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951.
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   

952.
49 of 102 sheep of one production herd, which had returned to oestrus once or twice within the 1985 breeding season, were treated twice in a nine-day interval with the PGF2 alpha analogue Cloprostenol "Jenapharm". 53 animals received an additional dose of 10 micrograms of Gonavet "Berlin-Chemie". A lambing rate of merely 15% was achieved by subsequent term-oriented artificial insemination. 31 sheep still in oestrus one day after term-oriented artificial insemination were served, bringing the lambing rate from synchronisation of oestrus and ovulation to 26% and the lambing result to 154%. Serving of the remaining sheep in 2 subsequent oestric cycles, on balance, yielded lambing rates and results of the remaining sheep in 2 subsequent oestric cycles, on balance, yielded lambing rates and results which were higher with significance than those recorded from untreated sheep in the same herd.  相似文献   
953.
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   
954.
133 samples of food were investigated for comparison of a recent commercially available 1-2 test (Biocontrol) with a cultural standard method (non-selective pre-enrichment in buffered peptone water, selective enrichment in Rappaport-Vassiliadis-medium and selenite brilliant-green mannitol enrichment broth, inoculation on two selective agars) for presence of Salmonella. The 1-2 test showed in positive results an accuracy ("sensitivity") of 94.7% and in negative results an assurance ("specificity") of 97.9% and is therefore considered suitable for detection of Salmonella contaminated food.  相似文献   
955.
1. Muscle fibre composition, capillary-fibre ratio and mitochondrial density of the Iliotibialis lateralis muscle were monitored during growth from the age of 8 weeks to sexual maturity (24 weeks) in sedentary birds and in birds subjected to regular treadmill exercise. 2. The Iliotibialis lateralis muscle consists almost exclusively of type IIA and IIB fibres with a small percentage of "unclassified" fibres. Over the 16-week period of growth there was no change in fibre composition but a marked fibre hypertrophy linked with a fall in the capillary-fibre ratio. Mitochondrial volume density increased with age but this was not significant. 3. Exercise significantly increased the IIA:IIB fibres ratio from 0.77 to 1.1 but had no significant effect on any other measured characteristics. 4. It is concluded that exercise at the intensity and duration employed (10-15 min daily, ca. 70-80% maximum oxygen consumption) has little effect on the growth and development of avian skeletal muscle although there was evidence of an increased oxidative capacity of the muscle.  相似文献   
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