Effects of Docility in Beef Cattle
It is not merely an inconvenience to deal with bad actors—there are some other good reasons to get rid of them.
Breeding Herd
A recent report from Florida (Cooke et al., 2009) investigated reproductive performance in pasture-mated cows based on a combined docility score. The scores were an average among those for reaction when in a chute, in a pen, and a measured exit velocity when released from the chute. Combined with plasma cortisol levels (a measure of animal stress), these workers found a negative relationship between the combined docility score and reproductive performance.
Several purebred cattle organizations have utilized a docility score (ranging from 1 to 6, with 1 indicating the most docile and 6 indicating the most aggressive) to predict docility in progeny by generating expected progeny differences for the trait. The heritability is moderate to high for docility (0.37 in the American Angus Association database), indicating that significant progress can be made in improving the trait through selective breeding for more docile cattle. Specific genes related to docility have been identified in cattle, and their presence can be determined in the laboratory by commercial companies that provide this service for this and many other traits.
Feedlot Cattle
Most of the data available on the influence of docility is related to feedlot cattle. Table 1 shows the results of docility on feedlot performance and carcass traits for over 13,000 cattle fed in southwestern Iowa during 2002-2004. These data clearly show docility can have a significant effect on the economics of feeding cattle.
| Item | Docile | Restless | Aggressive |
|---|---|---|---|
| % of total cattle | 72.4 | 21.8 | 5.8 |
| Overall ADG | 3.17 | 3.11 | 2.91 |
| Feed/Gain | 7.10 | 7.13 | 7.23 |
| Morbidity rate (%) | 19.2 | 16.8 | 16.2 |
| Mortality rate (%) | 1.09 | 1.02 | 1.91 |
| % prime | 1.7 | 1.2 | 0.1 |
| % choice | 72.4 | 67.9 | 58.1 |
| % select | 23.3 | 27.5 | 36.2 |
| % standard | 2.6 | 3.4 | 5.6 |
Busby, D., 2009.
At a choice/select spread of just $6.00/cwt, these results indicate that the value of docile cattle compared to aggressive cattle would be approximately $67.00 per steer. This does not include the additional feed, time in the feedlot, and increased treatment costs and death rate associated with aggressive cattle. Additionally, another study (Berg et al., 2009) indicated that cattle with a higher exit velocity after release from a chute had significantly higher toughness in their steaks, based on Warner-Bratzler shear values. A 1997 study in Colorado (Voisinet et al.) showed that the average daily gain of feedlot cattle was reduced by 0.4 lbs/day in English and continental breeds, and by 0.6 lbs/day in Brahman and Brahman-cross cattle, when temperament scores ranged from calm to continuous movement in a chute.
Culling Based on Docility
Most small-herd cattle managers are aware of the cattle with bad behavior in their herds. There is evidence that these cattle should be culled from the breeding herd because they will have both lower reproductive performance and a fairly high probability that their offspring will exhibit similar behavioral problems. Cattle feeders should critically evaluate docility in cattle at arrival and after 30 days in the feedlot. Studies show that some cattle that arrive at the feedlot under stress will overcome the behavioral problem after acclimation. However, if bad behavior persists, there are two major reasons to remove these cattle from the pen. First, their individual performance and carcass values will be reduced. Secondly, unpublished work at Penn State with small pens of cattle indicated that those cattle with poor behavior tended to influence bad behavior in their penmates as well. Cattle in pasture programs are more likely to exhibit increased behavioral problems due to fewer interactions with humans. Frustration in moving cattle and fixing fences will become a problem!
We always knew we didn't like dealing with bad actors. Here is the evidence to get rid of them and do yourself a favor in many ways.
Citations
- Berg, E. P., N. J. Hall, V. L. Anderson, B. R. Iisle, K. A. Carlin, and J. Galbreath. 2008. Working chute behavior of feedlot cattle can be an indication of cattle temperament and beef carcass composition and quality. North Dakota State University Department of Animal Science, Fargo.
- Busby, D. 2009. Disposition: convenience trait or economically important.
- Cooke, R. F., D. B. Araujo, G. C. Lamb, and J. D. Arthington. 2009. Effects of excitable temperament and its physiological consequences on reproductive performance of Brahman-crossbred cows. 2009 Beef Research Reports. Department of Animal Science, University of Florida, Gainesville.
- Voisinet, B. D., T. Grandin, J. D. Tatum, S. F. O'Connor, and J. J. Struthers. 1997. Feedlot cattle with calm temperaments have higher average daily gains than cattle with excitable temperaments. J. An. Sci. 75: 892-896.
Prepared by Dr. John Comerford, retired professor, Penn State
