The Florida Bull Test 2011-201212 March 2013
Results of an evaluation test are discussed that rated Hereford, Brahman, Angus, Simmental, SimAngus and Braford bulls on feed efficiency.
The 2011-2012 Florida Bull Test consisted of a 112-day performance test and a breeding soundness evaluation of each bull that qualified for the auction. Upon arrival, bulls were sorted into contemporary groups based on consignor and breed (8–12 bulls per pen) and housed in the University of Florida North Florida Research and Education Center (NFREC) Feed Efficiency Facility where they received free-choice access to feed and water with a target to gain 3.5 lb/day.
The diet consisted of 42 per cent pelleted soy hulls, 41 per cent pelleted corn gluten meal, 12 per cent loose peanut hulls, and 5 per cent molasses liquid supplement containing vitamins, minerals, and ionophore (monensin) on a dry matter (DM) basis. The diet was formulated to contain 16.3 per cent crude protein (CP) and 0.51 Mcal net energy of gain (NEg) per lb of diet DM.
After a three-week adaptation period, bulls were weighed on two consecutive days to obtain an objective average unshrunk starting weight, which became the on-test starting weight. Bulls were inspected daily for any arising health problems.
An intermediate unshrunk weight was obtained 28 days after starting the test, followed by unshrunk weights on two consecutive days to obtain an accurate 56-day weight and complete the feed efficiency portion of the test.
On day 56 of the test, bulls were moved from the Feed Efficiency Facility onto 3.25 acre pastures where they stayed for the remainder of the test. On the pasture, bulls remained in the same groups that were assigned in the pens in the Feed Efficiency Facility.
Bulls also continued receiving free-choice access to the same diet they were fed in the Feed Efficiency Facility, with the addition of free-choice bermudagrass hay. An additional intermediate weight was assessed on day 84 of the test, followed by the conclusion of the 112-day feeding period, when bulls were weighed again on two consecutive days to determine the final test weight.
Animal performance, specifically average daily gain (ADG), was calculated using only the official starting and finishing test weights. Throughout the test, bulls were observed and screened for structural soundness and disposition. Bulls deemed structurally unsound or those having poor disposition did not qualify for the sale.
Assessment of Feed Efficiency
After bulls arrived at the Feed Efficiency Facility, they were fitted with electronic identification (EID) tags to monitor daily feed intake using the GrowSafe system, and ADG was calculated for the 56-day feed efficiency portion of the test. Residual feed intake (RFI) was the measure of feed efficiency used to rank the bulls in the bull test, and it was calculated as the difference between actual feed intake and expected feed intake. Daily feed intake was measured on each individual bull, and RFI was calculated (described previously by Maddock and Lamb 2009, available at http://edis.ifas.ufl.edu/an217).
The Florida Bull Test focuses on testing bulls on a diet that includes a grain-based supplement and ad libitum access to forage. Overall ranking for the test is based on ADG and the weight per day of age (WDA), generating an index ratio.
The top performing bull and top performing Angus bull in the test was R & A Bold Image 817 owned by R & A Angus of Mebane, NC, which indexed 135 with an ADG of 5.23 lb/day and WDA of 3.24 lb/day. The top SimAngus bull in the test, J&W Mr. Powder River owned by J & W Simmentals from Headland, AL, was ranked second overall and indexed 125 with an ADG of 3.97 lb/day and WDA of 3.87 lb/day.
The top Simmental bull, J & W Heartbreaker, was also owned by J & W Simmentals, ranked third overall, and indexed 122 with an ADG of 4.00 lb/day and WDA of 3.68 lb/day. The top Brahman bull, FF Mr. Ruben Duno Manso 103 owned by Ford Farms from Malone, FL, was ranked 42 overall and indexed 90 with an ADG of 2.96 lb/day and WDA of 2.69 lb/day. The top Hereford bull, JTN Anhinga K16 R08 X15 owned by Taylor Neighbors from Americus, GA, was ranked 45 overall and indexed 91 with an ADG of 2.73 lb/day and WDA of 2.98 lb/day. Feed efficiency data is summarized in Table 1.
|Table 1. Summary of Feed Efficiency Data for Bulls in the 2011-2012 Florida Bull Test|
|Item||Daily Intake, lb/day||RFI, kg/day||Feed:Gain|
|Range||17.27 – 32.46||-3.03 – 2.36||5.48 – 16.18|
The Florida Bull Test Sale was held on January 14, 2012. Of the 63 bulls tested, 57 qualified for the sale, but only 45 were on offer at the NFREC in Marianna, FL. The sale grossed $127,550 with an average of $2,834 per lot. Angus bulls averaged $2,525 on 26 lots; Hereford bulls averaged $2,850 on 2 lots; SimAngus bulls averaged $3,338 on 8 lots; and Simmental bulls averaged $3,278 on 9 lots. The highest selling bull was lot 3, J&W Heartbreaker, selling for $4,750. He was purchased by Southern Cattle Company of Marianna, FL. The consignor was J&W Simmentals of Headland, AL.
Maddock, T.D., and G. C. Lamb. 2009. The Economic Impact of Feed Efficiency in Beef Cattle. AN217. Gainesville: University of Florida Institute of Food and Agricultural Sciences. http://edis.ifas.ufl.edu/an217.