E. D. Janzen

Pain mitigation after band castration of beef calves and its effects on performance, behavior, Escherichia coli, and salivary cortisol

Eighty-nine steer and bull calves (210 +/- 20 d of age) were randomly assigned to a 2 x 2 factorial arrangement of treatments to study the effect of sham or band castration (CAST) with or without pain medication (MED) on performance, behavior, cortisol, and Escherichia coli shedding. Steers (serving as controls; C) were previously castrated at 34 +/- 10 d of age, whereas bulls (B) remained intact until band application on d 20 of the experiment. One-half of the calves in each group received pain medication (M; xylazine epidural and intravenous flunixin meglumine) or saline (NM) solutions at 0.5 h before castration. Feed intake, ADG, and feeding behavior were measured over a 3-wk period before (used as covariates) and a 6-wk period after castration. Fecal and saliva samples were collected from 32 calves for E. coli enumeration at -7 (covariate), 2, 5, and 7 d, and for cortisol concentration at -0.5 (covariate), 0, 0.5, 1, 2, 4, 24, 48, 168, and 336 h relative to castration, respectively. Lying behavior was measured in the home pen and step length at exit from the chute. There were no significant CAST x MED interactions on growth rate or feed intake. Overall ADG was less in B compared with C (P < 0.001), but feed intake was less during wk 4 only (P = 0.01). On average, M had less intake (P = 0.02) and eating rate (P = 0.04) than NM calves. The BM had less fecal E. coli counts than CM (P = 0.05) and castrated and nonmedicated calves (P = 0.08). Salivary cortisol was less in BM compared with the rest of treatments at 1 and 2 h after banding (P <or= 0.05). Castration reduced time spent lying (P = 0.06) and step length (P = 0.01) until d 28 after banding, whereas M reduced lying and step length on day of banding only (P <or= 0.06). Significant CAST x MED interactions were observed for frequency of visits to feeders and meal size, length, and frequency (P < 0.05) independent of the time after castration. This was due to greater values in the noncastrated and non-pain-medicated group compared with the rest, except for reduced meal frequency, indicating that pain medication and castration both affected feeding behavior. The medication protocol used in the present study eliminated the acute cortisol surge, which may be linked to reduced fecal E. coli counts observed during wk 1 after banding. However, feed intake, growth, and behavior suggested that pain was greatest during wk 3 and 4 after band application, which highlights the need for chronic pain mitigation strategies.

Effects of branding on weight gain, antibiotic treatment rates and subsequent handling ease in feedlot cattle

Two trials were conducted to investigate the effects of hot-iron and freeze branding on individual body weight (BW) antibiotic treatment (AT) rates based on rectal temperature (RT), and subsequent handling ease in feedlot cattle. Charolais-cross steer calves were ear-tagged and vaccinated on arrival to the feedlot and assigned to freeze brand (F), hot-iron brand (H), or control (C) treatments. Animals were branded at arrival to the feedlot in Trial 1 (n = 300) and 20 d after arrival in Trial 2 (n = 248). Rectal temperatures, AT and BW of all animals were recorded on the day of branding and every second day for 10 d. Branding treatments had no effect on average daily gain (ADG) or AT rates in either trial. Steers in Trial 2 required increased handling pressure over the 10 d period, indicating some aversion to being caught in the chute for measurement of RT. The only effect of treatment on handling ease was that freeze branded steers required more (P < 0.005) handling pressure than C or H steers on d 6 afte...

Effects of castration method and frequency of intramuscular injections of ketoprofen on behavioral and physiological indicators of pain in beef cattle

Two experiments were conducted to determine the effect of a single or multiple intramuscular (i.m.) injection of ketoprofen and castration technique on physiological and behavioral indicators of pain in beef calves. A total of 150 bull calves (284.8 ± 22.7 kg BW) were used in both experiments, each 1 conducted as a 3 × 2 factorial design, where main factors included castration technique--no castration (CT), surgical (SU), or band (BA)--and drug administration--physiological solution (PS) or i.m. injection of ketoprofen (KP; 3 mg Anafen/kg BW) in the neck of calves. Animals were weighed weekly during the experiment to calculate ADG. Behavioral responses indicative of pain and discomfort during the castration procedure were documented using a visual analog score (VAS) by an experienced observer who was blind to the treatments. Movements of the animals in the chute during castration were quantified using a strain gauge system mounted on the head gate to evaluate the escape response of the cattle. Pens were equipped with an automated feed bunk monitoring system enabling feed intake and feeding behavior to be continuously monitored for each individual. Thermographic images of the scrotal area were evaluated 24 and 0.5 h before castration, 0.5, 1, 24, 48, and 270 h postcastration, and weekly thereafter until the end of the trial. Blood samples were obtained postcastration to evaluate changes in total white blood cell (WBC) count and neutrophil-to-lymphocyte (N:L) ratio. Saliva samples were taken 24 and 0.5 h before castration, immediately after castration, and 0.5, 1, 2, 5, 24, and 48 h and then 5, 7, and 14 d after castration to determine cortisol concentration. Scrotal temperature, VAS, total WBC, N:L ratio, salivary cortisol, mobility, and pressure exerted in the chute were greater (P < 0.05) and ADG and feed intake were lower (P < 0.05) in SU than in CT animals within the first week after castration. Also, BA calves had a greater (P < 0.05) scrotal temperature around wk 4 after castration and a lower feed intake and ADG at wk 2 and 3 and wk 6 and 7 after castration, respectively, compared to CT. Treatment KP had limited effects on reducing the indicators of pain associated with SU or BA, suggesting that further studies will be needed to assess the posology of the i.m. administration of ketoprofen to improve the consistency of its effects as a pain mitigation strategy after castration.

Effect of anti-gonadotropin-releasing factor vaccine and band castration on indicators of welfare in beef cattle

Angus crossbred bulls (n = 60; 257 ± 5.4 d of age; initial BW 358.8 ± 3.78 kg) were used to study the effect of a vaccine against gonadotropin-releasing factor (GnRF) and band castration on behavioral and physiological indicators of pain. Cattle were randomly assigned to 1 of 3 treatments: bulls, band-castrated calves without pain mitigation (castrated), and immune-vaccinated animals administered an anti-GnRF vaccine (vaccinated). All animals were fitted with a radio frequency ear tag so that individual animal feed intake and feeding behavior were recorded daily over the entire trial using an electronic feed bunk monitoring system. Two doses of anti-GnRF vaccine were administrated on d -35 and 0 and band castration was performed on d 0. Animal BW was recorded weekly starting on d -36 until d 56. Visual analog scores (VAS) were measured on d -36 -35, -1, and 0, and salivary cortisol concentration was measured at -30, 0, 30, 60, 120, and 270 min on d -35 and 0 after castration. Saliva and blood were obtained on d 1, 2, 5, and 7 and weekly until d 56 for determination of cortisol and complete blood cell count. Video data were collected for pain, sexual, and aggressive behavior daily the first week and once a week until d 56. Data were analyzed with a mixed-effect model with castration, time, and their interactions as main effects. Vaccinated calves had reduced ADG and intake (P < 0.05 and P < 0.001, respectively) during the first week after vaccination. Band-castrated calves had reduced ADG and intake (P < 0.001) until the end of the study. No differences in salivary cortisol and VAS were observed among groups at d -35 after the first vaccination and before band castration. However, on d 0, castrated cattle had greater cortisol concentrations and VAS (P < 0.05 and P < 0.01, respectively) than bulls and vaccinated animals. Complete blood cell count did not differ (P > 0.05) between treatments on d 0, 1, and 2. At d 56, vaccinated calves had greater (P < 0.05) final BW than band-castrated calves and both had less final BW than bulls. There was no indication that vaccination caused any physiological or behavioral changes indicative of pain. In contrast, band castration resulted in elevated cortisol scores and VAS indicative of a pain response and behavior related to pain (P < 0.001) until d 42 of the study. The present study demonstrates that anti-GnRF vaccine is a viable animal welfare-friendly alternative to traditional band castration in beef cattle under North American feedlot practices.

Trailer temperature and humidity during winter transport of cattle in Canada and evaluation of indicators used to assess the welfare of cull beef cows before and after transport.

The current study evaluated 17 loads of cull beef cows transported in Canadian winter conditions to assess in-transit temperature and humidity, evaluation of events during loading and unloading, and animal condition and bruising. Regardless of the use of boards to block ventilation holes in trailers, temperatures were higher within trailers than at ambient locations during both travel and stationary periods (P < 0.01). Boarding was associated with smaller differences in trailer temperature, compared with ambient conditions, while the trailer was traveling at highway speeds versus when trailers were stationary (P < 0.01). Moisture levels within trailers were not different from ambient conditions when loads using boarding were traveling (P < 0.01), whereas loads without boarding had a larger difference (P < 0.01). The moisture within trailers relative to ambient conditions increased when trailers were stationary compared with traveling when boarding was used (P < 0.01). The majority of cattle transported were in good body condition (97.4% within BCS of 2 to 3.5) and had calm temperaments (96.7%). Although all comparisons were made, only the doghouse compartment had an increased risk of severe bruising compared with all other compartments (odds ratio [95% confidence interval]: 3.0 [1.6–5.5], 3.7 [2.1–6.4], 2.2 [1.3–3.7] and 3.8 [1.5–9.6] in comparison with the back, belly, deck, and nose compartments, respectively; P < 0.05). Increasing the duration of waiting to unload 30 min relative to a 1 h duration increased the odds of severe bruising by 1.18 times (95% confidence interval: 1.09–1.29; P < 0.01). Scoring systems that have been developed for auditing unloading of cattle had limited variation across loads at both loading and unloading. Pretransport assessment of animal condition using the American Meat Institute’s compromised animal score was the only scoring system that was consistent with posttransport scores. We inferred from the temperature and humidity data in the current study that under commercial conditions, boarding may increase ventilation within trailers during travel and decrease ventilation during stationary periods. The current study provides the first indication that issues in Canadian cull cow transport may be related to pretransport animal condition and management of unloading.

Effect of band and knife castration of beef calves on welfare indicators of pain at three relevant industry ages: I. Acute pain

Three experiments evaluated the effect of band and knife castration on acute pain for the first 7 d after the procedure on 1-wk-, 2-mo-, and 4-mo-old calves. All calves were blocked by age and weight and randomly assigned to 1 of 3 treatments: sham castration (control, CT), band castration (BA), and knife castration (KN). Experiment 1 evaluated 1-wk-old Angus bull calves ( = 34; 43.0 ± 6.61 kg BW), Exp. 2 evaluated 2-mo-old Angus bull calves ( = 34; 91.5 ± 11.93 kg BW), and Exp. 3 evaluated 4-mo-old Angus bull calves ( = 35; 157.6 ± 22.52 kg BW). For all experiments, physiological and behavioral parameters were collected before (d -1 and immediately before castration [T0]) and after (60 and 120 min and on d 7) castration to assess acute pain. Physiological measures included complete blood cell count, cortisol, substance P, and scrotal temperature. Behavioral measures consisted of a visual analog scale, stride length, and time and frequency budgets for walking, standing, lying, tail flicking, foot stamping, and head turning. Performance parameters included initial and final BW and ADG. In Exp. 1, tail flicking was greater ( = 0.02) in KN calves compared to BA calves 2 to 4 h after castration, although no differences were seen between BA and KN compared to CT calves. In Exp. 2, a treatment × time interaction ( = 0.02) was observed for cortisol, where KN calves had greater cortisol concentrations 120 min after castration compared to BA and CT calves; KN calves also lay down and ate less ( < 0.01; = 0.02) and stood and walked more ( < 0.01; = 0.05) compared to BA and CT calves 2 to 4 h after castration. In Exp. 3, a treatment × time interaction ( < 0.01) was observed for cortisol concentrations in which all treatments were different from one another at 60 and 120 min, with BA calves having the greatest concentrations, KN calves being intermediate, and CT having the lowest concentrations. Overall, KN and BA castrated calves presented physiological and behavioral changes associated with acute pain; however, 2-mo-old BA calves presented the fewest behavioral changes and no physiological changes associated with acute pain compared to CT calves.

Trailer microclimate during commercial transportation of feeder cattle and relationship to indicators of cattle welfare

Nineteen loads of commercial feeder cattle (BW 376 ± 39 kg, mean ± SD) transported for 18 ± 4.5 h in summer and winter seasons were used to collect data on internal temperature and humidity conditions in the deck and belly compartment of pot-bellied trailers and their relationship with shrink, cortisol, and morbidity. Measurements of temperature or humidity at ceiling or animal level did not vary with transportation factors. Temperature and humidity ratio was greater at animal-level than ambient conditions during nonhighway travel and stationary periods (P < 0.01). During the 3 time periods evaluated within journeys, there was a larger difference between animal-level and ambient conditions during the winter than during the summer (P < 0.01); however, this difference was not associated with other transport factors (P > 0.05). Evening loads (1700 and 2100 h) experienced more shrink in the summer than in the winter (11.2 ± 0.5 vs. 9.0 ± 0.5% of BW; P = 0.03). A 1°C increase in difference between average animal-level temperature in transit and the mean ambient temperature during the 10 d before transport was associated with a 0.11 ± 0.03% of BW increase in shrink (P < 0.01) and 0.006 ± 0.002 ng/mL increase in posttransport cortisol concentration (P = 0.05). Animal-level temperature-humidity index (THI) events (consecutive observations of THI greater than 78°F) were more likely to last for longer than 1 h when the trailer was stationary vs. traveling (mean = 1.8, confidence level 95% = 1.33, 2.52). During THI events at animal level, the disagreement with ambient temperature regarding THI classification was lower when the vehicle was traveling vs. stationary (95.5 ± 0.01% vs. 99.7 ± 0.002% of THI event in disagreement; P < 0.01) and was greatest in events less than 1 h (99.8 ± 0.0% vs. 91.7 ± 0.03% of THI event in disagreement; P < 0.01). The average magnitude of the difference during these events was 11.4 ± 7.6°F and was not affected by transportation factors (P > 0.05). Despite association between indicators of calf welfare and microclimate, all cattle arrived in good condition and there was 0.96% treatment rate within the first 30 d after arrival. Management and auditing decisions related to transportation of feeder cattle should consider the relationship between animal-level and ambient conditions and conditions before transportation. Under the commercial conditions of the current study, the transportation process did not appear to cause distress according to the dimensions of animal welfare that were assessed.

Comparison of eight logger layouts for monitoring animal-level temperature and humidity during commercial feeder cattle transport12

Measuring animal-level conditions during transit provides information regarding the true risk of environmental challenges to cattle welfare during transportation. However, due to constraints on placing loggers at the animal level, there is a need to identify appropriate proxy locations. The objective was to evaluate 8 distributions of ceiling-level loggers in the deck and belly compartments of pot-belly trailers for assessing animal-level temperature and humidity during 5 to 18 h commercial transportation of feeder cattle. Ambient conditions during transportation ranged from 3.6 to 45.2°C (20.3 ± 7.61°C, mean ± SD). When considering the entire journey, average differences between ceiling and animal-level temperatures were similar among logger layouts (P > 0.05). The uncertainty in the difference in temperature and humidity between locations was high relative to the magnitude of the difference between animal- and ceiling-level conditions. Single-logger layouts required larger adjustments to predict animal-level conditions within either compartment, during either the entire journey or when the trailer was stationary (P < 0.05). Within certain logger layouts, there were small but significant differences in the ability of regression equations to predict animal-level conditions that were associated with cattle weight and available space relative to body size. Furthermore, evaluation of logger layouts based solely on the entire journey without consideration of stationary periods did not adequately capture variability in layout performance. In conclusion, to adequately monitor animal-level temperature and humidity, 10 loggers distributed throughout the compartment was recommended over single-logger layouts within both the deck and belly compartments of pot-belly trailers transporting feeder cattle in warm weather.

Effect of timing of subcutaneous meloxicam administration on indicators of pain after knife castration of weaned calves1

The newly revised Canadian Codes of Practice for the management of beef cattle requires that as of 2018, calves older than 6 mo of age be castrated using pain control. Castration is a husbandry procedure commonly done without pain control, and there is a lack of agreement on an effective pain mitigation strategy specific to castration. The aim of this study was to identify the optimal time of administration of meloxicam prior to castration. Thirty-four Angus and Angus crossbred bull calves (282 ± 28.0 kg BW) were randomly assigned to 1 of 3 treatments receiving a single s.c. injection of meloxicam (0.5 mg/kg BW): 6 h (6H; = 11), 3 h (3H; = 12), or immediately (0H; = 11) before knife castration. Measurements included visual analog scale (VAS), head movement (HM), accelerometer movement (AM) and strain gauge exertion force (EF) on the squeeze chute, stride length (SL), lying and standing behavior, salivary cortisol (SC), haptoglobin, serum amyloid A (SAA), substance P (SP), and scrotal temperature (ST). Samples were collected on d -7, -5, -2, -1, and immediately before castration (T0) and 30, 60, 120, and 240 min and 1, 2, 5, 7, 14, 21, and 28 d after castration, except for VAS, AM, EF, and HM, which were obtained at the time of castration. A time × treatment effect ( = 0.01) was observed for SP, where 0H had lower concentrations than 3H and 6H calves 1 d after castration, whereas 3H calves tended to have greater levels than 6H calves 5 d after castration. Mean ST was greater ( < 0.01) in 6H calves compared to 0H and 3H calves 120 min after castration, whereas 6H and 3H calves had greater ST compared to 0H calves 240 min after castration. On d 1 after castration, 6H calves had greater ST than 0H and 3H calves, whereas 0H calves had greater ST compared to 3H and 6H calves on d 28 after castration. The SL tended ( = 0.09) to be shorter in 3H and 6H calves than 0H calves 30, 60, 120, and 240 min after castration. Number of peaks from the AM between 2 and 3 SD above or below the mean were greater ( = 0.03) in 3H and 6H calves than in 0H calves. No treatment differences ( > 0.10) were observed for the number of peaks and area for AM and EF, VAS, HM, SC, or haptoglobin. On the basis of these results, the optimal time to administer s.c. meloxicam in 7- to 8-mo-old knife-castrated calves is immediately before castration (0H), as evidenced by fewer indicators of pain and inflammation compared to 3H and 6H calves.

Effect of a single dose of meloxicam prior to band or knife castration in 1-wk-old beef calves: I. Acute pain

In Western Canada, approximately half of the calves produced are castrated before 1 wk of age. Therefore, it is important to identify effective analgesic drugs to mitigate pain associated with castration and consequently improve animal welfare. The aim of this study was to assess the efficacy of a single s.c. dose of meloxicam at mitigating pain associated with knife and band castration in 1-wk-old calves. Seventy-two Angus crossbred bull calves (47.3 ± 6.70 kg of body weight (BW), 1 wk old) were used in a 3 × 2 factorial design where main factors included castration method-sham (CT), band (BA) or knife (KN) castration- and medication-lactate ringer (NM) or 0.5 mg/kg BW of meloxicam (M). Measurements included different physiological and behavioral parameters. Samples were collected on day -1, immediately before castration (T0); and 60, 90, and 120 min and 1, 2, 3, and 7 d after castration except for visual analog scale (VAS) which was collected at the time of castration. The salivary cortisol concentrations were greater (P = 0.04) in KN and BA calves than CT calves 60 min after castration, while 90 min after castration BA had greater concentrations than CT calves. Substance P concentrations were greater (P = 0.04) in NM calves than M calves on d 3 and 7 after castration. The serum amyloid-A (SAA) concentrations were greater (P = 0.05) in KN calves than BA and CT calves on days 0, 2, and 3, while BA calves had greater SAA concentrations on day 7 than KN and CT calves. The visual analog scores were greater (P < 0.01) in KN calves than BA, and in BA compared to CT calves. The KN calves tail flicked more (P < 0.01) than BA and CT calves, and NM calves tail flicked more (P = 0.03) than M calves. No castration or medication effect (P > 0.10) was observed for stride length, walking, standing, lying ventral, eating, foot stamping, head turning, lying and standing percentage, performance, platelets, or body temperature. Overall, knife castrated calves exhibited a greater acute pain response than band castrated calves. Meloxicam was able to reduce substance P concentrations, white blood cell counts and number of tail flicks after castration, suggesting that the drug was able to mitigate acute pain to some extent. However, meloxicam did not have an effect on the other physiological and behavioral parameters assessed.