tailieunhanh - Báo cáo khoa học: "Milk Fever Control Principles: A Review"

Tuyển tập các báo cáo nghiên cứu về bệnh thú y được đăng trên tạp chí y học General Psychiatry cung cấp cho các bạn kiến thức về ngành thú y đề tài: Milk Fever Control Principles: A Review. | Acta vet. scand. 2002 43 1-19. Milk Fever Control Principles A Review By T Thilsing-Hansen1 . Jorgensen1 and 5. 0stergaard2 1The Royal Veterinary and Agricultural University Department of Clinical Studies Cattle Production Medicine Research Group Frederiksberg and 2Danish Institute of Agricultural Sciences Department of Animal Health and Welfare Tjele Denmark. Thilsing-Hansen T Jorgensen RJ Ostergaard S Milk fever control principles A review. Acta vet. scand. 2002 43 1-19. - Three main preventive principles against milk fever were evaluated in this literature review and the efficacy of each principle was estimated from the results of controlled investigations. Oral calcium drenching around calving apparently has a mean efficacy of 50 -60 in terms of milk fever prevention as well as prevention of milk fever relapse after intravenous treatment with calcium solutions. However some drenches have been shown to cause lesions in the forestomacs. When using the DCAD dietary cation-anion difference principle feeding rations with a negative DCAD measured as Na K - Cl S significantly reduce the milk fever incidence. Calculating the relative risk RR of developing milk fever from controlled experiments results in a mean RR between and when rations with a negative versus positive DCAD are compared. The main drawback from the DCAD principle is a palatability problem. The principle of feeding rations low in calcium is highly efficient in milk fever prevention provided the calcium intake in the dry period is kept below 20 g per day. Calculating the relative risk RR of developing milk fever from controlled experiments results in a very low mean RR between 0 and daily calcium intake below versus above 20 g d . The main problem in implementing the low-Ca principle is difficulties in formulating rations sufficiently low in calcium when using commonly available feeds. The use of large doses of vitamin D metabolites and analogues for milk fever prevention is .