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1.
本试验探讨了噪声对AA鸡生长以及血液生理生化指标的影响。供试鸡为100只15日龄的AA鸡,把其按交叉分组法分为四组(1个对照组和3个试验组),对照组不给噪声,试验组(A、B、C)组分别给予70分贝、80分贝、90分贝的噪声,试验期为30天。结果表明,噪声能引起:增重显著减缓,90分贝组鸡增重与对照组差异显著;屠宰率、全净膛率显著降低,80分贝,90分贝组屠宰率与对照组差异显著,90分贝组全净膛率与对照组差异显著:甲状腺素浓度A、B、C组与对照组相比,依次降低,且试验组与对照组差异显著。  相似文献   

2.
飞机噪声对乳牛的影响   总被引:1,自引:0,他引:1  
为了进一步了解飞机噪声对乳牛的影响,本研究抽样调查了82头泌乳期黑白花母牛在飞机低空飞行时噪声影响前后的生理表现.飞机噪声使母牛出现明显的应激和狂暴,并干扰了母牛正常的泌乳反射.噪声使当日早晨个体平均挤乳量由正常的10.11±2.56kg降至9.14±2.83kg.噪声对乳牛的影响有延续性,在噪声发生后的第二个早晨,挤乳量继续降至9.22±2.70kg水平.因此,乳牛场的选址应避开空运航线.  相似文献   

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Dorsal displacement of the soft palate (DDSP) usually occurs in athletic adult horses. Congenital DDSP in foals secondary to the persistent frenulum of the epiglottis is rarely observed. The aim of this report was to describe a case of a seven-day-old female neonate Quarter Horse presenting dysphagia, milk reflux through the nostrils and mouth, and expiratory dyspnea since 4 days. Thoracic auscultation was indicative of aspiration pneumonia. Diagnosis of DDSP associated with local inflammation was made after endoscopic examination of upper respiratory tract. Radiographic examination was performed to rule out hypoplasia of the epiglottis. No clinical improvement was observed after anti-inflammatory treatment with flunixin meglumine. Oral endoscopy under general anesthesia revealed that the displacement of the soft palate was caused by a persistent frenulum of the epiglottis. Using a 30° rigid endoscope and a curved laparoscopic scissors, the frenulum was transected. After surgery, no dysphagia or dyspnea at rest was observed. However, discreet respiratory noise persisted during exercise for 5 days postoperatively. After discharge, the owner reported that the animal was completely normal during exercise. The animal is currently 3 years old and is developing a normal athletic performance. Persistent frenulum of the epiglottis should be considered while examining neonates with nasal milk reflux associated with expiratory dyspnea. This case report emphasizes the importance of the differential diagnosis for DDSP and for DDSP secondary to the persistent frenulum of the epiglottis in neonatal foals. It also underlines the importance of oral endoscopic examination for diagnosis.  相似文献   

6.
Pacemakers are commonly implanted by veterinary cardiologists in dogs with bradyarrhythmias. In the past, these pacemakers were placed with little attention to programming except for the basic heart rate. However, the availability of pacing programmers has permitted a better appreciation of the needs for proper and safe pacing in dogs. An awareness of the problems that can result from improper programming is imperative. We report the identification of noise reversion (inappropriate asynchronous pacing) in 42% of dogs consecutively paced (n = 19) at Cornell University during a 2 year period. Noise reversion is the operation that causes the pacemaker to switch to asynchronous pacing with repetitive refractory sensing. It was developed as a protective mechanism against noise being mistaken for cardiac events with the consequence of inhibition of pacing. However, in the dog, this operation can cause inappropriate, and potentially dangerous pacing. In the dog, this common complication is associated with the coexistence of a bradycardia and tachycardia. Proper programming of the refractory period (shortening) in conjunction with the sensitivity (decreasing the sensitivity) can eliminate noise reversion in dogs with both ventricular and atrial pacing.  相似文献   

7.
Shipping noise is a widespread and relatively loud sound source among human‐induced underwater sounds. The impacts of shipping noise are of special concern for Indo‐Pacific humpback dolphins (Sousa chinensis), as they inhabit shallow and nearshore habitats and are highly dependent on sound for survival. This study synthesizes our current understanding of the potential impacts of shipping noise on Indo‐Pacific humpback dolphins combined with knowledge on sound production and hearing of these animals and the impacts of noise on other whales and dolphins. For further protection and management of Indo‐Pacific humpback dolphins and their habitats, shipping noise should be regulated and mitigated to modify sound from ships, to reduce overall noise levels, and to set more marine protected areas (MPAs) covering most Indo‐Pacific humpback dolphin habitats with seasonal and geographical restrictions to avoid ensonification of shipping noise. The emphasis for future research should be on obtaining more baseline information about the population distribution, sound production, hearing capabilities at the population level, behavior, and stress hormones of the humpback dolphins under different noise conditions or under different noise‐producing activities, and/or in high‐noise areas compared with relatively quiet areas, and the noise characteristics of ships of different types, sizes and speeds.  相似文献   

8.
An enriched environment is widely used to improve domestic animals’ welfare and promote their natural behaviors. Music can reduce abnormal behavior in humans, nonhuman primates, and rodents. However, little is known about the effects of music on pigs. This study aims to explore the effects of repeated music stimulation on the behavior, physiology, and immunity of growing pigs. A total of 72 hybrid piglets (Large White × Duroc × Minpig) were randomly divided into three groups, including music (Mozart K.448, 60 to 70 dB), noise (recorded mechanical noise, 80 to 85 dB), and control (natural background sound, <40 dB), and 6 h sound stimulation was given per day (1000 to 1600 hours) from 40 to 100 d of age. The behavioral activities of the pigs were observed during the music stimulation, and their serum cortisol, salivary cortisol, and serum immune indices were also measured. Compared with the control group, the music group and noise group increased activity but decreased lying of pigs (P < 0.05). A significant increase in tail-wagging, playing, and exploring behaviors of pigs was found in the music group (P < 0.05), and the noise significantly increased the aggressive behavior of the pigs (P < 0.05). Tail-wagging, playing, exploring, manipulating, and aggressive behaviors decreased over time. Short-term (8 d) music stimulus had a lower cortisol level than that of the noise and control groups (P < 0.05), whereas long-term (60 d) music stimulus increased immunoglobulin G (IgG), interleukin-2 (IL-2), and interferon-gamma (IFN-γ) levels (P < 0.05) and decreased interleukin-4 (IL-4) level (P < 0.05). Long-term noise stimulus significantly reduced the level of IgG (P < 0.05) but did not affect the level of IL-2, IL-4, and IFN-γ levels (P > 0.05). In conclusion, short-term music stimulus (8 d) reduced the stress response, whereas long-term music stimulus (60 d) enhanced the immune responses. In addition, the noise increased the aggressive behavior, and long-term noise reduced the immunity of the growing pigs.  相似文献   

9.
An 18-month-old Welsh Cob was referred to a university teaching hospital for investigation of abnormal respiratory noise at rest. Video-endoscopy revealed persistent displacement of the soft palate with bilateral 2–3 cm diameter raised areas on either side of the midline. Neither trans-nasal nor oral approaches allowed sufficient visualisation of the caudal soft palate for diagnosis or treatment. Latero-lateral radiographs showed a blunted, thickened caudal edge of the soft palate consistent with a palatal cyst. Two palatal cysts were thermally ablated with a transendoscopic diode laser via temporary tracheotomy. The horse recovered uneventfully and resolution of the displacement was evident on follow-up endoscopy 11 months later. This report documents a novel surgical approach to the caudal aspect of the soft palate.  相似文献   

10.
This case report describes the endoscopic findings and outcome in 6 horses diagnosed with dynamic epiglottic retroversion (ER) during exercise. Horses included 2 showjumpers, one eventer, one pleasure riding horse and 2 Thoroughbred racehorses. All were adults (age range: 4–10 years). Dorsal angulation of the epiglottis was identified at rest in one horse. However, resting endoscopy was unremarkable in the remaining 5 horses. Exercising endoscopy was performed during high‐speed treadmill exercise in 3 horses and during ridden exercise in the other 3. Intermittent ER occurred during inspiration in all horses and the frequency increased with increasing speed. In 2 horses the epiglottis retroverted beyond the rima glottidis. All horses made an abnormal respiratory noise described as a ‘grunt’ when retroversion of the epiglottis occurred. Poll flexion was found to be an exacerbating factor in the nonracehorses. Two horses continued in work but abnormal inspiratory noise persisted. Surgical treatment, in the form of subepiglottic resection, was attempted in one horse. However, it never raced again after the procedure. Of the remaining horses, 2 were retired and the third was subjected to euthanasia.  相似文献   

11.
Reasons for performing study: Little is known about the efficacy of bilateral ventriculectomy (VE) or bilateral ventriculocordectomy (VCE) in draught horses. Objectives: To compare the effect of VE and VCE on upper airway noise in draught horses with recurrent laryngeal neuropathy (RLN) by use of quantitative sound analysis techniques. Hypothesis: In competitive draught horses with grade 4 RLN, VE and VCE reduce upper airway noise during exercise, but VCE is more effective. Methods: Thirty competitive hitch or pulling draught horses with grade 4 RLN were evaluated for upper airway sound during exercise. Respiratory rate (RR), inspiratory (Ti) and expiratory time (Te), the ratio between Ti and Te (Ti/Te), inspiratory (Sli) and expiratory sound levels (Sle), the ratio between Sli and Sle (Sli/Sle), and peak sound intensity of the second formant (F2) were calculated. Eleven horses were treated with VE and 19 with VCE. After 90 days of voice and physical rest and 30 days of work, the horses returned for post operative upper airway sound evaluation and resting videoendoscopy. Results: VE significantly reduced Ti/Te, Sli, Sli/Sle and the sound intensity of F2. Respiratory rate, Ti, Te and Sle were unaffected by VE. VCE significantly reduced Ti/Te, Ti, Te, Sli, Sli/Sle and the sound intensity of F2, while RR and Sle were unaffected. The reduction in sound intensity of F2 following VCE was significantly greater than following VE. After VE and VCE, 7/11 (64%) and 15/18 (83%) owners, respectively, concluded that the surgery improved upper airway sound in their horses sufficiently for successful competition. Conclusions: VE and VCE significantly reduce upper airway noise and indices of airway obstruction in draught horses with RLN, but VCE is more effective than VE. The procedures have few post operative complications. Potential relevance: VCE is recommended as the preferred treatment for RLN in draught horses. Further studies are required to evaluate the longevity of the procedure's results.  相似文献   

12.
Many studies based on acute short‐term noise exposure have demonstrated that animals can adjust their vocalizations in response to ambient noise. However, the effects of chronic noise over a relatively long time scale of multiple days remain largely unclear. Bats rely mainly on acoustic signals for perception of environmental and social communication. Nearly all previous studies on noise‐induced vocal adjustments have focused on echolocation pulse sounds. Relatively little is known regarding the effects of noise on social communication calls. Here, we examined the dynamic changes in the temporal parameters of echolocation and communication vocalizations of Vespertilio sinensis when exposed to traffic noise over multiple days. We found that the bats started to modify their echolocation vocalizations on the fourth day of noise exposure, with an increase of 42–91% in the total number of pulse sequences per day. Under noisy conditions, the number of pulses within a pulse sequence decreased by an average of 17.2%, resulting in a significantly slower number of pulses/sequence (P < 0.001). However, there was little change in the duration of a pulse sequence. These parameters were not significantly adjusted in most communication vocalizations under the noise condition (all P > 0.05), except that the duration decreased and the number of syllables/sequences increased in 1 type of communicative vocalization (P < 0.05). This study suggests that bats routinely adjust temporal parameters of echolocation but rarely of communication vocalizations in response to noise condition.  相似文献   

13.
Geographic variations in the dolphin whistles could be useful in assessing association and isolation among populations. Whistle of free-ranging Indo-Pacific humpback dolphins (Sousa chinensis) among the Pearl River Estuary (PRE), Leizhou Bei (LZB) and Sanniang Bay (SNB) populations were investigated. A total of 2850 whistles with legible fundamental contour were extracted and 15 acoustic parameters were measured. Contrary to SNB, PRE and LZB had the same relative proportion of tonal type compositions with flat and sine representing the most frequent types. The generalized linear model analysis showed significant acoustic difference among populations and tonal types. All frequency parameters in SNB were significantly higher than those in PRE and LZB, where no significant variation was observed in most of the parameters either at the population level or within each tonal type. Canonical discriminant functions analysis showed a smaller difference between PRE and LZB than between PRE and SNB and between LZB and SNB. Compared with previous recordings, recent recordings demonstrated a consistent pattern of becoming higher in whistle frequency parameters in both LZB and SNB populations, suggesting that noise pollution in LZB and SNB increasing with time according to the acoustic niche hypothesis. Dolphin whistle's geographic variations could be shaped by the combined function of the geographical barrier function of the Qiongzhou strait and local ambient noise. Considering the isolated condition and the relatively smaller population size of the humpback dolphin in the SNB, more effective and proactive conservation actions should be taken to prevent the extinction of small populations.  相似文献   

14.
OBJECTIVE: To evaluate the efficacy and tolerance of a treatment protocol for obsessive-compulsive disorder, separation anxiety and noise phobia in dogs. DESIGN: A study was undertaken to assess clinical responses in 24 dogs diagnosed with one or more of three behavioural disorders stated above to a treatment regimen that included clomipramine and behaviour modification. PROCEDURE: A detailed behavioural and clinical history was obtained for each dog. Obsessive-compulsive disorder was diagnosed in nine cases: primary presenting complaints were tail-chasing, shadow-chasing, circling and chewing; one case was diagnosed with concurrent separation anxiety. Separation anxiety was diagnosed in 14 cases: presenting complaints included destruction, vocalisation and escaping in the absence of the owner; four cases also exhibited noise phobia. The study also included one dog diagnosed with noise phobia only and another with inappropriate fear responses. Clomipramine was administered orally twice daily. The starting dose was 1 to 2 mg/kg bodyweight. The dose was increased incrementally to a maximum of 4 mg/kg if needed. A behaviour modification program was designed and the owner instructed on its implementation. Dogs continued medication for at least 1 month after clinical signs disappeared or were acceptably reduced, then withdrawal of medication was attempted by decreasing drug dosage at weekly intervals while behaviour modification continued. RESULTS: The presenting clinical sign was largely improved or disappeared in 16 dogs, 5 demonstrated slight to moderate improvement and the behaviour was unchanged in 3. Clomipramine withdrawal was attempted in nine cases: this was successful in five. CONCLUSION: Clomipramine was effective and well-tolerated in controlling signs of obsessive-compulsive disorder and/or separation anxiety and/or noise phobia in 16 of 24 assessable cases, when used in combination with behaviour modification, and improvement in clinical signs was noted in 5 others.  相似文献   

15.
研究光照和噪声对小鼠血液指标及肝肾功能的影响。将昆明(KM)小鼠分别放在不同光照和噪声条件下,探讨光照、噪声对KM小鼠血液常规和血清生化指标的影响。结果显示,不利的光照和噪声条件造成血常规中红细胞、血红蛋白数改变,平均红细胞血红蛋白含量、平均红细胞血红蛋白浓度发生变化;血清中ALT和AST浓度升高;ALB升高;CREA、UREA和UA降低;TG、GLU降低。可见不适宜的光照(小于150lx或大于300lx)和噪声(大于60dB)环境对实验动物的肝肾功能有一定的损害,导致实验动物消化不良,出现营养不良、贫血、脱水等症状,因此实验动物环境因素与动物福利有着密切的关系。  相似文献   

16.
The associations between feeding activities and environmental variables inform animal feeding tactics that maximize energetic gains by minimizing energy costs while maximizing feeding success. Relevant studies in aquatic animals, particularly marine mammals, are scarce due to difficulties in the observation of feeding behaviors in aquatic environments. This data scarcity concurrently hinders ecosystem-based fishery management in the context of small toothed-cetacean conservation. In the present study, a passive acoustic monitoring station was deployed in an East Asian finless porpoise habitat in Laizhou Bay to investigate potential relationships between East Asian finless porpoises and their prey. The data revealed that porpoises were acoustically present nearly every day during the survey period. Porpoise detection rates differed between spring and autumn in concert with activities of fish choruses. During spring, fish choruses were present throughout the afternoon, and this was the time when porpoise vocalizations were the most frequently detected. During autumn, when fish choruses were absent, porpoise detection rates decreased, and diurnal patterns were not detected. The close association between fish choruses and finless porpoise activities implies an “eavesdropping” feeding strategy to maximize energetic gains, similar to other toothed cetaceans that are known to engage similar feeding strategies. Underwater noise pollution, particularly those masking fish choruses, could interrupt finless porpoises’ feeding success. Fisheries competing soniferous fishes with finless porpoise could impact finless porpoise viability through ecosystem disruption, in addition to fishing gear entanglement.  相似文献   

17.
The underwater soundscape is an important ecological element affecting numerous aquatic animals, in particular dolphins, which must identify salient cues from ambient ocean noise. In this study, temporal variations in the soundscape of Jiaotou Bay were monitored from February 2016 to January 2017, where a population of Indo-Pacific humpback dolphins (Sousa chinensis) has recently been a regular sighting. An autonomous acoustic recorder was deployed in shallow waters, and 1/3-octave band sound pressure levels (SPLs) were calculated with central frequencies ranging from 25 Hz to 40 kHz, then were grouped into 3 subdivided bands via cluster analysis. SPLs at each major band showed significant differences on a diel, fishing-related period, seasonal, and tidal phase scale. Anthropogenic noise generated by passing ships and underwater explosions were recorded in the study area. The fish and dolphin acoustic activities both exhibited diel and seasonal variations, but no tidal cycle patterns. A negative significant relationship between anthropogenic sound detection rates and dolphin detection rates were observed, and fish detection rates showed no effect on dolphin detection rates, indicating anthropogenic activity avoidance and no forced foraging in dolphins in the study area. The results provide fundamental insight into the acoustic dynamics of an important Indo-Pacific humpback dolphin habitat within a coastal area affected by a rapid increase in human activity, and demonstrate the need to protect animal habitat from anthropogenic noises.  相似文献   

18.
北京鸿华高尔夫球场生态环境效益评价研究   总被引:1,自引:0,他引:1  
通过对北京鸿华高尔夫球场内外的PM 2.5、PM 10、空气负离子、温湿度及噪音等生态效益因子连续14 d的实地监测,分析其日变化规律、不同立地条件下的差异及各因子间的相关性,结果表明:球场内各生态效益因子的含量均优于球场外,并且乔灌草复合绿地对各因子的净化效率均高于乔草型和草坪型绿地。温湿度日变化曲线分别呈现单峰和单谷状,日平均气温降低2.1℃,增加相对湿度9.2%。PM 2.5与PM 10的日变化规律呈现出双峰趋势,早晚较高,午后较低,球场对两者的日均净化率分别为25.9% 和26.6%,并且两者间具有极显著的正相关性,其含量与温湿度分别呈极显著的正相关性和负相关性。球场内空气负离子早晚较高,午后较低,其含量是球场外的4.95倍,与温湿度分别呈现出极显著的负相关性和正相关性。球场内的噪声显著低于球场外,平均降噪率为11.8%,其日变化规律呈现出先上升,然后基本保持微小波动的趋势。  相似文献   

19.
OBJECTIVE: To report the effect of unilateral laser vocal cordectomy on respiratory noise and airway function in horses with experimentally induced laryngeal hemiplegia (LH). STUDY DESIGN: Experimental study. ANIMALS: Six Standardbred horses without upper airway abnormalities at rest or during high-speed treadmill exercise. METHODS: Respiratory sounds and inspiratory trans-upper airway pressure (P(Ui)) were measured before (baseline) and 14 days after induction of LH by left recurrent laryngeal neurectomy, and again 30, 60, 90, and 120 days after endoscopically assisted laser cordectomy of the left vocal cord. Data were collected with the horses exercising on a treadmill at a speed producing maximum heart rate (HR(max)). RESULTS: In horses exercising at HR(max), induction of LH caused a significant increase in P(Ui), sound level (SL), and the sound intensity of formant 2 (F(2)) and 3 (F(3)). The sound intensity of formant 1 (F(1)) was unaffected by induction of LH. Laser vocal cordectomy had no effect on SL, or on the sound intensity of F(1) and F(3). At 30, 60, 90, and 120 days after surgery, P(Ui) and the sound intensity of F(2) were significantly reduced, but these variables remained significantly different from baseline values. CONCLUSIONS: Unilateral laser vocal cordectomy did not effectively improve upper airway noise in horses with LH. The procedure decreased upper airway obstruction to the same degree as bilateral ventriculocordectomy. CLINICAL RELEVANCE: Currently, laser vocal cordectomy cannot be recommended for the treatment of upper airway noise in horses with LH.  相似文献   

20.
It is important to optimize digital radiographic technique settings for small animal imaging in order to maximize image quality while minimizing radiation exposure to personnel. The purpose of this study was to evaluate two objective methods for determining optimal kVp values for an indirect flat panel digital detector. One method considered both image quality and personnel exposure as endpoints and one considered only image quality. Phantoms simulated veterinary patients of varying thicknesses with lesions of varying sizes. Phantoms were exposed to a range of kVp values (60, 81, 100, and 121), using different mAs settings for each phantom. Additionally, all phantoms were exposed to a standard test exposure of 100 kVp/2.5 mAs. Scattered radiation was recorded and used as a measure of personnel exposure. When personnel exposure was considered, a figure of merit was calculated as an endpoint of optimization. The optimal kVp value for each phantom was determined based on the highest signal difference‐to‐noise ratio with or without inclusion of the figure of merit. When personnel exposure was not considered, increasing kVp resulted in higher signal difference‐to‐noise ratios and personnel exposure increased when both patient thickness and kVp increased. Findings indicated that a single standard technique of 100 kVp/2.5 mAs was only optimal for most medium‐sized patients. Images of thinner patients should be made with a lower kVp. Very large patients require a higher kVp than 100 regardless of the optimization method used. Personnel exposure from optimized techniques was low and not expected to exceed annual occupational dose limits.  相似文献   

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