Assessing blood serum copper levels in hair sheep grazing alfalfa pasture California State Polytechnic University, Pomona Vivian Ngo, Veronica Edwards, and Heather Nevins Mentor: Dr. Allen Pettey

Copper

Introduction Copper toxicity Acute: occurs after eating a large amount of copper in a feedAcute: occurs after eating a large amount of copper in a feed Chronic: occurs after ingesting larger amounts of copper in the diet over a period of time.Chronic: occurs after ingesting larger amounts of copper in the diet over a period of time. Severe tissue damageSevere tissue damage DeathDeath

Introduction Copper in sheep Sheep highly susceptibleSheep highly susceptible Bound in the liver and builds upBound in the liver and builds up Stress causes copper stores to be released into the blood streamStress causes copper stores to be released into the blood stream

Study Objective Assess the effects of stress on sheepAssess the effects of stress on sheep Use a copper assay kit to measure serum copper in sheep before and after mineral supplementation.Use a copper assay kit to measure serum copper in sheep before and after mineral supplementation.

Materials and Methods Study Design:  Study took place March 3 rd - April 7 th 2014  25 Hair sheep (Dorper- Katahdin cross breed)  Stressor: hoof trimming position  All sheep were stressed for 2 minutes  Trace Mineral supplement

Materials and Methods 2 x 2 Factorial Design looking at the effects of: StressStress Mineral supplementationMineral supplementation Blood Collection Times  T1 [March 3] = (-) stress/ (-) supplement  T2 [March 5]= (+) stress/ (-) supplement  T3 [April 4]= (-) stress/ (+) supplement  T4 [April 7]= (+) stress/ (+) supplement

Materials and Methods Blood Processing:  Blood was centrifuged for 5 minutes at 1500 rpm  Serum was extracted and transferred to cryo vial tubes  Samples were stored at -70ºC until ready to run copper assay  Assay Kit used: QuantiChromTM Copper Assay Kit (DICU-250)  Spectrophotometer was used to quantify the Cu concentration

Results  Main Effect of Stress – (P<0.12)  Main Effect of Supplementation – (P<0.14)  Interaction – (P<0.01)  Normal Copper levels are 1-2 ppm Values in PPM Stress - Stress+Avg Supp Supp Avg

Discussion Why did stress have different effects with and without supplementation?  Sheep may have been stressed by an even bigger stressor, which made our stressor not as effective  The temperature for the first and second collection times was:  Feb. 28, 55˚F high - storm  March 1, 59˚F high - storm  March 2, 55˚F high - cloudy  March 3, 66˚F high - collection T1  March 5, 71˚F high - collection T2  The temperature for the other collection times were:  April 5, 81˚F high - collection T3  April 6, 80˚F high  April 7, 92˚F high - collection T4

Conclusion  Measurable differences in serum copper can be detected in hair sheep  Weather events may have had an effect on our serum copper levels  Further investigation into copper levels during stressful events is needed

Questions?