Merial

The historical evidence against implants as a major contributing factor to the buller steer syndrome is confounded by the fact that during the same time in which the feedlots were being monitored and an increase in buller incidence was observed, the number of cattle on feed nearly doubled. This lead to an increase in the number of animals per pen, and at the same time the dosage of anabolic agents fed or implanted to cattle increased substantially.

The historical evidence against implants as a major contributing factor to the buller steer syndrome is confounded by the fact that during the same time in which the feedlots were being monitored and an increase in buller incidence was observed, the number of cattle on feed nearly doubled. This lead to an increase in the number of animals per pen, and at the same time the dosage of anabolic agents fed or implanted to cattle increased substantially.

Although the use of growth promoting implants plays a role in the buller steer syndrome, implants are not entirely responsible for its occurrence, as bullers are observed even in feedlots where implants are not used (Irwin et al., 1979; Ulbrich, 1981).

Although the use of growth promoting implants plays a role in the buller steer syndrome, implants are not entirely responsible for its occurrence, as bullers are observed even in feedlots where implants are not used (Irwin et al., 1979; Ulbrich, 1981).

Also, although greater dosages of estrogenic implants may increase the possibility of bullers, greater dosages of implants also result in greater performance; reducing the implant dosage in order to reduce bulling in a small percentage of cattle may also result in lost performance and carcass weight of the entire pen resulting in reduced profitability.

Also, although greater dosages of estrogenic implants may increase the possibility of bullers, greater dosages of implants also result in greater performance; reducing the implant dosage in order to reduce bulling in a small percentage of cattle may also result in lost performance and carcass weight of the entire pen resulting in reduced profitability.

The mounting behavior exhibited by steers suffering from buller steer syndrome is often thought of as a sexual behavior, but typical sexual behaviors such as lip-curling, penile erections, and intromission are not exhibited by riders. Riding is therefore more likely a way for a steer to exert dominance over another steer.

The mounting behavior exhibited by steers suffering from buller steer syndrome is often thought of as a sexual behavior, but typical sexual behaviors such as lip-curling, penile erections, and intromission are not exhibited by riders. Riding is therefore more likely a way for a steer to exert dominance over another steer.

The mounting behavior seen among feedlot buller steers is more likely to be related to social behavior, since in wild species of ungulates which are in the same

The mounting behavior seen among feedlot buller steers is more likely to be related to social behavior, since in wild species of ungulates which are in the same taxonomic family as domestic beef cattle, submissive behavior is expressed by allowing the dominant animal to mount. taxonomic family as domestic beef cattle, submissive behavior is expressed by allowing the dominant animal to mount.

One observational study by Klem et al. (1983) found that bullers were actually more aggressive than riders and the authors postulated that bullers may not be readily submitting to dominant riders. Social hierarchies between cattle appear to play a role in the generation of bullers in a feedlot setting. Dominant steers are naturally more aggressive than other steers in the pen, so they like to establish their dominance. Not surprisingly, when steers first arrive at a feedlot and are penned together, the number of bullers is at its highest.

One observational study by Klem et al. (1983) found that bullers were actually more aggressive than riders and the authors postulated that bullers may not be readily submitting to dominant riders. Social hierarchies between cattle appear to play a role in the generation of bullers in a feedlot setting. Dominant steers are naturally more aggressive than other steers in the pen, so they like to establish their dominance. Not surprisingly, when steers first arrive at a feedlot and are penned together, the number of bullers is at its highest.

When animals are re-grouped, the number of bullers rises again as new pen members establish their social status. There is also evidence that suggests the expression of social dominance occurs more often in pens with large numbers of animals (Grognet, 2004; Brower and Kiracofe, 1978; Irwin et al., 1979).

When animals are re-grouped, the number of bullers rises again as new pen members establish their social status. There is also evidence that suggests the expression of social dominance occurs more often in pens with large numbers of animals (Grognet, 2004; Brower and Kiracofe, 1978; Irwin et al., 1979).

Hormonal blood levels have also been implied to be a factor that contributes to the occurrence of the buller steer syndrome in the feedlot industry. Epp at al. (2008) reported that bullers, compared to control steers, have suppressed serum concentrations of progesterone, increased estrogen and testosterone levels, and 74.5% greater levels of monoamine oxidase type A (monoamine neurotransmitter enzyme responsible for modifying behavior the same molecule associated with psychopathic behaviors in humans) mRNA activity.

Hormonal blood levels have also been implied to be a factor that contributes to the occurrence of the buller steer syndrome in the feedlot industry. Epp at al. (2008) reported that bullers, compared to control steers, have suppressed serum concentrations of progesterone, increased estrogen and testosterone levels, and 74.5% greater levels of monoamine oxidase type A (monoamine neurotransmitter enzyme responsible for modifying behavior---the same molecule associated with psychopathic behaviors in humans) mRNA activity.

Brower and Kiracofe (1974; 1978) reported an elevated blood estrogen level in buller steers vs. nonbuller steers. Similarly, Irwin et al. (1979) reported that higher levels of urinary estrogen and testosterone were detected in buller steers compared to their non-buller pen mates. It is possible, however, that the greater estrogen levels were not causative of buller activity, but instead are elevated due to the buller steer being ridden, since hormonal profiles returned to basal levels after 3 days of isolation.

Brower and Kiracofe (1974; 1978) reported an elevated blood estrogen level in buller steers vs. nonbuller steers. Similarly, Irwin et al. (1979) reported that higher levels of urinary estrogen and testosterone were detected in buller steers compared to their non -buller pen mates. It is possible, however, that the greater estrogen levels were not causative of buller activity, but instead are elevated due to the buller steer being ridden, since hormonal profiles returned to basal levels after 3 days of isolation.

How Much Do Bullers Cost?

How Much Do Bullers Cost?

Besides the animal welfare concern for buller steers, the extra handling necessary to accommodate these cattle, the disruption to the uniform marketing of cattle, particularly in custom feedlots (Taylor et al., 1997a), the need for extra pens in which to house bullers, and the losses due to injury, treatment and death add significantly to the cost of operating a feedlot.

Besides the animal welfare concern for buller steers, the extra handling necessary to accommodate these cattle, the disruption to the uniform marketing of cattle, particularly in custom feedlots (Taylor et al., 1997a), the need for extra pens in which to house bullers, and the losses due to injury, treatment and death add significantly to the cost of operating a feedlot.

An epidemiological investigation found that bullers were 2.5 times more likely to be reclassified as "sick" and 3.2 times more at risk to die than non -buller steers (Taylor et al., 1997b), suggesting additional costs of the buller steer syndrome for the feedlot. There is no question that the buller steer syndrome has a significant impact on animal welfare, animal health, and is an economic burden to feedlot operators (Grognet, 2004).

An epidemiological investigation found that bullers were 2.5 times more likely to be reclassified as “sick” and 3.2 times more at risk to die than non-buller steers (Taylor et al., 1997b), suggesting additional costs of the buller steer syndrome for the feedlot. There is no question that the buller steer syndrome has a significant impact on animal welfare, animal health, and is an economic burden to feedlot operators (Grognet, 2004).

The buller steer syndrome increases the propensity of reduced performance and health, injury, morbidity, and possibly mortality. A survey of nearly 2,000 necropsies performed at several Colorado feedlots showed that 3.8% cattle died from riding injuries, without considering the probable carcass losses of surviving bullers due to bruising and discoloration (Pierson et al., 1976).

The buller steer syndrome increases the propensity of reduced performance and health, injury, morbidity, and possibly mortality. A survey of nearly 2,000 necropsies performed at several Colorado feedlots showed that 3.8% cattle died from riding injuries, without considering the probable carcass losses of surviving bullers due to bruising and discoloration (Pierson et al., 1976).

In addition to the economic cost relative to animal performance, feedlot managers should also consider costs of extra labor, facilities, and carcass implications incurred with buller behavior. Ulbrich (1981) mentioned that the economic loss attributed to buller steers occurred not only from carcass bruising or animal death, but also there was a loss of the dead animal’s accumulative feed cost. Some of the factors most cited by feedlot managers and consultants as to why bullers account for extra billing charges for a feedlot are:

In addition to the economic cost relative to animal performance, feedlot managers should also consider costs of extra labor, facilities, and carcass implications incurred with buller behavior. Ulbrich (1981) mentioned that the economic loss attributed to buller steers occurred not only from carcass bruising or animal death, but also there was a loss of the dead animal’s accumulative feed cost. Some of the factors most cited by feedlot managers and consultants as to why bullers account for extra billing charges for a feedlot are:

• Losses due to injury or death

 Losses due to injury or death

• Reduced final weight of bullers and riders

 Reduced final weight of bullers and riders

• Bruising, leading to excessive carcass trim

 Bruising, leading to excessive carcass trim

• Labor required to segregate bullers

 Labor required to segregate bullers

• Complicated pen utilization

 Complicated pen utilization

• Increased paperwork and recordkeeping

 Increased paperwork and recordkeeping

No recent economic figures have been reported as to how much a buller steer will cost a feedlot. The estimated cost of a steer suffering from the buller steer syndrome to a feedlot was set at $23.68 USD per buller in 1972 based on economic losses experienced by Kansas feedlot operators (Brower and Kiracofe, 1978; Turgeon and Koers, 1997). According to Peck (2005),

No recent economic figures have been reported as to how much a buller steer will cost a feedlot. The estimated cost of a steer suffering from the buller steer syndrome to a feedlot was set at $23.68 USD per buller in 1972 based on economic losses experienced by Kansas feedlot operators (Brower and Kiracofe, 1978; Turgeon and Koers, 1997). According to Peck (2005), the economic impact of buller steers has been empirically estimated at $25 to $35 USD per buller steer due to several performance and management issues. the economic impact of buller steers has been empirically estimated at $25 to $35 USD per buller steer due to several performance and management issues.

Blackshaw et al. (1997) reported that in 1997 the buller steer syndrome cost for the feedlot industry was estimated at $70 USD per buller steer, representing a significant economic loss.

Blackshaw et al. (1997) reported that in 1997 the buller steer syndrome cost for the feedlot industry was estimated at $70 USD per buller steer, representing a significant economic loss.

To calculate the cost of a buller steer for the feedlot industry in 2015 we used the Consumer Price Index Inflation Calculator (Bureau of Labor Statistics). Adjusting the 1972 cost of $23.68 USD reported by Brower and Kiracofe (1978), after accounting for inflation, to 2015 the cost of a buller steer for the feedlot industry would be of $134.04 USD per buller.

To calculate the cost of a buller steer for the feedlot industry in 2015 we used the Consumer Price Index Inflation Calculator (Bureau of Labor Statistics). Adjusting the 1972 cost of $23.68 USD reported by Brower and Kiracofe (1978), after accounting for inflation, to 2015 the cost of a buller steer for the feedlot industry would be of $134.04 USD per buller.

So, in order to put the economic impact of the buller steer syndrome into perspective let’s do some math. According to the Beef Industry Statistics report (NCBA) for 2014 the total U.S. commercial slaughter of beef cattle was 31,950,000 head, from which 15,378,200 were steers (USDA, 2015).

So, in order to put the economic impact of the buller steer syndrome into perspective let’s do some math. According to the Beef Industry Statistics report (NCBA) for 2014 the total U.S. commercial slaughter of beef cattle was 31,950,000 head, from which 15,378,200 were steers (USDA, 2015).

The buller incidence in the U.S. feedlot industry is reported as 2.45%, which means that in average, during 2014, 376,766 head of cattle were bullers. At a cost of $134.11 USD per buller, calculated for 2014, the estimated cost of bullers for the beef industry in 2014 was of $50,528,088 USD.

The buller incidence in the U.S. feedlot industry is reported as 2.45%, which means that in average, during 2014, 376,766 head of cattle were bullers. At a cost of $134.11 USD per buller, calculated for 2014, the estimated cost of bullers for the beef industry in 2014 was of $50,528,088 USD.

Management and Treatment

Management and Treatment

There does not seem to be an easy management strategy or treatment to prevent the buller steer syndrome, which we have calculated causes a significant economic loss for the beef industry sexual behavior? Large Anim. Vet. 50:6. sexual behavior? Large Anim. Vet. 50:6.

There does not seem to be an easy management strategy or treatment to prevent the buller steer syndrome, which we have calculated causes a significant economic loss for the beef industry.

Besides common management practices (feeding routines, proper animal handling, stress reducing techniques) there are very few suggestions available in the literature of how to prevent the buller steer syndrome from happening. Turgeon et al. (1997) reported that in pens containing an average of 318 animals had roughly double the incidence of bullers vs. pens averaging 178 head.

Besides common management practices (feeding routines, proper animal handling, stress reducing techniques) there are very few suggestions available in the literature of how to prevent the buller steer syndrome from happening. Turgeon et al. (1997) reported that in pens containing an average of 318 animals had roughly double the incidence of bullers vs. pens averaging 178 head.

Blackshaw et al. (1997) suggested that the two important management factors associated with the buller steer syndrome that are usually not taken into account are group/pen size and season. These authors recommended that population of pens should be kept below 250 head and that feedlots should pay close attention to cattle management before and during warm weather season as stressful circumstances during this time of the year are reported to increase the incidence of buller activity. Many methods for mitigating the buller steer syndrome are related to good animal husbandry practices (McDaniel and Holt, 2013).

Blackshaw et al. (1997) suggested that the two important management factors associated with the buller steer syndrome that are usually not taken into account are group/pen size and season. These authors recommended that population of pens should be kept below 250 head and that feedlots should pay close attention to cattle management before and during warm weather season as stressful circumstances during this time of the year are reported to increase the incidence of buller activity. Many methods for mitigating the buller steer syndrome are related to good animal husbandry practices (McDaniel and Holt, 2013).

Proper management of buller cases requires prompt removal of the affected buller steer to a separate hospital or sick pen in isolation, with other bullers, or to a pen of heifers (Brower and Kiracofe, 1972; Sprague, 1999) where buller activity usually disappears.

Proper management of buller cases requires prompt removal of the affected buller steer to a separate hospital or sick pen in isolation, with other bullers, or to a pen of heifers (Brower and Kiracofe, 1972; Sprague, 1999) where buller activity usually disappears.

Moseley et al. (2003) reported that steers observed to be bullers were pulled from their pens, allowed a 3 to 7 day stay in a hospital pen (to decrease bulling activity), and then returned to their home pens. If large numbers of bullers are combined in a single recovery pen, the bullers may themselves begin riding other steers. Therefore, it has been recommended to limit the number of bullers within a single recovery pen.

Moseley et al. (2003) reported that steers observed to be bullers were pulled from their pens, allowed a 3 to 7 day stay in a hospital pen (to decrease bulling activity), and then returned to their home pens. If large numbers of bullers are combined in a single recovery pen, the bullers may themselves begin riding other steers. Therefore, it has been recommended to limit the number of bullers within a single recovery pen.

Moseley et al. (2003) reported that steers observed to be bullers were pulled from their pens, allowed a 3 to 7 day stay in a hospital pen (to decrease bulling activity), and then returned to their home pens. If large numbers of bullers are combined in a single recovery pen, the bullers may themselves begin riding other steers. Therefore, it has been recommended to limit the number of bullers within a single recovery pen. Several feedlot operators recommend limiting the number to less than 50 bullers per hospital pen to avoid bulling within the hospital pens.

Epp, M.P., D.A. Blasi, B.J. Johnson, J.P. Kayser, D.M. Grieger, J.S. Stevenson, and J.E. Minton. 2008 Serum steroid concentrations at differente phases of production and brain monoamine oxidase type a messenger ribonucleic acid in buller steers. The Professional Animal Scientist 24(2008):552-559.

Epp, M.P., D.A. Blasi, B.J. Johnson, J.P. Kayser, D.M. Grieger, J.S. Stevenson, and J.E. Minton. 2008 Serum steroid concentrations at differente phases of production and brain monoamine oxidase type a messenger ribonucleic acid in buller steers. The Professional Animal Scientist 24(2008):552-559.

Grognet, J. 2004. Buller steers a costly problem – Animal Health. The Western Producer. http://www.producer.com/2004/11/buller -steers-a-costly-problem-animal-health/

Grognet, J. 2004. Buller steers a costly problem – Animal Health. The Western Producer. http://www.producer.com/2004/11/buller -steers-a-costly-problem-animal-health/

Several feedlot operators recommend limiting the number to less than 50 bullers per hospital pen to avoid bulling within the hospital pens. Once the buller has rested and recovered, it can be returned to its home pen (Grognet, 2004) where it should be closely monitored as one in every three buller steers will exhibit buller behavior again (Stookey, 1997).

Once the buller has rested and recovered, it can be returned to its home pen (Grognet, 2004) where it should be closely monitored as one in every three buller steers will exhibit buller behavior again (Stookey, 1997).

Conclusion

Several feedlot operators recommend limiting the number to less than 50 bullers per hospital pen to avoid bulling within the hospital pens. Once the buller has rested and recovered, it can be returned to its home pen (Grognet, 2004) where it should be closely monitored as one in every three buller steers will exhibit buller behavior again (Stookey, 1997).

Irwin, M. R., D. R. Melendy, M. S. Amose and D. P. Hutcheson. 1979. The roles of predisposing factors and gonadal hormone levels in the buller syndrome of feedlot steers. J. Amer. Vet. Med. 174:367.

Irwin, M. R., D. R. Melendy, M. S. Amose and D. P. Hutcheson. 1979. The roles of predisposing factors and gonadal hormone levels in the buller syndrome of feedlot steers. J. Amer. Vet. Med. 174:367.

Klem, W. R., C. J. Sherry, L. M. Schake and R. F. Sis. 1983. Homosexual behaviour in feedlot steers: An aggression hypothesis. Appl. Anim. Ethol. 11:187 -195.

Klem, W. R., C. J. Sherry, L. M. Schake and R. F. Sis. 1983. Homosexual behaviour in feedlot steers: An aggression hypothesis. Appl. Anim. Ethol. 11:187 -195.

McDaniel, R. and S. Holt. 2013. Technical Review: Buller Steer Syndrome. Nutrition Service Associates. Queensland, Australia. http://www.feedlotsnsa.com.au/tweb/uplfiles/ NSA_Buller_Tech_Review.pdf

Conclusion

The buller steer syndrome has been a common problem seen in feedlot operations for over 50 years. Intangible monetary losses, as they haven’t been precisely quantified and reported recently, are estimated at about $134.04 USD per buller steer in 2015.

The buller steer syndrome has been a common problem seen in feedlot operations for over 50 years. Intangible monetary losses, as they haven’t been precisely quantified and reported recently, are estimated at about $134.04 USD per buller steer in 2015.

Conclusion

The buller steer syndrome has been a common problem seen in feedlot operations for over 50 years. Intangible monetary losses, as they haven’t been precisely quantified and reported recently, are estimated at about $134.04 USD per buller steer in 2015.

If not appropriately managed and monitored, buller steers will most likely have a decreased performance and are susceptible to injuries which leads to higher morbidity and mortality rates, carcass bruising which results in discounts at the packing plant, and additional management and labor costs at the feedlot.

If not appropriately managed and monitored, buller steers will most likely have a decreased performance and are susceptible to injuries which leads to higher morbidity and mortality rates, carcass bruising which results in discounts at the packing plant, and additional management and labor costs at the feedlot.

If not appropriately managed and monitored, buller steers will most likely have a decreased performance and are susceptible to injuries which leads to higher morbidity and mortality rates, carcass bruising which results in discounts at the packing plant, and additional management and labor costs at the feedlot.

When a buller steer is detected in the pen, it should be removed from the pen, checked for health status, and housed in a separate pen for a short period of time, and returned to its home pen where it should continue to be monitored.

When a buller steer is detected in the pen, it should be removed from the pen, checked for health status, and housed in a separate pen for a short period of time, and returned to its home pen where it should continue to be monitored.

When a buller steer is detected in the pen, it should be removed from the pen, checked for health status, and housed in a separate pen for a short period of time, and returned to its home pen where it should continue to be monitored.

McDaniel, R. and S. Holt. 2013. Technical Review: Buller Steer Syndrome. Nutrition Service Associates. Queensland, Australia. http://www.feedlotsnsa.com.au/tweb/uplfiles/ NSA_Buller_Tech_Review.pdf

Moseley, W.M., D.M. Meeuwse, J.F. Boucher, K.J. Dame, and J.W. Lauderdale. 2003. A dose-response study of melengestrol acetate on feedlot performance and carcass characteristics of beef steers. J. Anim. Sci. 2003. 81:2699-2703.

Moseley, W.M., D.M. Meeuwse, J.F. Boucher, K.J. Dame, and J.W. Lauderdale. 2003. A dose-response study of melengestrol acetate on feedlot performance and carcass characteristics of beef steers. J. Anim. Sci. 2003. 81:2699-2703.

National Cattlemen’s Beef Association. Beef Industry Statistics report. 2014. http://www.beefusa.org/beefindustrystatistics.aspx

National Cattlemen’s Beef Association. Beef Industry Statistics report. 2014. http://www.beefusa.org/beefindustrystatistics.aspx

Peck, C. 2005. Got Bullers?. Beef Magazine http:// beefmagazine.com/mag/beef_bullers

Peck, C. 2005. Got Bullers?. Beef Magazine http:// beefmagazine.com/mag/beef_bullers

Pierson, R.E., Jensen, R., Braddy, P.M., Horton, D.P., and Christie, R.M. 1976. Bulling among yearling feedlot steers. J. Am. Vet. Med. Assoc. 169: 521-523.

Pierson, R.E., Jensen, R., Braddy, P.M., Horton, D.P., and Christie, R.M. 1976. Bulling among yearling feedlot steers. J. Am. Vet. Med. Assoc. 169: 521-523.

Prouty, F. and E. Larson. 2010. Comparison of reimplantation strategies using Synovex Choice and Synovex Plus with Revalor -XS in feedlot steers. The Professional Animal Scientist 26 (2010):76-81.

Prouty, F. and E. Larson. 2010. Comparison of reimplantation strategies using Synovex Choice and Synovex Plus with Revalor -XS in feedlot steers. The Professional Animal Scientist 26 (2010):76-81.

Sprague, J.I. 1999. Managing Buller Steers. Feedlot Magazine. http:// feedlotmagazine.com/archive/archive/issues/199909/ buller_pg32.html

Sprague, J.I. 1999. Managing Buller Steers. Feedlot Magazine. http:// feedlotmagazine.com/archive/archive/issues/199909/ buller_pg32.html

The key to mitigation, prevention, and management of bullers in the feedlot relates to good animal husbandry, humane treatment of cattle, animal welfare assurance, and best management practices put in place at the feedlot.**

The key to mitigation, prevention, and management of bullers in the feedlot relates to good animal husbandry, humane treatment of cattle, animal welfare assurance, and best management practices put in place at the feedlot.**

The key to mitigation, prevention, and management of bullers in the feedlot relates to good animal husbandry, humane treatment of cattle, animal welfare assurance, and best management practices put in place at the feedlot.**

Stookey, J.M. 1997. Buller Steer Syndrome. Alberta Feedlot Management Guide. http://www.usask.ca/wcvm/herdmed/ applied-ethology/articles/bullers.html

Stookey, J.M. 1997. Buller Steer Syndrome. Alberta Feedlot Management Guide. http://www.usask.ca/wcvm/herdmed/ applied-ethology/articles/bullers.html

Taylor, L. F., C. W. Booker, G. K. Jim, and P.T. Guichon. 1997a. Epidemiology investigation of the buller steer syndrome (riding behaviour) in a western Canadian feedlot. Aust. Vet. J. 75:45.

Taylor, L. F., C. W. Booker, G. K. Jim, and P.T. Guichon. 1997a. Epidemiology investigation of the buller steer syndrome (riding behaviour) in a western Canadian feedlot. Aust. Vet. J. 75:45.

Taylor, L.F., C.W. Brooker, G.K. Jim, and P.T. Guichon. 1997b. Sickness, mortality, and the buller steer syndrome in a western Canadian feedlot. Aus. Vet. J. 1997; 75:732-736.

References

References

Taylor, L.F., C.W. Brooker, G.K. Jim, and P.T. Guichon. 1997b. Sickness, mortality, and the buller steer syndrome in a western Canadian feedlot. Aus. Vet. J. 1997; 75:732-736.

References

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Blackshaw, J.K., A.W. Blackshaw, and J.J. McGlone. 1997. Buller steer syndrome review. Applied Animal Behaviour Science 54 (1997) 97-108.

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Voyles, B.L., M.S. Brown, R.S. Swingle, and K.J. Karr. 2004. Case Study: Effects of implant programs on buller incidence, feedlot performance, and carcass characteristics of yearling steers. The Professional Animal Scientist 20(2004):344-352.

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