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Cotts RM 《Science (New York, N.Y.)》1993,261(5124):1063-1064
  相似文献   
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1. An experiment was conducted to examine the effectiveness of some extraction procedures at eliminating the antinutritional properties of jackbean to the broiler chicken. The most pronounced effects were observed in the base‐ and acid‐soluble protein fractions (BSP and ASP) which contained the bulk of the antinutritional factors.

2. The growth of chickens on all diets were significantly (P<0.05) reduced.

3. Examining the weights of broiler organs as a proportion of body weight showed a significant (P<0.05) decrease in the weight of the liver and an increase in the weights of the kidney, brain and pancreas.

4. Serum urea concentrations were elevated (P<0.05) in all groups receiving base‐soluble protein (BSP), acid‐soluble protein (ASP), defatted jackbean (DJB) and raw jackbean (RJB) diets. Enzyme activities were similarly elevated (P<0.01), but serum protein and albumin concentrations were depressed while uric acid was not influenced by dietary treatment.

5. Histopathological examination revealed several pathological lesions in organs of chicks fed on the BSP, ASP, DJB and RJB diets. The presence of lesions was less marked in the organs of chickens fed on diets containing base‐insoluble residue (BIR), acid‐insoluble residue (AIR) and ethanol‐extracted meal (EEM), while those given the aqueous heated jackbean diet did not show any pathological effects.  相似文献   

959.
1. Associations between body weight and rectal temperature were observed in female turkeys.

2. Turkeys with lower weights between 13 and 30 d of age tended to have higher temperatures.

3. Turkeys with lower weights at 7 d exhibited depressed body temperatures.

4. Higher or lower body temperatures may be associated with poorer performance depending on the time of appearance.  相似文献   

960.
1. Putative adipocyte precursor cells were isolated from the white adipose tissue of young broiler and layer chickens and cultured in vitro.

2. The cells from both sources were shown to have the characteristics of adipocyte precursor cells. On reaching confluence, lipoprotein lipase activity was induced and the cells from both strains accumulated large amounts of lipid in the presence of chicken serum.

3. Measurement of cell number over time in culture and calculation of cell doubling times showed that cells from broilers proliferated at a faster rate than those derived from layer‐strain chickens. This was the case whether primary or secondary cell cultures were used. Primary cultures of broiler cells had a doubling time of 22 h versus 39 h for layer cells.

4. The contribution of such a difference in proliferative rate to the differential rate of adipose tissue growth between broiler and layer strains observed in vivo is discussed.  相似文献   

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