Abstract

A receiving study was conducted to evaluate the effectiveness of a remote sensing ear tag on the detection of animal health, receiving calf performance, and finishing performance.

Crossbred steers (n= 628; initial BW = 270 ± 1 kg) were utilized in a generalized randomized block design. Two experimental treatment strategies were used to determine steer morbidity, whereby pen-riders evaluated the cattle and made the decision on when to treat (Pen-Rider) compared to the remote sensing tag that solely identified and flagged cattle in need of treatment (TAG). Steers were weighed on arrival to establish initial BW. Steers were assigned to one of two treatments based on their order through the chute. The receiving trial lasted 35 days with 6 days of limit feeding followed by 2 consecutive d weights to determine the ending BW. No differences were observed in ending BW, average daily gain (ADG), dry matter intake (DMI), and feed efficiency (P > 0.10). The proportion of steers being treated one or more times was greater with the TAG treatment vs pen-rider (42.2% vs 31.7%, respectively; P = 0.01). Similarly, a greater percentage of TAG steers were treated two or more times (10.1% vs 4.5%, respectively; P = 0.01), while no difference was detected for those treated three times (P = 0.10). However, the average temperature at the first treatment was the same across treatments (P = 0.95).

Following the receiving phase, the 180-day finishing phase started. No differences were observed in final BW, DMI, ADG, feed efficiency, and hot carcass weight (P > 0.10). However, 12th rib fat thickness was greater (P < 0.01) for steers on the Pen-Rider treatment. The proportion of steers treated two or more times (18.8% vs. 9.4%; P < 0.01) and three or more times (13.4% vs. 2.8%; P < 0.01) was greater for the TAG treatment compared to the Pen-Rider treatment, while the proportion treated at least once (P = 0.18) and the average temperature at the first treatment did not differ (P = 0.59). The percentage of steers with lungs containing severe fibrin tags was reduced with TAG (25.7%) compared to Pen-Rider (34.4%) while the percentage of lungs with normal fibrin tags was increased with TAG (51.8%) compared to Pen-Rider (41.9%; P = 0.02) while the percentage of contaminated lungs and lungs with consolidation did not differ (P > 0.59). These results indicate that the remote sensing ear tag increased the rate at which cattle were pulled for treatment but did not influence overall performance or carcass characteristics. The reduction in severe lung fibrin tags may impact late day deaths of feedlot steers in larger populations. The TAG appears to be viable a viable option to identify sick animals during the feedlot production phase.

Introduction

Health challenges in feedlot cattle continue to limit both efficiency and profitability in the beef industry. Losses from illness and death reduce overall performance and contribute to significant financial risk for producers (Griffin, 1997; Schneider et al., 2009). Stressors associated with transport, diet transition, and comingling are problematic because these factors occur when cattle are most vulnerable to respiratory disease and other health concerns (Loerch and Fluharty, 1999; J C Swanson and J Morrow-Tesch, 2001). Animal health issues are especially important today because the value of cattle and days on feed are increasing, whereas herd numbers are declining, thereby amplifying the importance of monitoring animal health.

 

Detecting illness at an early stage is critical to reducing the negative impacts on performance later in the feeding period. However, cattle often mask symptoms, making it difficult for pen-riders to identify a disease early on. With fewer personnel available to evaluate cattle, there is an increasing likelihood that there will be a delay in treatment. In response to this issue, technologies have been designed to continuously monitor cattle. Wearable devices can track physiological or behavioral changes, such as rumination or body temperature. This gives the ability to try and identify health problems before they are able to be seen by feedlot personnel. These systems could give more consistent and unbiased information than just observing the cattle, which may help feedlot personnel make better decisions and treat animals more accurately. However, before they are used in commercial operations, the technology needs to show that it is reliable, affordable, and as accurate or more accurate than the pen-riders. Therefore, the objective of this experiment was to evaluate the effectiveness of a wearable tag on the detection of animal health, receiving calf performance, and finishing performance.

Materials and Methods

A feedlot study was conducted at the University of Nebraska-Lincoln Eastern Nebraska Research, Extension, and Education Center (ENREEC) near Mead, Nebraska. All procedures used in this experiment were reviewed and approved by the University of Nebraska-Lincoln Institutional Animal Care and Use Committee (IACUC #2226). Calf-fed steers (n=638; initial BW = 281 ± 1 kg) were used in a generalized randomized block design. The study consisted of two blocks based on arrival date, with processing occurring one week apart. Block one included two sources of cattle, while block two included three sources. A total of 40 pens were used in this study, with two treatments evaluated, with 16 steers per pen; however, two pens contained 15 steers due to the removal of two bulls at arrival.

 

Steers were sourced from North Dakota and Nebraska auction markets and transported to ENREEC. Upon arrival of the first source in block one, the steers were fed 4.5 kg of DM per head of grass hay and processed 14 hours later. The second source of block one arrived overnight and was processed six hours later; therefore, no grass hay was given. Upon arrival of the first source in block two, cattle were penned and given 4.5 kg of DM per head of grass hay and processed 20 hours later. The second source arrived and was penned and given 4.5 kg of DM per head of grass hay, and processed 20 hours later. The third source arrived and was penned and given 4.5 kg of DM per head of grass hay, and processed six hours later. During processing, steers were assigned to one of two treatments based on their order through the chute and stratified by BW. The initial BW was a single weight collected at processing.

 

All steers received a killed vaccine for clostridial toxins and histophulus somnus (Ultrabac 7/Somubac, Zoetis Inc, Florham Park, NJ), a modified live vaccine in prevention of IBR, BVD, PI3, and BRSV (BoviShield Gold, Zoetis Inc, Florham Park, NJ), an injectable solution for the treatment and control of gastrointestinal and external parasite control (Dectomaxx, Zoetis Inc, Florham Park, NJ), and an injectable control of lungworms, stomach worms, and intestinal worms (Safe-Guard, Merck Animal Health, Rahway, NJ). Cattle were fed a receiving diet for 35 days: 32% grass hay, 32% dry rolled corn, 32% sweet bran, and 4% supplement, which provided decoquinate (Deccox; Zoetis Animal Health, Florham Park, NJ) at 125 mg/hd/d and Monensin (Rumensin; Elanco Animal Health, Greenfield, IN) at 200 mg/hd/d (Table 1). All supplements were formulated to include 30 g/ton DM of monensin (Rumensin, Elanco Animal Health, Greenfield, IN) and to provide 8.8 g/ton DM of tylosin (Tylan, Elanco Animal Health).

 

Two experimental treatment strategies were used to determine steer morbidity, whereby pen-riders evaluated the cattle and made the decision on when to treat (Pen-Rider) or a remote sensing ear tag (HerdDogg, Seward, NE) that solely identified and flagged cattle in need of treatment (TAG). The tag is equipped with an accelerometer to identify sick animals. It uses an algorithm based on itself and pen-mates’ activity. Steers assigned to the Pen-Rider strategy were evaluated daily for signs of Bovine Respiratory Disease (BRD) using the Depression – Appetite – Respiration – Temperature (DART) method (Holland et al., 2010). In the pen-rider treatment, rectal temperatures had to be equal to or greater than 40.0°C or less than 37°C for steers to be treated. Rectal temperatures were recorded at the time of treatment. Steers that were on the pen-rider treatment were equipped with HerdDoggg tags, but they were not used in identifying sick cattle, and the animal health personnel did not have access to the information generated by the tag. In the TAG group, steers were treated when first flagged by the HerdDogg tag, regardless of DART criteria. Cattle observed for signs of BRD were treated with Tulathromycin (Draxxin, Elanco Animal Health, Greensfield, IN) or Tilipirosin (Zuprevo, Merck Animal Health, Rahway, NJ). Steers were observed after the first, and if they required another treatment, they were treated with Enrofloxacin (Baytril, Elanco Animal Health, Greenfield, IN). If steers required another treatment after the first two treatments, they were treated with Florfenicol (Nuflor, Merck Animal Health, Rahway, NJ). After 35 days, the cattle were limit fed at 2% of BW for six days with a diet of 50% sweet bran (Cargill Corn Milling, Blair, NE) and 50% alfalfa hay (DM basis) to minimize the effects of gut fill and obtain an accurate initial BW for the finishing period (Watson et al., 2013). Cattle were weighed for two consecutive days to determine BW (Stock et al., 1983). The first day, the cattle were individually weighed using a hydraulic squeeze chute (Silencer, Moly Manufacturing Inc., Loraine, KS) and revaccinated with BoviShield Gold (Zoetis Inc, Florham Park, NJ), Ultrabac 7/Somubac (Zoetis Inc, Florham Park, NJ), and implanted with 40 mg of estradiol and 200 mg trenbolone acetate (Revalor XS, Merck Animal Health, Rahway, NJ). For the receiving period, BW was averaged from the two days after subtracting initial body weight, and dividing by 41-day average daily gain was calculated. These weights were also used to calculate feed efficiency.

 

Health data was also collected for both treatment groups. The average number of treatments per pen was calculated by categorizing cattle based on the frequency of treatments, either once, twice, or three times. A retrospective analysis compared the agreement of the remote sensing tag with the treatments by the pen-riders in the pen-rider treatment pens. The comparison was organized into four categories: (1) treated and flagged, indicating that the steers received treatment from pen-riders and were identified by the HerdDogg tag, (2) flagged but not treated, indicating that the HerdDogg tag flagged but the steer was not identified by pen-riders, (3) treated but not flagged, indicating that pen-riders treated the steer, but the tag did not flag it, and

(4) not flagged and not treated, indicating that the pen-riders and tag identified the steer as healthy. Categories 1 and 4 indicate the proportion of steers that the tag and pen-riders agree; either sick and treated or no sick and not treated.

 

After a 41-day receiving period and weighing on two consecutive days, steers were adapted to the finishing ration over 24 days. During each step, 12% of HMC replaced 10% of the corn silage and 2% of the corn stalks, while the inclusion of the supplement (4%) and sweet bran (40%; Cargill, Blair, NE) remained constant. The final diet contained 51% HMC, 40% sweet bran, 5% corn stalks, and 4% supplement (Table 2). All supplements were formulated to include 30 g/ton DM of monensin (Rumensin, Elanco Animal Health, Greenfield, IN) and to provide 8.8 g/ton DM of tylosin (Tylan, Elanco Animal Health). Lubabegron (Experior, Elanco Animal Health, Greenfield, IN) and Ractopamine Hydrochloride (Optaflexx, Elanco Animal Health, Greenfield, IN) was fed the last 42 and 34 days on feed to target 36 mg/steer daily and 300 mg/steer daily, followed by a four-day and two-day withdrawal before slaughter, respectively.

 

Steers were fed once daily and managed for ad libitum intake. Feed bunks were evaluated each morning at approximately 0600 h, and refusals were removed when necessary. Daily feeding occurred at 0800 h, with rations delivered using a truck-mounted mixer and delivery unit (Roto-Mix, Dodge City, KS). Feed refusals were weighed, subsampled, and dried in a forced-air oven at 60 °C (model LBB2-21-1; Despatch Industries, Minneapolis, MN) for 48 h to determine DM and calculate the DM weight of refusals (AOAC, 199; method 4.1.03). Ingredient samples were sampled weekly for DM analysis, and as-fed ingredient inclusions were adjusted weekly. At the end of the trial, ingredient samples that were collected weekly were composited by month and sent to a commercial laboratory (Ward Laboratories, Kearney, NE) to be analyzed for DM, total starch, crude protein, neutral and acid detergent fiber, and minerals.

 

After 179 and 180 days on feed, cattle were shipped to a commercial abattoir (Greater Omaha, Omaha, NE). On the day of harvest, kill order and hot carcass weight (HCW) were recorded. Liver and lung scores were also recorded on the day of harvest. The scoring system used was: 0 for no liver abscesses, A- for many large abscesses, A for one large abscess or a few small abscesses, and A+ for many large abscesses (Brink et al., 1990). Lungs were evaluated, and each animal was assigned a score based on the extent of lung consolidation and presence of fibrin tags. Lungs were classified as: Normal (healthy lungs <5% consolidation and without fibrin tags), Minor (presence of minor fibrin tags), Extensive (presence of extensive fibrin tags), 1 (5-15% consolidated lung tissue), 2 (15-50% consolidated lung tissue), 3 (>50% consolidated lung tissue) (Tennant et al., 2014). The final BW was calculated using a common dressing percentage of 63%. Carcass adjusted final BW was used to determine ADG and G:F. Following a 48-h chill, USDA marbling score, longissimus muscle (LM) area, and 12th rib fat thickness were recorded. Yield grade was calculated using the USDA (1997) YG equation: YG = 2.5 + (2.5 x 12th rib fat, cm) + (0.2 x 2.5) + (0.0038 x HCW, kg) – (0.32 x LM area, cm2). It was an assumed average KPH of 2.5%.

 

Performance data were analyzed using the Mixed Procedure of SAS (SAS Institute, Inc., Cary, N.C.). Pen was the experimental unit, and treatment and block were fixed effects. Frequency of lung consolidation and fibrin presence were analyzed using multinomial mixed models. Presence on lung contamination was determined using a binomial mixed model. For performance and carcass traits, data were analyzed as a 2x2 factorial, whereby interactions were evaluated and main effects of either health data or feed additive. For all variables except fat depth, no significance was detected. Due to unequal replications within weight blocks within each arrival block, arithmetic means were shown as LSmeans were adjusted for different starting weight block replications. The treatment effects are the same whether LSmeans or arithmetic means are presented. Significance was declared when a P < 0.05, with tendencies declared at P < 0.10. 

Results and Discussion

Receiving Phase

Cattle fed on both treatments had similar initial body weight, average daily gain, feed efficiency, and ending body weight for the first 41-d following receiving and throughout the trial (Table 3). For the health outcomes, a greater percentage of steers in the TAG treatment were treated one or more times compared to the Pen-Rider cattle (42.2% vs. 31.7%, respectively; P = 0.01, Table 4). The percentage of steers treated two or more times tended to be greater for TAG treatment compared to the Pen-Rider treatment (10.1% vs. 4.5%, respectively; P = 0.01). Additionally, a greater proportion of the cattle on the TAG treatment were treated three times compared to cattle on the Pen-Rider treatment (1.3% vs. 0.2%, respectively; P = 0.10). These values were calculated by dividing the number of cattle treated by the initial number of head assigned to each pen. In pens where the pen-riders made the treatment decision, agreement between the tag and pen-rider observations were limited. The pen-riders and tag agreed 43.7% of the time. Within that percentage, it can be shown that 23.7% of the steers were treated and flagged by the pen-riders (Table 5), and 20% of the cattle were neither flagged nor treated, indicating there was agreement that the steers did not experience illness. Conversely, 42.1% of the steers were flagged by the tag but the pen-riders did not treat. However, within this category, it is difficult to assess how many steers needed treatment. The tag was shown to miss steers that were presumed sick by the animal health personnel with a percentage of 14.2%. When the tag and pen-riders both identified the same sick steers within a 7-day window, the tag detected illness an average of one day earlier (32%, percent of pen). If cattle were treated outside of the 7-day agreement period, pen-riders identified sick cattle an average of 12 days earlier, suggesting that there were some calves that were missed by the tag or steers that were misdiagnosed by animal health personnel. Rectal temperature was recorded for cattle in both treatments, and no difference was found in the average rectal temperature at the first treatment (40°C, P = 0.95, Table 4). There are no differences (P = 0.71) for the standard deviation of temperature at the first treatment between the two treatment groups.

Finishing Period

Steers fed during the finishing period had similar initial body weight, final body weight, dry matter intake, average daily gain, feed efficiency, hot carcass weight, ribeye area, marbling score, 12th rib fat thickness, calculated yield grade, and liver abscess (P > 0.05; Table 6). Steers also had similar USDA Yield Grade and Quality Grade distribution (P > 0.53; Table 7). For the health outcomes, a similar percentage of steers in the TAG treatment were treated one or more times compared to the Pen-Rider cattle (21.6% vs. 17.2%, respectively; P = 0.18, Table 4). The percentage of steers treated two or more times was greater for TAG treatment compared to the Pen-Rider treatment (18.8% vs. 9.4%, respectively; P < 0.01). Additionally, a greater proportion of cattle on the TAG treatment were treated three times compared to cattle on the Pen-Rider treatment (13.4% vs. 2.8%, respectively; P < 0.01). The values were calculated by dividing the number of cattle treated by the initial number of head assigned to each pen. In pens where the pen-riders made the treatment decision, agreement between the tag and pen-rider observations were limited. The pen-riders and tag agreed 62.4% of the time. Within that percentage, it can be shown that 10% of the steers were treated and flagged by the pen-riders (Table 8), and 52.4% of the steers were neither flagged nor treated, indicating that there was agreement that the steers did not experience illness. It was shown that 25.7% of the steers were flagged by the tag but the pen-riders did not treat. However, within this category, it is difficult to assess how many steers needed treatment. The tag was shown to miss steers that were presumed sick by the animal health personnel with a percentage of 11.9%. By using these numbers, it was found that if the tag flagged and the pen-riders agreed that an animal was sick within 7 days of each other, the tag identified that cattle 1 day earlier than the pen-riders (52%, percent of pen). If cattle were treated outside of the 7-day agreement period, the tag identified the steers one day earlier than the pen-riders. Rectal temperature was recorded at the first treatment was similar in the TAG treatment vs. the Pen-Rider treatment (39.89°C vs. 39.94°C, respectively; P = 0.59, Table 6). There was no difference (P = 0.18) for the standard deviation of temperature at the first treatment between the two treatment groups.

Whole Feeding Period

Health outcomes were calculated for the whole feeding period. It was found that are greater percentage of steers in the TAG treatment were treated one or more times compared to the Pen-Rider cattle (64.1% vs. 49.4%, respectively; P < 0.01, Table 4). The percentage of steers treated two or more times was greater for the TAG treatment compared to the Pen-Rider treatment (29.1% vs. 14.1%, respectively; P < 0.01). Additionally, a greater proportion of the cattle on the TAG treatment were treated three times compared to the cattle on the Pen-Rider treatment (13.4% vs. 2.8%, respectively; P < 0.01). These values were calculated by dividing the number of cattle treated by the initial number of head assigned to each pen. In pens where the pen-riders made the treatment decision, agreement between the tag and pen-rider observations were limited. The pen-riders and tag agreed 48.3% of the time. Within that percentage, it can be shown that 37.9% of the steers were treated and flagged by the pen-riders (Table 9), and 10.4% of the cattle were neither flagged nor treated, indicating there was agreement that the steers did not experience illness. Conversely, 37.6% of the steers were flagged by the tag but the pen-riders did not treat. However, within this category, it is difficult to assess how many steers needed treatment. The tag was shown to miss steers that were presumed sick by the animal health personnel with a percentage of 14.1%.

When the tag and pen-riders both identified the same sick steers within a 7-day window, the tag detected illness an average of two days earlier (29%, percent of pen). If cattle were treated outside of the 7-day agreement period, pen-riders identified sick cattle an average of two days earlier, suggesting that there were some calves that were missed by the tag or steers that were misdiagnosed by animal health personnel. Rectal temperature was recorded at the first treatment was similar in the TAG treatment vs. the Pen-Rider treatment (39.83°C vs. 40°C, respectively; P = 0.14, Table 6). There was no difference (P = 0.18) for the standard deviation of temperature at the first treatment between the two treatment groups. Additionally, lung scores were collected on each animal during harvest. It was found that there is a significant shift in the distribution of percentage of fibrin scores across treatment. Steers on the TAG treatment had increased normal (51.8% vs. 41.9%; respectively) and extensive (25.7% vs. 34.4%; respectively; P < 0.02; Table 10) fibrin scores compared to the pen-rider treatment. There was no difference in percentage of lung consolidation (P < 0.59; Table 11) and lung contamination (P < 0.81; Table 12). These results may indicate that detecting sick steers may improve lungs scores ultimately leading to fewer late day deads.

 

Findings in this study agree with previous research conducted by Schupbach et al. (2025) that examined the use of SenseHub Feedlot (Merck Animal Health, Rahway, NJ) technology compared to traditional pen riders. They found that when cattle are monitored via technology, it is faster for cattle to receive their first BRD treatment, fewer pen deads, and fewer overall removals. In the current study, no difference was noticed for pen deads and overall removals, but it was noticed that a higher percentage of animals were pulled using technology, indicating that cattle may receive treatment for BRD faster than traditional ways.

 

In the current study, cattle monitored with the HerdDogg tag were treated more frequently than those identified through pen-rider detection, with a greater proportion of those animals requiring multiple treatments across the receiving, finishing, and overall feeding period. These results are similar to a study done by White et al. (2015), where the remote early disease identification (REDI) system detected cattle earlier than visual checks and cut down on antibiotic use, but it flagged more cattle for treatment without improving performance. In another study, Smith et al. (2015) used an electronic ear tag that tracked steer movement with accelerometers to see if sick cattle had changes in their behavior. They found that steers that were sick had about 25% less activity than healthy steers. This is similar to the HerdDogg tag, as it also utilizes deviations in activity to determine if an animal is sick. Qumiby et al., (2001) looked at a feeding behavior system (Growsafe® Ltd., Airdrie, AB) along with pen-riders to determine illness. The data was analyzed using a cumulative sum chart, and it showed that using bunks that show an animal’s eating behavior could predict the onset of disease an average of 4 days earlier than traditional pen-riders. However, it was assumed that the pen-riders were correct if they identified an animal as sick. Similarly, Wolfger et al., (2015) looked at feeding behavior, especially meal intake, meal duration, and number of meals. It was found that calves that developed BRD showed reduced meal size, fewer meals per day, and shorter meal duration several days before they were identified as sick by feedlot personnel. While neither study used electronic ear tags to detect morbidity, both show that using technology like monitoring feeding behavior can identify illness earlier than conventional methods.

Conclusions

Overall, the tag detected cattle 1-2 days earlier than the pen-riders. Both treatments resulted in similar performance and carcass characteristics. The HerdDogg tag is a valuable tool to support decision-making when identifying sick animals.

Literature Cited

  1.  Brink, D. R., S. R. Lowry, R. A. Stock, and J. C. Parrott. 1990. Severity of liver abscesses and efficiency of feed utilization of feedlot cattle. J. Anim. Sci. 68:1201–1207. doi:10.2527/1990.6851201x.
  2. Griffin, D. 1997. Economic impact associated with respiratory disease in beef cattle. Vet. Clin.
    North Am. Food Anim. Pract. 13:367–377. doi:10.1016/s0749-0720(15)30302-9.
  3.  Holland, B. P., L. O. Burciaga-Robles, D. L. VanOverbeke, J. N. Shook, D. L. Step, C. J. Richards, and C. R. Krehbiel. 2010. Effect of bovine respiratory disease during preconditioning on subsequent feedlot performance, carcass characteristics, and beef attributes1,2. J. Anim. Sci. 88:2486–2499. doi:10.2527/jas.2009-2428.
  4.  J C Swanson and J Morrow-Tesch. 2001. Cattle transport: Historical, research, and future perspectives. J. Anim. Sci. 79:E102--. doi:10.2527/jas2001.79e-supple102x. 
  5.  Loerch, S. C., and F. L. Fluharty. 1999. Physiological changes and digestive capabilities of newly received feedlot cattle. J. Anim. Sci. 77:1113–1119. doi:10.2527/1999.7751113x. 
  6.  Quimby, W.. F., B. F. Sowell, J. G. Bowman, M. E. Branine, M. E. Hubbert, and H. W. Sherwood. 2001. Application of feeding behaviour to predict morbidity of newly received calves in a commercial feedlot. Can. J. Anim. Sci. 81:315-320. doi:10.4141/A00-098. 
  7.  Schneider, M. J., R. G. Tait Jr., W. D. Busby, and J. M. Reecy. 2009. An evaluation of bovine respiratory disease complex in feedlot cattle: Impact on performance and carcass traits using treatment records and lung lesion scores1,2. J. Anim. Sci. 87:1821–1827. doi:10.2527/jas.2008-1283. 
  8.  Schupbach, B. S., M. S. Davis, T. D. Jennings, A. L. Dixon, D. G. Renter, and J. S. Nickell. 2025. Comparison of a novel bovine respiratory disease prediction technology and an automated animal disease detection technology to traditional methods in a U.S. feedlot. Transl. Anim. Sci. 9:txaf067-. doi:10.1093/tas/txaf067.
  9.  Smith, J. L., E. S. Vanzant, C. N. Carter, and C. B. Jackson. 2015. Discrimination of healthy versus sick steers by means of continuous remote monitoring of animal activity. Am. J. Vet. Res. 76:739–744. doi:10.2460/ajvr.76.8.739.
  10.  Stock, R., T. Klopfenstein, D. Brink, S. Lowry, D. Rock, and S. Abrams. 1983. Impact of weighing procedures and variation in protein degradation rate on measured performance of growing lambs and cattle. J. Anim. Sci. 57:1276–1285. doi:10.2527/jas1983.5751276x. 
  11.  Tennant, T. C., S. E. Ives, L. B. Harper, D. G. Renter, and T. E. Lawrence. 2014. Comparison of tulathromycin and tilmicosin on the prevalence and severity of bovine respiratory disease in feedlot cattle in association with feedlot performance, carcass characteristics, and economic factors. J. Anim. Sci. 92:5203–5213. doi:10.2527/jas.2014-7814.
  12. Watson, A. K., B. L. Nuttelman, T. J. Klopfenstein, L. W. Lomas, and G. E. Erickson. 2013.
    Impacts of a limit-feeding procedure on variation and accuracy of cattle weights. J. Anim. Sci. 91:5507-. doi:10.2527/jas.2013-6349.
  13.  White, B. J., D. E. Amrine, and D. R. Goehl. 2015. Determination of value of bovine respiratory disease control using a remote early disease identification system compared with conventional methods of metaphylaxis and visual observations. J. Anim. Sci. 93:4115-. doi:10.2527/jas.2015-9079.
  14. Wolfger, B., K. S. Schwartzkopf-Genswein, H. W. Barkema, E. A. Pajor, M. Levy, and K. Orsel.
    2015. Feeding behavior as an early predictor of bovine respiratory disease in North American feedlot systems. J. Anim. Sci. 93:377-385. doi:10.2527/jas.2013-8030.

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