Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| low-dose d-methionine and n-acetyl-l-cysteine for protection from permanent noise-induced hearing loss in chinchillas. | objective. despite efforts at public health awareness and stringent industrial standards for hearing protection, noise-induced hearing loss (nihl) remains a formidable public health concern. although many antioxidants have proven to be beneficial in the laboratory for prevention of permanent nihl, low-dose combinations of compounds with different biochemical mechanisms of action may allow long-term administration with fewer side effects and equal efficacy. the mixture of d-methionine and n-acety ... | 2011 | 21750343 |
| bacteroides stercorirosoris sp. nov. and bacteroides faecichinchillae sp. nov., isolated from chinchilla (chincilla lanigera) faeces. | strains of gram-negative anaerobic rods were isolated from chinchilla (chinchilla lanigera) faeces, and three strains, st161t, st33 and st37t, were investigated taxonomically. based on the phylogenetic analyses and specific phenotypic characteristics, the three strains belonged to the genus bacteroides. phylogenetic analyses of their 16s rrna gene sequences revealed that strain st161t formed a distinct line of descent, and the highest sequence similarity to st161t was found with strain st33 (98. ... | 2011 | 21724955 |
| chinchilla laniger can be used as an experimental model for taenia solium taeniasis. | chinchilla laniger has been reported as an experimental definitive host for taenia solium; however no information about its suitability and yield of gravid tapeworm proglottids containing viable and infective eggs has been published. in total 55 outbred female chinchillas were infected with 4 cysticerci each; hosts were immunodeppressed with 6 or 8mg of methyl-prednisolone acetate every 14days starting the day of infection and their discomfort was followed. kinetics of coproantigen elisa or expe ... | 2011 | 21723412 |
| physiological assessment of active middle ear implant coupling to the round window in chinchilla lanigera. | objective. to study the effects of various active middle ear implant loading parameters on round window stimulation in an animal model. study design. physiological measurements of the cochlear microphonic and stapes velocity were made from active middle ear implant-generated sinusoidal stimuli with controlled changes in loading parameters. setting. prospective study at an academic research institution. subjects and methods. cochlear microphonic and stapes velocities (h(ev)) were measured in 6 st ... | 2011 | 21593462 |
| genotyping of potentially zoonotic giardia duodenalis from exotic and wild animals kept in captivity in brazil. | we have studied the variability of glutamate dehydrogenase (gdh) and small subunit ribosomal (ssu) rrna coding genes of giardia species in fecal samples isolated from wild and exotic animals in brazil, and compared with homologous sequences of isolates from human and domestic animals characterized in previous studies. cysts of giardia duodenalis were obtained from feces of naturally infected monkeys (alouatta fusca) (n=20), chinchillas (chinchilla lanigera) (n=3), ostriches (struthio camelus) (n ... | 2011 | 21530084 |
| virtual labyrinth model of vestibular afferent excitation via implanted electrodes: validation and application to design of a multichannel vestibular prosthesis. | to facilitate design of a multichannel vestibular prosthesis that can restore sensation to individuals with bilateral loss of vestibular hair cell function, we created a virtual labyrinth model. model geometry was generated through 3-dimensional (3d) reconstruction of micromri and microct scans of normal chinchillas (chinchilla lanigera) acquired with 30-48 ++m and 12 ++m voxels, respectively. virtual electrodes were positioned based on anatomic landmarks, and the extracellular potential field d ... | 2011 | 21380738 |
| mixed giardia duodenalis assemblage a, b, c and e infections in pet chinchillas (chinchilla lanigera) in flanders (belgium). | worldwide there is an increasing trend to keep exotic animals as pets. in contrast to domestic animals, few studies have addressed the importance of infectious diseases of these exotic animals harbor. chinchillas are host to giardia, but prevalence studies are scarce. moreover, little is known about their role as a zoonotic reservoir for giardia. therefore, the objective of the present study was (1) to study the occurrence of giardia in pet chinchillas, (2) to identify risk factors and (3) to de ... | 2010 | 21145658 |
| prevalence and analysis of pseudomonas aeruginosa in chinchillas. | chinchillas (chinchilla laniger) are popular as pets and are often used as laboratory animals for various studies. pseudomonas aeruginosa is a major infectious agent that causes otitis media, pneumonia, septicaemia enteritis, and sudden death in chinchillas. this bacterium is also a leading cause of nosocomial infections in humans. to prevent propagation of p. aeruginosa infection among humans and animals, detailed characteristics of the isolates, including antibiotic susceptibility and genetic ... | 2010 | 21083906 |
| sound pressure transformations by the head and pinnae of the adult chinchilla (chinchilla lanigera). | there are three main cues to sound location: the interaural differences in time (itd) and level (ild) as well as the monaural spectral shape cues. these cues are generated by the spatial- and frequency-dependent filtering of propagating sound waves by the head and external ears. although the chinchilla has been used for decades to study the anatomy, physiology, and psychophysics of audition, including binaural and spatial hearing, little is actually known about the sound pressure transformations ... | 2010 | 20971180 |
| concurrent development of the head and pinnae and the acoustical cues to sound location in a precocious species, the chinchilla (chinchilla lanigera). | sounds are filtered in a spatial- and frequency-dependent manner by the head and pinna giving rise to the acoustical cues to sound source location. these spectral and temporal transformations are dependent on the physical dimensions of the head and pinna. therefore, the magnitudes of binaural sound location cues-the interaural time (itd) and level (ild) differences-are hypothesized to systematically increase while the lower frequency limit of substantial ild production is expected to decrease du ... | 2010 | 20957506 |
| reference values for selected ophthalmic diagnostic tests and clinical characteristics of chinchilla eyes (chinchilla lanigera). | to establish reference values for the schirmer tear test i (stt i), the phenol red thread tear test (prtt), the intraocular pressure (iop) with rebound tonometry, to determine the corneal sensitivity for healthy chinchillas, and to describe clinical aspects of normal chinchilla eyes. | 2010 | 20840088 |
| adaptation of the vestibulo-ocular reflex for forward-eyed foveate vision. | to maintain visual fixation on a distant target during head rotation, the angular vestibulo-ocular reflex (avor) should rotate the eyes at the same speed as the head and in exactly the opposite direction. however, in primates for which the 3-dimensional (3d) avor has been extensively characterised (humans and squirrel monkeys (saimiri sciureus)), the avor response to roll head rotation about the naso-occipital axis is lower than that elicited by yaw and pitch, causing errors in avor magnitude an ... | 2010 | 20724359 |
| the ovarian and uterine arteries in the chinchilla (chinchilla lanigera). | the purpose of this study was to describe arteries supplying the ovaries and uterus in the chinchilla. five healthy adult female chinchillas were used. in order to reveal the arterial network by dissecting under a stereoscopic microscope, latex coloured with red ink was injected through the common carotid artery. the ovaries of the chinchilla are supplied by the arteriae ovaricae which formed end-to-end anastomoses with the cranial termination of the arteria uterina. soon after leaving the aorta ... | 2010 | 20649156 |
| mapping the anatomy of respiratory syncytial virus infection of the upper airways in chinchillas (chinchilla lanigera). | although most viral infections of the upper respiratory tract can predispose to bacterial otitis media, human respiratory syncytial virus (hrsv) is the predominant viral copathogen of this highly prevalent pediatric polymicrobial disease. rigorous study of the specific mechanisms by which hrsv predisposes to otitis media has been hindered by lack of a relevant animal model. we recently reported that the chinchilla, the preferred rodent host for studying otitis media, is semipermissive for upper- ... | 2010 | 20579438 |
| bacteroides chinchillae sp. nov. and bacteroides rodentium sp. nov., isolated from chinchilla (chinchilla lanigera) faeces. | gram-negative anaerobic rods were isolated from chinchilla (chinchilla lanigera) faeces and three strains, st170(t), st180 and st28(t), were investigated taxonomically. on the basis of phylogenetic analyses and specific phenotypic characteristics, the three strains belonged to the genus bacteroides. phylogenetic analysis of their 16s rrna gene sequences revealed that strains st170(t) and st180 formed a single cluster and a distinct line of descent. strain st170(t) exhibited 99.7 % 16s rrna gene ... | 2011 | 20495039 |
| undifferentiated carcinoma of the salivary gland in a chinchilla (chinchilla lanigera). | a 12-year-old chinchilla (chinchilla lanigera) developed a slow-growing, soft, fluctuating, nonpainful mass on the ventral neck with focally extensive alopecia over a period of approximately 8 months. on postmortem examination, an extensive, multilobulated, cystic, neoplastic mass extended subcutaneously over the ventral and lateral neck with metastatic spread to submandibular lymph nodes, spleen, liver, and lungs. neoplastic cells were strongly positive for vimentin and pan-cytokeratin but were ... | 2010 | 20093708 |
| postnatal development of neuronal responses to frequency-modulated tones in chinchilla auditory cortex. | responses to cortical neurons to frequency-modulated (fm) stimuli have been described in various adult animal models. here, we ask whether fm coding at the cortical level is innate or if it is influenced by postnatal environmental experience. we report on the fm response properties of neurons in core auditory cortex of newborn (p3), 1-month-old (p28) and adult (>1-year-old) anesthetized chinchillas (chinchilla laniger). upward and downward linear fm sweeps spanning frequencies from 0.1 to 20 khz ... | 2010 | 19874805 |
| chinchilla as a robust, reproducible and polymicrobial model of otitis media and its prevention. | there is compelling evidence that many infectious diseases of humans are caused by more than one microorganism. multiple diverse in vitro systems have been used to study these complex diseases, and although the data generated have contributed greatly to our understanding of diseases of mixed microbial etiology, having rigorous, reproducible and relevant animal models of human diseases are essential for the development of novel methods to treat or prevent them. all animal models have inherent lim ... | 2009 | 19627188 |
| responses of neurons in chinchilla auditory cortex to frequency-modulated tones. | frequency-modulated (fm) stimuli have been used to explore the behavior of neurons in the auditory cortex of several animal models; however, the properties of fm-sensitive auditory cortical neurons in the chinchilla are still unknown. single-unit responses to fm stimulation were obtained from the auditory cortex of anesthetized adult chinchillas (chinchilla laniger). upward and downward linear fm sweeps spanning frequencies from 0.1 to 20 khz were presented at speeds of 0.05 to 0.82 khz/ms. resu ... | 2009 | 19211659 |
| an outbreak of acute aflatoxicosis on a chinchilla (chinchilla lanigera) farm in argentina. | chinchillas (chinehilla lanigera) are known to be very sensitive to aflatoxins, and often a large number of animals die if toxicosis occurs. an outbreak of acute aflatoxicosis on a chinchilla farm in argentina is described in the present study. a commercial feed suspected of causing the death of 200 animals was sampled. livers from 9 dead chinchillas were analyzed for their macroscopic and microscopic characteristics via necropsy and histopathology. aflatoxins b(1), b(2), g(1), and g(2) were det ... | 2008 | 18987247 |
| hyperthyroidism in connection with suspected diabetes mellitus in a chinchilla (chinchilla laniger). | 2008 | 18849579 | |
| slow increase of sertoli cell efficiency and daily sperm production causes delayed establishment of full sexual maturity in the rodent chinchilla lanigera. | puberty in the male andean rodent chinchilla lanigera occurred approximately 3 mo after birth, whereas full sexual maturity was established much later. the objective of the present study was to investigate testis function in postpubertal chinchillas, with an emphasis on the estimation of seminiferous epithelium cycle length (n=6) and sertoli cell (sc) and spermatogenic efficiencies (n=26). samples of testes were collected between may and november. each spermatogenic cycle lasted 10.2d and the to ... | 2009 | 18834623 |
| systematization, distribution and territory of the middle cerebral artery on the brain surface in chinchilla (chinchilla lanigera). | the aim of the present study was to analyse thirty chinchilla (chinchilla lanigera) brains, injected with latex, and to systematize and describe the distribution and the vascularization territories of the middle cerebral artery. this long vessel, after it has originated from the terminal branch of the basilar artery, formed the following collateral branches: rostral, caudal and striated (perforating) central branches. after crossing the lateral rhinal sulcus, the middle cerebral artery emitted a ... | 2009 | 18786159 |
| postnatal sertoli and leydig cell proliferation and the establishment of puberty and sexual maturity in chinchilla lanigera (rodentia, chinchillidae). | the chilean chinchilla (chinchilla lanigera) is threatened in its natural habitat and there is very little information concerning the reproductive biology of this species. our main objectives were to investigate the postnatal testis development in this rodent, with emphasis on sertoli and leydig cell proliferation and the establishment of puberty and sexual maturity. forty-four animals from one day to 30 months of age had their testis and epididymis prepared (time of collection for animals from ... | 2008 | 18671914 |
| lumbar osteosarcoma in a chinchilla (chinchilla laniger). | an 11-year-old male chinchilla was presented for investigation of progressive weight loss, apathy, anorexia, changes in faecal quality and alopecia on the tip of the tail. on clinical examination, a stiffness of the back legs was noted. abdominal palpation revealed a hard immobile, irregular structure in the region of the last lumbar vertebrae. subsequent radiography and ultrasonography suggested the presence of neoplasia. the following day the chinchilla was showing hindlimb paralysis, and ther ... | 2008 | 18631221 |
| strain-specific virulence phenotypes of streptococcus pneumoniae assessed using the chinchilla laniger model of otitis media. | streptococcus pneumoniae [sp] infection is associated with local and systemic disease. our current understanding of the differential contributions of genetic strain variation, serotype, and host response to disease phenotype is incomplete. using the chinchilla model of otitis media [om] we investigated the disease phenotype generated by the laboratory strain tigr4 and each of thirteen clinical strains (bs68-75, bs290, bs291, bs293, bs436 and bs437); eleven of the thirteen strains have been genom ... | 2008 | 18398481 |
| pitch perception in chinchillas (chinchilla laniger): stimulus generalization using rippled noise. | rippled noises evoke the perception of pitch in human listeners. infinitely iterated rippled noise (iirn) is generated when wideband noise (wbn) is delayed, attenuated, and added to the original wbn through either a positive (+) or a negative (-) feedback loop. the pitch of iirn[+] is matched to the reciprocal of the delay, whereas the pitch of iirn[-] for the same delay is an octave lower. chinchillas (chinchilla laniger) were trained to discriminate iirn[+] with a 4-ms delay from iirn[+] with ... | 2007 | 18085927 |
| functional activity of frozen thawed chinchilla lanigera spermatozoa cryopreserved with glycerol or ethylene glycol. | the cryopreservation of spermatozoa constitutes a valuable tool for the captive breeding management of valuable and/or threatened species. chinchilla lanigera is a species almost extinct in the wild, and the domestic counterpart has one of the most valuable pelts in the world. the objectives of this study were to: (i) compare the functional activity of post-thawed chinchilla spermatozoa cryopreserved at -196 degrees c either with glycerol (g) or ethylene glycol (eg) as cryoprotectants (1 m final ... | 2008 | 18042209 |
| the right coronary artery is absent in the chinchilla (chinchilla lanigera). | a total of 10 adult, healthy, male chinchillas (chinchilla lanigera) were used to investigate the origin, course, and termination of the coronary arteries. coloured latex was injected into the carotid arteries following conventional anatomical applications. in all the chinchillas examined, the left coronary artery was the single coronary artery. the right coronary artery was missing. additionally, a small vessel originating from the cranial border of the aorta was observed in one chinchilla. the ... | 2008 | 18005371 |
| subgross and macroscopic investigation of blood vessels originating from aortic arch in the chinchilla (chinchilla lanigera). | a total of 10 adult, healthy, male chinchilla (chinchilla lanigera) were used to investigate the vessels originating from aortic arch. coloured latex was injected into the carotid arteries following conventional anatomical applications in all the chinchillas examined. the brachiocephalic trunk and the left subclavian artery arose from the aortic arch at the level of the second intercostal region in the thoracic cavity. the right and left subclavian arteries detached branches at the level of firs ... | 2008 | 18005370 |
| first description of natural echinococcus multilocularis infections in chinchilla (chinchilla laniger) and prevost's squirrel (callosciurus prevostii borneoensis). | this report describes for the first time the occurrence of alveolar echinococcosis in two exotic rodent species in europe. a pet chinchilla (chinchilla laniger) was euthanized due to a painful enlargement of the abdominal cavity, and a prevost's squirrel (callosciurus prevostii borneoensis) was found dead in the enclosure of a zoo. at necropsy, extended liver lesions consisting of small vesicles and cysts were observed in the livers of both animals. histological examination revealed that these c ... | 2007 | 17768640 |
| gross morphological features of plexus brachialis in the chinchilla (chinchilla lanigera). | this study documents the detailed features of the morphological structure and the innervation areas of the plexus brachialis in the chinchilla (chinchilla lanigera). the animals (5 female and 5 male) were euthanased with ketamine hydrocloride and xylazine hydrocloride combination, 60 mg/kg and 6 mg/kg, respectively. skin, muscles and nerves were dissected under a stereo-microscope. the brachial plexus of the chinchilla is formed by rami ventrales of c5-c8, t1 and t2, and possesses a single trunc ... | 2007 | 17665761 |
| an outbreak of toxoplasmosis in an ontario chinchilla herd. | an outbreak of toxoplasmosis which killed 44 of a herd of 56 chinchillas and produced 4 abortions with the loss of a total of five fetuses is reported. a wild mouse thought to be the house mouse (mus musculus), caught in a trap in the basement housing the chinchillas, was found to be infected with toxoplasma gondii. the suggestion is made of the existence of a reservoir of infestation in wildlife with wild rodents implicated in this case as possible transmitters of the disease. the post mortem f ... | 1964 | 17649492 |
| virulence phenotypes of low-passage clinical isolates of nontypeable haemophilus influenzae assessed using the chinchilla laniger model of otitis media. | the nontypeable haemophilus influenzae (nthi) are associated with a spectrum of respiratory mucosal infections including: acute otitis media (aom); chronic otitis media with effusion (come); otorrhea; locally invasive diseases such as mastoiditis; as well as a range of systemic disease states, suggesting a wide range of virulence phenotypes. genomic studies have demonstrated that each clinical strain contains a unique genic distribution from a population-based supragenome, the distributed genome ... | 2007 | 17570853 |
| time-related changes in functional activity and capacitation of chinchilla (chinchilla lanigera) spermatozoa during in vitro incubation. | the application of assisted breeding programs for chinchilla, an endangered species, requires detailed knowledge about their gamete physiology. main purposes of the present study were to examine the time-related changes during 8h in vitro incubation in parameters that reflect chinchilla sperm functional activity (including sperm motility, viability, membrane and acrosome integrity), and to determine the incubation time required for achieving in vitro sperm capacitation, evaluated through the qua ... | 2007 | 17395408 |
| hydrogen peroxide ototoxicity in unblocking ventilation tubes: a chinchilla pilot study. | some clinicians use hydrogen peroxide (h2o2) to clear the lumen of ventilation tubes that become blocked postoperatively. the ototoxicity associated with h2o2 has been controversial. | 2007 | 17275542 |
| taenia coenurus in the orbit of a chinchilla. | a 4-year old, male intact, captive-bred chinchilla (chinchilla lanigera) was presented due to progressive exophthalmos of the right eye over a 5-month period. ophthalmic examination revealed exophthalmos with dorsal displacement of the right globe. retropulsion was decreased and a fluctuant, subcutaneous mass could be palpated posterior and dorsal to the central aspect of the zygomatic bone. transdermal ultrasonography revealed a fluid-filled mass consistent with a cyst located within the ventra ... | 2007 | 17204129 |
| phosphorylcholine decreases early inflammation and promotes the establishment of stable biofilm communities of nontypeable haemophilus influenzae strain 86-028np in a chinchilla model of otitis media. | nontypeable haemophilus influenzae (nthi) is a leading causative agent of otitis media. much of the inflammation occurring during nthi disease is initiated by lipooligosaccharides (los) on the bacterial surface. phosphorylcholine (pcho) is added to some los forms in a phase-variable manner, and these pcho(+) variants predominate in vivo. thus, we asked whether this modification confers some advantage during infection. virulence of an otitis media isolate (nthi strain 86-028np) was compared with ... | 2007 | 17130253 |
| noninvasive monitoring of ovarian endocrine activity in the chinchilla (chinchilla lanigera). | reproductive endocrinology information is limited for chinchilla lanigera, a south american species characterized by extremely long gestation and estrus cycle compared with others rodents. this study was designed to validate a non-invasive technique for monitoring ovarian endocrine activity. animals were exposed indoors to natural photoperiod (31 degrees s-64 degrees w, argentina); temperature range: 17-26 degrees c, with food and water ad libitum. radiolabelled infusion (n=4): (3)h-estradiol (( ... | 2007 | 17094993 |
| structures that contribute to middle-ear admittance in chinchilla. | we describe measurements of middle-ear input admittance in chinchillas (chinchilla lanigera) before and after various manipulations that define the contributions of different middle-ear components to function. the chinchilla's middle-ear air spaces have a large effect on the low-frequency compliance of the middle ear, and removing the influences of these spaces reveals a highly admittant tympanic membrane and ossicular chain. measurements of the admittance of the air spaces reveal that the high- ... | 2006 | 16944166 |
| geometry of the semicircular canals of the chinchilla (chinchilla laniger). | the orientations of the semicircular canals determines the response of the canals to head rotations and, in turn, the brain's ability to interpret those motions. the geometry of chinchillas' semicircular canals has never been reported. volumetric representations of three chinchilla skulls were generated using a microct scanner. the centroids of each semicircular canal lumen were identified as they passed through the image slices and were regressed to a plane. unit vectors normal to the plane rep ... | 2006 | 16439079 |
| thyroparathyroidectomy procedures and thyroxine levels in the chinchilla. | thyroid and embedded parathyroid glands were surgically removed (thyroparathyroidectomized) from adult chinchillas (chinchilla laniger) to create an animal model of hypothyroidism. thyroxine (t4) levels were measured at the time of surgery and one or two times after surgery from 10 thyroparathyroidectomized chinchillas and five sham controls to establish baseline serum t4 levels and to assess the degree and duration of hypothyroidism in this animal model. baseline t4 levels ranged from 3.4 to 6. ... | 2005 | 16370577 |
| year-round testicular volume and semen quality evaluations in captive chinchilla lanigera. | in mammals, reproductive performance is usually associated with seasons. chinchilla lanigera, an endemic south american rodent, reproduces throughout the year in captivity but its seasonal breeding pattern is not fully understood. the present study was designed to evaluate (bi-weekly) over 1 year: (1) testicular volume variations and (2) seminal volume, sperm concentration and functional activity changes. five animals were studied; they were individually housed indoors (22.2 +/- 1.0 degrees c) u ... | 2005 | 16257602 |
| tone responses in core versus belt auditory cortex in the developing chinchilla. | single-unit responses to tone pip stimuli were isolated from numerous microelectrode penetrations of core primary auditory cortex (ai) and a dorsocaudal (dc) belt region in the ketamine-anesthetized chinchilla (laniger). results are reported at postnatal day 3 (p3), p15, p30, and from adult animals. the ai core could be distinguished from the dc belt on the basis of its strict tonotopic organization, evident in all chinchillas studied (including the youngest). averaged by age group and compared ... | 2005 | 16175561 |
| assessment of urine and fecal testosterone metabolite excretion in chinchilla lanigera males. | endemic chinchilla (chinchilla spp.) populations are nearly extinct in the wild (south america). in captive animals (chinchilla lanigera and c. brevicaudata), reproduction is characterized by poor fertility and limited by seasonal breeding patterns. techniques applied for studying male reproductive physiology in these species are often invasive and stressful (i.e. repeated blood sampling for sexual steroids analysis). to evaluate endocrine testicular function, the present experiments were design ... | 2005 | 15766811 |
| number and nuclear localisation of nucleoli in mammalian spermatocytes. | in seven mammalian species, including man, the position and number of nucleoli in pachytene spermatocyte nuclei were studied from electron microscope (em) nuclear sections or bivalent microspreads. the number and position of the nucleolar organiser regions (nors) in mitotic and meiotic chromosomes were also analysed, using silver staining techniques and in situ hybridisation protocols. the general organisation of pachytene spermatocyte nucleoli was almost the same, with only minor morphological ... | 2004 | 15521420 |
| electroejaculation in the chinchilla (chinchilla lanigera): effects of anesthesia on seminal characteristics. | repetitive electroejaculation is probably extremely stressful in conscious animals and could adversely affect fertility. the present study was designed to (a) evaluate the effects of anesthesia (40 mg ketamine/kg body weight, i.m.) on a method of electroejaculation used previously in conscious chinchillas (chinchilla lanigera), and (b) determine the quality of the electroejaculated semen obtained under anesthesia. in experiment 1 (8 animals), a 4 x 4 latin square design was used to study the eff ... | 2005 | 15500845 |
| tone frequency maps and receptive fields in the developing chinchilla auditory cortex. | single-unit responses to tone pip stimuli were isolated from numerous microelectrode penetrations of auditory cortex (under ketamine anesthesia) in the developing chinchilla (laniger), a precocious mammal. results are reported at postnatal day 3 (p3), p15, and p30, and from adult animals. hearing sensitivity and spike firing rates were mature in the youngest group. the topographic representation of sound frequency (tonotopic map) in primary and secondary auditory cortex was also well ordered and ... | 2005 | 15342716 |
| anaesthesia with midazolam/medetomidine/fentanyl in chinchillas (chinchilla lanigera) compared to anaesthesia with xylazine/ketamine and medetomidine/ketamine. | we studied four different drug regimes for anaesthetic management in chinchillas and evaluated and compared their cardiovascular and respiratory effects. in this randomized, cross-over experimental study, seven adult chinchillas, five females, two males [515 +/- 70 (sd) g] were randomly assigned to one of the following groups: group 1 [midazolam, medetomidine and fentanyl (mmf), flumazenil, atipamezole and naloxone (fan); mmf-fan] received 1.0 mg/kg midazolam, 0.05 mg/kg medetomidine and 0.02 mg ... | 2004 | 15315707 |
| isolation of listeria ivanovii from a septicaemic chinchilla (chinchilla lanigera). | 2004 | 15233458 | |
| identification and characterization of a mucosal antimicrobial peptide expressed by the chinchilla (chinchilla lanigera) airway. | cationic antimicrobial peptides (aps) are produced at mucosal surfaces and play a key role as a first line of defense against infection. to understand how aps might impact disease progression in otitis media (om), our goal was to identify and characterize aps expressed by the epithelium lining the uppermost airway of the chinchilla, the established rodent host for the study of the bacterial-viral pathogenesis in om. using a molecular approach, we cloned a cdna encoding a homolog of human beta-de ... | 2004 | 14996845 |
| a non-invasive method for assessing adrenal activity in the chinchilla (chinchilla lanigera). | the chinchilla is a rodent that was once abundant in the central andes of south america. excessive hunting for fur greatly reduced its distribution at the beginning of the twentieth century, and today chinchilla species are nearly extinct in the wild. although protected, wild populations of chinchilla are still declining. in general, this species has received little research attention and its biology is poorly understood. improvements in captive breeding, husbandry, and genetic management are ne ... | 2004 | 14981780 |
| specific distribution pattern of nerve fibers containing catecholamine-synthesizing enzymes, neuropeptide y (npy) and c-terminal flanking peptide of npy (cpon) in the pineal gland of the chinchilla (chinchilla laniger)--an immunohistochemical study. | the sympathetic nerve fibers originating from the superior cervical ganglia and supplying the pineal gland play the most important role in the control of the pineal activity in mammals. npy and cpon are also present in the majority of the pinealopetal sympathetic neurons. in this study, immunohistochemical techniques were used to demonstrate the existence and coexistence of tyrosine hydroxylase (th), dopamine beta-hydroxylase (dbetah) as well as npy and cpon in the nerve fibers supplying the chi ... | 2003 | 14677758 |
| reduced severity of middle ear infection caused by nontypeable haemophilus influenzae lacking the hemoglobin/hemoglobin-haptoglobin binding proteins (hgp) in a chinchilla model of otitis media. | since haemophilus influenzae lacks enzymes necessary for synthesis of the porphyrin ring, it has an absolute growth requirement for a porphyrin source. this requirement can be satisfied in vitro by hemoglobin and hemoglobin complexed to haptoglobin. the products of the hgp genes mediate the utilization of heme from hemoglobin-haptoglobin. these genes are also involved in the use of heme from hemoglobin, although additional gene products independently mediate the acquisition of heme from this sub ... | 2004 | 14643637 |
| [the morphological blood picture of chinchilla velligera (prell 1934)]. | 1959 | 14411607 | |
| the demonstration of a sexual dimorphism in liver cells of the rodent chinchilla laniger. | 1959 | 14403042 | |
| experimental leptospirosis in the chinchilla (chinchilla laniger). | 1961 | 13778743 | |
| the susceptibility of the chinchilla (chinchilla laniger) to leptospira pomona. | 1958 | 13549324 | |
| outbreak of salmonella enteritidis and isolation of salmonella sofia in chinchillas (chinchilla laniger). | 2003 | 12825706 | |
| a comparative study on cardiac ganglia in midday gerbil, egyptian spiny mouse, chinchilla laniger and pigeon. | using the thiocholine method and histological techniques, the topography and morphology of cardiac ganglia in midday gerbil, egyptian spiny mouse, chinchilla laniger and pigeon were studied. the results demonstrated that cardiac ganglia in all investigated species are embedded in epicardial fat. they formed plexo-ganglionic structures. each of them composed of many ganglia (from seven up to 36) different in size and shape, and interconnected by fascicles of nerve fibres. comparative analysis sho ... | 2003 | 12823098 |
| spontaneous human herpes virus type 1 infection in a chinchilla (chinchilla lanigera f. dom.). | a 1-year-old male chinchilla with a 2-week history of conjunctivitis suffered subsequently from neurological signs comprising seizures, disorientation, recumbency and apathy. after 3 weeks of progressive central nervous disease the animal was killed in view of the poor prognosis. a non-suppurative meningitis and polioencephalitis with neuronal necrosis and intranuclear inclusion bodies were observed at necropsy and by light microscopy. the brain stem and cerebral cortices were most severely affe ... | 2002 | 12410390 |
| hemoglobin affinity in andean rodents. | blood hemoglobin oxygen affinity (p50) was measured in three andean species and in the laboratory rat (control), all raised near sea level. chinchilla lanigera (molina, 1792) has an altitudinal habitat range from low andean slopes up to 3000 m., while chinchilla brevicaudata (waterhouse, 1848) has an altitudinal range from 3000 to 5000 m. the laboratory type guinea pig, wild type guinea pig (cavia porcellus), (waterhouse, 1748), and laboratory rat (rattus norvegicus) were also raised at sea leve ... | 2002 | 12125201 |
| temporal and spatial coding of periodicity information in the inferior colliculus of awake chinchilla (chinchilla laniger). | amplitude modulation responses and onset latencies of multi-unit recordings and evoked potentials were investigated in the central nucleus of inferior colliculus (icc) in the awake chinchilla. nine hundred and one recording sites with best frequencies between 60 and 30 khz showed either phasic (18%), tonic (25%), or phasic-tonic (57%) responses. of 554 sites tested for responses to modulation frequencies 73% were responsive and 57% showed clear preference for a narrow range of modulation frequen ... | 2002 | 12117514 |
| diagnosis of sexual cycle by means of vaginal smear method in the chinchilla (chinchilla lanigera). | an investigation was made as to whether the sexual cycle and pregnancy can be determined by means of vaginal smear in chinchillas. this study represents the first attempt to record changes which occur in the pattern of exfoliated cells in chinchilla's vaginal smear during anoestrus, proestrus, oestrus, metoestrus and pregnancy. fifteen female chinchillas aged from 8 months to 3 years and bred through harem breeding method were used. the major change during proestrus was an increase in the propor ... | 2002 | 11831739 |
| storage of chinchilla lanigera semen at 4 degrees c for 24 or 72 h with two different cryoprotectants. | the objectives of this study were to: (a) test the functional activity of chinchilla lanigera spermatozoa suspended in either glycerol or ethylene glycol, cooled to 4 degrees c, and stored for 24 or 72 h and (b) investigate, after these cooling periods, the effects of incubating sperm at 37 degrees c (for 4 h) upon sperm functional activity. the ejaculate was mixed with the cryoprotectant medium (at 1 m final concentration) and cooled to 4 degrees c. after warming, sperm motility, sperm viabilit ... | 2001 | 11748938 |
| arterial blood supply to the auditory cortex of the chinchilla. | utilizing optical imaging we identified and named the arteries that supply the primary auditory cortex in the chinchilla (chinchilla laniger). the primary auditory cortex is located 2-3 mm caudal to the medial cerebral artery and is supplied by it. using corrosion casts and scanning electron microscopy we visualized the capillary networks in the auditory cortex and found regional variations in the densities of the capillary bed. we hypothesize that the uneven capillary densities observed in the ... | 2001 | 11718249 |
| frenkelia microti infection in a chinchilla (chinchilla laniger) in the united states. | a frenkelia microti tissue cyst was found in the brain of a chinchilla (chinchilla laniger) used for biomedical research. this is the first report of frenkelia infection in this animal in the united states. | 2000 | 11128498 |
| activity of chinchilla laniger spermatozoa collected by electroejaculation and cryopreserved. | because reproductive studies and the application of assisted reproductive techniques are relevant issues for an endangered species such as chinchila laniger, the availability of a source of viable spermatozoa becomes of utmost importance. in this paper, we evaluate several functional parameters (motility, viability, response to hypoosmotic swelling test and acrosomal integrity) of fresh or frozen-thawed spermatozoa. electro-ejaculation trials (50-cyc/sec sinusoidal wave was applied for 5 of ever ... | 1998 | 10734438 |
| three distinct auditory areas of cortex (ai, aii, and aaf) defined by optical imaging of intrinsic signals. | using pure-tone sound stimulation, three separate auditory areas are revealed by optical imaging of intrinsic signals in the temporal cortex of the chinchilla (chinchilla laniger). these areas correlate with primary auditory cortex (ai) and two secondary areas, aii and the anterior auditory field (aaf). we have distinguished ai on the basis of concurrent single-unit electrophysiological recording; neurons within the ai intrinsic signal region have short (<15 ms) onset-response latencies compared ... | 2000 | 10725186 |
| morphologic changes in the inner ear of chinchilla laniger after middle ear administration of gentamicin in a sustained-release vehicle. | the use of transtympanic gentamicin has become a popular method of treating meniere's disease; nevertheless, many questions still remain regarding this therapy. until investigators can control the exact amount of medicine that is administered to the ear and have an understanding of the kinetics of gentamicin, therapy will continue to rely on empirical data. previously we described the use of a fibrin-based sustained-release vehicle impregnated with gentamicin in the middle ears of chinchillas. w ... | 1999 | 10229587 |
| use of computed tomography to investigate cheek tooth abnormalities in chinchillas (chinchilla laniger) | computerised tomographic scanning was used to investigate tooth structure in chinchillas (chinchilla laniger), both cheek tooth crown and root abnormalities being common in this species. this paper describes a common form of dental disease affecting species with continuously growing teeth, with particular reference to the chinchilla, and confirms the potential role of computed tomography (ct) in its early diagnosis. ct imaging is compared with previously available methods of investigation which ... | 1998 | 9741874 |
| functional activity of epididymal chinchilla laniger spermatozoa cryopreserved in different extenders. | chinchilla laniger is an endangered species and improved cryopreservation of spermatozoa would constitute a significant advance in the development of assisted reproductive techniques in this species. the functional activity of epididymal spermatozoa from adult males was studied immediately after extrusion and after 24 hours incubation, and the ability of five extenders to protect these gametes during cryopreservation was determined. a decrease in sperm motility, viability, acrosome intact cells ... | 1998 | 9690610 |
| comparative evaluation of culture and pcr for the detection and determination of persistence of bacterial strains and dnas in the chinchilla laniger model of otitis media. | this study was designed to determine the persistence of culturable bacteria versus dna in the presence of a middle ear effusion in a chinchilla model of otitis media. cohorts of animals were either infected with an ampicillin-resistant haemophilus influenzae strain or injected with a tripartite inoculum consisting of freeze-thawed streptococcus pneumoniae; pasteurized moraxella catarrhalis; and dna from h influenzae. the h influenzae-infected animals displayed culture positivity and polymerase c ... | 1998 | 9635461 |
| caries and odontoclastic resorptive lesions in a chinchilla (chinchilla lanigera). | 1997 | 9347624 | |
| age-related decline of auditory function in the chinchilla (chinchilla laniger). | the aim of this study was to examine the functional consequences of aging in the chinchilla, a rodent with a relatively long life span and a range of hearing similar to that of humans. subjects were 21 chinchillas aged 10-15 years, and 23 young controls. thresholds were determined from auditory evoked potentials (evps), and outer hair cell (ohc) functioning was assessed by measuring 2f1-f2 distortion product otoacoustic emissions (dpoaes). six cochleas from 11-12-year-old animals were examined f ... | 1997 | 9307317 |
| digital-image analysis of the brain-base arteries in chinchilla, chinchilla laniger (molina). | this paper attempts to quantitatively characterize the cerebral arterial circle in the chinchilla using a computerized image-analysis system. the sole source of the blood supply to the brain in this animal is the vertebral arteries and the basilar arteries. it was found that the diameter and volume of the basilar artery were over twofold larger than those of cerebral-circle arteries. the total length of the cerebral-circle arteries was approximately two times greater than the length of the basil ... | 1996 | 8766405 |
| pseudomonas aeruginosa infection in a chinchilla lanigera. | this report describes a case of pseudomonas aeruginosa infection in a chinchilla. the affected animal displayed a variety of clinical signs including genital swelling, conjunctivitis, anorexia, weight loss, corneal and oral ulcerations and, most unusually, intradermal pustules which developed 8 days after recovery from the initial illness. the occurrence of these pustules has not been documented previously. | 1993 | 8501894 |
| fine structure of the vomeronasal organ in the chinchilla (chinchilla laniger). | fine structure of the vomeronasal organ (vno) was examined in the chinchilla (chinchilla laniger) from a viewpoint of comparative anatomy. the vno of chinchilla was a pair of tubular structure, about 6mm in length, and situated bilaterally along the base of the nasal septum. the vno was encircled rostrally by the vomeronasal cartilage, but caudally by a bony capsule. the vno communicated with the nasal cavity via a small pore at its rostral end, while it ended blindly at its caudal end. its lume ... | 1994 | 7805792 |
| elevation of auditory thresholds by spontaneous cochlear oscillations. | the inner ear sometimes acts as a robust sound generator, continuously broadcasting sounds (spontaneous otoacoustic emissions) which can be intense enough to be heard by other individuals standing nearby. paradoxically, most individuals are unaware of the sounds generated within their ears. two hypotheses could explain this paradox: (1) the spontaneous emissions may not be transmitted to the central nervous system; or (2) the spontaneous emission produces a continuous, high rate of neural activi ... | 1995 | 7791874 |
| clinical ocular findings in a colony of chinchillas (chinchilla laniger). | examination of 14 aged chinchillas revealed a shallow orbit, a rudimentary nictitating membrane, a large cornea, a densely pigmented iris with a vertical slit pupil, and an anangiotic fundus with variable vascularization of the optic disc. mean intraocular pressure was 18.5 /+- 5.75 standard deviation mmhg. bilateral posterior cortical cataracts and asteroid hyalosis were observed in 2 animals. | 1980 | 7464022 |
| ketamine-acepromazine as an anaesthetic agent for chinchillas (chinchilla laniger). | intramuscular injections of ketamine-acepromazine provided satisfactory surgical levels of anaesthesia. induction was smooth. there was a wide margin of safety with no significant side effects, and there were no deaths attributable to anaesthesia. induction time was 4-6 min, duration of surgical anaesthesia was 40-60 min, with complete recovery in 2-5 h. 80 chinchillas were used for this study. | 1981 | 7289581 |
| consumption of food, body weight, perineal colour and levels of progesterone in the serum of cyclic female chinchillas. | venous blood of eight cyclic female chinchillas (chinchilla laniger) was collected twice weekly during all stages of the oestrous cycle and levels of progesterone were determined by radioimmunoassay. consumption of food, body weight and perineal colour were also monitored in 25 cyclic female chinchillas. cyclic trends were significant for feed consumption (p < 0.01), colour of the perineum (p < 0.001) and body weight (p < 0.001). analysis of data used a standardized cycle of 36 days which was ar ... | 1980 | 7191885 |
| [normal bacterial flora of the wild chinchilla lanigera]. | 1982 | 7186674 | |
| experimental otitis media in gerbils and chinchillas with streptococcus pneumoniae, haemophilus influenzae, and other aerobic and anaerobic bacteria. | to ascertain the usefulness of mongolian gerbils as an inbred model for otitis media, 52 mongolian gerbils (meriones unguiculatus, strain mont/tum) were compared with 26 chinchillas (chinchilla laniger) for susceptibility to streptococcus pneumoniae type 3. haemophilus influenzae type b, and a polymicrobic culture including anaerobes (streptococcus intermedius, propionibacterium acnes, staphylococcus epidermidis, and corynebacterium sp.). organisms were inoculated percutaneously into the superio ... | 1982 | 6979517 |
| ultrastructural observation of paracrystalline aggregates of microtubules in anterior pituitary cells of the chinchilla (chinchilla laniger). | unusual paracrystalline aggregates of microtubules which have not been described in any other mammalian species were observed in cultured anterior pituitary cells of normal chinchillas as well as in situ in the pituitary glands of these animals. these aggregates appeared as regularly arranged tubular structures in the longitudinal plane, and as a checkerboard pattern of closely and regularly packed microtubules when examined in transverse section. supplementation with vinblastine, colcemide or c ... | 1980 | 6778615 |
| dimensional analysis and dynamic response characterization of mammalian peripheral vestibular structures. | extensive morphometric measurements were made on the vestibular system of the rabbit ( oryctulagus cuniculus), the gerbil (meriones unguiculatus), the chinchilla (chinchilla laniger ), and the squirrel monkey (saimiri sciureus) from serial sections of temporal bones. additionally, a more limited set of measurements were also completed on the owl monkey (aotus trivirgatus), the capuchin monkey (cebus sp.), the harp seal ( pagophilus groenlandicus erxleben , 1777), and the two-toed sloth ( choloep ... | 1984 | 6609629 |
| seasonal changes in the haematological indices in peripheral blood of chinchilla (chinchilla laniger l.). | changes in nine haematological indices in adult female and male chinchilla were investigated over a period of 18 months. all haematological values were in the same range both for females and males, although seasonal fluctuations were more evident in the females. high levels of the red blood cells count (rbc), haemoglobin concentration (hb), mean cell haemoglobin (mch) and mean corpuscular haemoglobin concentration (mchc) during the winter months and low levels of these parameters during the summ ... | 1984 | 6149060 |
| case report. oxalate nephrosis in chinchilla (chinchilla laniger). | 1970 | 5533662 | |
| chinchilla laniger--discrepancy between concentrating ability and kidney structure. | 1970 | 5411553 | |
| coexisting intrauterine and abdominal (intraperitoneal) pregnancy with possible superfoetation (superfecundation) and with adhesion of placenta to foetus in a chinchilla (chinchilla laniger). | 1969 | 5407710 | |
| cellular blood constituents and serum protein fractions of the chinchilla (chinchilla lanigera). | 1971 | 5113541 | |
| steroid metabolic pathways in the ovary of the chinchilla (chinchilla laniger). | 1972 | 5061156 | |
| listeriosis in chinchillas (chinchilla laniger). | 1967 | 4962151 | |
| protein nutrition and lymphocyte responsiveness to phytomitogens in the chinchilla (chinchilla lanigera). | 1974 | 4817543 | |
| paracrystalline aggregates of microtubules in the anterior pituitary cells of the chinchilla (chinchilla laniger) (1). | 1974 | 4810013 | |
| varieties of habituation in the chinchilla (chinchilla lanigera). | 1974 | 4809967 | |
| the digestion of carbohydrates in the chinchilla (chinchilla lanigera). | 1974 | 4418900 | |
| water relations of the chinchilla chinchilla laniger. | 1972 | 4401725 | |
| the clinical effects of ci 744 in chinchillas, chinchilla villidera (laniger). | 1974 | 4370757 | |
| spontaneous herpes-like viral infection in a chinchilla (chinchilla laniger). | 1970 | 4316481 |