Onset and severity of osteoporosis may be delayed or lessened if bone metabolism and peak bone mass in the young is optimized through nutrition. The study objective is to determine whether different sources of omega‐3 fatty acids in the diet induce changes on bone. Young (28 day) female Sprague‐Dawley rats were randomly assigned n=10/group to a high 12% (weight) fat diet consisting of either corn oil (CO) or the omega‐3 fatty acid rich krill (KO), flaxseed (FO) or menhaden (MO). After 8‐weeks, rats were euthanized and femur and tibia were collected. Bone morphometry was measured using calipers. Serum alkaline phosphatase (ALP), calcium (Ca), and phosphorous (P) were determined by calorimetric enzymatic assay. Bone mineral content (BMC) was determined by ashing at 600°C. Bone strength was measured using a 3‐point bending test. There were no differences in bone morphometry, except rats fed KO had shorter (P=0.02) tibia length compared to rats fed MO. There were no significant differences in serum ALP, Ca or P among the treatment groups. BMC was higher (P<0.001) in rats fed MO and FO compared to CO. There was no significant difference in bone strength indicated by in peak force among the treatment groups. Based on the results, different sources of omega‐3 fatty acids may influence bone health.

Renal tissue is influenced by dietary composition in rodents. Evidence suggests that renal diseases may be modulated by dietary polyunsaturated fatty acids (PUFAs). Therefore, the objective of our study was to evaluate kidney function in rats fed diets differing in PUFAs. Young (28 d) female Sprague‐Dawley rats (n=10/group) were individually housed in metabolic cages to collect urine. Rats were pair‐fed high fat diets (12% by weight) consisting of corn oil (CO) rich in n‐6 PUFAs, or flax (FO), menhaden (MO), or krill (KO) oils rich in n‐3 PUFA. After 8 weeks rats were euthanized and serum and both kidneys were collected. Kidney function was assessed by measuring serum total protein, albumin, blood urea nitrogen (BUN), creatinine, calcium (Ca), and phosphorus (P) by colorimetric reactions. Urinary protein was determined by colorimetric assay. Kidney tissue and urinary mineral content was determined by inductively‐coupled plasma spectrometry. Rats fed KO had heavier (P<0.01) kidney weights than rats fed FO or MO. No differences were found in serum measurements of kidney function. However, urinary protein was higher (P=0.03) in rats fed KO compared to rats fed MO. Rats fed KO also had the highest (P<0.001) urinary P content. The data suggests that different dietary PUFAs influence urinary protein and mineral content, conditions associated with the development of kidney diseases. Funding NRI Grant #1004489R USDA‐NIFA.

Omega‐3 polyunsaturated fatty acid (n‐3 PUFA) sources providing high bioavailability and tissue accretion with the least peroxidation favor maximal health benefits. The study objective was to determine the tissue accretion and stability of n‐3 PUFAs from different sources. Young (28 d) female Sprague‐Dawley rats (n=10/group) were pair‐fed high fat (12% lipid/wt) diets containing either corn oil (CO) or n‐3 PUFA rich oils derived from flaxseed (FO), krill (KO), or menhaden (MO). Rats were individually housed in metabolic cages to determine apparent lipid digestibility: [(lipid intake – fecal lipid)/(lipid intake)] x 100. After 8 wks, liver and brain tissue were collected. Tissue fatty acid content (FA) was determined by gas chromatography and lipid oxidation by enzyme immunoassay for Thiobarbituric Acid Reactive Substances (TBARS). Lipid digestibility was lowest (p<0.05) in KO fed rats. In the brain, docosahexaenoic acid (DHA) was highest (p<0.02) in rats fed KO. In the liver, alpha‐linolenic acid was highest (p<0.001) in rats fed FO; eicosapentaenoic acid was higher (p<0.001) in rats fed KO, MO, and FO compared to CO. DHA was highest (p<0.001) in rats fed KO and MO. TBARs were similar among diet groups. Different sources of n‐3 PUFAs had different effects. Despite low digestibility, KO increased tissue DHA content without increasing tissue oxidation. Funding NRI #1004489 USDA NIFA grant.