tailieunhanh - Báo cáo khoa học: "Lighting during grow-out and Salmonella in broiler flocks"

Tuyển tập các báo cáo nghiên cứu về bệnh học thý y được đăng trên tạp chí Acta Veterinaria Scandinavica cung cấp cho các bạn kiến thức về bệnh thú yđề tài: Lighting during grow-out and Salmonella in broiler flocks. | Volkova et al. Acta Veterinaria Scandinavica 2010 52 46 http content 52 1 46 AVS ACTAVETERINARIA Scatand n SCANDINAVICA RESEARCH Open Access Lighting during grow-out and Salmonella in broiler flocks Victoriya V Volkova 1 J Allen Byrd2 Sue Ann Hubbard3 Danny Magee3 Richard H Bailey3 and Robert W Wills3 Abstract Background Lighting is used during conventional broiler grow-out to modify bird behaviour to reach the goals of production and improve bird welfare. The protocols for lighting intensity vary. In a field study we evaluated if the lighting practices impact the burden of Salmonella in broiler flocks. Methods Conventional grow-out flocks reared in the states of Alabama Mississippi and Texas USA in 2003 to 2006 were sampled 1 week before harvest n 58 and upon arrival for processing n 56 by collecting feathered carcass rinsate crop and one cecum from each of 30 birds and during processing by collecting rinsate of 30 carcasses at prechilling n 56 and post-chilling points n 54 . Litter samples and drag swabs of litter were collected from the grow-out houses after bird harvest n 56 . Lighting practices for these flocks were obtained with a questionnaire completed by the growers. Associations between the lighting practices and the burden of Salmonella in the flocks were tested while accounting for variation between the grow-out farms their production complexes and companies. Results Longer relative duration of reduced lights during the grow-out period was associated with reduced detection of Salmonella on the exterior of birds 1 week before harvest and on the broiler carcasses at the post-chilling point of processing. In addition starting reduced lights for 18 hours per day later in the grow-out period was associated with decreased detection of Salmonella on the exterior of broilers arriving for processing and in the post-harvest drag swabs of litter from the grow-out house. Conclusions The results of this field study show that lighting practices .