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991.
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Book reviews     
Manipulation of the Avian Genome. Edited by R. J. Etches & A. M. V. Gibbins, 1993. 322 pp., illustrated in colour. Boca Raton, FL, CRG Press. ISBN 0–8493–4216–3.

Proceedings of the 8th European Symposium on Poultry Nutrition. Edited by The Organizing Committee, 1992. 373 pp. Milan, Italy. World's Poultry Science Association.  相似文献   

994.
1. The effect of pelleting process and Trichoderma viride enzymes (TVE) addition on apparent metabolisable energy, corrected for nitrogen balance (AMEn) and on productive value of practical diets containing 40 and 45% of three different barley cultivars and one wheat were studied in poultry.

2. The effect of the pelleting process on AMEn was inconsistent and was dependent on the cereal included and the addition of enzyme.

3. The growth trial showed a significant effect of enzyme addition to pelleted diets over the whole growth period (0 to 42 d). Addition of TVE improved weight gain and food efficiency by 1.3% and 2.9%, respectively and decreased food intake by 1.6% between 0 and 22 d. In the finisher period (23 to 42 d) TVE improved efficiency by 2.8% and reduced food intake by 2.9%.

4. The incidence of sticky droppings was related to the viscosity of barley used, and enzyme supplementation reduced it. Both pelleting and enzyme addition increased dry matter content of excreta.

5. At the end of the experiment, 14 animals per treatment were slaughtered and carcass yield, viscera weight and abdominal fat were determined.  相似文献   

995.
1. Variations in the concentration of plasma cholesterol available to the developing oocyte over a three week period in Gallus domesticus are described.

2. There are small changes in concentration between weeks for individual birds, but no changes between consecutive days within weeks or times within days.

3. It is recommended that future attempts to assess the relationship between variation in blood and yolk cholesterol concentrations estimate blood cholesterol concentration from two samples taken a week apart.  相似文献   

996.
1. Three experiments were performed to study the effects of amino acid imbalance on the growth of genetically lean (LL) or fat (FL) male chickens from 28 to 42 d of age. In experiment 1, five concentrations of digestible lysine were compared (4.75, 6.75, 7.75, 8.75 and 9.75 g/kg). In experiment 2, four concentrations of digestible arginine were compared (6.53, 7.69, 8.84 and 10.0 g/kg). In experiment 3, three diets were compared: a high‐protein diet (189 g CP/kg), a low‐protein diet containing added essential amino acids (EAA) (144 g CP/kg) and this low‐protein diet supplemented with 40 g/kg of non‐essential amino acids (NEAA) (glutamic acid + aspartic acid).

2. LL birds exhibited a lower growth rate than the FL when the diet was deficient in either lysine or arginine. Plotting weight gain against lysine or arginine intake suggested that most of this effect was caused by variations in food intake.

3. When protein gains (body or total proteins) were plotted against lysine or arginine intake, LL chickens appeared more efficient than FL chickens.

4. Similar growth rates, although slightly lower in FL, were obtained with low‐ and high‐protein diets. However, NEAA supplementation of the low‐protein diet reduced adiposity of LL and did not modify that of FL. Increasing crude protein content (all amino acids) was more effective than NEAA supplementation in decreasing the adiposity of both lines.  相似文献   

997.
1. Diets containing a freeze‐dried tannin extract from faba beans (Vicia faba L.) at concentrations of 0, 8 and 16 g/kg were fed to growing chicks and rats.

2. Chicks fed on the tannin‐containing diets exhibited a high mortality and significant decreases in body‐weight as well as lower food intakes and higher food intake:weight gain ratios (P<0.01). In rats there was no mortality but the growth and food intake were adversely affected (P< 0.05).

3. Histological changes occurred in the ileal mucosa of chicks. Atrophy and shortening of villi with distortion of their architecture were observed. Similar histological disorders but less pronounced were also found in rats.

4. Histopathology of the liver of both chicks and rats showed an hydropic degeneration of hepatocytes, clearly more severe in the former than in the latter.  相似文献   

998.
Sword MA  Garrett HE 《Tree physiology》1994,14(10):1121-1130
At germination, container-grown shortleaf pine seedlings were inoculated with Pisolithus tinctorius (Pers.) Coker & Couch or left uninoculated, and both groups were fertilized semiweekly with a modified Hoagland's solution supplemented with 0 or 0.4 mM boric acid. After 12, 16 and 24 weeks, seedling root tissue was analyzed for ectomycorrhizal colonization, phenolic concentration and phenoloxidase activity. In addition, phenoloxidase activity was assayed in P. tinctorius that had been cultured in a liquid medium containing boric acid. Inoculation with P. tinctorius increased the root phenolic concentration of 16- and 24-week-old seedlings, and increased root phenoloxidase activity in 12-, 16- and 24-week-old seedlings. Fertilization with boric acid reduced the phenolic concentration of P. tinctorius ectomycorrhizae after 24 weeks. Although boric acid fertilization did not affect the phenoloxidase activity of 12-, 16- and 24-week-old inoculated roots, or that of 16- and 24-week-old uninoculated roots, it increased the phenoloxidase activity of P. tinctorius grown in vitro and 12-week-old uninoculated roots. We conclude that boric acid fertilization influences the phenolic relations of the shortleaf pine-P. tinctorius ectomycorrhizal association, possibly through a boric acid-induced increase in phenoloxidase activity.  相似文献   
999.
1000.
A novel concept for performing stoichiometric and catalytic chemical transformations has been developed that is based on the limited miscibility of partially or fully fluorinated compounds with nonfluorinated compounds. A fluorous biphase system (FBS) consists of a fluorous phase containing a dissolved reagent or catalyst and another phase, which could be any common organic or nonorganic solvent with limited or no solubility in the fluorous phase. The fluorous phase is defined as the fluorocarbon (mostly perfluorinated alkanes, ethers, and tertiary amines)-rich phase of a biphase system. An FBS compatible reagent or catalyst contains enough fluorous moieties that it will be soluble only or preferentially in the fluorous phase. The most effective fluorous moieties are linear or branched perfluoroalkyl chains with high carbon number; they may also contain heteroatoms. The chemical transformation may occur either in the fluorous phase or at the interface of the two phases. The application of FBS has been demonstrated for the extraction of rhodium from toluene and for the hydroformylation of olefins. The ability to separate a catalyst or a reagent from the products completely at mild conditions could lead to industrial application of homogeneous catalysts or reagents and to the development of more environmentally benign processes.  相似文献   
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