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151.
152.
Injury to the gracilis muscle can cause acute, severe lameness in horses. Two female Quarter Horses that were used for barrel racing sustained gracilis muscle tear injuries. The site of injury was localized by direct infiltration of the area with mepivacaine. The extent of muscle tearing and seroma formation was determined via ultrasonographic evaluation. One horse developed fibrotic myopathy approximately 3 months after the original injury and underwent surgery to transect a palpable fibrous band at the previous injury site. Both horses returned to barrel racing 5 to 6 months after the injury These results suggest that horses sustaining a gracilis muscle injury have a good prognosis for returning to athletic use after an adequate period of muscle healing; however, fibrotic myopathy or muscle atrophy could be a complication of the injury resulting in persistent gait deficits.  相似文献   
153.

Objective

To characterise the minimum dose of intramuscular alfaxalone required to facilitate intubation for mechanical ventilation, and to investigate the impact of cranial versus caudal injection on anaesthetic depth.

Study design

Randomised crossover study.

Animals

Six healthy juvenile ball pythons (Python regius).

Methods

Three dosages (10, 20 and 30 mg kg–1) of alfaxalone were administered to each python in a caudal location with a minimum 2 weeks washout. Induction and recovery were monitored by assessing muscle tone, righting reflex, response to a noxious stimulus and the ability to intubate. A subsequent experiment assessed the influence of injection site by comparing administration of 20 mg kg–1 alfaxalone in a cranial location (1 cm cranial to the heart) with the caudal site. Respiration rate was monitored throughout, and when intubation was possible, snakes were mechanically ventilated.

Results

Regardless of dose and injection site, maximum effect was reached within 10.0 ± 2.7 minutes. When administered at the caudal injection site, intubation was only successful after a dosage of 30 mg kg-1, which is higher than in previous reports for other reptiles. However, intubation was possible in all cases after 7.2 ± 1.6 minutes upon cranial administration of 20 mg kg–1, and anaesthetic duration was significantly lengthened (p < 0.001). Both 30 mg kg–1 at the caudal site and 20 mg kg–1 at the cranial site led to apnoea approximately 10 minutes post-injection, at which time the snakes were intubated and mechanically ventilated.

Conclusions and clinical relevance

Alfaxalone provided rapid, smooth induction when administered intramuscularly to pythons, and may serve as a useful induction agent prior to provision of volatile anaesthetics. The same dosage injected in the cranial site led to deeper anaesthesia than when injected caudally, suggesting that shunting to the liver and first-pass metabolism of alfaxalone occur when injected caudally, via the renal portal system.  相似文献   
154.
155.
The objectives of this study were to determine (i) if in subtropical goats that gave birth during mid‐December, the exposition to an artificial long‐day photoperiod consisting in only 14 hr of light per day can increase the milk yield and (ii) to test whether these females can respond to the male effect at the end of the prolonged photoperiodic treatment. In experiment 1, 17 lactating goats were maintained under natural short days (control group), while another 22 goats were maintained under artificial long days (treated group) consisting in 14 hr light and 10 hr darkness starting at day 10 of lactation. The continuous exposition to an artificial long‐day photoperiod produced an increase in the milk yield level during the first 110 days of lactation (time × treatment interaction; = .01), while none of the milk components were modified due to the photoperiodic treatment (> .05). In experiment 2, all control and treated anovulatory goats were submitted to the male effect using photostimulated males. All females showed oestrous behaviour within the first 10 days that were in contact with males (100% in both groups; > .05). Thus, the latency to onset of oestrus did not differ between females from control (58.2 ± 3.0 hr) and treated (62 ± 4.6 hr) groups. Male exposition provoked ovulation independently if females were previously under long days or natural photoperiod (96 vs 100%, respectively; = .79). It was concluded that exposure to 14 hr of light per day in subtropical goats that gave birth in late autumn stimulates milk yield without preventing the ovulation in response to the male effect at the end of the prolonged photoperiodic treatment.  相似文献   
156.
CASE HISTORY AND CLINICAL FINDINGS: During April and May 2014 four horses aged between 5 months and 9 years, located in the Canterbury, Marlborough and Southland regions, presented with a variety of clinical signs including recumbency, stiffness, lethargy, dehydration, depression, and myoglobinuria suggestive of acute muscle damage. Two horses were subjected to euthanasia and two recovered. In all cases seeds of sycamore maple (Acer pseudoplatanus) or box elder (A. negundo) were present in the area where the horse had been grazing.

LABORATORY INVESTIGATION: The samaras (seeds) of some Acer spp. may contain hypoglycin A, that has been associated with cases of atypical myopathy in Europe and North America. To determine if hypoglycin A is present in the samaras of Acer spp. in New Zealand, samples were collected from trees throughout the country that were associated with historical and/or current cases of atypical myopathy, and analysed for hypoglycin A. Serum samples from the four cases and four unaffected horses were analysed for the presence of hypoglycin A, profiles of acylcarnitines (the definitive diagnosis for atypical myopathy) and activities of creatine kinase and aspartate aminotransferase.Markedly elevated serum activities of creatine kinase and aspartate aminotransferase, and increased concentrations of selected acylcarnitines were found in the case horses. Hypoglycin A was detected in the serum of those horses but not in the healthy controls. Hypoglycin A was detected in 10/15 samples of samaras from sycamore maple and box elder from throughout New Zealand.

DIAGNOSIS: Cases of atypical myopathy were diagnosed on properties where samaras containing hypoglycin A were also found.

CLINICAL RELEVANCE: Sycamore and box elder trees in New Zealand are a source of hypoglycin A associated with the development of atypical myopathy. If pastured horses present with clinical and biochemical signs of severe muscle damage then the environment should be checked for the presence of these trees. Horses should be prevented from grazing samaras from Acer spp. in the autumn.  相似文献   

157.
AIM: To determine the period prevalence of needlestick injury (NSI) at the Massey University Veterinary Teaching Hospital (VTH) and to identify handling and disposal practices that may contribute to the risk of NSI.

METHODS: Observations of personnel were conducted in the equine (EVH) and companion animal (CAH) clinics of the VTH during scheduled clinical activities over 9- and 10-day periods, respectively. The number and type of NSI incidents, needle uncapping, capping and disposal events were recorded for veterinarians, nurses and other personnel (visitors and students). The number of needle-related practices, as a proportion of observations, were compared between CAH and EVH, and veterinarians, nurses and others using χ2 tests.

RESULTS: Needlestick injury was not observed during 190 and 163 needle handling and disposal observations in the CAH and EVH, respectively. Uncapping of needles by mouth was observed and was practised more by veterinarians (15/119; 13%) than nurses (2/42; 5%) and others (6/193; 3%) (p=0.001). Two-handed needle recapping after use was observed 265/354 times, and the one handed scooping technique was rarely observed (8/352). In the case of needle disposal, EVH workers used a container that was not purpose built for disposal more than CAH staff (p=0.02), or placed them in a pocket more frequently (p=0.003). Needle disposal containers were available on adjacent bench tops for 65/190 (34%) CAH observations, but no EVH observations. For 51/163 (31%) EVH observations the needle disposal containers were located on the ground, whereas none were observed there in the CAH. No approved sharps containers were observed in the immediate EVH and CAH work areas for 47/163 (28.8%) and 1/191 (0.5%) needle-handling activities, respectively.

CONCLUSIONS: Unsafe needle-handling practices must be reduced by policies and training programmes to encourage safe needle-related practices, and ensuring that approved sharps containers are available in close proximity to where needles are used.  相似文献   

158.
A century ago the remains of a dog skeleton were found in an archaeological double human burial, near Bonn‐Oberkassel (Germany). Recent re‐examination of the dog remains revealed that they were about 14,500 years old. Based on the growth plates, the animal was considered to be approximately 7·5 months old at the time of death. Based on the minimal humeral diameter, it was calculated that it was approximately 0·47 m tall at the shoulder and weighed approximately 15·7 kg. The right proximal ulna of this skeleton showed osteoarthritis, manifested by an osteophyte of 5×3×1·5 mm3 at its cranial edge, with no identified primary developmental causes for osteoarthritis. Osteochondritis dissecans, joint incongruity and trauma are possible aetiologies. The left ulna did not reveal any abnormalities.  相似文献   
159.
This study was undertaken to describe and quantify the measurement uncertainty of commercially available soil moisture sensors in the field. Three different commercial types of soil moisture sensors (TDR, EC and GMS sensors) were placed in groups of 25 sensors each under turf on a 3 × 3 m plot. Readings were taken daily over a period of 10 weeks in order to estimate the extent of measurement scattering and to estimate the change of scattering with time. It was found that, on average, scattering changes significantly with time and changing moisture content, and is generally very high (mean absolute deviation up to 16% available field capacity) for the purpose of irrigation scheduling. The difference in scattering between the three methods was significant, so it would be fruitful to seek methods with lower scattering. The assumption that scattering of measurements relative to a starting point in lower than absolute values could not be confirmed. Received: 23 June 1999  相似文献   
160.
Specific land uses, many of them considered as traditional practices, have contributed to nature conservation in that they have given rise to a valued landscape and a high degree of biological and cultural diversity. The result is the rural cultural landscape, also characterised by its multi-functionality, stability and adaptation to local conditions. Nonetheless, the abandonment of rural cultural landscapes constitutes the current trend in many regions.Although one way to preserve rural cultural landscapes involves establishing protected areas, management often forgets, or even restricts, the traditional rural activities that had contributed to the high conservation values recognised in these areas.In the present paper we applied a quantitative model to examine changes in rural cultural landscapes and in the socioeconomy of local populations following the establishment of a protected area. We formalised the relationship of dependence between landscape change and socioeconomy by means of multivariate ordination analysis and multiple regression calculation. The simple equation obtained shows the socioeconomic parameters that best account for change in the landscape and indicate their sign and importance. The results show that providing Regional Park protection status has not prevented the decline of traditional farming activities and, in turn, ecological succession has led to an intense shrub encroachment process. Such a change could be considered to be the result of a nature protection policy inspired by ideas of naturalness and wilderness. Our model also helps us to establish and formalise the dependence of the cultural landscape upon a socio-cultural system, which is currently undergoing rapid change, and brings us to consider the parameters of this change as indicators for management.  相似文献   
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