Question: what year is the animal slaughter act that we follow
[{'answer': 'August 27 , 1958', 'provenance': [{'wikipedia_id': '2872543', 'title': 'Humane Slaughter Act', 'start_paragraph_id': 1, 'start_character': 224, 'end_paragraph_id': 1, 'end_character': 240, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '2872543', 'title': 'Humane Slaughter Act', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 1540, 'bleu_score': 0.9917524012752491, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 15643183619881874835}, 'section': 'Section::::Abstract.'}]}]