1. Applying feed intake monitoring systems into producer testing programs Dr. Daryl R. Strohbehn Extension Beef Specialist Iowa Beef Center @ ISU

2. Why Feed Efficiency? l With everything else equal or even less wouldn’t you rather have a more feed efficient sire?

3. Why Feed Efficiency? l Feed cost represents 60% of the total cost in finishing cattle. (Fox @ 2002 BIF) l Feed cost represents 63% of total financial cost to run a beef cow. (Strohbehn, IA SPA results 2000- 04) l A 10% improvement in feed efficiency can improve feedlot profits 43%. (Fox, et.al. 2001) l 65-75% of total dietary energy cost in breeding cows is required for maintenance. (Ferrell & Jenkins 1985; NRC 1996) l A 5% improvement in feed efficiency has an economic impact 4 times greater than a 5% improvement in ADG. (Gibb & McAllister 1999)

4. Why Feed Efficiency? l Environmental friendly cattle l Selection for improved feed efficiency will: –Lower methane emissions by 9 to 12% (Okine, et.al. 2001) –Reduce manure N, P and K production by 15-17% (Arthur, et.al. 2002)

5. Why Feed Efficiency? It’s a heritable trait. TraitHeritability Feed conversion (f/g).36 Feed efficiency (g/f).42 Feed intake.41 Koots, et.al. 1994

6. Feed Conversion = Feed Intake / Animal Gain Example - 4:1 or 8:1 (lbs of dry matter / lb gain) Feed Efficiency = Animal Gain / Feed Intake Examples:.25 lbs gained / lb feed or.125 lbs gain / lb feed Efficiency Traits – Let’s get our definitions straight (usually expressed in units of 100% dry matter) Later on I will talk about RFI, NFI and NFE.

7. I remember when….1960-70’s l Individual fed bulls in separate pens –Example: Wye Plantation in Queenstown, Maryland l Daily hand kept written records l Very, very high labor l No animal peck order, thus no impact from competition

8. <-PinPointer 4000 system Technology Advancements

9. Calan Electronic Feed Gates  - Each animal has its own space and daily written records Technology Advancements System at Circle A Angus, MO

10. GrowSafe System, Canada

11. Feed Conversion testing with on the farm/ranch systems l Don’t take this job lightly –It’s like milking dairy cows, methodical daily duties. l Requires attention to feed and management details, regardless of intake monitoring system utilized. l Requires meticulous record keeping, both with feed intake and weight gains.

12. Record analysis assistance may be needed. l Feed conversion is just not feed intake divided by gain. l Most tests are equal time on feed, thus bull weights while on test vary a great deal. l BIF method: account for differences in average bull weights during test. Range in off test weight: 974 - 1541

13. BIF Methodology l Adjusted Feed Conversion uses metabolic weights. –( W.75 / W i.75 ) x ( Feed / Gain ) –W is the mid test weight; the average of the initial weight and final weight. –This method adjusts feed/gain of heavier than average bulls downward and lighter than average bulls upward.

14. Question ??? l Two bulls have the same Feed Conversion and 3.5 lb ADGs on 120 day test. –6.5 lbs feed to 1.0 lb gain –Bull A and B have off test weights of 1300 and 1200, respectively. –Are they the same for Feed Conversion? l NO ! –After adjusting for differences in body weight –Bull A’s average test weight was 1090 lbs, Bull B’s average test weight was 990 lbs »Bull A Adjusted FC=6.27 »Bull B Adjusted FC=6.74 Beef Improvement Federation Guidelines

15. Duane Warden Warden’s Ironwood Angus Council Bluffs, IA 24 years of feed efficiency testing using PinPointer system

16. Warden’s Adjusted Feed Conversion 1995-2004

17. 701 bull New Level bull 0350 bull 4 Point 8 bull 3303 bull 4333 bull Influence sires – Past and Present

18. Warden’s Adjusted Feed Conversion 1995-2004 701 bull New Level bull 0350 bull 4 Point 8 bull Warden Smarts SireAdj Feed Conversion 7015.84 New Level5.02 03505.18 4 Point 84.82 33035.21 43335.18 3303 bull 4333 bull

19. Warden’s Adjusted Feed Conversion 1995-2004 701 bull New Level bull 0350 bull 4 Point 8 bull Warden Smarts SireRFI 701-.70 New Level-2.20 0350-1.33 4 Point 8-2.61 3303-1.06 4333-2.50 3303 bull 4333 bull

20. Over 40 Years Ago l Dr. Robert Koch, U of Nebraska research and reported on a new system that adjusted feed intakes for body weight and growth. l Splits feed intake into two portions –1. feed intake for a given level of growth & size –2. a residual portion Data from: -Lincoln, NE -Fort Robinson, NE -Fort Reno, OK Breeds: Angus Hereford Shorthorn

21. Thus was born RFI (Residual Feed Intake) l RFI is also known as: –NFI: Net Feed Intake –NFE: Net Feed Efficiency l RFI is the difference between a bull’s actual feed intake and its expected feed intake based on its size and growth. l RFI = actual DMI – expected DMI l Heritability estimates 29% to 46%

22. RFI (Residual Feed Intake) l Used to identify animals that are either + or – from their expected ME intake. l -NFE = high efficiency l +NFE = low efficiency ADG Wt. Individual Bull Expected DMI Individual bull DMI -NFE

23. Studies indicate RFI is an independent trait l Warden data no correlation between Off Test Weight and RFI r = -.02

24. Studies indicate RFI is an independent trait l Warden data no correlation between ADG and RFI. r = -.01

25. Studies indicate RFI is an independent trait, but related to Adjusted Feed Conversion l Warden data.46 correlation between Adjusted Feed Conversion and RFI r =.46 RFI

26. Studies indicate RFI is an independent trait, but related to Dry Matter Intake l Warden data. 55 correlation between Dry Matter Intake and RFI. r =.55

27. Other relationships were evaluated…. l A significant correlation between RFI and ultrasound fat cover existed (.17) –Means fatter bulls were less efficient l No significant relationships existed between RFI and other performance parameters. –EPDs (BW, WW, YW, Milk) and ultrasound REA

28. Dilemma with calculating RFI l Requires doing a regression analysis of the data to develop an equation called Expected Dry Matter Intake. l Expected Dry Matter Intake is then used against Actual Dry Matter Intake to develop the RFI. l Not many producers have the expertise and knowledge of statistics to do this exercise. l Going to require serious expertise involvement either from Extension Service or Breed Association.

29. Warden-Beedle information gathering system using off the shelf electronic components. Joint project with the Iowa Beef Center, Miraco, ID-ology, and Rice Lake Scales

30. Our Future…..Let’s Hope. A view from Australia on the possibilities Angus NFI Percentile