Comparison of virus-neutralizing and virus-specific ELISA antibody responses among bovine neonates differentially primed and boosted against bovine coronavirus

Objective

This study addressed the current gap in knowledge of neonatal prime-boost immune responses for the control of bovine coronavirus (BCoV) respiratory disease in weaning-age beef cattle.

Animals

Study 1 and Study 2 had 33 and 22 commercial cross neonatal beef calves, respectively.

Procedures

Study 1 compared BCoV-neutralizing antibody concentrations of control calves with 3 groups of calves differentially vaccinated with mucosal and/or systemic BCoV modified live virus (MLV) vaccines. Study 2 compared specific and neutralizing antibody concentrations among mucosally BCoV primed groups of calves that were differentially systemically boosted.

Results

In Study 1, calves that were mucosally primed and systemically boosted had higher BCoV-neutralizing antibody concentrations than the control group at weaning. In Study 2, boosting mucosally primed calves by injecting inactivated or MLV vaccine resulted in anamnestic BCoV-specific antibody responses at weaning.

Conclusion

Neonatal mucosal priming and systemic boosting resulted in anamnestic BCoV antibody responses at weaning.

Clinical relevance

Prime-boost vaccination should be considered for control of BCoV respiratory disease.

Ergonomic assessment of veterinarians during performance of bovine reproductive examinations

OBJECTIVE

To identify and quantify potential ergonomic hazards associated with routine reproductive examinations of cattle.

SAMPLE

7 bovine veterinarians.

PROCEDURES

Each veterinarian was observed and videotaped during 2 bovine reproductive examination appointments. During each appointment, a force-matching protocol was used to estimate the entry force used by the veterinarian to insert an arm into a cow's rectum. Veterinarian posture and repetitive movements and the work environment were assessed and quantified during review of the video recordings. Descriptive data were generated.

RESULTS

Of the 14 appointments observed, 9 and 5 involved examination of beef and dairy cows, respectively. For all veterinarians, an arm inclination ≥ 60° was observed during most reproductive examinations. The number of examinations performed per hour ranged from 19.1 to 116.8. The estimated entry force ranged from 121 to 349 N. During all 9 appointments involving beef cows, the veterinarian participated in other tasks (eg, operating overhead levers, opening gates, or assisting with cattle handling) that represented ergonomic hazards.

CONCLUSIONS AND CLINICAL RELEVANCE

Results confirmed that reproductive examination of cattle exposes veterinarians to various ergonomic hazards involving awkward positions and repetitive and forceful exertions that can contribute to musculoskeletal discomfort and injury, particularly of the upper extremities (neck, shoulders, upper back, arms, elbows, wrists, and hands). Veterinarians frequently participated in other tasks during reproductive examination appointments that exposed them to additional ergonomic hazards. Risk mitigation strategies should prioritize minimizing exposure of veterinarians to tasks not directly associated with the reproductive examination procedure to decrease their overall ergonomic hazard burden.

Risk factors associated with work-preventing musculoskeletal discomfort in the upper extremities of bovine practitioners

OBJECTIVE

To identify risk factors associated with work-preventing musculoskeletal discomfort (MSKD) in the upper extremities (defined as neck, shoulders, upper back, arms, elbows, wrists, and hands) of bovine practitioners.

SAMPLE

116 members of the Western Canadian Association of Bovine Practitioners.

PROCEDURES

Data from a previously described cross-sectional survey of western Canadian bovine practitioners underwent further analysis. The survey, developed to glean information about MSKD in bovine practitioners, was a modified standardized Nordic questionnaire that included questions regarding personal and work characteristics and incidence and location of MSKD during the preceding 12 months along with perceptions about most physically demanding tasks. Logistic regression was used to identify factors associated with work-preventing upper extremity MSKD.

RESULTS

18 of 116 (15.5%) respondents indicated they had experienced work-preventing upper extremity MSKD during the preceding 12 months. The final multivariable regression model indicated that practice type (mixed animal vs primarily [> 50%] bovine; OR, 3.20; 95% CI, 0.96 to 10.67), practitioner height (OR, 0.93; 95% CI, 0.87 to 0.99), and number of veterinarians in the practice (OR, 1.32; 95% CI, 1.05 to 1.66) were significantly associated with the odds of work-preventing upper extremity MSKD.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggested that reproductive examination of cattle was not a significant risk factor for upper extremity MSKD in bovine practitioners. Further research into the effects of biomechanical, organizational, and psychosocial workplace factors on the development of MSKD in bovine practitioners is necessary to help inform prevention strategies to foster career longevity in this increasingly diverse practitioner group.

Evaluation of bovine respiratory syncytial virus (BRSV) and bovine herpesvirus (BHV) specific antibody responses between heterologous and homologous prime-boost vaccinated western Canadian beef calves

Bovine respiratory disease (BRD) is an economically important cause of morbidity and mortality in beef calves. Control of BRD is most often addressed through "homologous" vaccination utilizing the same injectable modified-live viral (MLV) vaccine for both priming and boosting. Heterologous prime-boosting uses different routes and antigenic forms for priming and boosting. Three vaccine protocols were compared: an injectable (IJ) MLV (IJ-MLV) group (IJ-MLV priming at ~48 days and boosted with IJ-MLV at weaning), intranasal (IN) MLV (IN-MLV) group (intranasal priming with MLV at ~24 hours, boosted twice with an IJ-MLV), and intranasal killed viral (IN-KV) group (primed with an IN-MLV at ~24 hours, boosted twice with an IJ-KV). Serum antibody concentrations determined by enzyme-linked immunosorbent assays (ELISAs) were compared and the IN-KV group had significantly higher BRSV-specific antibody concentrations after boosting compared with the 2 homologous groups. No differences in BHV-specific antibody concentrations were observed between any of the groups.