A test for photorefractoriness in high‐producing stocks of laying pullets     

T. R. Morris  P. J. Sharp  E. A. Butler 《British poultry science》1995,36(5):763-769

1. Pullets of 2 high‐producing commercial stocks (both brown‐egg layers) were exposed to 5 different lighting patterns between 18 and 72 weeks to test the hypothesis that photoperiods used in commercial lighting programmes early in the laying year may be unnecessarily long and, by accelerating the development of photorefractoriness, may contribute to the decline in egg production observed after the initial peak. Two rooms of 288 pullets were allocated to each treatment.

2. The rate of lay observed with a Step‐Up treatment which gave increases in photoperiod from 8L:16D at 18 weeks to 15L:9D at 27 weeks of age was not significantly different from that of treatments which held the birds on 11L:13D during peak egg production but gave increments up to 15L:9D later in the laying year.

3. A control group maintained on 11L:13D from 20 to 72 weeks laid 295 eggs per bird housed and a further group held on 8L:16D from 0 to 72 weeks laid 284 eggs per bird. These yields were lower than the Step‐Up treatment (299 eggs) but show the potential of modern hybrid stocks to lay prolifically even without light stimulation.

4. It is concluded that the stocks tested in this experiment showed no advantage when given lighting programmes in the first laying year which were designed to minimise the adverse effects of photorefractoriness.  相似文献   

Laboratory Diagnosis of Enteropathogenic Escherichia coli in Calves          下载免费PDF全文

Ogilvie TH  Curtis RA  Butler DG  Macleod GK 《The Canadian veterinary journal. La revue veterinaire canadienne》1982,23(10):307

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Resume of fracture healing.     

H C Butler 《The Veterinary clinics of North America》1975,5(2):147-156

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NSAIDs     

Dr Anthony Blikslager DVM  PhD  DACVS  Associate Professor  Dr Sam Jones DVM  PhD  DACVIM  Associate Professor 《Journal of Equine Veterinary Science》2005,25(3):98-102

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Scientific training     

William E. Jones DVM  PhD 《Journal of Equine Veterinary Science》2005,25(7):95-321

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Effects of intravenous sodium bicarbonate and sodium acetate on equine acid-base status     

Kevin Kline PhD  Leonard P. Frey PhD  Jonathan H. Foreman DVM  MS  Joseph T. Lyman DVM  MS 《Journal of Equine Veterinary Science》2005,25(8):349-354

Changes in blood gases, pH, and plasma electrolyte concentrations in response to intravenously infused sodium bicarbonate (NaHCO₃) and sodium acetate (NaCH₃CO₂) solutions (1.34 mEq/mL) in 5 light breed mares were investigated. Jugular venous blood samples were collected before and after completion of the infusions in 20-minute intervals for 200 minutes. Infusion of sodium bicarbonate and sodium acetate caused significant (P < .00l) increases in blood pH and bicarbonate ion concentration that persisted throughout the collection period. The elevation in blood pH and bicarbonate ion concentrations was greater (P < .01) for sodium bicarbonate than for sodium acetate immediately after the completion of the infusions but was not different (P > .05) thereafter. There were significant reductions (P < .01) in plasma-ionized calcium and potassium after infusion of both sodium bicarbonate and sodium acetate. This study found that significant metabolic alkalosis in horses and corresponding shifts in electrolyte concentrations can be induced by intravenous infusion of solutions of either sodium bicarbonate or sodium acetate, and they persist for at least 3 hours. These data show that the short-term elevation in pH and bicarbonate ion concentration is momentarily higher after infusion of sodium bicarbonate. This is likely due to the direct infusion of bicarbonate ions in the sodium bicarbonate treatment, such that further metabolism is not required to be effective. However, the longer-term alkalosis did not differ between isomolar solutions of sodium bicarbonate and sodium acetate.  相似文献   

Equine infectious anemia in mules, donkeys, and horses: Epidemiologic studies in the different geographic regions of Turkey   总被引：1，自引：0，他引：1  

Veysel Soydal Ataseven DVM  PhD  Handan Hilal Arslan DVM  PhD 《Journal of Equine Veterinary Science》2005,25(10):439-441

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How to perform transvenous electrical cardioversion in horses with atrial fibrillation   总被引：1，自引：1，他引：1  

M. Kimberly J. McGurrin DVM  Dipl ACVIM  Peter W. Physick-Sheard BVSc  MSc  FRCVS  Daniel G. Kenney DVM  Dipl ACVIM 《Journal of Veterinary Cardiology》2005,7(2):109

Electrical cardioversion of atrial fibrillation is a well-established technique for restoration of sinus rhythm in humans. While transthoracic cardioversion is more commonly used, transvenous electrical cardioversion (TVEC) has been reported as having higher efficacy at substantially lower energy levels. In horses, treatment of atrial fibrillation has essentially been limited to the administration of quinidine salts either orally or intravenously. TVEC provides an alternative to quinidine salts, especially for those animals in which quinidine is neither effective nor tolerated. The present report details this technique in horses, discusses possible complications of the procedure, and provides guidance for successful outcome. Still and video images are used to illustrate details with regard to TVEC techniques in horses. Please view supplemental material for the videos.  相似文献   

A retrospective evaluation of transthoracic biphasic electrical cardioversion for atrial fibrillation in dogs     

Janice M. Bright BSN  MS  DVM  Dipl ACVIM  Julie M. Martin DVM  MS  Dipl ACVIM  Khursheed Mama DVM  Dipl ACVA 《Journal of Veterinary Cardiology》2005,7(2):85-96

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MAGNETIC RESONANCE IMAGING FINDINGS OF PRESUMED CEREBELLAR CEREBROVASCULAR ACCIDENT IN TWELVE DOGS     

J. F. McConnell  BVM&S  DVR  DipECDVI  Cert. SAM MRCVS    L. Garosi  DVM    S. R. Platt  BVM&S 《Veterinary radiology & ultrasound》2005,46(1):1-10

The magnetic resonance imaging (MRI) findings of presumed cerebrovascular accident in 12 dogs are described. Fourteen lesions were seen, commonly (11 of 14) within the gray matter of the cerebellar hemispheres or vermis. Thirteen lesions were hyperintense on T2-weighted images (in 11 dogs) and one was hypointense. Eleven of 14 lesions were within the region supplied by the rostral cerebellar artery or one of its main branches and there was no, or minimal, mass effect. Contrast enhancement was only seen in six lesions and was mild in all. Gradient-echo images provided additional information in two dogs. The appearance of infarction in dogs with diffusion-weighted images (DWI) is similar to that in humans, and provided supportive evidence for the diagnosis of infarction in five dogs. The use of gradient-echo and DWI is recommended for the evaluation of suspected cerebrovascular accidents in dogs. Six of the 12 affected animals were spaniels or spaniel crosses, suggesting a possible breed predisposition.  相似文献