Veterinarians' perspectives of pain, treatment, and diagnostics for bovine respiratory disease in preweaned dairy calves

An Innovative Approach: The Usage of N-Acetylcysteine in the Therapy of Pneumonia in Neonatal Calves

NAC has mucolytic, antioxidant, and antimicrobial effects in living organisms. However, the therapeutic effects of NAC on clinical recovery among neonatal calves with respiratory diseases have not yet been studied. Our study represents the first investigation of the effects of NAC in neonatal calves with pneumonia. The objective of this work was to observe the effects of NAC in the treatment of neonatal pneumonia, including its ability to reduce the clinical score, shorten the duration of the treatment, and improve the overall health condition of neonatal calves. For this study, calves were divided into two groups: a treatment group that received NAC and amoxicillin with clavulanic acid, and a control group that received amoxicillin with clavulanic acid (antimicrobial only). The findings of this study indicate that NAC treatment significantly shortened the time to resolution (p < 0.001), compared to the results in the group without NAC treatment. Generally, NAC-supplemented therapy reduced the recovery time by more than 27 h (or slightly more than one day), compared to that in the antimicrobial-only group. Our study presents the first reported usage of NAC in therapy for respiratory disorders.

Comprehensive time-course gene expression evaluation of high-risk beef cattle to establish immunological characteristics associated with undifferentiated bovine respiratory disease

Bovine respiratory disease (BRD) remains the leading infectious disease in beef cattle production systems. Host gene expression upon facility arrival may indicate risk of BRD development and severity. However, a time-course approach would better define how BRD development influences immunological and inflammatory responses after disease occurrences. Here, we evaluated whole blood transcriptomes of high-risk beef cattle at three time points to elucidate BRD-associated host response. Sequenced jugular whole blood mRNA from 36 cattle (2015: n = 9; 2017: n = 27) across three time points (n = 100 samples; days [D]0, D28, and D63) were processed through ARS-UCD1.2 reference-guided assembly (HISAT2/Stringtie2). Samples were categorized into BRD-severity cohorts (Healthy, n = 14; Treated 1, n = 11; Treated 2+, n = 11) via frequency of antimicrobial clinical treatment. Assessment of gene expression patterns over time within each BRD cohort was modeled through an autoregressive hidden Markov model (EBSeq-HMM; posterior probability ≥ 0.5, FDR < 0.01). Mixed-effects negative binomial models (glmmSeq; FDR < 0.05) and edgeR (FDR < 0.10) identified differentially expressed genes between and across cohorts overtime. A total of 2,580, 2,216, and 2,381 genes were dynamically expressed across time in Healthy, Treated 1, and Treated 2+ cattle, respectively. Genes involved in the production of specialized resolving mediators (SPMs) decreased at D28 and then increased by D63 across all three cohorts. Accordingly, SPM production and alternative complement were differentially expressed between Healthy and Treated 2+ at D0, but not statistically different between the three groups by D63. Magnitude, but not directionality, of gene expression related to SPM production, alternative complement, and innate immune response signified Healthy and Treated 2+ cattle. Differences in gene expression at D63 across the three groups were related to oxygen binding and carrier activity, natural killer cell-mediated cytotoxicity, cathelicidin production, and neutrophil degranulation, possibly indicating prolonged airway pathology and inflammation weeks after clinical treatment for BRD. These findings indicate genomic mechanisms indicative of BRD development and severity over time.

Pain Assessment in Cattle by Use of Numerical Rating and Visual Analogue Scales-A Systematic Review and Meta-Analysis

Subjective pain assessment in cattle is contingent upon the observer's experience and attitude. Studies of pain assessment in cattle by veterinarians and farmers using different pain scales have been published. This systematic review and meta-analysis aimed to describe and compare the pain scores given by veterinarians and producers for different procedures and conditions using either a NRS or VAS. The literature search was conducted with PubMed (MEDLINE) and Agricola, using defined search terms (e.g., peer-reviewed). A total of 842 articles were identified. After screening of duplicates, abstracts, and full texts, a total of 16 articles were included in this systematic review. Different pain scales were used for the included studies (NRS 0-10 for eight studies, NRS 1-10 for six studies, NRS 1-10 and VAS 0-10 for one study, and VAS 0-1 for one study). Most studies (n = 11) originated from the European Union. Mean values for pain scores differed significantly between studies included in the meta-analysis for both NRS 0-10 and 1-10. The findings of this study indicated that comparison of pain scoring used in different studies is difficult due to use of different pain scales and varying nomenclature, and that many variables (such as age and gender) influence pain scoring.