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1.
1. White blood cell responses of broilers, turkeys and ducks were examined at regular intervals after being subjected to various degrees of food restriction. 2. Restricted-fed broilers showed increases in heterophil and basophil numbers, together with a corresponding decrease in lymphocytes. The heterophil/lymphocyte ratio was raised. There were no differences between broiler strains. 3. After only one week of feeding restricted diets, heterophils were significantly raised in selected and unselected 2-week-old ducks. At 21 weeks of age, those ducks receiving 50% of food required to achieve their ad libitum-fed body weight had raised heterophils. 4. Ducks receiving food to achieve 25% of ad libitum-fed birds produced a marked basophilia, but no heterophilia. 5. After two weeks of food restriction, turkeys responded with significant heterophil/lymphocyte ratios following two degrees of restricted feeding. 6. It was concluded that in some poultry, a heterophilia may be the response to mild to moderate stress but a basophilia may result after severely stressing birds.  相似文献   
2.
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   

3.
The rapid column method described, unlike AOAC method 7.056, determines both neutral ("crude") and total fat in canned pet foods, and uses nonflammable solvent mixtures and simple laboratory equipment. Neutral fat values are obtained by eluting the column with dichloromethane, whereas total fat values are determined by using dichloromethane-methanol (9 + 1). For 7 samples analyzed in triplicate, fat ranged from 2.9 to 10.8%. Neutral fat values by the dry column method were significantly lower (P less than 0.05) than were those by 7.056 (6.29 vs 6.49), although these differences were practically unimportant. Total fat determinations by the dry column method and by 7.056 yielded overall means of 7.40 and 6.49%, respectively. The 0.91% mean difference is significant (P less than 0.01) and represents a more complete extraction of polar lipids by the proposed method.  相似文献   
4.
Book reviews     
Amino Acids in Farm Animal Nutrition. Edited by J. P. F. D'Mello. 1994. 417 pp. £55.00 Wallingford, Oxon, CAB International. ISBN 0 85198 8814

Avian Hematology and Cytology. Terry W. Campbell. 1995. 104 pp. Illustrated. £48.00. Ames, Iowa State University Press. ISBN 0 8138 2970 4.  相似文献   

5.
1. The perfusion of livers with the vital dye trypan blue was performed to test for evidence of tissue hypoxia in 3 groups of young broiler chickens, namely, ascitic, hypoxia‐induced and controls.

2. Hepatocytes that stained with trypan blue were considered to be dead or dying before fixation and represented damaged cells.

3. The proportion of trypan blue‐stained hepatocytes in the livers of ascitic birds was slightly less than half that observed in the hypoxia‐induced birds but significandy more than the proportion of stained cells observed in control birds.

4. Liver damage in the ascitic birds was also assessed biochemically by an altered enzyme profile.

5. The study demonstrated that increased trypan blue uptake in the livers of ascitic birds reared at sea‐level may be the consequence of hypoxia stress caused by reduced oxygen utilisation.  相似文献   

6.
"This paper focuses upon interregional income divergence in Australia where a pattern very similar to that seen in the United States is discovered. Australian agricultural regions show downward divergence from the national mean per capita income and capital city regions show upward divergence."  相似文献   
7.
Cumulus-oocyte complexes from hormone-stimulated 3-4-week-old (n=43) and 6-7-week-old (n=12) prepubertal lambs were matured in vitro and incubated with unsorted, or X- or Y-spermatozoa separated with a high-speed cell sorter (SX MoFlo)frozen-thawed. Presumptive zygotes were then cultured to the blastocyst stage, and transferred to recipients fresh or after cryopreservation (frozen). Oocyte cleavage was higher (p <0.05) with unsorted (515/926, 55.6%) than X- or Y-spermatozoa (261/672, 38.8% and 229/651, 35.2%, respectively) and blastocyst formation (% zygotes) by Day 9 of in vitro culture was lower (p <0.05) for X- (102/261, 39.1%) than unsorted spermatozoa (249/515, 48.3%), but did not differ between Y-spermatozoa (103/229, 45.0%) and unsorted spermatozoa, or between X- and Y-spermatozoa (p >0.05). For fresh embryos, survival to term was 50.0% (3/6) for unsorted, 0.0% (0/6) for X- and 16.7% (1/6) for Y-spermatozoa-derived embryos (p >0.05), and for frozen embryos was 4.0% (2/50) for unsorted, 9.1% (2/22) for X- and 2.9% (1/34) Y-spermatozoa-derived embryos (p >0.05). Of the two lambs born from X-spermatozoa-derived embryos, one was female (50%), and from the two Y-spermatozoa-derived lambs, both were male (100%), demonstrating that lambs can be produced after the transfer of fresh and cryopreserved IVP embryos derived from prepubertal lamb oocytes and frozen-thawed sex-sorted sperm.  相似文献   
8.
Journal of Crop Science and Biotechnology - Even though there are abundant rice genetic resources, only a fraction is used in breeding programs leading to a narrow genetic base for improved...  相似文献   
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