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991.
1. Japanese quail hens were housed from 6 to 26 weeks of age in cages providing areas of 150, 180, 210 and 240 cm2/bird.

2. Body weight gain, age at 50% egg production, mortality, hen‐day egg production and food conversion values showed significant improvement with proportionate increase in cage space per layer.

3. Egg weight gradually increased with age but shell thickness was influenced neither by age of the hen nor by stocking density.

4. Yolk index and colour were superior in the lowest stocking density (more cage space) group; other egg quality traits and egg weight were not influenced by stocking density.

5. The albumen index, internal quality unit, yolk index and yolk colour values increased with age.  相似文献   

992.
1. Tissue accumulation of Cu from dietary additions of 0, 5, 10, or 20 mg/kg Cu as reagent grade Cu acetate and feed grade Cu carbonate was determined in day‐old chicks fed on conventional maize‐soyabean meal starter diets (5.41 mg/kg Cu as‐fed basis) for 3 weeks.

2. Average daily food intake, daily weight gain and food conversion were similar among treatments.

3. There were linear increases in plasma and liver Cu concentrations (P< 0.01) as dietary Cu increased.

4. Bioavailability of Cu as carbonate was 0.66 that of Cu in the acetate based on the multiple regression slope ratio of liver Cu concentration on added dietary Cu. Although responses for the two Cu sources did not differ significantly, the relative bioavailability of the Cu carbonate was similar (0.66 vs 0.68) to that obtained in an earlier study (Ledoux et al., 1991) with greater dietary Cu contents (150, 300 and 450 mg/kg) in which the slopes of the equations representing the two sources differed (P<0.05).  相似文献   

993.
Book reviews     
The Avian Egg: Chemistry & Biology, by R. W. Burley and D. V. Vadehra, 1989. v+472 pp. illustrated. New York. John Wiley & Sons. £66.70. ISBN 0–471–849952.

A Colour Atlas of Avian Anatomy, by J. McLelland. 1990. 127 pp. illustrated. London, Wolfe Publishing Ltd. £30. ISBN 0–7234–1575–7.

The Tropical Agriculturalist—Poultry, by A. J. Smith, 1990. vi + 218 pp. CTA/Macmillan, London. ISBN 0–333–52306–7.  相似文献   

994.
1. After 5 generations of selection on income minus food cost between 21 and 40 weeks of age (SECR), a correlated genetic improvement of 14.5% and 16.3% of the base population mean could be observed for income minus food cost between 41 and 60 weeks (IF60) in two lines of laying hens. The total responses up to 60 weeks amounted to 17.2% and 17.3% of the base population mean. A heritability of 0.30 for IF60 and a genetic correlation of 0.61 between SECR and IF60 were estimated.

2. The correlated relative genetic responses for 5 traits of the period between 41 and 60 weeks of age for the two lines were: 4.3% and 5.2% in egg number, 5.8% and 7.4% in egg weight, 8.4% and 10.8% in egg mass, ‐2.7% and ‐0.6% in body weight at 60 weeks, and ‐5.2% and ‐6.3% in food efficiency.

3. The estimated heritabilities of these 5 traits from the whole data set were 0.36, 0.75, 0.34, 0.71 and 0.17. The estimated genetic correlations between SECR and the same 5 traits were 0.30, 0.46, 0.61, ‐0.22 and ‐0.49.

4. A high genetic correlation of income minus food cost with egg weight and a low one with egg number were found in pullets, but the relationships were reversed in older hens.  相似文献   

995.
1. A metabolism trial was designed to investigate the role of methionine as a specific detoxifying agent of the condensed tannins present in faba beans (Vicia faba L.).

2. A 5 x 5 factorial approach was employed where 5 concentrations of dietary methionine were obtained (ranging from 3.9 to 12.15 g/kg diet dry matter) by the addition of DL‐methionine, and 5 concentrations of condensed tannins (ranging from 0.5 to 19.7 g/kg diet dry matter) by altering the ratio of tannin‐free and tannin‐containing faba bean hulls added to a basal diet.

3. The intake of condensed tannins had a significant, depressive effect on apparent available nitrogen (P< 0.001) and nitrogen corrected apparent metabolisable energy (AMEn ) (P< 0.001). There was no interaction between methionine and tannin (P>0.05). Thus the depressive effect of tannin was independent of methionine levels in the diet.

4. Methionine does not act as a specific detoxifier of faba bean condensed tannins.  相似文献   

996.
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   

997.
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   

998.
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   
999.
The experiment was conducted on 364 male Wistar rats of which 74 were included into the "zero" group and the remaining 290 were divided into 5 experimental groups, corresponding to the dietary protein levels of 4, 5, 10, 15 and 20%. The protein source in the diet was skim milk powder. The animals were fed individually and ad libitum. The experiment was performed between the 21 and 66 days of life of the rats and during this period, the animals in each group were successively killed to determine the nitrogen content in the body. Between the N content in the body and the body mass of rats from "zero" group, the relationship N0/W0 was determined. In each experimental group, two relationships were determined: --final nitrogen against final body mass--Nf/Wf --gain of nitrogen against gain of body mass--delta N/delta W. The derivatives of both functions were used for calculation of the daily gains of nitrogen (delta Nd) 1. According to the relationship Nf/Wf there was a similar significant increase of nitrogen content in the body in all groups with increasing the body mass, according to bc = 1.0413. The percentage of nitrogen in the body increased significantly only at dietary protein levels over 10%. 2. The rate of nitrogen gain in the gain of body mass according to delta N magnitude of was relatively constant in all groups (bc = 1). Thus, N-% in delta W was also relatively constant. N-% in the body gain increased significantly only at dietary protein levels over 10%. 3. Differences in the gains of nitrogen, as calculated by the derivative dNf/dWf and by d delta N/d delta W, showed in the first line in low-protein groups (on 4 and 5% protein) due to the error of estimation of the initial-N according to the equation N0 magnitude of W0. The mean relative error of estimation the initial-N was +/- 3% but in groups on 4 and 5% protein it charged the gain of N with 9-12% in spite of excluding from the relationship delta N magnitude of delta W rats with delta W less than 10 g. 4. Only when delta N greater than or equal to 1.3 g and delta W greater than or equal to 43, the error of estimation of delta N, did not exceed 3%.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
1000.
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   
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