Enterococcus columbae, a species from pigeon intestines

Gram-positive cocci which dominate in the intestinal flora of domestic pigeons were found to constitute a new species of the genus Enterococcus. The strains were most closely related to Enterococcus cecorum, originally described as Streptococcus cecorum, a carboxyphilic species from chicken intestines, and to Enterococcus avium. The pigeon strains resemble E. cecorum and also many E. avium strains in their lack of group D antigen and in being more sensitive to NaCl than other enterococci. The type strain is strain STR 345 (= NCIMB 13013).     

Enterococcal and streptococcal species isolated from faeces of calves, young cattle and dairy cows.

Faeces from non-ruminating calves were found to contain several species of enterococci: Enterococcus avium, Ent. cecorum, Ent. durans, Ent. faecalis, Ent. faecium and Ent. hirae. Enterococcus faecalis was the most frequent. Few of these animals carried streptococci. Streptococcus bovis largely predominated in ruminating calves, young cattle and dairy cows. Other streptococci as well as enterococci were infrequent in dairy cows, but a variety of other streptococci and enterococci were found in the faeces of young ruminating animals.     

Enterococcal and streptococcal species isolated from faeces of calves, young cattle and dairy cows

Faeces from non-ruminating calves were found to contain several species of enterococci: Enterococcus avium, Ent. cecorum, Ent. durans, Ent. faecalis, Ent. faecium and Ent. hirae. Enterococcus faecalis was the most frequent. Few of these animals carried streptococci.
Streptococcus bovis largely predominated in ruminating calves, young cattle and dairy cows. Other streptococci as well as enterococci were infrequent in dairy cows, but a variety of other streptococci and enterococci were found in the faeces of young ruminating animals.     

Composition of the enterococcal and streptococcal intestinal flora of poultry

Identification to species level showed that Enterococcus faecalis and Ent. faecium largely dominated the enterococcal and streptococcal gut flora of 1-d-old chicks. Enterococcus faecalis was rare in 3- to 5-week-old broilers. Two species, Ent. faecium and Streptococcus alactolyticus, were isolated from nearly all broilers examined. Enterococcus hirae and Ent. durans were found in the small intestines of this category of poultry. In layers and parent stock of over 12 weeks of age, Ent. cecorum dominated with Strep. alactolyticus ranking next. Other species were isolated irregularly. Enterococcus avium and Ent. gallinarum, originally described from chickens, were rarely found. These species did not appear to belong to the normal intestinal flora of poultry.     

Composition of the enterococcal and streptococcal intestinal flora of poultry

Identification to species level showed that Enterococcus faecalis and Ent. faecium largely dominated the enterococcal and streptococcal gut flora of 1-d-old chicks. Enterococcus faecalis was rare in 3- to 5-week-old broilers. Two species, Ent. faecium and Streptococcus alactolyticus , were isolated from nearly all broilers examined. Enterococcus hirae and Ent. durans were found in the small intestines of this category of poultry.
In layers and parent stock of over 12 weeks of age, Ent. cecorum dominated with Strep. alactolyticus ranking next. Other species were isolated irregularly. Enterococcus avium and Ent. gallinarum , originally described from chickens, were rarely found. These species did not appear to belong to the normal intestinal flora of poultry.     

Identification and composition of the tonsillar and anal enterococcal and streptococcal flora of dogs and cats

Enterococcus faecalis was the most frequently isolated enterococcal species from anal swabs and tonsils of dogs and cats, although in the anal samples from dogs Ent. hirae was found almost as often as Ent. faecalis. Most Ent.faecium strains from dog tonsils differed from those associated with humans and other animals in that they fermented sorbitol. Typical Ent. avium as well as atypical Ent. avium -like strains were seen in dogs, while the related species Ent. raffinosus was associated with cat tonsils. Enterococcus cecorum also occurred mainly in cats. Certain atypical strains, presumptively identified as Ent. cecorum , shared characteristics with Ent. columbae.
The most frequent streptococcal species in tonsils of cats and dogs were Streptococcus suis and Strep. canis. Streptococcus canis and Strep. bovis predominated in anal swabs. The canine Strep. suis differed from the common porcine strains in fermenting mannitol.
Forty-seven of the 288 isolates examined could not be identified or related to known species. The characteristics of two groups of these bacteria, provisionally called 'Ton 31 group' and 'O7 group' are described.     

Identification and composition of the tonsillar and anal enterococcal and streptococcal flora of dogs and cats.

Enterococcus faecalis was the most frequently isolated enterococcal species from anal swabs and tonsils of dogs and cats, although in the anal samples from dogs Ent. hirae was found almost as often as Ent. faecalis. Most Ent. faecium strains from dog tonsils differed from those associated with humans and other animals in that they fermented sorbitol. Typical Ent. avium as well as atypical Ent. avium-like strains were seen in dogs, while the related species Ent. raffinosus was associated with cat tonsils. Enterococcus cecorum also occurred mainly in cats. Certain atypical strains, presumptively identified as Ent. cecorum, shared characteristics with Ent. columbae. The most frequent streptococcal species in tonsils of cats and dogs were Streptococcus suis and Strep. canis. Streptococcus canis and Strep. bovis predominated in anal swabs. The canine Strep. suis differed from the common porcine strains in fermenting mannitol. Forty-seven of the 288 isolates examined could not be identified or related to known species. The characteristics of two groups of these bacteria, provisionally called 'Ton 31 group' and 'O7 group' are described.     

Evidence for horizontal gene transfer in evolution of elongation factor Tu in enterococci

The elongation factor Tu, encoded by tuf genes, is a GTP binding protein that plays a central role in protein synthesis. One to three tuf genes per genome are present, depending on the bacterial species. Most low-G+C-content gram-positive bacteria carry only one tuf gene. We have designed degenerate PCR primers derived from consensus sequences of the tuf gene to amplify partial tuf sequences from 17 enterococcal species and other phylogenetically related species. The amplified DNA fragments were sequenced either by direct sequencing or by sequencing cloned inserts containing putative amplicons. Two different tuf genes (tufA and tufB) were found in 11 enterococcal species, including Enterococcus avium, Enterococcus casseliflavus, Enterococcus dispar, Enterococcus durans, Enterococcus faecium, Enterococcus gallinarum, Enterococcus hirae, Enterococcus malodoratus, Enterococcus mundtii, Enterococcus pseudoavium, and Enterococcus raffinosus. For the other six enterococcal species (Enterococcus cecorum, Enterococcus columbae, Enterococcus faecalis, Enterococcus sulfureus, Enterococcus saccharolyticus, and Enterococcus solitarius), only the tufA gene was present. Based on 16S rRNA gene sequence analysis, the 11 species having two tuf genes all have a common ancestor, while the six species having only one copy diverged from the enterococcal lineage before that common ancestor. The presence of one or two copies of the tuf gene in enterococci was confirmed by Southern hybridization. Phylogenetic analysis of tuf sequences demonstrated that the enterococcal tufA gene branches with the Bacillus, Listeria, and Staphylococcus genera, while the enterococcal tufB gene clusters with the genera Streptococcus and Lactococcus. Primary structure analysis showed that four amino acid residues encoded within the sequenced regions are conserved and unique to the enterococcal tufB genes and the tuf genes of streptococci and Lactococcus lactis. The data suggest that an ancestral streptococcus or a streptococcus-related species may have horizontally transferred a tuf gene to the common ancestor of the 11 enterococcal species which now carry two tuf genes.     

Identification of enterococci at the species level by sequencing of the genes for D-alanine:D-alanine ligases

A PCR assay based on the use of degenerate oligodeoxyribonucleotides allowed characterization of a fragment internal to the ddl genes encoding D-alanine:D-alanine ligases in Enterococcus columbae, E. durans, E. malodoratus, E. mundtii, E. raffinosus, E. seriolicida, E. solitarius, and E. sulfureus. Phylogenetic analysis of the sequence of the amplification products and of those already obtained from E. aviuni, E. casseliflavus, E. cecorum, E. dispar, E. faecalis, E. faecium, E. flavescens, E. gallinarurm, E. hirae, E. pseudoavium, and E. saccharolvticus yielded an evolutionary tree with a topology similar to that based on 16S rRNA sequences. Partial sequencing of the ddl gene can therefore be used for genotypic identification of Enterococcus spp.     

Identification and composition of the streptococcal and enterococcal flora of tonsils, intestines and faeces of pigs

Streptococcus suis was the most frequent Streptococcus spp. in pig tonsils, followed by the beta-haemolytic porcine 'equisimilis'ecovar of Strep. dysgalactiae. The intestinal streptococcal flora was composed of Strep. bovis, Strep. hyointestinalis and Strep. suis. Many of these intestinal Strep. suis belonged to a beta-glucuronidase-negative biotype which is infrequent in lesions. Nearly half of the strains presumptively identified as Strep. alactolyticus produced acid from lactose. This species was not found in tonsils and intestines but was about equally prevalent as Strep. hyointestinalis in pig faeces and rectal swabs. Other streptococci were rare in this material.
Enterococci were much less frequently identified than streptococci in tonsils and faeces. In intestinal samples Enterococcus faecalis, Ent. faecium, Ent. hirae and Ent. cecorum were most frequently found. In faeces Ent. faecium was the most prevalent enterococcus.
The characteristics of the less well known species Strep. alactolyticus and Strep. hyointestinalis are described in detail, and guidelines for their differentiation from Strep. bovis and Strep. suis given.     

The effect of auditory distractors on song discrimination in male canaries (Serinus canaria)

Male songbirds such as canaries produce complex learned vocalizations that are used in the context of mate attraction and territory defense. Successful mate attraction or territorial defense requires that a bird be able to recognize individuals based on their vocal performance and identify these songs in a noisy background. In order to learn more about how birds are able to solve this problem, we investigated, with a two-alternative choice procedure, the ability of adult male canaries to discriminate between conspecific song segments from two different birds and to maintain this discrimination when conspecific songs are superimposed with a variety of distractors. The results indicate that male canaries have the ability to discriminate, with a high level of accuracy song segments produced by two different conspecific birds. Song discrimination was partially maintained when the stimuli were masked by auditory distractors, but the accuracy of the discrimination progressively declined as a function of the number of masking distractors. The type of distractor used in the experiments (other conspecific songs or different types of artificial white noise) did not markedly affect the rate of deterioration of the song discrimination. These data indicate that adult male canaries have the perceptual abilities to discriminate and selectively attend to one ongoing sound that occurs simultaneously with one or more other sounds. The administration of a noradrenergic neurotoxin did not impair markedly the discrimination learning abilities although the number of subjects tested was too small to allow any firm conclusion. In these conditions, however, the noradrenergic lesion significantly increased the number failures to respond in the discrimination learning task suggesting a role, in canaries, of the noradrenergic system in some attentional processes underlying song learning and processing.     

Photoperiodic response of the hypothalamo-pituitary-gonad axis in male and female canaries,Serinus canaria

Although the gonadal photoperiodic response and its influence upon the song control system in canaries have been extensively studied, photoperiodic regulation of the GnRH system has not been investigated. To examine the relationship between photoperiod and the reproductive neuroendocrine system in male and female canaries, three groups of canaries were exposed to chronic short days (8L:16D; Phsens), acute long days (18L:6D; Phstim) and chronic long days (also 18L:6D; Phrefr) to induce the reproductive states of photosensitivity, photostimulation, and photorefractoriness, respectively. Brain sections were processed for GnRH immunocytochemistry. The canaries in this study did not demonstrate consistent or uniform responses to different photoperiodic treatments. In males, gonad size varied with photoperiod; Phstim males had larger gonads than either the Phsens or Phrefr males. In contrast, there was no difference between groups in female gonad size as a result of photoperiodic treatment. Brain GnRH cell number, cell size, and fiber density were similar in all groups. The results suggest that canaries are not as obligatory photoperiodic as previously thought (or at least not all varieties of domestic canaries are). This could be a result of many years of domestication, the natural history of the species, phylogenetic constraint, or a combination of these factors.     

The Effects of Early Feeding Experience on Long-term Seed Choice by Canaries (Serinus canaria)

Early experience has been found to have long-term effects on behaviour such as social imprinting and song learning. In this paper we investigate whether early experience with particular types of food can lead to long-term feeding preferences in canaries. For 8 wk following the onset of independent foraging, two groups of naive fledgling canaries were reared on different diets. One group had a choice of four seed types, while individuals in the other group received only one type of seed. After this training period, all the birds were given a mixed seed diet for a further 15 wk, and then their preference for the original seeds was tested. All six birds that had been given four seeds during the training period showed the same preference, namely: hemp > niger > millet > linseed. However, all the birds that had been trained on one seed type only, still preferred the seed on which they had been trained. After a further 23 wk on a mixed-seed diet, birds from the restricted early diet group showed no further preference for the seed on which they were trained, and their seed choice at this stage was similar to the birds that had received four seeds. We conclude that early experience can affect food choice in canaries for at least 15 wk, but is subordinate to other influences in the longer term.     

Isospora as an Extraintestinal Parasite of Passerine Birds1

Toxoplasma-like avian parasites inhabiting mononuclear phagocytes have been called Haemogregarina, Toxoplasma. avian Toxoplasma, Atoxoplasma, and Lankesterella by various authors. My attempts to transmit the parasites by bloodsucking mites or by transfer of blood and tissues of infected sparrows and canaries were unsuccessful. However, it was noted that the infection was exacerbated under conditions that favored transmission of coccidiosis: crowding and lack of cleanliness. Oral inoculation of sporulated oocysts of Isospora resulted in death from overwhelming macrophage infection with Toxoplasma-like organisms. Experiments using sparrows and canaries showed that the Isospora species involved was not cross infectious. Further investigations using canaries demonstrated that after oral oocyst inoculation, infection of macrophages spread from the submucosa of the duodenum to the liver. spleen, and lungs. After several generations in the internal organs, asexual multiplication, occured in the intestinal epithelium of the small intestinc. Fecal oocysts first appeared at the end of 9–10 days. Oocysts continued to be passed in the feces for months after infection. This chronicity may be explained by the relatively long life of the macrophages that serve as host cells for the asexual stages as compared to the intestinal epithelium which is the cell type parasitized by conventional coccidia.     

临床分离肠球菌的分布特征及耐药性分析

目的:了解我院临床分离肠球菌的分布特征及耐药现状,为临床合理用药提供依据。方法:对我院2010年1月至2012年12月期间所有临床分离的肠球菌分布情况及药敏结果进行回顾性分析。结果:临床共分离肠球菌242株,粪肠球菌分离率(55.0%)高于屎肠球菌(40.9%),屎肠球菌分离率有增高的趋势。标本来源以尿液(62.9%)、分泌物(10.3%)、血液(6.9%)为主。肠球菌对万古霉素、替考拉宁的敏感性最高,均高于90%。发现耐万古霉素的肠球菌(VRE)7株,其中5株同时耐高浓度的氨基糖苷类抗生素(HLAR);对克林霉素、复方磺胺、阿米卡星、庆大霉素、妥布霉素、苯唑西林耐、头孢西丁耐药率最高,均高于95%。屎肠球菌对青霉素类、氨苄西林、红霉素、呋喃妥因、环丙沙星耐药率均高于粪肠球菌;对四环素、奎努普丁/达福普汀耐药率低于粪肠球菌。结论:肠球菌是临床感染重要病原菌,且具有多重耐药性,屎肠球菌和粪肠球菌耐药水平差异较大,临床应根据药敏结果合理选择抗菌药物。     

Experimental transmission of Sarcocystis from icterid birds to sparrows and canaries by sporocysts from the opossum.

Cowbirds (Molothrus ater) and grackles (Cassidix mexicanus) infected with muscle cysts of Sarcocystis were fed to opposums (Didelphis virginiana) and fecal sporocysts from the latter were given to sparrows (Passer domesticus, Family Ploceidae), canaries (Serinus canarius, Family Fringillidae) and ducks (Anas platyrhynchos, Family Anatidae). Asexual parasites were found in the endothelium of sparrows and canaries but not in ducks. When birds were kept 10 weeks or more after infection, muscle cysts were found grossly and microscopically in the majority of sparrows, and in 1 canary, but not in ducks. Muscle zoites were found in digests of all sparrows and canaries but not in that of ducks. Metrocytes and forms dividing by endodyogeny also were found in the digest. Thus, avian Sarcocystis was transmitted experimentally from 2 genera of 1 family (Icteridae) to 2 different families of passerine intermediate hosts by sporocysts from the definitive host. This is the broadest intermediate host spectrum known for a species of Sarcocystis.     

Effect of artificially increased day length in winter on female domesticated canaries

Three groups of female canaries were given different schedules of increasing day-length between October and December: all groups responded in the same way. Three groups of female canaries were given a 20 hour light/four hour dark schedule at different periods outof the breeding season (October-December, October-January, and January-February).All experimental birds became defeathered and vascular. There was an increase in skin tactile sensitivity in October-December but not in January-February. Nest-building was induced in all months. Only six out of 41 experimental birds laid eggs. Eleven birds which did not lay showed marked incubation behaviour. Discussion centres around the hormonal control of brood patch formation. The possibility that the absence of an effect of photostimulation on sensitivity in January-February is due to shortage of progesterone is considered. These light schedules induced more nest-building than injected oestrogen: no conclusions are yet possible on the hormonal control of next-building.