Evaluation of gossypol isomers and protein quality in cottonseed meal fed to broilers and turkeys /
Experiments were conducted to determine the biological availability of bound and free gossypol in cottonseed meals (CSM), establish the correlation between available gossypol and chick/poult performance, and to assess the relative toxicity of the (+) and (-) isomers of gossypol. Experimental diets w...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1999.
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| Subjects: | |
| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=733675581&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | Experiments were conducted to determine the biological availability of bound and free gossypol in cottonseed meals (CSM), establish the correlation between available gossypol and chick/poult performance, and to assess the relative toxicity of the (+) and (-) isomers of gossypol. Experimental diets were formulated on a digestible amino acid basis. Concentrations of total (+) and (-) isomers of gossypol were determined in lyophilized plasma and tissues. In Experiment 1, eight different CSM processed by different methods and differing in free gossypol were fed at 28% of the starter diet. Accumulation of total gossypol occurred at a faster rate in the liver versus other tissues. Within the range of free gossypol fed, tissue concentrations of gossypol increased linearly; whereas, proportions of gossypol isomers tended to plateau. In Experiment 2, an expander solvent CSM was included in starter and grower diets at 7, 14, 21 and 28%. Tissue concentrations of gossypol increased linearly as dietary free gossypol increased, and isomers reached steady state proportions that were a function of both gossypol intake and period of conscription. Ground seeds of two G. barbadense accessions and a G. barbadense cultivar differing in proportions of (+) and (-) isomers were used in a third experiment as sources of gossypol. Feed consumption decreased as dietary (-) gossypol increased. Concentrations of (+) and (-) isomers in plasma and tissues reflected conscription of individual (+) and (-) isomers of gossypol. A fourth experiment was similar to Experiment 2 using turkeys. Performance was not detrimentally affected by the inclusion of CSM. Tissue deposition and the proportions of gossypol isomers deposited were similar to broilers. Results from these experiments suggest that CSM at levels up to 28% of broiler starter diets (345 ppm Fe) or 21% in grower diets (270 ppm Fe) can support adequate performance when formulated on a digestible amino acid basis. Results indicate that toxic effects of gossypol in broilers are due primarily to the (-) isomer. Plasma concentrations of total gossypol < 10 ug/mL appear to be well tolerated by both broilers and turkeys. |
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| Item Description: | Vita. "Major Subject: Poultry Science". |
| Physical Description: | xv, 159 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilm Inc. |
| Bibliography: | Includes bibliographical references (leaves 148-158). |