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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.
In faeces and ileal digesta samples of 31 intact (INT) as well as 73 surgically differently prepared pigs bacterial fractionations and 2.6-diaminopimelic acid (DAP) estimations were carried out in order to calculate the bacterial N proportion in faeces N and digesta N after feeding various diets. Because of a high individual variability and the analytical variation width of the DAP/N-ratios no distinct influences of the fed diets could be found. The average DAP/N-values in the faeces (0.224) of INT pigs ranged in the same magnitude as in the digesta (0.0272) of ileorectostomized (IRA) pigs with open colon descendens (IRAo), where a digesta backflow is possible. Distinct lower DAP/N-ratios (0.0125 resp. 0.0043), however, were found in the digesta of pigs with ileo-caecal cannulae (IZB) or IRA pigs with closed colon (IRAg). On the base of various premises (N of the "bacterial fraction" C is only bacterial N; the DAP found in fraction A originates from intestinal bacteria adhering to feed particles) conducted calculations of the bacterial N proportions (in per cent of total N) led to the following data: Faeces of INT pigs: 43.0 ... 68.2 vs. 69.6 ... 89.0; digesta of operated pigs (except protein free diet) IRAo: 22.3 ... 57.0 vs. 46.2 ... 73.8; IZB: 17.0 ... 35.7 vs. 25.2 ... 53.6; IRAg (only 3 pigs): 23.6 vs. 24.2. The proportion of bacterial N in the digesta N of protein free fed IRAo pigs was 22.0 vs. 22.6%.  相似文献   
964.
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   
965.
966.
The clinical, radiographic, arthrographic, arthroscopic, and pathological findings of three horses with femorotibial joint injuries are presented. Overall diagnostic accuracy is improved when clinical signs, arthrography, and arthroscopy are combined. Treatment of these injuries remains limited. One horse was euthanized, and two were treated by stall rest after diagnosis. Of the two surviving horses, one became a successful breeding animal, and the other was unable to perform as a pleasure horse.  相似文献   
967.
968.
969.
970.
Equivalent salt solution series have been previously defined as solutions with combinations of sodium absorption ratio (SAR) and electrolyte concentration (Ec) producing the same extent of clay swelling in a given soil. The present study shows that there is a high (r2>0.96) positive correlation between log Ec and log SAR of equivalent salt solutions series, in the equation: where a1 and b1 are constants for each equivalent salt solution series for a given soil. Log a1 could also be represented as a linear function of b1 resulting in the equation: where a2 and b2 are constants for a given soil. Solving this equation using any given value of b1 yields the combinations of SAR and Ec which make up each equivalent salt solution series for a given soil. The relationship between log a1 and b2 for three soils from western United States, namely Waukena, Pachappa and Grangeville, was similar, with their combined data having a r2 value of 0.96. This indicated that a single set of equivalent salt solution series values could be used for these three soils which have different clay contents and clay mineralogy. Prediction of hydraulic conductivity decreases with Ec reduction at given values of SAR in red-brown and alluvial soils from southern Tasmania, using the equivalent salt solution series values for Waukena soil, showed similar patterns to measured values and also to those predicted using the equivalent salt solution values applicable to the respective Tasmanian soils. Thus, available data indicate that the same set of equivalent salt series could be applied to the five soils studied. If further testing shows that a single set of equivalent salt solutions values could be applied to all or large groups of soils, this would facilitate the application of the equivalent salt solution concept to predict salt solution flow in the field.  相似文献   
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