Recipient Organization
IOWA STATE UNIVERSITY
S. AND 16TH ELWOOD
AMES,IA 50011
Performing Department
Veterinary Medicine
Non Technical Summary
Rickets and osteomalacia are the disease names associated with metabolic bone disease in growing animals and adult animals, respectively. Metabolic bone disease has not garnered much attention in the last few decades because most nutritional programs provide adequate calcium, phosphorus and vitamin D. During the 2010 winter/spring, the Iowa State University Veterinary Diagnostic Laboratory (ISU-VDL) investigated causes of sudden death in nursery and finisher pigs throughout the Midwest. The cause was associated with vitamin D deficiency in several cases. This problem, in part, was linked to a specific nutrient supplier that ultimately ended up in a USDA mandated feed recall. However, there have been multiple cases during this investigation and thereafter that were not associated with the particular feed company that was identified in the feed recall. Because of this finding, we hypothesize that there are pig populations throughout different productions stages marginally to severely deficient in serum and tissue vitamin D. As diagnosticians, we understand that clinical signs of vitamin D deficiency have been relative rare in the last 20 years. Albeit vitamin D deficiency is an old disease, there have been many changes in swine industry nutrition leading up to this point. For example there have been extensive use of distiller dried grains (DDGs) in recent years, the implement of phytases reducing the amount of dicalicum phosphate that is required in rations, the presence of extremely elevated mycotoxins and the use of mycotoxin binders. Furthermore, genetics changes and recent down turns in the swine market have directed many producers and nutritionists to find economic savings in the feed. All factors considered, as a swine industry we really do not have an understanding of these changes that are affecting pigs on a metabolic basis as it relates to the axial skeleton and disease. Recent investigation in human medicine indicates that vitamin D is much more active than just in calcium metabolism. Vitamin D has an influence on immunologic function in humans and probably animals. The intent of this proposal is to further investigate vitamin D levels in pigs at different stages of production. Serum samples submitted to the ISU-VDL will be selected based on age and production setting and assayed for vitamin D concentration. Thereafter, the submitting veterinarian will be contacted and questioned concerning 1) type of barn (curtain sided, tunnel, etc), 2) lighting (incandescent or other), 3) disease issues (in particular lameness and sudden death), 4) feed manufacturer, and 5) will be asked to obtain/submit a feed sample along with computer based formulation of the feed. Selected feed samples will be analyzed and compared to desire formulation specification. We believe that we will observe multiple situations in different stages of production in which pigs are deficient in Vitamin D and hopefully will find a link to explain this that could be further evaluated in the future.
Animal Health Component
75%
Research Effort Categories
Basic
25%
Applied
75%
Developmental
(N/A)
Goals / Objectives
Assess serum vitamin D levels in pigs from different age groups across different stages of production (Finishing, nursery, gestation) to determine if there are subclinical or clinical deficiencies occurring within the industry. To determine if there are common environmental links in deficient groups of pigs by contacting the attending veterinarian. Determine feed status of vitamin D in deficient cases aiming for 10 feed sample each from finishing pigs, nursery pigs, and gestating animals.
Project Methods
We plan to obtain the serum samples needed for this project from split samples of swine serum samples that are submitted to the ISU-VDL for routine serologic examination. The plan is to obtain a serum sample from at least 6 animals in a submission and divide the phases sampled into nursery, finish and gestation. Approximately 30 nursery, 30 finish, and 30 gestating sites will be sampled throughout the year. Of the 30 samples from the 3 different phases we will obtain 15 samples from the summer/fall season and 15 from the winter/spring season to evaluate any differences in the amount of daylight exposure there is to serum vitamin D status. The submitting veterinarian in each the selected cases will be contacted and questions about the facilities, lighting, feeding, and disease. In sites with a low or marginal serum vitamin D finding, a sample of the diet that the pigs were consuming when the serum samples were taken will also be obtained for evaluation of the vitamin D status in 10 of the submissions from nursery, 10 from finish and 10 from gestating sites. Some of the questions with the cases of vitamin D deficiency that have been investigated in 2010 include is vitamin D3 present in the feed, is vitamin D2 being used instead of vitamin D3, if vitamin D3 is present in the feed is it actively being absorbed, are mycotoxins present in the feed interfering with absorption of vitamin D, are mycotoxin binders being used interfering with vitamin D absorption, and is the vitamin D3 present in the feed biologically available.