The influence of caecectomy on amino acid availability of three feedstuffs for ganders.

1. Experiments were conducted to assess the influence of caecectomy on amino acid availability (AAA) of three feedstuffs for goose. 2. Nine caecectomised and 9 intact Yangzhou ganders, 24 weeks old, were used in these experiments. Fish meal, soybean meal and cottonseed meal were used as the sole source of protein. The endogenous amino acid (AA) losses were evaluated by a nitrogen (N)-free diet method. The influence of caecectomy on apparent amino acid availability (AAAA) in fish meal, soybean meal and cottonseed meal was assessed in experiment 1 and true amino acid availability (TAAA) of three protein diets was determined in experiment 2. 3. Results showed that, in the soybean meal and cottonseed meal, the AAAA and TAAA of most AA determined by the intact ganders were higher than in the caecectomised ganders; in the fish meal, the AAAA and TAAA of most AA determined by the intact ganders were lower than in the caecectomised ganders. 4. Results of the present study suggest that the effect of caecectomy on AAA in geese was dependent on the feedstuff assayed, and it was better to use caecectomised poultry for AAA assessment.