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1.
Behaviour of laying hens in a deep litter house   总被引:4,自引:0,他引:4  
1. Flocks of medium hybrid laying hens were housed in a modified deep litter system; the house was divided into 2, 3 and 4 pens in three successive years. Flock size was 300 or 370 and stocking density varied from 3.4 to 10.7 birds/m2. Higher densities used were above those recommended by the Ministry of Agriculture, Fisheries and Food (MAFF). 2. A random sample of 100 birds was identified with individual tags in each of the 9 flocks; regular observations using a scanning technique were made in each laying cycle to determine bird location and behaviour. 3. In all flocks the use of area by some individuals was uneven, that is, they were sighted in certain areas significantly more often than would have been expected by chance. The proportion of such individuals varied between flocks from 35 to 65%. Overall, birds spent more time on the slatted area than would have been expected from the area that it occupied. 4. A wide variety of different behaviour patterns was observed both on litter and on slats, but with foraging occurring more on litter and feeding more on slats. 5. Movement appeared to be constrained by crowding, because time spent in locomotion decreased in approximately linear fashion with increased stocking density. This provides support for MAFF recommendations of limits on stocking density in deep litter houses.  相似文献   
2.
The effects of intramuscularly administered medetomidine and butorphanol (MB), and medetomidine, butorphanol, atropine (MBA) on glomerular filtration rate (GFR) were determined in six dogs as measured by 99m-Tc-labeled diethylenetriaminepentaacetic acid (99mTc-DTPA) nuclear scintigraphy. Direct systolic, diastolic, and mean arterial blood pressures and heart rate were measured at regular time intervals before, during, and after GFR calculations. The mean GFR measurement following MB was significantly greater (4.44 ml/min/kg) than following MBA (3.82 ml/min/kg) or saline treatment (3.41 ml/min/kg). There was no significant difference between the mean GFR measurements following MBA injection and following saline injection. Diastolic and mean arterial pressures following MBA injection were significantly higher than the values recorded after either MB or saline alone. Heart rate following MB administration was significantly lower than that recorded for dogs receiving MBA or saline alone. The results of this study indicate that the administration of medetomidine in combination with butorphanol significantly increases total GFR in healthy dogs, while the administration of the combination of medetomidine, butorphanol, and atropine does not.  相似文献   
3.
Hege  Kippenes  DVM  Patrick R.  Gavin  DVM  PhD  Susan L.  Kraft  DVM  PhD  Ronald D.  Sande  DVM  MS  PhD  Russell L.  Tucker  DVM 《Veterinary radiology & ultrasound》2001,42(2):130-133
The pituitary gland was measured from transverse magnetic resonance T1-weighted images after Gadolinium administration in 96 dogs weighing from 13 to 45 kg. The measurements were done by hand with calipers. The mean (+/- standard deviation) pituitary gland height was 5.1 mm (+/-0.9 mm). The mean width was 6.4 mm (+/- 1.1 mm). The correlation coefficient between pituitary and brain measurements, between pituitary measurement and body weight, and brain measurements and body weight was 0.0 to 0.3. A hyperintense region was present on T1-weighted images in the center of the pituitary gland in 64% of the dogs. At necropsy the pituitary glands were grossly and histologically normal. No pituitary gland measurements were performed at necropsy.  相似文献   
4.
5.
Lactate Kinetics in veterinary Critical Care: A Review   总被引:3,自引:0,他引:3  
Elevation in blood lactate concentration, with or without accompanying metabolic acidosis, is a hallmark finding in patients with circulatory compromise, and is also consistently noted in other conditions affecting critically ill or injured individuals. Little is reported in a veterinary literature regarding lactate measurement in the emergency and critical care setting, despite impressive reports of the clinical usefulness of lactate measurement in people. The purpose of this article is to review lactate kinetics and the clinical utility of lactate measurement. Limitations to lactate evaluation will also be discussed.  相似文献   
6.
Objective: To evaluate the ability of capnography to document proper placement of nasoesophageal (NE) and nasogastric (NG) feeding tubes. This study was conducted in 3 phases. Phase I of this study was designed in order to test the efficacy of capnography to distinguish placement of a feeding tube in the alimentary tract versus the respiratory tract. Phase II was designed in order to document that carbon dioxide (CO2) could be measured through a polyvinyl chloride (PVC) feeding tube. Phase III was performed in order to evaluate the technique of continuous monitoring during insertion of the feeding tube into the esophagus and stomach as would be performed during a clinical‐tube placement. Design: Prospective study. Setting: Research laboratory. Animals: 24 adult dogs. Interventions: In Phase I, sedated dogs were instrumented with an intratracheal catheter and an 8 French feeding tube placed nasally into the distal esophagus and later advanced into the stomach. In Phase II, dogs were anesthetized and an 8 French feeding tube was placed down the endotracheal tube, then into the esophagus and later advanced into the stomach. In Phase III, sedated dogs were instrumented with an 8 French feeding tube inserted intranasally and then advanced to the level of the nasopharynx, distal esophagus and, lastly, the stomach. Fluoroscopy was used in order to determine location of the feeding tube. Measurements and main results: Phase I measurements included respiratory rate and CO2 from the trachea, esophagus, and stomach and pH of gastric fluid sample. Phase II measurements included respiratory rate and CO2 from the endotracheal tube, feeding tube in the endotracheal tube, feeding tube in the distal esophagus, and feeding tube in the stomach. Phase III data collection included respiratory rate and CO2 as the tube was passed through the nasal cavity, nasopharynx, esophagus and stomach. Phase I fluid samples were collected from 5 of the 9 dogs and had pH values from 1.68 to 4.20. In both phases, values for the respiratory rate and CO2 from the esophagus and stomach were 0 ± 0, significantly lower (P < 0.001) than the values from the trachea. In Phase II, there was no significant difference between the respiratory rates (P = 0.886) and CO2 (P = 0.705) readings obtained from the endotracheal tube compared to readings from the feeding tube in the endotracheal tube. In Phase III, there was a significant difference (P < 0.001) between the respiratory rates and CO2 readings obtained from the nasal cavity and the nasopharynx when compared to those readings obtained from the esophagus and stomach. Measurement of CO2 and respiratory rate resulted in a reading of 0 every time the feeding tube was in the esophagus or stomach. Conclusions: Capnography may be used in order to detect airway placement of NE and NG tubes.  相似文献   
7.
A six-year-old arabian stallion was admitted to The Ohio State University Veterinary Hospital for evaluation and repair of a comminuted fracture of the second phalanx. The horse developed impaired arterial oxygenation during surgey and pulmonary edema post-operatively. We postulate that impaired arterial oxygenation resulted from atelectasis of the dependent lung during annesthesia, and the pulmonary edema occurred following re-expansion of the atelectatic of the initiating cause of the edema, removal of excess lung water from the alveoli, and restoration of normal arterial oxygenation. The horse was fully recovered within 12 hours of initiation of clinical signs of respiratory compromise. The horse was fully recovered within 12 hours of initiation of clinical signs of respiratory compromise. This report describes re-expansion pulmonary edema due to reperfusion injury in a horse, treatment of the condition, and a possible explanation of the pathogenesis of this pulmonary pathology.  相似文献   
8.
Evaluation of Tissue Adhesive to Contain Axonal Regeneration in Horses   总被引:1,自引:1,他引:0  
Bilateral palmar and plantar digital neurectomies were completed in 10 horses (a total of 80 neurectomies) using one of three methods: (1) simple transection (guillotine method); (2) epineural capping; (3) n-butyl cyanoacrylate injected into the epineural sheath to act as a nerve sealant. Horses were regularly evaluated clinically for tenderness in and around the surgical site, as well as skin sensation at the coronary band in the heel region, during the 12-week course of the study. None of the surgical sites exhibited any signs of drainage or infection. Horses were then euthanatized, the nerve stumps were dissected from surrounding tissues, and the length and width of the tissue mass that had formed on the end of the nerve was recorded. Longitudinal and transverse sections of the nerve endings were examined histologically for numbers of proliferating axon sprouts (neuroma formation); whether the axons had penetrated the epineurium; degree of Schwann cell proliferation; degree of chronic inflammation; extent of foreign body reaction; extent of retrograde degeneration of the nerve bundles; and amount of fibro vascular proliferation. The proportion of legs exhibiting tenderness or heel sensation did not differ significantly between the three different treatments at any of the six different times they were examined. There was no difference between the three treatments in the length or width of the fibrous tissue scar on the ends of the nerves or in the number of sprouting axons from the ends of the nerves. Of 80 nerves examined, only two nerves were not confined to the epineurium. Both these nerves had been treated by simple transection. Statistically there was more chronic inflammation and foreign body reaction in the acrylic treated nerves, but no difference in Schwann cell proliferation or retrograde degeneration between the three treatments. There was slightly less fibrovascular proliferation in the transected nerves than in those subjected to epineural capping or acrylic, but the difference was not statistically significant. The use of the tissue adhesive n-butyl cyanoacrylate to prevent the continuous growth of axons after digital neurectomy seems to offer little advantage over more traditional methods of neurectomy.  相似文献   
9.
A 2.5 year old Appaloosa stallion with progressive weight loss and a heart murmur was diagnosed as having vegetative endocarditis of the right atrioventricular valves with a mass in the right atrium. The ultrasonographic appearance of the lesion was characterized by extreme reverberation. On postmortem examination, a 9 cm diameter thrombus was found within the right atrium and auricle, occupying approximately 80% of the chamber volume. Additionally, a lenticular abscess extended throughout the parietal cusp of the right atrioventricular valve. Histologic examination revealed that the lesions were septic with numerous gram positive cocci in short chains, suggestive of Streptococcus equi , and gram negative rods.  相似文献   
10.
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