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Background: Bovine respiratory disease (BRD) is a significant health problem in beef cattle production, resulting in considerable economic losses due to mortalities, cost of treatment, and reduced feed efficiency. The onset of BRD is multifactorial, with numerous stressors being implicated, including transportation from farms to feedlots. In relation to animal welfare, regulations or practices may require mandatory rest times during transportation. Despite this, there is limited information on how transportation and rest stops affect the respiratory microbiota. Results: This study evaluated the effect of cattle source (ranch-direct or auction market-derived) and rest stop duration (0 or 8 h of rest) on the upper respiratory tract microbiota and its relationship to stress response indicators (blood cortisol and haptoglobin) of recently weaned cattle transported for 36 h. The community structure of bacteria was altered by feedlot placement. When cattle were off- loaded for a rest, several key bacterial genera associated with BRD (Mannheimia, Histophilus, Pasteurella) were increased for most sampling times after feedlot placement for the ranch-direct cattle group, compared to animals given no rest stop. Similarly, more sampling time points had elevated levels of BRD-associated genera when auction market cattle were compared to ranch-direct. When evaluated across time and treatments several genera including Mannheimia, Moraxella, Streptococcus and Corynebacterium were positively correlated with blood cortisol concentrations. Conclusion: This is the first study to assess the effect of rest during transportation and cattle source on the respiratory microbiota in weaned beef calves. The results suggest that rest stops and auction market placement may be risk factors for BRD, based solely on increased abundance of BRD-associated genera in the upper respiratory tract. However, it was not possible to link these microbiota to disease outcome, due to low incidence of BRD in the study populations. Larger scale studies are needed to further define how transportation variables impact cattle health. [ABSTRACT FROM AUTHOR]

Consumers are increasingly concerned about the welfare of farm animals, especially during transportation. The Canadian transport regulations state that weaned cattle require an 8 h rest after 36 h of transport. There are, however, only a few studies that assess the effect of rest on the welfare of beef cattle. The aim of this study was to assess the effect of conditioning, source and rest on indicators of welfare in 7-8-month-old beef calves during long-distance transport. Treatments consisted of a 2 × 2 × 2 factorial design where the main factors were conditioning: conditioned (C; n = 160) or non-conditioned (N; n = 160); source: auction market (A; n = 160) or ranch direct (R; n = 160); and rest: 0 h (0 h; n = 160) or 8 h (8 h; n = 160). Means of non-esterified fatty acids (NEFA), serum amyloid-A, haptoglobin, creatine kinase (CK), and percentage of time standing from N calves were greater than C calves (all p ≤ 0.05). Means of percentage of time standing and CK of R calves were greater than A calves (both p ≤ 0.05). The mean of NEFA of 0 h calves was greater than the 8 h calves (p < 0.01), while the percentage of time standing of 0 h calves was less than 8 h calves (p < 0.01). Statistically significant differences between means of NEFA and standing percentage, were observed between 0 h and 8h calves. Few and inconsistent indicators of reduced welfare were observed between auction market and ranch direct calves, while non-conditioning was associated with greater physiological and behavioural indicators of reduced welfare. Based on these results, conditioning should be implemented as a management practice to improve the welfare of transported calves. [ABSTRACT FROM AUTHOR]

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Simple Summary: Lactate is a metabolite used in animal research as an indicator of muscle fatigue; therefore, it has been used as an indicator of cattle response to long distance transportation. The aim of this study was to assess the relationship of L-lactate concentrations measured using a Lactate Scout+ hand-held analyzer and a traditional lactate assay colorimetric kit. Blood samples were collected from 96 steers prior to loading and after 36 h of transportation, and prior to reloading and after an additional 4 h of road transportation, and on d 1, 2, 3, 5, 14, and 28 after transport. The Lactate Scout+ hand-held analyzer strip was dipped in blood at the time of sampling, while blood samples were collected into sodium fluoride tubes for use in the colorimetric analysis. Correlations were calculated to assess the strength of the relationship between the L-lactate concentrations measured between methods. The strength of the correlation and the level of statistical significance varied over the observed time points, while the correlation for the pooled data was weak. Based on the low strength of the correlation, the Lactate Scout+ analyzer is not a suitable alternative to a colorimetric assay for measuring L-lactate in transported cattle. Lactate is a product of anaerobic glycolysis, used in animal research as an indicator of muscle fatigue. Therefore, it has been used as an indicator of cattle response to long distance transportation. The aim of this study was to assess the relationship of L-lactate concentrations measured using a Lactate Scout+ analyzer and a traditional lactate assay colorimetric kit. Blood samples were collected by venipuncture from 96 steers (Black or Red Angus × Hereford/Simmental and Black or Red Angus × Charolais; 247 ± 38.2 kg BW) prior to loading (LO1) and after 36 h of transport, and prior to reloading and after an additional 4 h of road transportation, and on d 1, 2, 3, 5, 14, and 28 after transport. The Lactate Scout+ analyzer strip was dipped in blood at the time of sampling, while blood samples were collected into sodium fluoride tubes for use in the colorimetric analysis. Pearson correlations were calculated to assess the strength of the relationship between the experimental methods for the quantification of L-lactate concentrations. The magnitude and direction of the correlation, and the level of statistical significance varied over the observed time points, ranging from r = −0.03 (p = 0.75; LO1) to r = 0.75 (p < 0.0001; d 3). The correlation for the pooled data was weak but statistically significant (r = 0.33, p < 0.0001). Based on the low magnitude of the correlation due to variability across sampling time points in this study, the Lactate Scout+ analyzer is not a suitable alternative to a lab-based assay (considered the gold standard) for measuring L-lactate in transported cattle. [ABSTRACT FROM AUTHOR]

• Knife castrated calves experienced more acute pain than band castrated calves. • Combination of flunixin plus lidocaine reduced indicators of pain in castrated calves. • Combination of medication mitigated pain in knife and band castrated calves. One hundred and seventy-four Angus bull calves (248 ± 27.1 kg of body weight (BW), 6-mo-old) were used in a 71 d study to assess the efficacy of the combination of flunixin meglumine and lidocaine in mitigating pain associated with band and knife castration. The experiment consisted of a 3 × 2 factorial design that included castration method -sham (C), band (B) or knife (K) ; and medication – lidocaine (scrotal ring block 30 mL, 2% HCl lidocaine) and flunixin meglumine (single s.c. dose of 2.2 mg/kg BW) (M), or saline solution (NM). Animals were weighed on d 0 and weekly until d 71 (final BW) post-castration to obtain ADG. Physiological indicators included salivary cortisol collected on d 0 (30, 60, 120 and 240 min), d 2, 8, and weekly until d 48 post-castration; scrotal and eye temperature assessed on d 1, 2, 6, 8, and weekly until d 36 post-castration; fecal samples for E. coli collected on d 0, 2, 6, 8, and 22 post-castration. Behavioral measures included stride length on d 0, 8, and weekly until d 36, visual analog scale (VAS) evaluated during castration, and feeding behavior collected daily from d 0 to d 71 post-castration. Final BW and ADG were greater (P < 0.05) in C than B and K castrated calves. Salivary cortisol concentrations were greater (P < 0.05) in B and K calves than C calves up to 4-h post-castration, and remained greater in K calves up to 48-h post-castration, while concentrations were lower (P = 0.01) in M than NM calves. Fecal E. coli varied daily (P = 0.01) however, there was no obvious pattern over time. Scrotal temperature was greatest (P < 0.05) in K, intermediate in C and lowest in B calves, except at 30 min, and 22 and 36 d post-castration where they did not differ from C calves. Eye temperature was greater (P < 0.05) in B and K than C calves on d 2 and 8 post-castration. No differences (P > 0.10) were observed for stride length. The VAS scores were greater (P = 0.01) in K than C and B calves, while NM had greater scores (P < 0.01) than M calves. Dry matter intake and meal size were greater (P = 0.05) in M than NM calves. Meal duration was greater (P = 0.01) in B and C than K calves on d 0, while K calves had greater (P < 0.01) meal duration than C calves 1 and 2-wk post-castration. Overall, the combination of flunixin meglumine and lidocaine reduced physiological and behavioral indicators of pain, suggesting that their combined use was effective at mitigating pain associated with band and knife castration. [ABSTRACT FROM AUTHOR]