 1987), in the non-secreting part of the stomach of piglets (Barrow et al. 1980, Fuller et al. 1978) and rodents (Tannock et al. 1982), and in the crop of poultry (Fuller 1978). The presence of lactic acid bacteria in the digestive tract is believed to be of beneficial value to the host animal (Fuller 1989). The production of organic acids in the stomach or the crop helps maintaining a low pH which may be important for inhibiting the colonization of potentially pathogenic bacteria, particularly in the newborn animal (Barrow et al 1980, Fuller 1977, Fuller 1978). The adhesion of lactobacilli to squamous epithelium is host specific: strains capable of adhering to the epithelium of piglets are usually not able to adhere in rodents or poultry and vice versa (Fuller 1978, Lin & Savage 1984, Tannock et al 1982). Adhesion of lactic acid bacterial strains to other epithelia than stratified squamous epithelium has been reported. Thus, the attachment of lactobacilli to cells from the secreting epithelium of the murine stomach (Kotarski & Savage 1979), to intestinal cells of humans (Goldin & Gorbach 1987), and to columnar epithelial cells of piglets and calves (Mäyrä-Mäkinen et al 1983) has been demonstrated using in vitro methods. In another study the in vivo attachment of Enterococcus faecium to duodenal epithelium of gnotobi-otic chickens was demonstrated (Fuller et al 1981). Recent research indicated that in adult mink lactic acid bacteria are not indigenous members of the intestinal flora, and they do not attach to epithelium in any part of the gastrointestinal tract (Federsen & Jørgensen 1992). The present paper presents evidence that Gram positive cocci may colonize the gut of suckling mink kits and attach to the gut mucosa.  相似文献   

4.
Porcine toxoplasmosis generally occurs as a latent disease in adolescent and adult pigs, but now and then also manifests itself as a fatal congenital disease in piglets. It is known to occur in USA (Farrel et al. 1952), Germany (Becker 1954), Denmark (Momberg-Jørgensen 1956), Mexico (Varela et al. 1956), Japan (Sato et al. 1958), England (Harding et al. 1961) and Sweden (Hansen et al. to be published).  相似文献   

5.
Lake Sentiz and Lake Chozas are two small water bodies in the Province of León (NW Spain). The former is mesotrophic and the latter went from oligotrophic to turbid in 1997, due to introduction of an invasive allochthonous crayfish Procambarus clarkii (Rodríguez et al., 2003, Rodríguez et al., 2005, Marchi et al., 2011a, Marchi et al., 2011b). We set out to study health status of the two ecosystems by the joint use of different but correlated ecological indicators, supplementing the values obtained by monitoring campaigns. We examine three scenarios: (1) Lake Sentiz, (2) Lake Chozas before and (3) Lake Chozas after the biological invasion. We evaluate eco-exergy, emergy and eco-exergy–empower ratio, three holistic ecological indicators based on the thermodynamics of far-from-equilibrium systems. When structural changes take place in ecosystems it is recommended to apply holistic thermodynamic indicators as presented in Jørgensen et al., 2010a, Jørgensen et al., 2010b. We propose their joint application for a complete overview of the monetary value of natural capital, because they provide information added to statistical analysis and direct measurement. The aim is to determine which of these indicators best represents the effects of eutrophication and perturbations caused by alien species in the two freshwater systems. The eco-exergy–empower ratio gives the best results, since it clearly indicates lake efficiency in transforming direct and indirect solar energy inputs into organization. The eco-exergy (work capacity) results are used to estimate ecosystem services and quantify the economic value of lake natural capital. Calculation of ecosystem services on an eco-exergy basis provides good indications of monetary gains or losses possible in perturbed systems, including eutrophic or invaded ecosystems. This is not surprising, because work capacities include all possible services offered by ecosystems, not only the services actually used by humans. Eco-exergy and the eco-exergy–empower ratio can be guidelines for the calculation of ecosystem services, although they give only a partial indication of the environmental costs and benefits of a given level of information. The present results suggest political and economic considerations and solutions, and are a useful example for organisations involved in environmental management of pollution and biological invasions by exotic species.  相似文献   

6.
doi:10.1111/j.1741‐2358.2009.00285.x
Evaluation of three indices for biofilm accumulation on complete dentures Objectives: The objective of this study was to evaluate the accuracy and reproducibility of three complete denture biofilm indices (Prosthesis Hygiene Index; Jeganathan et al. Index; Budtz‐Jørgensen Index) by means of a computerised comparison method. Background: Clinical studies into denture hygiene have employed a large number of biofilm indices among their outcome variables. However, the knowledge about the validity of these indices is still scarce. Materials and methods: Sixty‐two complete denture wearers were selected. The internal surfaces of the upper complete dentures were stained (5% erythrosine) and photographed. The slides were projected on paper, and the biofilm indices were applied over the photos by means of a scoring method. For the computerised method, the areas (total and biofilm‐covered) were measured by dedicated software (Image Tool). In addition, to compare the results of the computerised method and Prosthetic Hygiene Index, a new scoring scale (including four and five graded) was introduced. For the Jeganathan et al. and Budtz‐Jørgensen indices, the original scales were used. Values for each index were compared with the computerised method by the Friedman test. Their reproducibility was measured by means of weighed κ. Significance for both tests was set at 0.05. Results: The indices tested provided similar mean measures but they tended to overestimate biofilm coverage when compared with the computerised method (p < 0.001). Agreement between the Prosthesis Hygiene Index and the computerised method was not significant, regardless of the scale used. Jeghanathan et al. Index showed weak agreement, and consistent results were found for Budtz‐Jorgensen Index (κ = 0.19 and 0.39 respectively). Conclusion: Assessment of accuracy for the biofilm indices showed instrument bias that was similar among the tested methods. Weak inter‐instrument reproducibility was found for the indices, except for the Budtz‐Jørgensen Index. This should be the method of choice for clinical studies when more sophisticated approaches are not possible.  相似文献   

7.
Neospora caninum is a recently recognized cyst-forming coccidian parasite associated with severe encephalomyelitis and myositis in dogs of different breeds and ages (Bjerkås et al 1984, Bjerkås & Presthus 1988, Dubey et al. 1988), but has for many years been misdiagnosed as Toxoplasma gondii. In some dogs, the main clinical sign has been attributed to polyradiculoneuritis (Dubey et al. 1988, Cuddon et al. 1992). Furthermore, ulcerative dermatitis (Dubey et al. 1988) and megaoesophagus have been reported (Wolf et al. 1991). The life cycle of the parasite and mode of infection have not been clarified, but transplacental infection seems so far to be the natural route of transmission between intermediate hosts (Dubey & Lindsay 1989). It has been speculated that the disease in young and adult dogs might be due to reactivation of a persistent infection because corticosteroid therapy can activate a latent N. caninum infection (Dubey & Lindsay 1993).  相似文献   

8.
9.
Einarsson  S.  Soosalu  O.  Swensson  T.  Viring  S. 《Acta veterinaria Scandinavica》1972,13(3):446-448
Satisfactory conception rates of deep frozen boar spermatozoa were obtained, with insemination by way of the cervix, after thawing the deep frozen spermatozoa in boar seminal plasma, both in preliminary trials (Crabo & Einarsson 1971, Crabo et al. 1972 b) and in a large field trial (Einarsson et al. 1972). Fertility with pellet frozen boar spermatozoa, thawed without dilution, was reported by Graham et al. (1971 a, b) and Pursel & Johnson (1971).  相似文献   

10.
According to Jørgensen, the definition of reintroductions is crucial to their proper implementation and she highlights a number of ambiguities in existing definitions, particularly associated with the concept of historic range. We could not agree more and have incorporated her suggested term of “indigenous range” rather than “historic range” into the current revision of the InternationalUnion for the Conservation of Nature (IUCN) Guidelines for Reintroductions and other Conservation Translocations (in preparation by IUCN Species Survival Commission Reintroduction and Invasive Species Specialist Groups). We also agree with Jørgensen's interpretation that reintroductions are not always necessitated by humans causing the extirpation of species. However, we disagree with other aspects of Jørgensen's argument such as the critique of Seddon, the interpretation of previous IUCN guidance documents, and the recommendation that the conservation community “rethink the basic definition of reintroduction” rather than moving toward other translocation‐based interventions. With regard to the latter point, we emphasize that reintroductions are part of a spectrum of translocations and to focus on reintroductions alone would overlook the fact that introductions beyond a species' indigenous range are being attempted. The new revision of the IUCN guidelines incorporates the whole conservation translocation spectrum and aims to avoid the ambiguities of previous definitions highlighted by Jørgensen.  相似文献   

11.
Like other lentiviruses, caprine arthritis-encephalitis virus (CAEV) causes persistent infection. The majority of CAEV-infected goats is clinically healthy. Signs of disease are associated with progressive inflammation in one or more organ or tissue systems such as joints, bursae, brain, spinal cord, lungs, and udder (Bulgin 1990, Dawson 1987). In most CAEV- infected females, the mammary gland, which is a target for the virus, is likely to be infected (Kennedy-Stoskopf et al. 1985, Lerondelle et al. 1989). The infection may cause increased somatic cell counts (Post et al. 1984, Nord & Adnoy to be published). The milk mostly appears normal and mastitis may not be suspected. Ryan et al. (1993) and Smith & Cutlip (1988) suggested that susceptibility to bacterial udder infection is enhanced in CAEV-infected goats, in particular with regard to infections due to non-haemolytic Staphylococci. In this study, the prevalence of bacterial udder infections in CAEV-antibody positive goats is compared with that in negative animals.  相似文献   

12.
During the last decade, an increasing number of bovine adenoviruses have been isolated from calves suffering from more, or less, well-defined syndromes. These have consisted of respiratory disorders of varying severity, enteritis, or a combination of both, which in typical cases has been termed “pneumo-enteritis”. These investigations have been reviewed by Darbyshire (1968). Wilcox (1969) isolated adenoviruses from kerato-conjunctivitis (KC) in cattle. Furthermore, strains have been isolated from apparently healthy animals (Darbyshire 1968), and from tissue cultures prepared from various organs from calves such as kidneys (Scho- pov et al. 1968), and testes (Rondhuis 1968, Bartha & Csontos 1969). At the present time 9 serotypes of bovine adenoviruses exist, as determined by neutralization tests, and these have recently been reviewed by Guenov et al. (1970). However, several strains, some from cases of pneumonia (Cole 1970, Lupini et al. 1970) and others from KC (Wilcox 1969) remain to be typed and compared with the known prototypes, thereby enabling possible new serotypes to be identified. So far, serotypes 1 and 2 (Darbyshire et al. 1969), serotype 3 (Darbyshire et al. 1966) and serotypes 4 and 5 (Aldasy et al. 1965) have been shown to cause pneumo-enteritis, and serotype 6 (Rondhuis 1970) a mild respiratory disease in experimentally infected calves. Similarly, KC has been produced experimentally by Wilcox (1970), while the pathogenicity for experimental animals of the other typed and untyped strains remains to be investigated.  相似文献   

13.
The sampling method used is of great importance for the estimation of the microbial activity and biochemical status in ruminal fluid (Stöber & Tiefenbach 1958, Keindorf 1974, Behravesh 1984). Several methods have been used for sampling of ruminal fluid in non-fistulated animals (Sørensen & Schambye 1955, Perk 1958, Schultz & Hiepe 1958, Keindorf & Link 1971). However, the conventional methods of collecting ruminal fluid either by stomach tube (Thygesen probe with a filter ad modum Sørensen & Schambye (1955)), or through a puncture low in the left flank, do not produce representative samples comparable in quality or quantity to samples collected directly through a rumen fistula. The puncture methods usually produce a very small volume of material, and they often leave the cow with an inflammatory reaction in the flank. Many research workers have demonstrated contamination with saliva in samples drawn through a peroral stomach tube, resulting inter alia in a higher pH value than in samples collected through fistula (Dirksen 1970, Behravesh 1984). Since changes in the fermentative reactions of high-yielding cows are receiving much research emphasis today, it has been our aim to construct an instrument suitable for collecting single or continuous samples for diagnostic as well as research purposes, which are comparable in quality and quantity to samples obtained through a rumen fistula. The idea of making the naso-ruminal sampler was inspired by the construction of the COMET Naso-Reticular Instrument (Hekmati et al. 1985).  相似文献   

14.
Several successful attempts have been made to induce swine dysentery in pigs using pure cultures of Treponema hyodysen-teriae (Taylor & Alexander 1971, Harris et al. 1972, Akkermans & Pomper 1973, Hughes et al. 1975). In these studies, either conventional or specific-pathogen-free pigs were used. In the present study, 2 approximately 8 weeks old conventional pigs (Nos. 1 and 2) were purchased and fed the same basic ration as used by Teige et al. (1977). In addition, 10 % cod liver oil was incorporated in the diet at each feeding. After a feeding period of 25 days rectal swabs were applied and examined for the presence of spirochaetes. The pigs were then fed a 3 days old primary and pure culture of T. hyodysenteriae on TSA-S400 medium (Songer et al. 1976). The culture originated from the colon of a pig with swine dysentery (Pig No. 4, Teige et al. 1977). Each pig received the agar contents of 5 petri dishes which were mixed with the food.  相似文献   

15.
Dixon  L. K.  Nelson  B. A.  Priest  R. L. 《Genetica》1984,52(1):63-68
Mice of the genus Peromyscus all have 48 chromosomes. Yet the appearance of the 48 chromosomes is highly variable from species to species (Hsu & Arrighi, 1966, 1968, 1971; Pathak et al., 1973) and even in different populations of the same species (Sparkes & Arakaki, 1966; Ohno et al., 1966; Hsu & Arrighi, 1968; Arakaki et al. 1970; Te & Dawson, 1971; Bradshaw & Hsu, 1972; Murray & Kitchin, 1976). The evolutionary significance of this variation and the mechanisms for its initiation and maintenance have been of interest for quite a few years. However, it was not until the sophisticated chromosome banding techniques became available that mammalian cytogeneticists were able to begin to study the chromosome variation of Peromyscus in some detail. The use of C-banding led Hsu & Arrighi (1971) to the finding that the short arms of chromosomes in three different species of Peromyscus contained constitutive heterochromatin. These results suggested that the variations in the number of acrocentric chromosomes in Peromyscus might be a result of different amounts of heterochromatin. Later studies (Duffey, 1972; Waterbury, 1972; and Pathak et al., 1973) were also consistent with this hypothesis.However, it was soon discovered that not all chromosomal differences among Peromyscus populations are due to heterochromatin changes. Studies by Arighi et al. (1976) and Murray & Kitchin (1976) showed that some chromosomal differences between species and subspecies of Peromyscus are due to pericentric inversions. Thus, it appears that both inversions and the addition of heterochromatin are involved in the evolution of the karyotype of Peromyscus.The purpose of our study was to investigate the chromosomes of Peromyscus maniculatus in different populations in Colorado (U.S.A.) and to test for relationships involving an altitudinal gradient. In the first part of this study, orcein stained chromosomes from three subspecies of mice sampled at nine different altitudes were examined for karyotype variability. In the second part of the study, karyotypes of two subspecies (P. m. rufinus and P. m. luteus), representing high and low altitude populations were examined with Q banding to determine the mechanisms responsible for chromosomal differences.  相似文献   

16.
Human molars from travertine deposits of Witkrans Cave (Gaap Escarpment, northern Cape Province, South Africa) are described. The Witkrans molars were discovered in direct association with later Pleistocene faunal remains and a sample of Middle Stone Age artifacts (Peabody, 1954; Clark, 1971; Sampson, 1974; Klein, 1984; Volman, 1984). The morphology and dimensions of the Witkrans molars resemble remains from other localities of similar age in southern Africa (Singer & Wymer, 1982; Grine & Klein, 1985; Grine et al., 1991; Rightmire & Deacon 1991) but exhibit differences from later Pleistocene occurrences in northern Africa (McBurney et al. 1953; Vallois & Roche, 1958; Ennouchi, 1969; Hublin & Tillier, 1981). These results offer further support for the existence of later Pleistocene human populations south of the Sahara which were distinct from contemporaneous peoples of Mediterranean Africa (Howell, 1978; Brauer, 1984; Rightmire, 1984; Klein 1992).  相似文献   

17.
Streptococcus suis is an important pig pathogen which is associated with respiratory problems, meningitis and less fre-quently with a variety of other conditions(Hommez et al. 1986). S. suis type 1 causes disease mainly in 1–2 week old pigs while serotype 2 is found commoaily in 2–22 week old pigs, S. suis type 2 is a zoonosis. It can cause meningitis and septicaemia in man (Christensen & Kronvall 1985). Several other serotypes of S. suis have also been identified on the basis of the capsular poly-saccharide (Perch et al. 1983, Hommez et al. 1986). We present a case where we isolated S. suis types 1 and 2 from the brain and lungs respectively of the same diseased suckling piglet. This i/s the first reported case of S. suis types 1 and 2 in Finland.  相似文献   

18.
The lichen genus Protopannaria is defined as different from Pannaria, being a bipolar taxon with three (of four) species in the subantarctic region: P. austro-orcadensis (Øvst.) comb. nov. in the western part and P. alcicornis P.M. Jørg. & R.S. Poulsen sp. nov. as well as P. azorellae P.M. Jørg. & R.S. Poulsen sp. nov. in the eastern one (Kerguelen), showing the greatest diversity there.  相似文献   

19.
Several peptide antibiotics have been described as potent inhibitors of bacterial growth. With respect to their biosynthesis, they can be devided into two classes: (i) those that are synthesized by a non-ribosomal mechanism and (ii) those that are ribosomally synthesized. Subtilin and nisin belong to the ribosomally synthesized peptide antibiotics. They contain the rare amino acids dehydroalanine, dehydrobutyrine, meso-lanthionine, and 3-methyl-lanthionine. They are derived from prepeptides which are post-translationally modiffied and have been termed lantibiotics because of their characteristic lanthionine bridges (Schnell et al. 1988). Nisin is the most prominent lantibiotic and is used as a food preservative due to its high potency against certain gram-positive bacteria (Mattick & Hirsch 1944, 1947; Rayman & Hurst 1984). It is produced by Lactococcus lactis strains belonging to serological group N. The potent bactericidal activities of nisin and other lantibiotics are based on depolarization of energized bacterial cytoplasmic membranes. Breakdown of the membrane potential is initiated by the formation of pores through which molecules of low molecular weight are released. A trans-negative membrane potential of 50 to 100 mV is necessary for pore formation by nisin (Ruhr & Sahl 1985; Sahl et al. 1987). Nisin occurs as a partially amphiphilic molecule (Van de Ven et al. 1991). Apart from the detergent-like effect of nisin on cytoplasmic membranes, an inhibition of murein synthesis has also been discussed as the primary effect (Reisinger et al. 1980). In several countries nisin is used to prevent the growth of clostridia in cheese and canned food. The nisin peptide structure was first described by Gross & Morall (1971), and its structural gene was isolated in 1988 (Buchman et al. 1988; Kaletta & Entian 1989). Nisin has two natural variants, nisin A and nisin Z, which differ in a single amino acid residue at position 27 (histidin in nisin A is replaced by asparagin in nisin Z (Mulders et al. 1991; De Vos et al. 1993). Subtilin is produced by Bacillus subtilis ATCC 6633. Its chemical structure was first unravelled by Gross & Kiltz (1973) and its structural gene was isolated in 1988 (Banerjee & Hansen 1988). Subtilin shares strong similarities to nisin with an identical organization of the lanthionine ring structures (Fig. 1), and both lantibiotics possess similar antibiotic activities. Due to its easy genetic analysis B. subtilis became a very suitable model organism for the identification and characterization of genes and proteins involved in lantibiotic biosynthesis. The pathway by which nisin is produced is very similar to that of subtilin, and the proteins involved share significant homologies over the entire proteins (for review see also De Vos et al. 1995b). The respective genes have been identified adjacent to the structural genes, and are organized in operon-like structures (Fig. 2). These genes are responsible for post-translational modification, transport of the modified prepeptide, proteolytic cleavage, and immunity which prevents toxic effects on the producing bacterium. In addition to this, biosynthesis of subtilin and nisin is strongly regulated by a two-component regulatory system which consists of a histidin kinase and a response regulator protein.  相似文献   

20.
Actinobacillosis in pigs seems to be relatively rare and when it does occur, it usually manifests itself as acute septicaemia during the first weeks of life (Zimmermann 1965). Polyarthritis, pneumonia and heart lesions as well as petechial haemorrhages in skin, viscera and kidneys are also frequently found (MacDonald et al. 1976, Jones & Simmons 1971). Both Actinobacillus suis and Actinobacillus equuli have been isolated from such cases (Pedersen 1977).  相似文献   

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