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

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

Why Feed Efficiency? l Feed cost represents 60% of the total cost in finishing cattle BIF) l Feed cost represents 63% of total financial cost to run a beef cow. (Strohbehn, IA SPA results ) 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)

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)

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

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.

I remember when… ’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

<-PinPointer 4000 system Technology Advancements

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

GrowSafe System, Canada

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.

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:

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.

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

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

Warden’s Adjusted Feed Conversion

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

Warden’s Adjusted Feed Conversion bull New Level bull 0350 bull 4 Point 8 bull Warden Smarts SireAdj Feed Conversion New Level Point bull 4333 bull

Warden’s Adjusted Feed Conversion bull New Level bull 0350 bull 4 Point 8 bull Warden Smarts SireRFI New Level Point bull 4333 bull

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

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%

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

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

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

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

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

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

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.

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

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