A survey of practices and attitudes around cull cow management by bovine veterinarians in Ontario, Canada.

The removal (culling) of dairy cows from the farm is a regular and required management practice. The main objectives of this study were to describe the involvement of bovine veterinarians in Ontario, Canada, in dairy cull cow management decisions, their expectations of current producer practices, and their perspectives on welfare issues and best management practices for cull dairy cows. Between February and May 2021, a province-wide survey was conducted among all members of the Ontario Association of Bovine Practitioners (OABP), with questions addressing veterinarians' background and demographics, veterinary clinic characteristics, cull cow management, down cow management, and learning preferences. The response rate for the survey was 25.1%, with 45 responses meeting all eligibility criteria. Dairy veterinarians would like to have greater involvement in cull cow management; when asked for desired involvement in culling decisions, 57.5% of veterinarians would like to be involved in culling decisions most of the time or always. Most (70.0%) veterinarians believed that cull cow welfare has improved over the last decade. However, most respondents also identified at least one area of management (farm of origin, transportation, auction, slaughter) as currently being a high risk to cull cow welfare. Given the frequency of their visits, trust by dairy producers, and knowledge, herd veterinarians are among those in the best position to improve the care of cull dairy cows. Information generated from this survey can be used to inform the development of improved decision-making tools for culling cows, and this, along with increased veterinarians' involvement in cull cow management, could improve the economic and welfare outcomes of culling decisions for dairy producers.

Effect of stall design on dairy calf transition to voluntary feeding on an automatic milk feeder after introduction to group housing.

Automatic milk feeders (AMF) for young dairy calves are widely used in the dairy industry. These feeders are thought to have benefits for calf health and welfare and may reduce labor required for feeding; however, little is known about how calves adapt to feeding with AMF. The objective of this study was to observe the effects of feeding stall design on calves learning to use the AMF. The hypothesis was that solid side stalls, compared with steel bar stalls, would result in a longer latency to approach and feed from the AMF without assistance. A total of 147 Holstein calves (80 male and 67 female) were enrolled at 4 d of age, introduced to a group pen, and, at the same time, trained on an AMF. For training, calves were allowed to suck on the trainer's fingers and guided to the teat. Calves were allocated to 1 of 2 stall designs at the pen level, depending on which treatment cohort they were born into, either with steel bar stall walls (n = 46 male, 34 female calves) or with solid side stall walls (n = 34 male, 33 female calves). For 72 h after introductory training on the AMF, data from the feeders were collected and calf behavior was monitored by video. Outcomes measured included latency to first voluntary visit to the feeder and to first feeding, time spent in the feeder, amount of milk consumed over 72 h, number of retraining sessions required (retrained if <2 L was consumed every 12 h), and exploratory behavior, such as sniffing and licking of the feeder. Data were analyzed using mixed effects linear regression models or a Poisson model for the outcome of retraining. For certain outcomes the effects of stall design interacted with difficulty of training (willingness to enter feeder and drink); for the 38% of calves that were scored as moderately difficult to train on a scale of easy, moderate, or difficult, treatment (stall design) differences were detected. These calves took 2× longer to lick or bite toward the nipple, 2× longer to first voluntarily feeding, and consumed less milk over 72 h following training when trained on the steel bar stall design. These results suggest simple features of a stall may influence how quickly calves learn to use an AMF, but that the influence of stall wall design was affected by how easy calves were to train on the feeder upon initial introduction, which may depend in part on certain aspects of calf temperament. For many calves, solid side stalls at an AMF resulted faster in adaption than the steel bar stalls.

Associations between the general condition of culled dairy cows and selling price at Ontario auction markets.

Dairy cows are culled from the herd for a variety of reasons, the most common being fertility problems, low milk production, or udder problems. Disease and injury can contribute to the decision to cull either directly, or indirectly, by causing fertility or production problems, leading to culling. Disease or injury may also affect the cow's ability to handle the stress of transportation and may increase the risk for reduced welfare. The purpose of this study was to determine the general condition of culled dairy cows sold at Ontario auction markets, to quantify the frequency of culled cows in poor condition sold at these auctions, and to determine how this relates to the sale price of the cow. Data were collected on 4,460 culled dairy cows, sold at 3 Ontario auction markets, over a continuous 16-wk study period. Observers assessed the general condition of dairy cows entering the sales ring by recording each individual cow's hock injury score, body condition score (BCS), gait score, and tail score, in accordance with 2017 Canadian proAction Animal Care guidelines. Each cow's body weight, breed, and sale price were also recorded. Results showed that 27.2% of culled cows scored had unacceptable hock injuries, 40.5% had a BCS ≤2, 72.7% had an abnormal gait, and 12.5% had docked tails. Culled cows with a BCS ≤2 sold for $0.20 less/kg compared with those with a BCS >2, which equated to an overall average loss of $117 per cow. Cows with an abnormal gait sold for $0.05 less/kg compared with culled cows with a normal gait, which equated to an overall average loss of $32.45 per cow. There was no difference in the sale price depending on hock injury score or the presence or absence of a full tail. The main issues identified in this study were the high prevalence of low body condition and abnormal gait, indicating that the welfare of these cows may be at risk. Additionally, cows with low BCS or abnormal gait sold for a lower price compared with cows that were in good condition, leading to reduced potential profit for the producer.

Comparison of online, hands-on, and a combined approach for teaching cautery disbudding technique to dairy producers.

The use of pain control for disbudding and dehorning is important from both an animal and industry perspective. Best practices include the use of local anesthetic, commonly given as a cornual nerve block (CNB), and a nonsteroidal anti-inflammatory drug. The proportion is decreasing, but many dairy producers do not use local anesthesia, perhaps in part due to lack of knowledge of the CNB technique. Although this skill is typically learned in person from a veterinarian, alternative methods may be useful. The objective of this trial was to determine if there were differences in the efficacy of online training (n = 23), hands-on training (n = 20), and a combined approach (n = 23) for teaching producers to successfully administer a CNB and disbud a calf. The primary outcome was block efficacy, defined as a lack of established pain behaviors during iron application. Secondary outcomes were background knowledge (assessed by a written quiz), CNB and disbudding technique (evaluated by rubric scoring), time taken, and self-confidence before and after evaluation. Associations between training group and outcome were assessed with logistic regression, ordered logistic regression, and Cox-proportional hazard models, with a random effect for workshop. Block efficacy was not different between training groups, with 91% successful in both combined and online groups, and 75% in the hands-on trained group. Online learners had poorer technical scores than hands-on trainees. The combined group was not different from hands-on. Time to block completion tended to be longer for the online group (62 ± 11 s), whereas time to disbudding completion was not different between hands-on (41 ± 5 s) or combined trainees (41 ± 5 s). The combined group had the highest pre-evaluation confidence score, and remained higher after evaluation than online but was not different than hands-on. Although we saw some statistical differences between groups, absolute differences were small and block efficacy was similar. This suggests online training can be a useful tool for motivated producers who lack access to hands-on training.

Effects of local anesthetic or systemic analgesia on pain associated with cautery disbudding in calves: A systematic review and meta-analysis.

Disbudding is a common management procedure performed on dairy farms and, when done without pain mitigation, is viewed as a key welfare issue. Use of pain control has increased in recent years, but full adoption of anesthesia and analgesia by veterinarians or dairy producers has not been achieved. This may in part be due to the lack of a consistent recommendations of treatment protocols between studies examining pain control methods for disbudding. The objective of this systematic review was to examine the effects of these pain control practices for the most common method of disbudding, cautery, on outcomes associated with disbudding pain in calves. The outcomes were plasma cortisol concentrations, pressure sensitivity of the horn bud area, and validated pain behaviors (ear flick, head shake, head rub, foot stamp, and vocalization). Intervention studies describing cautery disbudding in calves 12 wk of age or younger were eligible, provided they compared local anesthesia, nonsteroidal anti-inflammatory drug (NSAID), or local anesthesia and NSAID to 1 or more of local anesthesia, NSAID, or no pain control. The search strategy used the Agricola, Medline (via OvidSP), and Web of Science databases, as well as the Searchable Proceedings of Animal Conferences (S-PAC), ProQuest Dissertations and Theses Database, and Open Access Theses and Dissertations. Meta-analysis was performed for all outcomes measured at similar time points with more than 2 studies. Local anesthetic was associated with reduced plasma cortisol until 2 h postdisbudding; however, a rise in cortisol was observed in the meta-analysis of studies reporting at 4 h postdisbudding. Heterogeneity was present in several of the analyses for this comparison. The addition of NSAID to local anesthetic showed reduction in plasma cortisol at 4 h, and a reduction in pressure sensitivity and pain behaviors in some analyses between 3 and 6 h postdisbudding. Heterogeneity was present in some meta-analyses, including several using pain behavior outcomes. This may reflect the variation in measurement time periods for behavioral measures between studies, as well as differences among NSAID treatments. Overall, a protective effect of local anesthetic was seen for the acute pain of cautery disbudding, and the delayed rise in cortisol was mitigated by the addition of an NSAID, which also reduced other signs of pain, including pressure sensitivity and pain behaviors. Based on these findings, we recommend use of local anesthetic and an NSAID as best practices for pain mitigation for cautery disbudding of calves 12 wk of age or less. The magnitude and duration of the effect of NSAID treatment was not possible to deduce from the literature because wide variation existed between studies. We recommend consideration of more standardized outcome measurements, especially for pain behaviors. Adherence to reporting guidelines by authors would help ensure more transparent and complete information is available to end users.

Effect of age of introduction to an automated milk feeder on calf learning and performance and labor requirements.

Group housing of dairy calves with automated milk feeders (AMF) is increasingly being used, but the effect of introducing calves to the AMF at a very young age (<24 h) on calf performance, health, and welfare, as well as farm personnel labor requirements are unknown. The objective of this controlled trial was to investigate whether early (<24 h after birth) introduction of calves affects the time to learn how to drink from the AMF, labor requirements for feeding milk during the learning phase, and average daily gain during the milk-feeding period compared with calves conventionally introduced at 5 d of age. Sixty Holstein calves (heifers and bulls) were assigned at birth to either early introduction (<24 h after birth) or conventional introduction (at 5 d of age) to the group pen with AMF. After birth, calves were housed in individual pens and then introduced, based on assigned treatment, to the group pen with an AMF and a continuous flow stocking approach. Calves were fed milk replacer and gradually weaned from d 47 to 60 of age. Calves had access to starter from 5 d of age, and to water and straw right after colostrum feeding. We measured the time between first training to use the AMF and first unassisted visit to the AMF with milk intake, the number of assisted visits until the calf was independent in its use of the AMF (successful learning), and the total time required for milk feeding (labor) until successful learning. Calves were weighed at birth, 30, 46, and 61 d of age, and were monitored daily for signs of disease. Daily milk and starter intake per calf were automatically recorded. Early-introduced calves took longer to successfully learn to use the AMF {64.9 h [95% confidence interval (CI) = 59.1 to 77.9] vs. 31.4 h (95% CI = 22.8 to 47.9)} and tended to require more assisted visits [7.8 visits (95% CI = 6.2 to 9.7) vs. 5.9 visits (95% CI = 4.8 to 7.5)] compared with conventionally introduced calves. Labor for milk feeding was greater for conventionally introduced calves relative to early-introduced calves [145.6 min (95% CI = 125.1 to 169.4) vs. 39.9 min (95% CI= 33.5 to 47.6)]. Disease risk was similar between treatments but the risk of severe versus mild diarrhea was greater for early- compared with conventionally introduced calves (odds ratio = 4.7; 95% CI 1.01 to 31.1). Early-introduced calves consumed less milk during the first days of life compared with conventionally introduced calves (d 2 = 5.5 vs. 6.4 L; d 3 = 7.0 vs. 8.2 L; d 4 = 7.0 vs. 8.4 L; d 6 = 6.4 vs. 7.9 L; d 7 = 6.0 vs. 7.0 L, respectively), with no differences after 8 d. We found no effect of treatment on average daily gain. Although introducing calves <24 h after birth required more assistance to use the AMF, farm labor for milk feeding tasks was less for early-introduced calves. Thus, with early introduction to AMF, a trade-off may exist between reduced labor per calf, with no effect on weight gain, but potentially a higher risk of severe diarrhea (vs. mild).

Associations between management practices and within-pen prevalence of calf diarrhea and respiratory disease on dairy farms using automated milk feeders.

Data on management practices used with automated milk feeders (AMF) are needed to identify factors associated with calf health in these systems. The objectives of this observational, longitudinal, cross-sectional study were to estimate the prevalence of calf diarrhea (CD) and bovine respiratory disease (BRD), and to identify factors associated with prevalence of these diseases at the pen level on dairy farms feeding milk to group-housed calves with AMF. Seventeen dairy farms with AMF in Ontario, Canada, were visited 4 times, seasonally, over 1 yr. The clinical health of all calves (n = 1,488) in pens (n = 35) with AMF was scored to identify the number of calves with CD and BRD. Data on calf, feeder, and pen management practices were analyzed using generalized linear mixed regression models for each disease. Overall calf-level prevalence of CD and BRD were 23 and 17%, respectively. Median (interquartile range, IQR) within-pen prevalence of CD and BRD were 17% (7 to 37%) and 11% (0 to 28%), respectively. Median age (IQR) for diarrheic calves was 25 d (16 to 42 d), and for calves with BRD was 43 d (29 to 60 d). Factors associated with lower within-pen prevalence of CD were the administration of vitamin E and selenium at birth [odds ratio (OR) = 0.56; 95% confidence interval (CI): 0.32 to 0.99], feeding of probiotics (OR = 0.44, 95% CI: 0.22 to 0.93), and adding fresh bedding every 2 to 3 d (OR = 0.43; 95% CI: 0.24 to 0.76) compared with every 7 or more days. In contrast, sharing air with older cattle (>9 mo old) was associated with increased within-pen prevalence of CD (OR = 4.54, 95% CI: 1.88 to 10.52). Additionally, total bacteria counts ≥100,000 cfu/mL in milk samples taken from the AMF mixing jar were associated with increased within-pen prevalence of CD during the summer visit (OR = 3.34; 95% CI: 1.31 to 8.54). Increased total solids in milk or milk replacer (OR = 0.48, 95% CI: 0.27 to 0.85) and feeding whole milk versus milk replacer (OR = 0.29, 95% CI: 0.11 to 0.75) were associated with lower within-pen prevalence of BRD. Factors associated with greater within-pen prevalence of BRD were sharing air with weaned cattle up to 8 mo old (OR = 3.21, 95% CI: 1.26 to 8.16), and greater depth of the wet bedding pack. The use of maternity pens for reasons other than just calving was associated with increased prevalence of both CD and BRD (OR = 1.85, 95% CI: 1.03 to 3.33; OR = 2.61, 95% CI: 1.21 to 5.58, respectively). These results suggest that isolation from older animals and frequent cleaning of the feeder and pen may help to reduce disease prevalence in group-housed calves fed with an AMF.

Clinical trial of local anesthetic protocols for acute pain associated with caustic paste disbudding in dairy calves.

Caustic paste disbudding is becoming more commonplace in North America. A large body of work has examined pain control for cautery disbudding and surgical dehorning, but fewer studies have evaluated pain control for caustic paste disbudding, and results conflict regarding benefits of local anesthesia. In humans, the pain associated with a caustic, chemical burn can differ in nature, duration, and intensity compared with a thermal burn. The objective of this clinical trial was to evaluate the effects of either a lidocaine cornual nerve block or a topical anesthetic incorporated into caustic paste on the acute pain of caustic paste disbudding. Seventy-two Holstein-Friesian calves housed in groups with an automated milk feeder were enrolled into 18 replicates balanced on age and assigned to 1 of 4 treatments: sham (S), placebo paste and a saline cornual block; topical (T), a novel caustic paste containing lidocaine and prilocaine, and a saline cornual block; cornual block (B), commercial caustic paste and a lidocaine cornual nerve block; and positive (P), commercial caustic paste and a saline cornual block. All calves received 0.5 mg/kg of meloxicam SC at the time of the block. Researchers were blinded to treatment group. Primary outcomes were validated pain behavior responses and pain sensitivity measured by algometry. Secondary outcomes consisted of respiratory and heart rate, latency to approach the evaluator, play behavior, feeding behavior, and standing and lying bout characteristics. Data were analyzed using linear, Poisson, and negative binomial regression models. Cornual-blocked calves had less pain sensitivity to 180 min after disbudding than all other groups; T and P calves had more pain sensitivity than S calves for the same time period. Compared with T and P calves, B and S calves had fewer pain behaviors until 120 min postdisbudding, decreased respiratory and heart rates, and a shorter latency to feed. The S calves exhibited more play behavior than other groups. Caustic paste appears to be acutely painful for at least 180 min, and this is reduced by a cornual nerve block but not by our novel paste. Because caustic paste may result in a different pain experience than cautery, use of a variety of metrics assessing affective state, physiologic responses, and normal behaviors, such as feeding and lying, should be included into future trials to help assess the welfare of calves disbudded by this method. We recommend that calves disbudded with caustic paste receive local anesthetic with a cornual nerve block as well as a nonsteroidal anti-inflammatory drug to mitigate acute pain.

A survey of dairy calf management practices among farms using manual and automated milk feeding systems in Canada.

Dairy calves in North America traditionally are housed individually and fed by manual milk feeding (MMF) systems with buckets or bottles. Automated milk feeders (AMF) allow for more natural milk feeding frequencies and volumes, and calves are usually housed in groups. The objectives of this study were to (1) determine the prevalence of various milk-fed calf management and feeding practices and (2) compare these practices between dairy farms using MMF and AMF systems. A national online survey was performed from January to May 2015 to quantify management practices for the care of milk-fed dairy calves in Canada. A total of 670 responses were received (6% of all dairy farms in Canada). Among respondents, 16% used AMF and 84% used MMF. Seventy percent of the farms using AMF had freestall barns compared with only 48% of those using MMF. A greater proportion of AMF farms (30%) also had automatic milking systems (AMS) compared with MMF farms (8%). Among tiestall farms, a herd size of >80 milking cows was associated with having an AMF [odds ratio (OR) = 3.8; 95% confidence interval (CI): 1.6-11.4]. For freestall or bedded-pack farms, a herd size of >80 milking cows (OR = 3.5; CI: 1.8-6.6), having an AMS (OR = 3.1; CI: 1.6-5.7), and use of cow brushes (OR = 3.1; CI: 1.3-6.9) were associated with having an AMF. Calves fed with AMS typically were housed in groups of 10 to 15, whereas almost 76% of the farms with MMF housed calves individually. Although both AMF and MMF farms fed similar amounts of milk in the first week of life (median = 6 L/d), the cumulative volume fed in the first 4 wk differed significantly, with a median of 231 versus 182 L for AMF and MMF, respectively. Median peak milk allowance was higher for AMF than for MMF (10 vs. 8 L/d, respectively). In summary, farms using AMF were larger, provided more milk to calves, and used more automation in general (i.e., in other areas of their operation). These data provide insights into calf-rearing practices across Canada and into how the use of AMF is affecting calf feeding and management on dairy farms.

Comparison of an online learning module to hands-on training in teaching a cautery disbudding technique for dairy calves including cornual nerve block application.

Disbudding and dehorning are common procedures on dairy farms. In a recent survey of Ontario dairy producers, 38% reported not using local anesthetic for these procedures. Use of pain control is important for both calf welfare and industry sustainability. Use of local anesthetic requires technical training, typically provided by a veterinarian, although online training videos also exist. Neither method has been studied for efficacy. Our objective was to compare an online module to hands-on training in teaching naïve participants (veterinary students) to effectively carry out a cornual nerve block and disbud a dairy calf. Participants were assigned to either an online or hands-on training group. Although no statistical differences were seen in success of the nerve block, online learners were less confident and had poorer technical skills. While online learning was surprisingly effective for a psycho-motor skill, best practices should include hands-on training.

Comparaison d'un module d'apprentissage en ligne avec une formation pratique pour l'enseignement de la technique d'enlèvement des bourgeons par cautérisation pour les vaches laitières incluant l'application d'un bloc du nerf de la corne. L'enlèvement des bourgeons et l'écornage sont des interventions fréquentes dans les fermes laitières. Dans une étude récente auprès des producteurs laitiers de l'Ontario, 38 % ont signalé ne pas utiliser d'anesthésie locale pour ces interventions. Le recours au contrôle de la douleur est important pour le bien-être du veau et la durabilité de l'industrie. L'utilisation de l'anesthésie locale exige une formation technique, qui est habituellement fournie par un médecin vétérinaire, quoique des vidéos de formation en ligne existent également. Ni l'une ni l'autre des méthodes d'enseignement n'a été étudiée pour en évaluer l'efficacité. Notre objectif consistait à comparer le module en ligne à une formation pratique pour l'enseignement des participants non initiés (étudiants en médecine vétérinaire) afin de réaliser efficacement un bloc du nerf de la corne et d'enlever le bourgeon chez un veau laitier. Les participants ont été assignés au hasard à un groupe de traitement. Même si aucune différence statistique n'a été observée pour le succès du bloc nerveux, les apprenants en ligne manifestaient moins de confiance et avaient des compétences techniques inférieures. Même si l'apprentissage en ligne était étonnamment efficace pour une compétence psychomotrice, les meilleures pratiques devraient inclure une formation pratique.(Traduit par Isabelle Vallières).

Practices for the disbudding and dehorning of dairy calves by veterinarians and dairy producers in Ontario, Canada.

Disbudding and dehorning dairy calves is very common, despite the introduction of polled genetics to most dairy breeds. Appropriate pain-control practices for these procedures affect both calf welfare and public perception of the dairy industry. Previously published work has shown that North American dairy producers have not widely adopted use of these medications for disbudding or dehorning. However, since the last published work examining these practices in Canada, changes regarding awareness, availability, and future requirements for pain control have occurred in the industry. With this in mind, online and telephone surveys of both veterinarians (n=238) and dairy producers (n=603) in Ontario, Canada, were conducted in the fall of 2014 with a goal of describing current disbudding and dehorning practices and examining factors associated with the adoption of pain control use. Approximately three-quarters of dairy producers reported performing disbudding or dehorning themselves, whereas the remainder used a veterinarian or technician. Almost all (97%) of the veterinarians surveyed reported using local anesthetic, 62% used sedation, and 48% used a nonsteroidal anti-inflammatory drug. Producer use of local anesthetic was 62%, 38% used sedation and 24% used a nonsteroidal anti-inflammatory drug. Seventy-eight percent of veterinarian disbudding or dehorning was done before 8wk of age, whereas 64% of dairy producers performed this procedure before 8wk of age. Seventy-two percent of veterinarians and 63% of producers reported changing their disbudding or dehorning practices over the past 10 yr; of producers that changed their practices, 73% cited their herd veterinarian as influential. The use of pain control described in these surveys is higher than previously reported in Ontario. Identification of factors associated with best practices, or the lack of adoption of these practices, may help veterinarians target appropriate educational opportunities for their dairy clients.

Technical note: a comparison of 2 methods of assessing lameness prevalence in tiestall herds.

We compared 2 methods for identifying lame cows and estimating the prevalence of lameness in tiestalls. Cows (n=320) in 9 tiestall herds were scored as lame both by the presence of limping while walking and by stall lameness scores (SLS). The SLS was based on the number of the following behaviors that the cow showed while standing in the tiestall: weight shifting, standing on the edge of the stall, uneven weight bearing while standing, and uneven weight bearing while moving from side to side. Two observers watched video-recordings of the cows. Intraobserver agreements for the 4 SLS behaviors ranged from 92 to 100%, and interobserver agreement ranged from 81 to 100%. The overall prevalence of lameness based on an SLS of ≥2 was similar to that of limping (39 vs. 40%). The sensitivity of the classification based on the SLS was 0.63 and the specificity was 0.77 in identifying cows with a limp; accuracy varied across farms from 62.2 to 80.4%, with a mean of 71.7%. A cow with an SLS of ≥2 had 4.88 times the odds of limping than a cow with an SLS of <2. The prevalence of lameness on farms based on SLS was highly correlated with the prevalence of limping (Pearson correlation=0.88; n=9), and prevalence estimates from the 2 methods diverged most when the mean herd prevalence was lower. The SLS method provides an estimate of the prevalence of lameness in tiestall herds comparable with traditional gait scoring, but does not require that the cows be untied. The SLS method could be used to improve lameness detection on tiestall farms and obtain estimates of lameness prevalence without the need to walk the cows.

Perceived role of the veterinarian in promoting dairy cattle welfare.

Improving the lives of animals in agricultural systems has primarily focused on minimizing negative experiences. Research is needed on the promotion of positive experiences (pleasure, enjoyment, play, choice, happiness) for animals and the role of veterinarians in their promotion. Our aims were to describe how Canadian bovine veterinarians and veterinary students perceive the role of a veterinarian in positive vs. negative experiences for dairy cows and to analyze the rationale provided to explain their answers. Canadian veterinary practitioners (n = 78) and veterinary students (n = 148) responded to an online cross-sectional survey and were asked, on a 7-point scale, how important the role of a veterinarian is to promote practices that influence the experience of dairy cows. We used qualitative description to analyse participants' open-ended text responses. Practices to minimize negative experiences were most important (mean ± SE; 6.8 ± 0.03), a balance of positive and negative experiences was less important (6.4 ± 0.05), and encouragement of positive experiences scored lowest (6.0 ± 0.06), although all scored highly. Four themes were identified to explain participants' reasoning regarding their perceived role of a veterinarian in the promotion of dairy cattle welfare, centered on: the animal, the producer, the veterinarian, and society. Participants indicated that promoting positive experiences was less important than decreasing negative experiences (5.9 ± 0.09). There were four themes identified to explain participants' reasoning regarding the relative importance of promotion of positive experiences versus decreasing negative experiences which centered on: frameworks to compare positive and negative experiences, impacts on the animal, the participant's view of their role, and the practicality of implementation. These results indicate modest differences in valuing avoidance of negative vs. promotion of positive welfare. There were no differences in the quantitative analyses between veterinarians and veterinary students. We conclude that veterinarians are favorably disposed to positive aspects of welfare for dairy cows but may be more focussed on avoidance of negative aspects of welfare.

A focus group study exploring dairy farmers' perspectives of cull cow management in Ontario, Canada.

Introduction: Maintaining the welfare of cull dairy cows from the farm to slaughter is an ongoing challenge for the dairy industry. Recent research suggests that some cull dairy cows within the marketing system are in physical states that are below regulatory standards, and further research is required to determine why these unfit cows are found throughout the journey to abattoirs. Since dairy farms are the origin of these cows, decision making by dairy farmers has been identified as key to preventing cull cows that are considered unfit for transport from entering the marketing system. The objectives of this study were to understand dairy farmers' perspectives on their cull dairy cow management practices, recommendations and requirements of regulations, management tools, and welfare issues. Methods: Four focus groups with a total of 21 participants were each conducted virtually, video recorded, and transcribed verbatim, with dairy farmers from Ontario, Canada. A thematic analysis of focus group discussions was conducted utilizing deductive reasoning. Results: There were three themes identified including deciding to cull or not, management of cows being culled, and knowledge and perceptions of cull cow regulations. When making culling decisions, farmers utilize multiple sources of information including personal experiences and values and external referents like veterinarians, family members and other farmers. The welfare of their cows was a high priority but one that was often weighed against the financial outcomes of culling decisions. Finally, most participants considered recent regulatory changes for the management of cows before shipment to be of little importance on their farms. Discussion: In conclusion, the farmers from this study showed the diversity of considerations they make in culling decisions and the large contribution of animal productivity and economic factors. There was a general lack of knowledge of recent regulatory changes for the shipment of cull cows, and there is room for improving the uptake of new recommendations for culling only cows fit for transportation.

Onset, duration and efficacy of four methods of local anesthesia of the horn bud in calves.

OBJECTIVE: To determine the onset, duration and efficacy of four local anesthetic methods for the horn bud in calves. STUDY DESIGN: Crossover study. ANIMALS: Eight, 2 month-old Holstein Friesian bull calves. METHODS: Calves were subjected to one of the four following treatments: 1) cornual nerve block (C), 2) ring block (R), 3) cornual nerve block using a percutaneous jet delivery technique (JET) all using 2% lidocaine with epinephrine (0.01 mg mL(-1)), and 4) topical eutectic mixture of local anesthetics (EMLA) cream. A peripheral nerve stimulator was used to assess cutaneous sensation over the horn bud using a graded response. Onset, duration and efficacy of anesthesia were determined. RESULTS: The efficacy of the blocks was as follows: C 87.5%, R 100%, JET 37.5%, EMLA 0%. The median onset time and duration of anesthesia for C and R were: 2 (range 0.5-5) and 304 (range 107-512), and 3.25 (range 1-9) and 147 (range 62-299) minutes, respectively. Three of eight JET injections had a median onset and duration of 8 (range 0.5-9) and 132 (range 101-155) minutes, respectively. The duration of the C block was significantly longer than the R block (p = 0.047). CONCLUSIONS AND CLINICAL RELEVANCE: The relatively rapid onset and long duration of anesthesia with C or R blocks using 2% lidocaine with epinephrine validates their practical use in dehorning calves while jet injection and EMLA cream provided insufficient analgesia to be clinically useful. The efficacy of the C block requires further study.

The protective role of wallowing against heat stress in gestating and lactating sows housed outdoors.

The objective of this study was to describe the physiological response of gestating and lactating sows to naturally-occurring environmental conditions, and to identify factors that may contribute to or prevent heat stress, while being kept outdoors in Québec, Canada during the summer. Six groups of 4 Yorkshire-Landrace sows lived in outdoor pens equipped with a wallow, shade structure, farrowing huts and access to a pasture from July to September 2018. Between week 15 of gestation and week 3 of lactation (inclusive), we recorded the location of each sow 5 days/week during 5 daily 15-min observation periods, and additionally measured the sow's respiratory rate and mud cover at the end of each observation period. Simultaneously, we collected sow body temperature data with vaginal temperature loggers 24 h/d on week 15 of gestation and week 2 of lactation, and monitored environmental conditions with temperature and humidity loggers to calculate the temperature humidity index (THI). Sows had significantly higher and more variable body temperatures during lactation compared to gestation (P ≤ 0.0001), and when THI was analysed as a continuous variable, it was positively associated with sow body temperature during the night in lactation. During gestation, neither respiratory rate nor body temperature were associated with high or low levels of THI (P = 0.15 and 0.79, respectively) or mud cover (P = 0.29 and 0.94, respectively). However, in lactation, respiratory rate was higher when, simultaneously, THI exceeded 74 and mud cover was low (P = 0.006), while a THI higher than 74 and a low mud cover had independent effects on body temperature (P = 0.012 and 0.004, respectively). In lactation, sows that spent an entire observation period in the farrowing hut also had a higher respiratory rate than sows that left the hut at least once (P = 0.009). In summary, lactating sows were more likely to show increases in respiratory rate and body temperature in warmer conditions than gestating sows, and our findings also suggest that time in the farrowing hut may be a risk factor for heat stress. However, mud cover may limit these physiological consequences when sows have access to a wallow.

A survey of dairy cattle farmers' management practices for cull cows in Ontario, Canada.

Removal of cows from dairy cattle production is a routine and unavoidable practice of the dairy industry and is often referred to as culling. The objectives of this study were to use a survey to describe current on-farm cull cow management, farmers' perception of cull cows' journeys to slaughter, and the adoption of current recommendations and regulations by Ontario dairy farmers. All Ontario dairy farmers were invited to complete a cull cow management survey between December 2020 and March 2021 that included 44 questions covering farmer demographic information, farm characteristics, and cull cow management. The survey response rate was 7.4% (n = 248); a total of 226 of the responses were included in this study for analysis. Most respondents indicated they have a written standard operating procedure (SOP) for cull cows (62%), and 48, 13, and 15% of those identified they use their cull cow SOP "always," "sometimes," and "never," respectively. The more confident respondents were that cull cows arrived at slaughter in the condition they left the farm the less likely they were to have a cull cow SOP [odds ratio (OR) 0.83]. The most important sources of information for the management of cull cows were the herd veterinarian (64%) and members of the marketing/regulatory organization the Dairy Farmers of Ontario (44%). Drug withdrawal time was the only factor most respondents (73%) considered "very important" for the assessment of cull cows prior to transport. Most farmers believe cull cows journey from the farm to slaughter is three or less days (55%), and the confidence of farmers that cull cows arrive at slaughter in the condition they left their farm was generally high. Lastly, most farmers (66%) identified they were familiar with recent regulatory changes around the fitness, duration of transport, and lactation status for cull cows. These results highlight farmers' perceptions of the impacts and durations of the journey of cull cows differs from reality, and there are misunderstandings of the requirements for cull cow management. Further research should investigate how different strategies for training farmers may lead to improved cull cow welfare and regulatory compliance.

Case-control study of behavior data from automated milk feeders in healthy or diseased dairy calves.

Group housing of preweaning dairy calves is increasing in popularity throughout the dairy industry. However, it can be more difficult to individually monitor calves to identify disease in these group systems. Automated milk feeders (AMF) not only provide producers with the opportunity to increase the milk allowance offered to preweaning calves but they can also monitor individual feeding behaviors that could identify calves at increased risk of disease. The objective of this retrospective case-control study was to determine how feeding behaviors change in preweaning calves leading up to and during a disease bout. This study was conducted between fall 2015 and fall 2016 on 2 commercial dairy farms in Ontario, Canada. Producers' treatment records for respiratory or enteric illness were used to identify cases. Control calves were selected from calves not treated for disease and matched on the days on the AMF. Both farms housed calves in dynamic groups of 9 to 11 calves with an AMF and fed milk replacer. Differences in feeding behaviors, including milk consumption, drinking speed, rewarded visits, unrewarded visits, and total visits to the AMF per day, were analyzed by mixed models accounting for repeated measures. Data were analyzed for the 7 d before, the day of, and 7 d after treatment. A total of 28 cases and 28 control calves (n = 56) were analyzed. Calves with disease consumed significantly less milk than their healthy counterparts, beginning 5 d before disease and until 3 d after disease detection. Sick calves had fewer unrewarded visits starting 3 d before until 2 d after illness detection. Sick calves drank significantly more slowly starting 4 d before illness detection until the day after illness detection compared with healthy controls. No differences were found between cases and controls for rewarded visits. Calves on a high plane of milk nutrition significantly alter feeding behaviors before illness detection. Data from AMF on feeding behaviors may help to detect disease earlier in preweaning dairy calves.

Effect of rest, post-rest transport duration, and conditioning on performance, behavioural, and physiological welfare indicators of beef calves.

The aim of this study was to assess the effects of conditioning, rest, and post-rest transport duration on welfare indicators of 6-7 mo old beef calves following a 20-h transport. Three hundred and twenty-eight weaned calves (237 ± 29.7 kg of BW) were randomly assigned to a 2 × 2 × 2 nested factorial design: conditioning, conditioned (C) or non-conditioned (N); rest, 0 (R0) or 8 (R8) h, and post-rest transport, 4 (T4) or 15 (T15) h. Calves were sampled before (LO1) and after (UN1) the initial 20-h journey, before (LO2) and after (UN2) the additional 4 or 15-h journey, and at 1, 2, 3, 5, 14, and 28 d after UN2. Data was analyzed using the GLIMMIX procedure of SAS. Fixed effects included conditioning, transport, and time nested within rest period, while random effects included animal and pen. Greater shrink (p < 0.01) was observed in C than N calves after the initial 20-h transport. During the first week after transportation, the mean ADG of N calves was greater than C calves (p < 0.01). From d 14 to d 28, however, the mean ADG of C calves was greater than N calves (p < 0.01). Flight speed, cortisol and L-lactate concentrations were greater (p ≤ 0.05) in C than N calves between LO1 and d 5, while greater (p ≤ 0.02) non-esterified fatty acids, creatine kinase, serum amyloid-A, and haptoglobin concentrations were observed in N than C calves between LO1 and d 3. The R8-T4 calves had greater (p < 0.01) ADG than R8-T15 calves between LO1 and d 5. The R0-T4 calves had greater L-lactate concentrations than R0-T15 and R8-T4 calves (both p = 0.02) on d 1. The R0 calves had greater (p < 0.01) ADG than R8 calves between 14 and 28 d. This study suggests that C calves are better fit for transport than N calves as evidenced by behavioural and physiological parameters. Fewer and inconsistent differences were observed for rest and post-rest transport treatments.