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1.
A co–axial non–rebreathing circuit for use in small animal anaesthesia is described. The advantages and disadvantages of this type of circuit are discussed in relation to other circuits in current use.  相似文献   

2.
Sixty-four anaesthetic machines and 89 breathing circuits were surveyed in New Zealand veterinary practices. Each machine and circuit was tested for correct function. Sixty-six percent of machines checked were 10 years or older and vaporiser out-of-circuit machines totalled 72% of machines surveyed. Twenty-five percent of the temperature compensated vaporisers had been serviced within the previous 1 year, 33% serviced between 1 and 10 years ago, while the remaining 42% had no service record or had not been serviced for over 10 years. Sixty-six percent of machines had some type of scavenging device. Nineteen percent of machines had a leak in the high pressure system. Thirty percent of the anaesthetic machine low pressure systems leaked and 76% of the patient breathing circuits leaked. Overall, 91% of all anaesthetic machines and breathing circuits showed malfunctions which could increase practice operating costs, increase the exposure of practice personnel to anaesthetic agents, and increase patient morbidity.  相似文献   

3.
Animal scientists have an extraordinary burden to promote the health and well-being of all animals in their care. Promoting species- or breed-appropriate behaviors through proper training and enrichment, regardless of animal housing, should be a paramount concern for all animal scientists working with exotic animals, laboratory animals, shelter animals, or privately owned pet animals. Developing ideal training and enrichment programs for any species begins with understanding basic behavior patterns and emotional systems of animals. The basic emotional systems in mammals have been extensively mapped; however, most of these studies are in the neuroscience literature and seldom read by animal science professionals. The emotional circuits for fear have been well documented through studies demonstrating that lesions to the amygdala will block both conditioned and unconditioned fear behaviors. Additionally, other core emotional systems including seeking (i.e., approaching a novel stimulus), rage, panic (e.g., separation stress), play, lust (i.e., sex drive), and care (e.g., mother-young nurturing behavior) have been identified. More recent neuroscience research has discovered the subcortical brain regions that drive different types of seeking behaviors. Research to increase the understanding of the emotional systems that drive both abnormal and normal animal behaviors could greatly improve animal welfare by making it possible to provide more effective environmental enrichment programs. Enrichment devices and methods could be specifically designed to enable the expression of highly motivated behaviors that are driven by emotional circuits in the brain. The objective of this paper is to increase awareness of animal scientists to the field of neuroscience studying animal emotions and the application of that science to improve the welfare of captive exotic animals, laboratory animals, and pets with environmental enrichment.  相似文献   

4.
The copulatory behavior and the parvocellular vasotocin (VT) system of the nucleus of the stria terminalis (BST) are sexually dimorphic in the Japanese quail. Embryonic administration of estradiol benzoate (EB) induces an organizational effect determining the disappearance of such a dimorphism (male shows behavior and cerebral phenotype of the female). The VT parvocellular system can therefore be considered an accurate marker of the sexual differentiation of brain circuits and a very sensitive indicator of the activity of estrogen-like substances on neural circuits. To test this hypothesis we administered diethylstilbestrol (DES), a powerful synthetic xenoestrogen, genistein (GEN), a phytoestrogen produced by soy, and bisphenol A (BPA). After 3 days of incubation, quail eggs were injected with vehicle, EB, DES, GEN or BPA. Administration of BPA caused an early blockage of development and no further analyses were done on the BPA groups. At puberty, the copulatory behavior of EB- or DES-treated male quail was totally abolished, whereas only the highest doses of GEN determined a significant decrease of the behavior. After the tests, the animals were sacrificed and perfused. The fractional area (FA) covered by VT immunoreactivity was analyzed in BST, medial preoptic nucleus, and lateral septum by computerized image analysis. The FA was significantly reduced after treatment with EB, DES and GEN at high doses. These results confirm that the sexually dimorphic VT system of the Japanese quail is a sensible indicator of the effects of xenoestrogens at the level of the central nervous system.  相似文献   

5.
Minireview     
Received July, 1998; accepted for publication July, 1998
The olfactory epithelium is unique in the mammalian nervous system as it is a site of continual neurogenesis. Constant turnover of primary sensory neurons in the periphery results in continuous remodeling of neuronal circuits and synapses in the olfactory bulb throughout life. Most of the specific mechanisms and factors that control and modulate this process are not known. Recent studies suggest that growth factors, and their receptors, may play a crucial role in the development and continuous regeneration of olfactory neurons, i.e. particularly in neuronal proliferation, neurite outgrowth, fasciculation and synapse formation of the olfactory system. The potential role of the following factors and their receptors in different species are reviewed: Nerve growth factor (NGF); insulin-like growth factors (IGFs); fibroblast growth factors (FGFs); epidermal growth factor (EGF); transforming growth factor α (TGF α); amphiregulin (AR) and transforming growth factors β (TGFs β).  相似文献   

6.
The olfactory epithelium is unique in the mammalian nervous system as it is a site of continual neurogenesis. Constant turnover of primary sensory neurons in the periphery results in continuous remodeling of neuronal circuits and synapses in the olfactory bulb throughout life. Most of the specific mechanisms and factors that control and modulate this process are not known. Recent studies suggest that growth factors, and their receptors, may play a crucial role in the development and continuous regeneration of olfactory neurons, i.e. particularly in neuronal proliferation, neurite outgrowth, fasciculation and synapse formation of the olfactory system. The potential role of the following factors and their receptors in different species are reviewed: Nerve growth factor (NGF); insulin-like growth factors (IGFs); fibroblast growth factors (FGFs); epidermal growth factor (EGF); transforming growth factor alpha (TGF alpha); amphiregulin (AR) and transforming growth factors beta (TGFs beta).  相似文献   

7.
Actually, some 67% of therapeutical used antibiotics in livestock in the European Union are tetracyclines. Their use can result in unwanted residues in food of animal origin. Apart the risk of the possible development of resistances in enterobacteriaceae we have to keep in mind secondary circuits. This paper focuses on tetracycline residues in bones. Bones have been widely used as raw material for meat and bone meal and gelatine, and are also a frequent contamination of mechanical recovered meat. Bones contain tetracycline residues in concentrations up to 50 mg/kg. These bound tetracycline residues have ever been thought to be of no significance to health. Nevertheless, recent studies have shown that these tetracyclines could be released in vivo and re-obtain their bioavailability. Further, several toxic degradation products of tetracyclines could be formed during heating. Additionally, in acid solutions from the production of gelatine high tetracycline concentrations have been found. These solutions are processed to dicalciumphosphate, which is used as a feed supplement in animal husbandry and as fertilizer in agriculture.  相似文献   

8.
Four cell types including the bipolar, amacrine, horizontal and Muller cells were investigated quantitatively in the inner nuclear layer of the retina in the horse. Cells were identified on the basis of the morphology and distribution of processes leaving from their somata, cytological features and positional features. The average percentages of the above 4 cell types were 44%, 24%, 1% and 29%, respectively. The average total cell densities in the inner nuclear layer in the visual streak, the nasal and temporal regions, the dorsal and ventral regions of the retina were also estimated. It is expected that the results of this study will supply the basic data for further study of the neural circuits in the horse retina.  相似文献   

9.
Chronic exposure to trace levels of waste anesthetic gases has been linked to higher incidences of neurologic and reproductive dysfunction, hepatic and renal toxicity, and neoplasia in health care professionals. We have shown that low levels of isoflurane emissions are likely in conventional laboratory animal treatment rooms during the use of standard anesthesia delivery systems equipped with activated charcoal canisters for passive gas scavenging. In the present study, we surveyed the effectiveness of canisters (attached to well‐maintained precision isoflurane vaporizers) in current use throughout our AAALAC‐accredited laboratory animal facility. Canisters (Omnicon f/air) had been weighed prior to use and then attached to dual‐loop systems (face mask and induction box circuits) from 1 week to 6 months of service. Isoflurane emissions were measured using a pre‐calibrated, portable infrared spectrophotometer by attaching each canister to the face‐mask circuit, occluding the face mask and closing the stopcock to the induction circuit, and running the system at uniform isoflurane concentration (2%) and oxygen flow rate (1 L minute?1). Samples were taken in animal procedure rooms (size range, 45–80 m3) in which the air turnover rate ranged between 20 and 30 nonrecirculating changes per hour. Nine of the 60 canisters (15%) in current use were found to have exceeded the manufacturer's recommended use‐life (defined as a weight increase of 50 g). Of these nine, seven canisters did not scavenge isoflurane at all (indicated by emissions greatly exceeding 100 ppm). Isoflurane was not detected in the operator's breathing zone under normal use conditions (i.e. gas directed to both circuits at once). Of the 51 canisters that had not exceeded their rated use‐life, 12 (23.5%) exhausted isoflurane at >2 ppm. Our data show that (i) the potential for exposure to waste isoflurane emissions will depend on the configuration of the delivery system and that (ii) enhanced attention to canister surveillance may be warranted even in well‐run facilities.  相似文献   

10.
Pseudorabies virus (PRV), an alpha-herpesvirus, is capable of spreading between synaptically connected neurons in diverse hosts. In this report, two lines of experimentation are summarized that provide insight into the mechanism of virus spread in neurons. First, techniques were developed to measure the transport dynamics of capsids in infected neurons. Individual viral capsids labeled with green fluorescent protein (GFP) were visualized and tracked as they moved in axons away from infected neuronal cell bodies in culture during egress. Second, the effects of three viral membrane proteins (gE, gI and Us9) on the localization of envelope, tegument, and capsid proteins in infected, cultured sympathetic neurons were determined. These three proteins are necessary for spread of infection from pre-synaptic neurons to post-synaptic neurons in vivo (anterograde spread). Us9 mutants apparently are defective in anterograde spread in neural circuits because essential viral membrane proteins such as gB are not transported to axon terminals to facilitate spread to the connected neuron. By contrast, gE and gI mutants manifest their phenotype because these proteins most likely function at the axon terminal of the infected neuron to promote spread. These two sets of experiments are consistent with a model for herpesvirus spread in neurons first suggested by Cunningham and colleagues where capsids and envelope proteins, but not whole virions, are transported separately into the axon.  相似文献   

11.
The effect of low-level direct-current stimulation on skin wound healing in the horse was assessed. Self-sustaining electrical circuits with electrodes were implanted subcutaneously in or near the wound. Stimulation by direct current (10 or 20 microA) was used to determine the effect on equine skin healing. The efficacy of electrotherapy was evaluated by sequentially comparing the clinical appearance of the wound and measuring the size of the granulating wound bed. The histologic appearance of the healing stimulated wounds was compared with that in nonstimulated control wounds created on 9 horses. Seemingly, electrical stimulation had no discernible effect on experimentally created skin wounds. Clinical observation and histologic examination of the wounds indicated that severe tissue reaction from the implanted electrodes and concurrent local infection produced local detrimental effects to wound healing.  相似文献   

12.
The neurons associated with the left first sacral sympathetic trunk ganglion (STG S1), an autonomic ganglion particularly concerned in the innervation of the smooth and striated musculature associated with pelvic organs, were identified in the pig, using the non-trans-synaptic fluorescent retrograde neuronal tracer Fast Blue. The labelled neurons were located mostly ipsilaterally, in the intermediolateral nucleus of the spinal cord segments T10-L5, in the sympathetic trunk ganglia L3-Co1, in the caudal mesenteric ganglia, in the pelvic ganglia, and in the spinal ganglia T13-S4. Our results could indicate the existence of visceral neuronal circuits concerning the ganglia of the sympathetic trunk and the caudal mesenteric, pelvic and spinal ganglia with or without the intervention of the central nervous system, whose identification and preservation during surgical treatments could be helpful in reducing the risk of subsequent urinary and sexual disfunctions.  相似文献   

13.
The performance of the Lack co-axial breathing circuit was evaluated in 25 anaesthetized dogs breathing spontaneously. Fresh gas flows were adjusted until rebreathing started to occur as judged by capnography. Thus a critical fresh gas flow rate was determined for small (10–15 kg) and larger (15 + kg) dogs. These were 130.5 ± 31.2 and 95.9 ± 13-1 ml/kg/min respectively. In a further twenty dogs weighing over 15 kg a fresh gas flow rate of 120 ml/kg/min was used and was found to be sufficient to prevent rebreathing in all cases. In 11 dogs a direct comparison was made between the Lack and the Magill circuits with fresh gas flows of 120 ml/kg/min and it was found by capnography that while there was minimal or no rebreathing with the Lack system there was substantial rebreathing with the Magill.  相似文献   

14.
At present, Foot-and-Mouth Disease (FMD) has been successfully controlled in most territories of South America, where only Ecuador and Venezuela remain as endemic countries. In this context, the precise characterization of circulating viruses is of utmost importance. This work describes the first molecular epidemiology study performed with the complete VP(1)-coding region of 114 field isolates of FMD virus (FMDV) type O, collected in the Andean countries mainly during 2002-2008. Sequences were aligned and compared to isolates responsible for emergencies in the Southern Cone of the continent between the years 2000 and 2006, and to other representative type O viruses worldwide. The results showed that FMD type O viruses isolated in South America and analyzed up to date are placed in 11 different lineages within the Euro SA topotype. Five of these lineages included viruses circulating in Ecuador and Venezuela during 2002-2008. The last emergencies reported in already-free areas in the Andean region, showed close relationships with viruses circulating in these endemic countries. Andean lineages showed a clear separation from the unique lineage containing viruses responsible for the emergencies in the Southern Cone, reflecting the different livestock circuits and providing evidence that support the ecosystem dynamics in the region. A wide geographical dissemination of the same strain in short time intervals has been observed, pointing to animal movements as the most significant risk parameter. This fact, together with an important generation of viral variants in areas under weak control strategies, reinforce the need of stronger official controls, as well as for establishing multinational cooperative measures in the border areas.  相似文献   

15.
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16.
Feline immunodeficiency virus sustains an AIDS-like syndrome in cats, which is considered a relevant model for human AIDS. Under precise enrolment requirements, 30 naturally infected cats showing overt disease were included in a trial of low-dose, oral human interferon-alpha treatment. Twenty-four of them received 10 IU/Kg of human interferon-alpha and 6 placebo only on a daily basis under veterinary supervision. The low-dose human interferon-alpha treatment significantly prolonged the survival of virus-infected cats (p<0.01) and brought to a rapid improvement of disease conditions in the infected hosts. Amelioration of clinical conditions was neither correlated with plasma viremia, nor with proviral load in leukocytes. A good survival of CD4+ T cells and a slow increase of CD8+ T cells were also observed in human interferon-alpha-treated cats. Interestingly, the improvement of the total leukocyte counts showed a much stronger correlation with the recovery from serious opportunistic infections. As shown in other models of low-dose interferon-alpha treatment, there was a rapid regression of overt immunopathological conditions in virus-infected cats. This hints at a major role of interferon-alpha in the control circuits of inflammatory cytokines, which was probably the very foundation of the improved clinical score and survival despite the unabated persistence of virus and virus-infected cells.  相似文献   

17.
Fine tuning of the nervous system in response to intrinsic and extrinsic cues is necessary for successful reproductive behavior. Gonadotropin releasing hormone (GnRH) was originally identified as a hypophysiotropic hormone that facilitates the release of gonadotropins from the pituitary. Although later studies reported their presence, the nonhypophysiotropic GnRH systems, which consist of two groups located in the terminal nerve (TN) and the midbrain tegmentum, respectively, has long been overshadowed by the hypophysiotropic GnRH system. By taking advantage of the teleost brains in which all three GnRH systems are well developed, the anatomical and electrophysiological properties of all three groups of GnRH neurons have been studied. However, despite our increasing endocrinological knowledge, we know very little about the manner of information flow by nonhypophysiotropic neuromodulatory GnRH neurons in the brain. In this article, we will review recent advances in the studies of nonhypophysiotropic GnRH neurons from cellular to behavioral levels. We will first discuss general features of the information processing by peptides and then introduce our recent approaches toward the understanding of the excitation-secretion coupling mechanism of single GnRH neuron using our newly developed primary culture system of isolated TN-GnRH3 neurons. We also introduce autocrine/paracrine regulation of TN-GnRH3 neurons by NPFF peptides for synchronization among them. In addition, we highlight recent advances in the neuromodulatory action of GnRH peptide on the information processing of sensory neuronal circuits and reproductive behavior. These multidisciplinary approaches will greatly advance our understanding of the complex action of GnRH peptides in relation to the brain control of reproduction.  相似文献   

18.
Electrocution techniques were used to determine if treated targets similar to those used for tsetse control could be developed for stable fly control. In a series of two experiments, a half blue and half black (UK) 1 m2 target constructed of trigger cotton poplin was determined to be acceptable for development studies. In the first experiment, an average of 350 stable flies per hour (maximum 794 flies in 1 h) was collected using the UK target. A time-delayed circuit trial using untreated UK targets demonstrated that stable flies remained on or around the targets for at least 30 s. Two experiments were conducted with time-delayed circuits and UK targets treated with 0.1% lambda-cyhalothrin. In the first experiment, the number of flies collected using the 30 s on/off treated target treatment was not different from the number of flies collected using the other treatments. In the second experiment, the number of flies collected using the 30 s on/off treated target treatment was not different than the untreated target continuous or 30 s on/off treatments, but was significantly lower than the treated target continuous treatment. The number of flies collected with UK trigger targets was significantly higher than that for alsynite cylinder traps in two experiments. The mean number of flies collected during 22 1h assays using targets was 6.1-fold higher than that for alsynite traps, and the mean number of flies collected during 40 3 h using the targets also was 6.1-fold higher than that for alsynite traps. The results of this study indicate that treated cloth targets may be a viable addition for stable fly control programs.  相似文献   

19.
The response to acute cold (-5 degrees C) of swine kept single was found to differ from that of animals kept in groups. Such difference in reaction was reflected in significant variation of plasma concentration curves in catechol amines and 11-OHKS during and after acute exposure to cold. The response to cold stimulation of animals kept single was primarily and pronouncedly via the sympathicoadrenal system, whereas animals kept in groups responded to acute cold exposure, with the hypothalamic-adrenocortico-pituitary system playing the major role. Significant rise in PBJ in response to 30 and 90 minutes of exposure to cold was recorded only from animals kept single and interpreted as an expression of strong adrenergic reaction of such probands. Such difference in response to one and the same acute stimulus supported the conclusion that there was a difference in adaptation capacity between animals in those two keeping conditions. The results also suggested that type and degree of organic response to a specific stimulus were likely to depend not only on the intensity of the given stimulus, but also on the control potential produced by all closely interconnected control circuits at the time of stimulation.  相似文献   

20.
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