Feed Efficiency in Cattle

⦁ Project Duration:  April 2015 - October 2016  18 months (extended from original grant at no cost)
⦁ Date of Report:  2/10/2017

 

 We run a 50-60 head beef cow herd in south central Iowa on approximately 100 acres. The entire farm is in grass pasture and woodlands, so winter feed must be purchased. Our herd has been primarily purebred Angus for over 20 years. Heifer replacements are retained, and the top bull calves sold as bulls. The remainder of the calf crop is usually sold in the winter months after weaning for at least 6 weeks.

We began rotational grazing starting over 15 years ago to increase the health of the pasture and the number of cows we can maintain. Although the paddocks are not as small as they could be, moving the herd every 2-3 days allows a stocking rate of 1 cow-calf per acre most years.

While raising cattle over the past 40 years, we have seen variations in cow size, changes in feed products and increased concern over the viability of beef cattle in general in an ever-shrinking world of resources and demand. Given that there are some acres in the country totally unsuited for cropping, our goal is to find the most economic and desirable combination of cattle phenotype and performance which is as sustainable as possible in all regards to further the benefits of raising beef cattle in the future. Therefore, we began testing for DNA growth, efficiency and quality genes when that technology became available in 2005. In 2011 we began using hard data feed efficiency testing as one of our primary selection traits and goals by enrolling weaning bulls into a test facility which had capability of testing for feed efficiency.

 

The request for this SARE grant was made to further refine what traits and "shortcuts" could be useful and as practical as possible in choosing herd sire and female replacement candidates. Since the primary advantage a beef animal has over other species or use of resources is their ability to utilize the "solar power" of photosynthesis and the growth of native grasses as a valuable resource, our grant application activity needed to include gain from grass grazing. The next phase of the grant proposal was feed efficiency testing done in a facility where intake and gain data is procured through the technology of feed bunk weighbars, RFID tags and computerized collection. The resulting compilation and summary of that data can be used to assist in choices. Additionally, there is now DNA testing available which is beginning to identify clusters of genes associated with various animal functions, including feed efficiency. Combining the newer DNA testing with the technology of testing for feed efficiency, and adding grass gain ability would give a more comprehensive comparison of what potential animals have as seedstock, and was therefore chosen as the steps for our grant proposal.

 

The grant was awarded to our family farm operation in the spring of 2015. The bulls selected for the project were weaned and then placed on fescue pasture. They then went to feed efficiency test, and had DNA testing completed that fall. All of the bulls in question were either used on our cows or sold and used as breeding bulls for others. We extended this final report as long as possible to ascertain if the bulls were successful for their intended purpose and were "trouble free" to the greatest extent possible.

 

We began rotational grazing to a limited degree approximately 15 years ago. Since starting, we have increased the number of paddocks to the point that we move cows between every 2-4 days depending on time of year and amount of precipitation. The lowest stocking rate so far has been a year when we only used .7 acres per cow/calf pair. Most years we are able to successfully use a 1 acre per pair stocking rate on "native" fescue pasture with red clover frostseeding every other year or so.

We had also started DNA testing for feed efficiency in 2006 and formal feed efficiency testing in 2011 for our weaning bull candidates.

GOALS

One of the goals of the project was to determine if there is currently any viable "short cut" in identifying efficient herd replacements and herd bulls without the added expense and time involved with doing the actual feed efficiency testing for each animal. It was taken as a given that feed efficiency heritability has been shown to be 40%, making it one of the higher heritable traits. It is also a fact that there has been no meaningful improvement in feedlot efficiency for several decades. 6:1 Feed:Gain conversion is still considered very good, with industry standard being 6.5-7:1. Both of these facts are reason why this goal was identified. 

 

Another goal of the project was to determine if grass gain for calves was correlated to feed efficiency testing or DNA testing. Identifying cows who will be efficient grazers has the greatest promise of increased sustainability -- more than even improving feedlot conversion. Cows eat daily for years and years, compared to a feedlot animal where feed efficiency savings lasts for less than one year. Reducing herd feed inputs and requirements saves both money for the producer, and environmental footprint elements for society and the environment. Reducing feed intake for mother cows by 15-20% would have a major impact on all levels of production.
 
During the course of the project, it was also found that there are many misconceptions and lack of understanding by the cow/calf producers in our area. Many believe that feed efficiency is only a concern for the feedlot and not their cow/calf operation. Another misconception is that high daily gain, or cattle who look fleshy are efficient. While these cattle may be, there are many who are not. Instead they are "big eaters" and look good as a result. Although not stated as a goal of this project initially, it seems as if the education of the people we have met and visited with through this project should also be listed as a goal at least partially achieved as this project ends.   

 

PROCESS
Phase 1):  Put newly weaned calves on all forage diet, and move them to first grass of the season ASAP. This was accomplished by weaning fall calves in early April and using an all-hay diet with supplemental barrels for balancing protein and providing a lick-source for mineral.

 

Calves were weighed at weaning, again when placed on grass three weeks later, and once again when taken off of grass 6 weeks after that. During the grass gain testing, the calves were given approximately 3 pounds of commodity-mix per day as a carrier for them to consume 4 oz. of yeast per day to aid in keeping their digestive system balanced during the changing weather and grass they were consuming. The importance of grass gain for calves comes from the fact that a cow's lactation decreases dramatically after the first 3-4 months. This then leaves it up to the ability of the calf to put on weight from additional input other than mother's milk. If a calf can gain well on grass at a young age, their weaning weight will increase without added supplemental feed for those producers who sell their calves at weaning.

 

Note: If a cow has an extended greater production lactation curve, say until 7 months when her calf is weaned, that cow would need a higher level of nutrition and feed cost than one who falls within the normal bell curve of milk lactation production. The cost of maintenance for the cow with increased lactation with the intent to increase weaning weight in that way alone would cost more than the calf gaining weight directly from their own forage intake. Feeding a cow in order to produce more weaning weight is an expensive/negative way to increase pay weight for calves.

 

Phase 2): Calves were placed at a test station facility where feed efficiency data could be collected. The calves spent approximately 2 weeks for a warm-up period, 70 days on feed efficiency test, and then 10 days to "normalize" back to the feed program for maintaining and slower growth than pushing for greater gains.

 

Phase 3): DNA samples were taken from each animal and put through a full 50K DNA test and also through a less intensive DNA test named GMX testing. The full blown DNA test cost was $75 each, while the GMX testing was only $17 each. Both tests were completed to once again see if there was a pattern which would allow a producer to use the least cost test and still have meaningful and useful results.

 

Phase 4): This was added on by the grantee as a follow-up on the bulls as they completed their first season of pasture work, and now some who have started siring calves.   
 

 

The grass gain testing of Phase 1 lasted 71 days total. 21 of the days small bales of hay were provided as the forage diet. The other 50 days the calves grazed on first growth on a 3 acre plot of fescue pasture. This pasture has been in sod for over 20 years.

 

Result #1: There were a total of 9 bull calves in this project. (The grant proposal had been budgeted for 8 calves) The calves were weighed at weaning and then when put on the first season growth pasture on 5/3/15. They were weighed again 33 days later when they were taken off of pasture and introduced to a commodity-mix grain ration to prepare them for feed efficiency testing.

The calves had excellent pasture gain. The individual gains were from 1.68#/day to 4.18#/day. They averaged 2.72#/day as a group. They were rotated through small paddocks laid out in a 3 acre fescue pasture. Their total weight gain on pasture was 858#. At the time of this project, 5-6 cwt calves were bringing $2.40 per pound at the local sale barn. At the time of this report, that weight calf is now selling for $1.45 per pound.
858 lbs x $2.40 (per pound price) = $2,059
858 lbs x $1.45 = $1,244

The value of the pasture the year of the test was $686 per acre ($2,059/3).
The value of the pasture at today's calf price of $1.40 is still $414 per acre - a very decent return on the ground use.

 

Result #2: The 9 bulls completed their feed efficiency test and the data from their RFID tags was evaluated through the Iowa State University connection with the feed testing facility. Average Daily Gain (ADG) for the group ranged from 3.03# to a high of 5.61#. Feed conversion range was 5.85#:1# gain to a low of 4.44#:1# gain.
Cost of Gain (COG) therefore ranged from .44 per pound to .58 per pound with feed costs of .10 per pound.
This results in a 600# gain difference of $82 in feed cost alone. There would also be added yardage costs for less efficient cattle in a commercial application.

 

The top 3 ADG bulls were also the top 3 in feed conversion in order of their ADG.
The 4th top ADG bull was the exception as he was 8th best in conversion.
The next 5 ADG bulls ranked then ranked 4, 5, 7 and 9th for conversion.

 

In relation to grass gain there was more variance:    
The top 2 ADG bulls (5.61# and 4.86#) were also the top 2 for grass gain (4.18# and 3.32#).
The 3rd top ADG bull (4.68#) was 4th in grass gain (2.71#).
The 4th top ADG bull (4.63#) was 9th (last) in grass gain (1.68#).
The only other exception to linking ADG and grass gain rankings was the 7th ADG bull (4.53#) who had the 3rd best grass gain (3.21#).

 

The result in comparing the "hard data" on these bulls does show a bias toward better gaining cattle doing better on conversion, as well as on grass gain. However, there are exceptions and this would be especially true in small group comparison of the individuals. It was also noted that the better performing bulls were out of older cows in the herd. This is likely attributed to the fact that older cows have a proven history of good production or they would not have been kept in the herd.

 

Result #3:  The DNA/GMX results and Angus Association EPD records were combined with the ADG and grass gain of all 9 bulls for the rankings as follows:

 

DNA         Act.     Grass   ADG   Residual            Frame      Actual            DNA         GMX             $B
calving      BW      Gain               Feed Intake        score        Feed              Docility    Ranking        from Angus
ease                                               (RFI)                              Conversion       Ranking    (100 best)      EPD

 6              6             1          1           4                       5             1                      3                 6                 9
 5              6             2          2           2                       5             2                      2                 8                 7
 9              8             4          3           1                       5             3                      8                 9                 8
 4              2             9          4           9                       3             8                      6                 2                 6
 8              4             6          5           5                       1             4                      7                 5                 2
 7              9             5          6           8                       2             5                      4                 2                 3
 3              3             3          7           7                       8             6                      1                 1                 5
 1              1             8          8           6                       4             7                      9                 7                 4
 2              2             7          9           3                       9             9                      5                 4                 1

 

Each line across is the record of an individual bull. They are placed in the chart according to ADG best to worse. It appears from this sample group that the $B EPD is not a good indicator for value of genetics for this group of bulls. This could be due to the fact that formulas for EPD's appear to have a bias to give newer genetics higher EPD values, and the bulls in this group are out of older cows. The duplicate numbers in the 1-9 scale occur in areas where there is a tie.

 

Result #4: We were able to visit with beef producers at 2 locations of the 2016 Iowa  Cattlemen's Annual convention last summer, the 2016 Iowa Grazing and Grass conference where a powerpoint presentation was given, and numerous meetings and conversations with producers over the last 18 months. Additionally, we have now visited with several of the current owners of the bulls who went through this project. The overall report is that they handled their first breeding season without losing condition. A few have started having calves already, and there are no problems being reported in calving difficulty.

DISCUSSION
At this point in time, it appears there is nothing better than actual testing of calves to determine which are most feed efficient in the feedlot and which gain best on pasture. The public contacts made about the process and purpose of this project appear to be well received and educational for many. Not being able to identify the better efficiency calves by body type was enlightening to many. The cost of feed efficiency testing large groups of animals is cost prohibitive.

 

By adding the criteria of having a good/excellent grass gain in addition to good ADG on feed test may come closest to choosing top replacement animals with lower cost involved than any other combination of the methods used in this project. The top combination of grass gain and feed gain identified the two top converting bulls in this project. Having an on-farm grass gain test and then feed test on the same farm is relatively easy and inexpensive if a person has access to a scale to determine daily gain. The animals were going to eat anyway, so the added cost is as much the time with weighing them than anything else. This is also much more economical than either trucking to a test facility and the costs of that testing or using DNA testing as added expenses.

 

The generational stacking of any trait is how "progress" toward breeding goals occurs. It certainly stands to reason that "stacking" the better combination grass and feed performers for a couple of generations will show improvement in overall herd efficiency. For our own Turtlerock herd, we are seeing significant savings (15-20%) in hay consumption for our cow herd with 2nd generation cows mated for feed efficiency now making up the majority of the herd. For the cow-calf producer willing to take the extra time and effort needed to do the two types of on-farm tests for grass and feed gain, the feed savings should quickly outdistance any added aggravation and time spent in measuring the gains. We would further suggest that when a person does not raise their own bulls, but does keep replacement heifers, a short grass gain test for females would sort out at least the bottom end in the group to cull, as the cow's primary function is converting grass to a usable form.  

As noted in several places in this report, there are significant economic gains in choosing for feed efficiency. This also impacts environmental impact since less feed is consumed (input) for the same or better results (output). Using less resources and still producing a quality consumer product would be a socially accepted goal by all except perhaps vegetarians.

 

The outcomes of generational selection for feed efficiency can reduce feed consumption for cow herds by a conservative 15% and for feedlot feed consumption by 30% or more (if feed lot conversion goes from 6.5:1 to 4:5:1 the reduction is 30.7%).

 

2016 powerpoint presentation on Grass Gain and Rotational grazing of young calves at the Iowa Forage and Grass Conference -  approximately 80 attendees. Several asked for and received copies of the powerpoint after the presentation.

 

 

2016 District Iowa Cattlemen Conventions held at Atlantic, IA and Riverside, IA. Turtlerock had a booth where we visited with attendees about grass gain testing, feed efficiency and rotational grazing. Approximately 100 attendees at each site.

 

2015 Ottumwa Cow-Calf Conference- Our display booth included SARE grant results and process. We were also interviewed on KIIC radio station concerning our SARE project while at this conference.

 

2016 and 2017 - further Ottumwa Cow-Calf conference display booth and conversations with attendees about the SARE project and the benefits we see in our herd.

 

Our Turtlerock Angus website has information about our feed conversion projects and how it can economically benefit a cow/calf producer.