By Dr. Steve Sachtleben, Kent Beef Nutritionist
Both field trials and research data from the Kent Nutrition Group (KNG) Product Development Center have shown that stressed calves benefit when fed KNG’s BoVantage®. Intakes are stimulated and average daily gains enhanced, while morbidity and mortality decrease. Next, we looked at the response of growing and finishing cattle to this natural nutritional package.
In the initial study, data were examined to determine the effect of BoVantage® on overall feedlot performance. Cattle fed BoVantage® from Day 1 of the grower phase until slaughter were observed to gain faster due to stimulated dry matter intake. Cattle fed BoVantage® throughout the trial (157 days on feed) were 25.12 lb heavier at slaughter than control, non-BoVantage® steers.
Factoring in the additional feed consumption over the study, plus the cost of BoVantage®, return on investment was still about $9.25/head (fat cattle price $1.05/cwt). Unfortunately, when fed cattle prices declined (mid -$80/cwt), this scenario turned unprofitable. However, it turns out 85-90% of the cattle’s response to BoVantage® occurred the last 28 days before harvest. This suggested that feeding BoVantage® only the last 28 days of the feeding period could translate into savings while maintaining most of the feedlot performance.
As KNG research into this late growth period for BoVantage® was being planned, an FDA-approved growth promotant, Optaflexx® (ractopamine HCL), looked like it might be a good fit to feed concurrently with BoVantage®. Optaflexx® has a four-to-six week pre-harvest feeding recommendation and has a claim for enhanced rate of gain, improved feed efficiency, and increased carcass leanness.
All cattle from the above trial (Sachtleben, 2010) received the same base diet of shelled corn, dried distillers grains with soluble (DDGS), KNG Co-Product Balancer 667R and limited corn silage. KNG’s BoVantage® product and Optaflexx® via KNG’s Cattleflex® 1600 were included as indicated. All steers were implanted.
|Treatment||Description||ADG, lb||DMI, lb||F/G|
|1||Control – No Additive||3.38d||22.11abc||6.55a|
|2||Optaflexx – Last 28 days||3.94b||21.79abc||5.50a|
|3||BoVantage – 28 days*||3.63c||22.96a||6.34a|
|4||BoVantage – 28 Days + Optaflexx**||4.18a||22.87ab||5.51b|
|*BoVantage last 28 days only.|
|**BoVantage w/Optaflexx (200 mg/hd/day) for 28 days.|
|abcdLSD (P < .15)|
Control cattle gained slower than all other treatment groups. The addition of BoVantage stimulated (P < .15) ADG, as did Optaflexx®. BoVantage®, plus Optaflexx®, supported the best rate of gain. These dual additions resulted in an associative response. All dry matter intake (DMI) data from test cattle were similar to control steers. Trends in this trial (P > .05) again suggest that BoVantage® stimulates DMI and does not generally improve feed efficiency.
Carcass data were collected on individual steers and while large variability within treatment groups made statistical differences difficult to detect, strong trends were apparent. Steers fed BoVantage® plus Optaflexx® tended to have less internal fat and higher hot carcass weights than other treatment groups.
From the above performance data, the following 28-day economic summary was developed.
|Treatment||Description||Wt Value*||Additive Cost||F/G Improvement*||$ Return vs. Control|
|*Corn at $5.00/bushel, cattle fat price at $1.25/lb and additive costs are suggested retail.|