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961.
1. The feeding value of new low β‐N‐oxalyl‐amino‐L‐alanine (BOAA) lines of Lathyrus sativus (lathyrus) and the benefits of dehulling the seed or of pre‐adapting chicks to lathyrus‐based diets were examined in several experiments.

2. Chicks fed on diets containing 400 g/kg of the low (1.3 g BOAA/kg seed) and medium (2.2 g BOAA/kg seed) BOAA lines did not differ (P>0.05) in weight gain (WG) or in apparent fat and protein digestibilities compared to birds fed on a wheat‐based diet.

3. Consumption of 600 g low BOAA lathyrus/kg diet caused a slight, but significant (P< 0.05), decrease in WG. Food efficiency decreased as the amount of dietary lathyrus was increased, suggesting that lathyrus may contain an antinutritive factor(s) other than BOAA.

4. Removal of the hull (70 g hull/kg seed) from the seed did not affect chick performance (P> 0.05).

5. Pre‐adapting chicks for 7 d to diets containing up to 600 g medium line lathyrus/kg diet did not reduce the detrimental effects of the lathyrus.

6. Although dehulling and pre‐adaptation of chicks to lathyrus were not beneficial, the low and medium lines of lathyrus tested show potential for use in chick diets up to at least 400 g lathyrus/kg diet.  相似文献   

962.
Book reviews     
Recent Advances in Turkey Science. Edited by C. Nixey and T. C. Grey, Poultry Science Symposium Number 21. London, Butterworths, ISBN 0 408 00971 3

Egg and Eggshell Quality. Sally E. Solomon, 1991, 149 pp., illustrated. London, Wolfe Publishing Ltd., £35.00, ISBN 0 7234 1647 8.

Aleen Cust, Veterinary Surgeon, Britain's First Woman Vet. Connie M. Ford, 1990, 109 pp., £5.99, Bristol, Biopress Ltd., The Orchard, Clanage Road, ISBN 0 948737 11 5.

Avian Incubation. Edited by S. G. Tullett, 1991, xiv + 335 pp., illustrated. London, Butterworth‐Heinemann. £00.00, $00.00. ISBN 0–7506–1002–6.

A Colour Atlas of Diseases & Disorders of the Domestic Fowl & Turkey. Edited by C. J. Randall, second edition, 1991, 175 pages, 432 illustrations in colour. London, Wolfe Publishing Ltd, £35, ISBN 0723416281.  相似文献   

963.
The literature contains about 500 cases of equine leucosis, though the reports are deposited in a great number of journals and vary considerably concerning particular topics. During the last years there has been a remarkable increase of publications about this syndrome in the equine. The clinical leucosis key recommended by us has been confirmed in principle considering the latest literature. In about 70 individual symptoms which can be clinically observed in equine with leucosis 11 can be considered as main symptoms because of their frequency; they are again classified in primary (lymph node tumours including splenomegaly--loss of condition, weakness--cachexia, weight loss, periphery oedema), secondary (anorexia, inappetence--fever--paleness of mucous membrane--anaemia--tachycardia) and accessory (incoordination--tachypnoea, dyspnoea--apathy, lethargy) main symptoms. Furthermore in future it will be necessary to take into more consideration the symptoms "recurrent colic" and "hydrothorax" within differential diagnosis. The main symptom "incoordination" (ataxia, asynergy, paresis, paralysis) is used by us more precisely only in case of impairment of nervous system by neoplastic infiltrations and does not signify as possible symptoms of general physical weakness, for example faltering, staggering, tumbling or lameness. The morphological classification follows further on our previous recommendation. There exist generalized forms with tumour infiltrations in abdominal and in thoracic cavity as well as especially in peripheral lymph nodes. On the other hand there are characteristic manifestations in certain regions of the body, which establish distinctly the clinical symptomatology. They are marked as regional multicentric forms with the main localizations "mediastinal", "splenic", "mesenteric" or "intestinal".(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
964.
965.
Rabies diagnosis in western Canada, 1985-1989   总被引:1,自引:0,他引:1       下载免费PDF全文
The results of laboratory examination of 20460 specimens for the diagnosis of rabies by the standard fluorescent antibody and mouse inoculation tests over a five year period are presented. Specimens were received from British Columbia, Alberta, Saskatchewan, Manitoba, and the Yukon and Northwest Territories. Of those examined, 9.96% were positive. The main reservoirs of rabies were skunks, bats, and foxes. During this observation period a rabies epizootic occurred in skunks in Saskatchewan. When both tests were performed, the fluorescent antibody test was found to agree with the mouse inoculation test in over 99% of cases.  相似文献   
966.
967.
968.
Trimethoprim-sulfadoxine (TMPSDX) and two formulations of oxytetracycline (OTC) were examined for their prophylactic efficacy in feedlot calves when given by intramuscular injection on arrival at a large commercial feedlot. The study included 2,112 high-risk feeder calves that developed disease early in the feeding period. Both formulations of OTC reduced bovine respiratory disease morbidity during the first two weeks on feed and for the entire feeding period by 15-19% (p<0.05), and they also reduced all fatal fibrinous pneumonia by 67% and 84% (p<0.05). All three drugs significantly reduced all fatal disease in animals first treated during the second week on feed, but not for the overall feeding period. Oxytetracycline with 2-pyrrolidone reduced the incidence of all fatal disease by 44% (p<0.05) during the entire feeding period. The case fatality risk for calves first treated during the second week on feed was lower (p<0.05) in the TMPSDX group and in the OTC with polyvinyl-pyrrolidone group.  相似文献   
969.
The methods used in a large field study which investigated the health and productivity of Ontario beef breeding herds are described. Beginning in the calving season of 1986, 180 breeding herds on 170 randomly sampled farms were followed for a two year period, using producer records and annual farm visits.

The response (cooperation) rate among the eligible producers initially contacted was 70%. Approximately two-thirds of producers maintained individual animal records, primarily calving season records. Approximately 40% recorded disease occurrences.

The advantages, disadvantages, and interpretation of “on-farm” observational studies are discussed.

  相似文献   
970.
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