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Breeding birds

83. We found no evidence that breeding hens were prone to lameness.

84. Large breeding stags which are used as grandparent stock to influence the genetic pool have the greatest potential for leg disorder. There are very extreme types with a high pre-disposition to lameness. Very few breeding stags are taken to excessively heavy weights but those we saw had unnatural gaits and some had difficulty in walking.

85. Breeding policies adopted across the world make it inevitable that a small number of grandparent stags will be reared to extreme weights and size. These birds should not be allowed to suffer. We know of evidence that the older, heavy breeding stags may be affected by severe degenerative joint disease and experience pain during movement as a result. Further research is required to establish whether or not these lesions occur in younger breeding stock, particularly males; and to determine the potential for suffering and whether or not the lesions are related to excessive weight or abnormal conformation. In the meantime, management practices must seek to minimise the occurrence of leg pain in heavy stags by careful selection, vigorous culling and reduction of the energy intake levels. Culling should occur immediately a problem is manifest and breeding companies must not continue to collect semen once a stag shows signs of suffering.

86. We believe that some grandparent stags have been taken beyond the limit of acceptability and that it would not be appropriate to continue to select for increased weight without first improving leg strength.

Recommendations

87. We recommend research to establish at what point leg problems, particularly in heavy breeding stags, result in pain or other aspects of poor welfare and into the predisposing factors and pathological lesions which may be associated with leg disorders.

88. "Shaky leg syndrome", which appears to be the commonest leg disorder of turkeys, is not characterised by any distinctive pathology. The condition requires further research.

89. Farmers and breeding companies must rigorously cull birds which are suffering as a result of leg disorders.

90. Heavy grandparent birds should not be kept to advanced ages.