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81.
Objective To measure the plasma cortisol response in lambs castrated and docked by three different methods (ring castration and tail docking, ring and clamp castration and tail docking; ring and clamp castration and ring tail docking) for 4 h after treatment.
Design A physiological study with controls.
Procedure A rubber ring was applied to the scrotum. Then the castration clamp was placed, distal to the ring, on each spermatic cord such that there was no overlap of the crush lines.
Results There were no differences in the cortisol secretion of the lambs castrated and tail docked by the ring only and by the ring plus castration clamp methods. Using the castration clamp in addition to the ring on the tail had no effect on cortisol secretion.
Conclusions Using the castration clamp did not appear to reduce the cortisol response to ring castration and docking, as demonstrated elsewhere, because the areas of uncrushed tissue between the two castration clamp crush lines allowed nociception from ischemic scrotal tissue to be transmitted cranially via undamaged nerve fibers.  相似文献   
82.
Natural disease outbreaks of erysipelas and fowl cholera occurred in several lines of turkeys maintained for genetic studies. There were line differences in mortality during both outbreaks, suggesting that there is genetic variation in resistance to these diseases. A line developed by selection for increased egg production had a higher mortality rate from fowl cholera than did the randombred control line from which it was developed. Both the egg line and its control line had a lower mortality rate in the erysipelas outbreak than did a line selected for increased growth rate. Both diseases induced high mortality in a line selected for increased growth.  相似文献   
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Intracameral injection of tissue plasminogen activator has been suggested as a means of hastening the clearance of blood from the anterior chamber and reducing the risk of synechia and fibrotic membrane formation in horses with hyphaema. The following report describes a case of ocular trauma in which intracameral injection of tenecteplase (TNK), a new‐generation plasminogen activator, resulted in rapid resolution of hyphaema and successful outcome. However, a large dose (1 mg) was administered and may have been associated with retinopathy and keratopathy. TNK may be an effective treatment for equine hyphaema and further controlled clinical or experimental studies are required to determine its efficacy and safety profiles.  相似文献   
87.
Castration is an ancient husbandry procedure used to produce docile cattle for draught work, to reduce unwanted breeding, and to modify carcass quality. All the physical methods used to castrate cattle have side-effects and cause pain. The plasma cortisol response to castration using Burdizzo clamps and, by inference, the acute pain experienced, is less than that caused by surgical, rubber-ring or latex-band castration. The cortisol response may be influenced by the age of the animal castrated, but this has not been well defined. Local anaesthesia virtually eliminates the cortisol response, and thus the acute pain, caused by rubber-ring or latex-band castration, but needs to be combined with a systemic analgesic such as the non-steroidal anti-inflammatory drug ketoprofen to eliminate the cortisol response to Burdizzo or surgical castration. When used alone, ketoprofen sometimes reduces the cortisol response to Burdizzo or surgical castration but may need to be accompanied by local anaesthesia to eliminate the pain-induced behaviour seen during the castration process itself. Thus, pharmacological methods are available to virtually eliminate the acute pain experienced by calves during the 12 h following castration. The use of these methods is an additional cost for farmers and may be limited by the availability of drugs for farmers to use and the scarcity of veterinarians in farm animal practice.  相似文献   
88.
Weed management involving the time of hilling and various herbicide applications was compared. The best weed management program consisted of EPTC (S-ethyl dipropylcarbamothioate) at 3.3 kg ai ha-1 preplant incorporated, followed by metribuzin [4-amino-6-(1,1-dimethylethyl)-3-(methylthio)-1,2,4-triazin-5(4H)-one] at 0.6 kg ai ha-1 applied delayed pree-mergence, or delayed preemergence applications of metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl) acetamide] plus linuron [N’-(3,4-dichlorophenyl)-N-methylurea] (2.2 + 1.1 kg ai ha-1) or metolachlor plus metribuzin (2.2 + 0.6 kg ai ha-1) regardless of the time of hilling. Alternatively, postemergence applications of sethoxydim [2-[1-(ethoxyimino) butyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one] plus metribuzin plus crop oil concentrate at 0.2 plus 0.6 kg ai ha-1 plus 1.2 L ha-1 provided excellent season-long weed control regardless of the time of hilling. However, potato yield was reduced in 1 of 2 years by this treatment. Preemergence herbicides applied immediately after planting followed by an early hilling at ground cracking did not provide season-long weed control. The cultivar Atlantic was a better competitor with weeds than Russet Burbank in 1 of 2 years.  相似文献   
89.
A captive male Adelie penguin (Pygoscelis adeliae), wild caught in 1976, died unexpectedly. Necropsy revealed cholangiocarcinoma with metastases to lung, pancreas, mesentery, and cloaca, the first known case of a penguin hepatic tumor.  相似文献   
90.
SUMMARY Lice were collected from 71 flocks detected as Infested at market Inspection in 1990 and 1991, from 16 flocks where resistance was suspected and from 31 flocks from Kangaroo Island. Susceptibility to cypermethrin was measured by a treated surface technique and survival of lice at 5 ppm or greater was taken as an indication of resistance. The prevalence of resistance was 34% in louse populations from the market inspection sample, 50% in flocks in which resistance was suspected and 68% in flocks from Kangaroo Island. Most resistance factors were in the range 1 to 20 although one louse population with a resistance factor of 91 was found on Kangaroo Island.  相似文献   
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