Incidence of lameness and association of cause and severity of lameness on the outcome for cattle on six commercial beef feedlots

The Risk Factors of Dewclaw Dermatitis in Beef Cattle in the Amazon Biome

Bovine Dewclaw Dermatitis (BDCD) is a hoof disease characterized by inflammation of the second and fifth accessory digits and the skin in this region. This pathology is poorly described in the literature; however, it has recently been observed in beef cattle in the Amazon Biome, Brazil. The objective of this study was to perform a clinical diagnosis and identify the risk factors associated with BDCD onset in cattle in the studied biome. Samples were collected from eight farms with extensive breeding systems located in Xinguara, Rondon do Pará, Curionópolis, and Ipixuna do Pará in the state of Pará, Brazil. A total of 706 Nellore and Nellore crossbred with taurine bovine of both sexes were evaluated, with males aged between 2 and 4 years and a mean weight of 650 kg, and females aged between 2 and 11 years and a mean weight of 400 kg. Distal extremities were inspected during cattle management, and in cases of dewclaw lesions, a specific examination was carried out after proper restraint. Cattle were diagnosed with BDCD on all farms analyzed. Of the 706 cattle inspected, 49 (6.94%) showed BDCD, of which 19 (38.77%) were Nellore and 30 (61.22%) were crossbred. This was the first study to determine BDCD's occurrence in extensive farming systems in the Amazon region, also showing that pastures with large amounts of stumps and stones, the physical structure of pens, and trauma and injury incidence during animal management are the most important predisposing factors for the onset of BDCD.

Epidemiology of Digital Dermatitis in Western Canadian Feedlot Cattle

Digital dermatitis (DD) is an emerging disease in feedlot cattle. Our objective was to identify animal- and feedlot-level risk factors for DD by analyzing individual animal health records (n = 1,209,883) and feedlot-level records from western Canadian feedlots (n = 28) between 2014 and 2018, inclusive. The risk of a DD diagnosis was higher (incidence rate ratio (IRR) = 2.08, 95% CI 1.52 to 2.86) in cattle sourced from confined background operations (CB) versus cattle sourced from auction markets (AM). Conversely, ranch direct (RD) cattle were (IRR = 0.02, 95% CI 0.04 to 0.30) lower risk than AM cattle of being diagnosed with DD. The risk of being diagnosed with DD was higher in females than in males. The magnitude of the risk in females over males was influenced by annual DD incidence in low morbidity years (2014, 2017, and 2018) (IRR = 2.02, 95% CI 1.27 to 3.19), medium morbidity years (2016) (IRR = 2.95, 95% CI 1.64 to 5.33), and high morbidity years (2015) (IRR = 5.41, 95% CI 3.27 to 8.95). At the feedlot-level, the risk of a diagnosis of DD was lower in small capacity (SCF) versus large capacity feedlots (LCF) (IRR = 0.24, 95% CI 0.05 to 0.76). Future research should focus on identifying factors that may propagate disease transmission between cattle of different sexes and from different acquisition sources.

Evaluation of Claw Lesions in Beef Cattle Slaughtered in Northern Portugal: A Preliminary Study

Claw diseases have a profound impact on cattle welfare, affecting behaviors such as grazing, rumination, rest, decubitus, and water consumption. This study aimed to assess the prevalence of claw lesions and classify them according to the ICAR Claw Health Atlas (International Committee of Animal Recording) in two slaughterhouses. The influence of claw lesions on carcass weight, classification, and fat deposition was also examined. Involving 343 crossbreed cattle from 103 different extensive or semi-intensive farms, this study found an animal prevalence of claw disorders at 65.8%, with a higher incidence in females (n = 207, 60.35%) compared to males (n = 136, 39.65%). Despite the observed prevalence, claw lesions were not influenced by age or sex (p > 0.05). The main claw lesions identified, including heel horn erosion, double sole, and asymmetric claw, were consistent with the cattle management practices in the study area. These cattle were raised in small, rustic premises with uneven floors, utilizing a mix of manure and plant material as bedding and lacking access to pasture. Also, no negative economic impact was detected concerning carcass weight, classification, or fat deposition. Consequently, it was concluded that the presence of claw lesions in beef cattle raised under the characteristic management of this geographical area does not adversely affect animal health or farm economics.

Modification of Domestic Animal Lameness Scales for Use in Asiatic Black Bears (Ursus thibetanus)

Lameness in animals is a welfare concern as it can be an indicator of pain. A standardized bear lameness scale would significantly improve the ability of facilities that house bears to monitor, manage, and treat lameness in their animals. The Animals Asia bear rescue center in Vietnam holds over 180 rescued bears with varying health and mobility conditions as a result of the illegal bear bile trade, and a reliable lameness assessment system was needed. Bear locomotion includes a lumbering gait, which differs from domestic animal locomotion, necessitating the modification of domestic animal lameness scales, and a five-point lameness scale was developed. Professionals from various veterinary-related backgrounds scored bear lameness videos to assess interobserver reliability and the intraclass correlation coefficient indicated good to excellent reliability. A 15-min training video with examples of lameness and grades was provided before assessment. The lameness scale developed herein addresses the lack of a published lameness scale for bears, and, due to the similar locomotion of the genus, can be used on any bear species. This scale is a consistent and reliable tool for evaluating and documenting lameness in addition to monitoring response to treatment. It will benefit bear welfare by indirectly characterizing the level of pain a bear is experiencing due to lameness as well as serving to document trends in pain status.

Antimicrobial use in 20 U.S. beef feedyards: 2018-2019

The objective of this study was to report antimicrobial use in a convenience sample of U.S. beef feedyards for the years 2018 and 2019. In addition to antimicrobial use metrics, also reported are the indications for antimicrobial use and outcomes related to these indications. Antimicrobial use is characterized at the study and feedyard levels for a total of 1,141,846 head of cattle in 20 U.S. feedyards. Antimicrobial use is reported as milligrams of active antimicrobial ingredient per kilogram of liveweight sold (mg/kg-LW) and regimens of antimicrobials per animal year (Reg/AY). Regimens are described by antimicrobial class within use category as characterized by mg of active antimicrobial product per regimen (mg/Reg) and calendar days of administration per regimen (CDoA/Reg). A total of 1,128,515 regimens of medically important antimicrobials were captured from records. The number of regimens/100 head-in (Reg/100 head-in) are described in a subset of 10 feedyards with adequate data granularity to directly determine indications for antimicrobial administration. For the indications of bovine respiratory disease (BRD), Lameness (Lame), Liver Abscess Control (LAC), and Other (e.g., central nervous system disease, cellulitis) the Reg/100 head-in study-level values are 37.1, 0.8, 98.4, and 0.7, respectively, for 2018, with similar values for 2019. The regimens for BRD are further categorized in these 10 feedyards by the use categories in-feed, control of BRD, and individual animal therapy, yielding study level values of 4.6, 19.6, and 12.9 Reg/100 head-in, respectively, for 2018, with similar values for 2019. Outcomes of therapy for individual animal treatment of BRD, Lame, and Other are reported as treatment success, retreatment, or mortality by 30 days after the initial therapy of an animal for a disease. Treatment success rates (no treatment or mortality in the next 30 days) for 2018 in the 10 feedyards with sufficient data granularity are 76.5, 86.5, and 83.0% for BRD, Lame, and Other, respectively. The comparison of these results with other reports of antimicrobial use in North American feedyards highlights how differing approaches in calculating metric values may result in substantially different conclusions regarding antimicrobial use, especially in relation to long-duration uses.

Variability of gait characteristics in lameness elephant

Lameness has a significant impact not only on the economy but also on elephant welfare. Several gait characteristics are altered to compensate for the discomfort. The traditional approach to detecting lameness has relied on mahout and veterinarian observation. The study aimed to determine how lameness affected the variability of an elephant's gait by using a three-dimensional inertial measurement unit (IMU) with Wi-Fi sensors. Five elephants with lameness, as determined by an experienced veterinarian and two, non-lamed elephants, aged between 58-80 years were included in the study. Gait biomechanics including limb segment motion, obtained from individually gyrometric- and accelero-based parameters and demonstrated as a graphical pattern showing changes in absolute rotation angle over time. The result revealed some character changes in gait kinematics parameters, but it was heterogeneity with an inconclusive pattern. The interlimb coordination could be a part of maintaining the actual locomotion pattern, or it could be a result of the mild degree of lameness for which all of the clients have compensated. This study introduces a new objective method for quantifying gait changes caused by lameness, additional research is required to make this objective more clinically applicable.

The association of multiple metrics for evaluating antimicrobial use in U.S. beef feedyards

In order to accurately portray antimicrobial use in food animals, the need for standardized metrics, and an understanding of the characteristics of different metrics, has long been recognized. Fourteen U.S. feedyards were used to evaluate the effects of using centralized constants such as defined daily dose (DDD) and defined course dose (DCD) applied to the weight of medically important antimicrobials by class (mg) as opposed to using electronic individual animal treatment records and lot level in-feed antimicrobial records obtained from the same population. Three numerators were calculated directly from recorded data for each drug product: the number of antimicrobial regimens associated with indication (Reg), milligrams of drug administered per regimen (mg), and calendar days of administration for each regimen (CDoA). There were four use indications to which numerators were assigned: liver abscess control (LAC), bovine respiratory disease (BRD), lameness (lame), or all other indications combined (other). Three denominators were also calculated directly from the data, these being the number of days animals were present (head days), number of cattle received (head in), and kilograms of live weight sold (kg-LW). Numerators and denominators were calculated at the lot level. The use of DDD or DCD was explored to determine how their use would affect interpretation of comparisons between lots or feedyards. At the lot level across both study years, the lot estimate of nDDD differed from the CDoA value by >25% in 49.2% of the lots. The number of Defined Course Doses (nDCD) was then compared to the number of Regimens (Reg). Comparing nDCD to Reg at the lot level across both study years, the lot estimate of nDCD differed from the Reg value by >25% in 46.4% of lots. Both year and metric were also shown to affect numerical feedyard ranking by antimicrobial use according to seven different metrics. The analysis reported here adds to the body of literature reporting substantial effects of metric choice on the conclusions drawn from comparing antimicrobial use across multiple production sites.

Changing interventions in farm animal health and welfare: A governmentality approach to the case of lameness

Lameness is a significant health and welfare issue in farmed animals. This paper uses a governmentality approach, which focuses on how a problem is made governable, to examine an emerging 'ecology of devices' introduced to intervene in, and attempt to reduce, on-farm incidence of lameness. These devices are associated with advisers who work with farmers on-farm; they enact lameness as a governable entity, are tools to assess the existence of lameness against established norms, and prescribe actions to be taken in response to evidence of lameness. In doing this they subjectify farmers and advisers into seeing and responding to lameness in particular ways. Using concepts of governmentality alongside other perspectives on the power relations and the simplifications and complexities involved in interventions in animal health and farm practice, the paper draws on in-depth research with advisers including vets and other paraprofessionals who work with farmers, and their cows and sheep. It explores how this set of devices introduces particular techniques and practices in lameness management, and produces farmer and adviser subjectivities. It then explores some of the problematics of this mode of governing lameness, including analysis of the limitations and unintended consequences of attempts to simplify lameness management. The paper concludes by arguing that its approach is valuable in analysing ongoing intensification of interventions in farming practices and in understanding the limits of such interventions and the unanticipated divergences from expected conduct.

An experimental model to induce digital dermatitis in beef calves

Background

Digital dermatitis (DD) is a multifactorial infectious disease affecting the skin on feet of cattle causing erosion and inflammation above the heel bulbs. Some cases of DD cause lameness and significantly impact animal welfare and productivity. While DD has emerged as a concern for the beef industry, key information regarding early detection and its impact on cattle behaviour is lacking. The primary objective of this study was to determine if an established DD experimental model for dairy calves could be used to induce DD lesions in beef calves. A secondary objective was to describe changes in behaviour and pain associated with induction of DD lesions. Eight beef calves acquired from a single cow-calf operator were enrolled in the study. Upon enrolment, calves were evaluated and determined to be free of foot lesions. Within the experimental environment, calves were housed in individual pens and assigned to two groups (mock-inoculated and inoculated). Both hind feet of each calf were enrolled. Within calf, inoculation protocol was consistent, and a 28-day experimental protocol was employed. Two days prior to inoculation, both hind feet of each calf were abraded (area above the heel bulbs and below the dewclaws), moistened, and wrapped to facilitate an anaerobic condition. Feet were inoculated with macerated DD lesion material or mock inoculum and remained wrapped until clinical signs of DD or protocol endpoint.

Results

After a period of 14 to 18 days post inoculation, three of five inoculated calves developed clinical signs (lameness), and upon close inspection, DD lesions were present on at least one hind foot. Two of five inoculated calves did not develop lesions within 28 days. Zero of three mock-inoculated calves developed DD. Treponema spp. were detected by quantitative polymerase chain reaction from biopsies of induced lesions. Measurements of behaviour prior to disease induction were numerically different between DD affected and mock-inoculated calves.

Conclusions

An experimental infection model established for dairy cattle was used to successfully induce acute DD lesions in three of five inoculated beef calves. This model can provide a framework to study intervention protocols and to evaluate the impact of DD on behaviour and pain.

Occurrence of foot diseases in cattle attended at the Clínica de Bovinos de Garanhuns: Epidemiological, clinical, therapeutic and economic aspects

Abstract The objective was to study the occurrence of foot disorders in cattle treated at the Clínica de Bovinos de Garanhuns, campus of the Universidade Federal Rural de Pernambuco from 1999 to 2021. A retrospective study of the medical records was carried out, with a total of 334 cases, in which 613 lesions were diagnosed. A frequency distribution, with simple mean and standard deviation was performed to evaluate the data. Interdigital dermatitis was more frequent in 12.4% (76/613), double sole in 9.79% (60/613), chronic laminitis in 8.81% (54/613), sole ulcer in 7.83% (48 /613), and interdigital hyperplasia in 7.24% (45/613). Laminitis and its consequences accounted for 45% of the total injuries identified, followed by 36% of injuries of secondary or uncertain cause, and 19% from infectious diseases. The distribution of lesions between the limbs was 68% in the pelvic and 32% in the thoracic limbs. Females, raised in a semi-intensive system, Holstein, with a body score of III, and large size were more affected. Lameness was present in 78% (260/334), while 10% (33/334) did not present lameness. The case fatality and recovery rates were 9% (31/334) and 73% (243/334), respectively. In total, 51% of cases occurred in the rainy season and 49% in the dry season. The main cities of origin were Bom Conselho 22.75% (76/334), Garanhuns 18.86% (63/334), and Brejão 12.57% (42/334). The estimated cost of treatment was US$ 150.13/case. Diseases are probably directly linked to management failure on the property due to the nature of the diagnosed diseases, in addition to the significant cost of the treatment of these animals, with the need for prophylactic measures in order to avoid the economic losses associated with foot diseases.

Ocorrência de afecções podais em bovinos atendidos pela Clínica de Bovinos de Garanhuns: aspectos epidemiológicos, clínicos, terapêuticos e econômicos

Resumo Objetivou-se estudar a ocorrência das afecções podais em bovinos atendidos na Clínica de Bovinos de Garanhuns, Campus da Universidade Federal Rural de Pernambuco, no intervalo de 1999 a 2021. Realizou-se estudo retrospectivo dos prontuários, com total 334 casos, dos quais foram diagnosticadas 613 lesões digitais. Foi realizada a distribuição de frequência, média simples e desvio padrão para avaliação dos dados. A dermatite interdigital foi a mais frequente, sendo observada em 12,4% (76/613) dos casos, seguida por sola dupla 9,79% (60/613), laminite crônica 8,81% (54/613), úlcera de sola 7,83% (48/613) e a hiperplasia interdigital 7,24% (45/613). A laminite e suas consequências representaram 45% do total de lesões identificadas, acompanhadas por 36% das injúrias de causa secundárias ou incertas e de doenças infecciosas com 19%. A distribuição das lesões entre os membros foi de 68% nos pélvicos e 32% nos torácicos. As fêmeas criadas em sistema semi-intensivo, holandesas, com escore corporal III e porte grande eram mais acometidas. A claudicação estava presente em 78% dos animais, enquanto 10% não claudicavam. As taxas de letalidade e recuperação foram de 9% (31/334) e 73 % (243/334), respectivamente. No período chuvoso foram 51% dos casos e 49% na época seca. Os principais municípios de origem foram Bom Conselho 22,75% (76/334), Garanhuns 18, 86% (63/334) e Brejão 12,57% (42/334). O custo estimado com tratamento foi de US$ 150,13/caso. Provavelmente falhas de manejo nas propriedades foram importantes fatores de risco para as doenças. Sugere-se a implementação de medidas profiláticas para evitar as perdas econômicas associadas às enfermidades podais.

A prospective longitudinal study of risk factors associated with cattle lameness in southern Alberta feedlots

The objectives of this study were to determine the incidence proportion of lameness in feedlot cattle and the associated risk factors. Lameness was studied in two southern Alberta feedlots over a 2 yr period. The incidence proportion of lameness was 36.3% for all calves pulled for treatment. Risk factors associated (P < 0.0001) with increased lameness included body weight (BW), type of cattle, source, stocking density, percentage of forage in the diet, season, precipitation 1 d before diagnosis, and average temperature range 3 d prior to diagnosis. As BW (P < 0.001) increased, the odds of becoming lame also increased. Yearlings and Holsteins had greater (P < 0.001) incidence of lameness than respiratory disease. The odds of becoming lame decreased (P < 0.001) with increased pen density and percentage of forage in the diet. Lameness was greatest in spring (P < 0.001) with the odds of becoming lame being more likely (P < 0.001) with increased precipitation and temperature range (P < 0.001). Use of a multifactorial approach including animal, managerial, and environmental factors in a single analysis will improve our understanding of the risk of increased lameness and aid in development of strategies to reduce its incidence in feedlots.

Economic impact of digital dermatitis, foot rot, and bovine respiratory disease in feedlot cattle

Digital dermatitis (DD) has emerged in North American feedlots, although production and economic impacts are not fully understood. Objectives of this study were to: (1) estimate the economic impact of a single case of DD, foot rot (FR), and bovine respiratory disease (BRD) in feedlot cattle and (2) determine its impact on average daily gain (ADG). Feedlot cattle health and production records were available from two feedlots for a 3-yr interval. The dataset consisted of 77,115 animal records, with 19.3% (14,900) diagnosed with a disease. Diseased animals were categorized into five groups: DD, FR, BRD, other diseases (OT), and two or more diseases (TM), with a treatment cumulative incidence of 6.0%, 59.1%, 10.7%, 12.7%, and 11.5%, respectively. FR was the disease with the highest cumulative incidence in both heifers and steers (58.8% and 59.6%, respectively). Of all fall-placed cattle diagnosed with any disease, 48.1% of the cases were FR. DD affected the partial budget in five out of the eight groups of cattle, with the highest impact of DD seen in grass yearling heifers and grass yearling steers: $-98 and $-96 CAD, respectively, relative to their healthier counterparts. Healthy cattle had a significantly higher ADG when compared with DD cattle in five of the eight categories, ranging from 0.11 kg/d in winter-placed heifers to 0.17 kg/d in fall-placed steers. In the economic analysis, it was concluded that on an individual animal basis, BRD was the most impactful of all analyzed diseases, whereas DD was second, marking the importance of controlling and mitigating this foot condition. Identifying differential effects of diseases on a partial budget analysis and ADG of the types of cattle stratified by sex enables feedlot producers to focus control and mitigation strategies on specific groups.

Risk factors of digital dermatitis in feedlot cattle

Digital dermatitis (DD) has been reported in North American feedlots, although risk factors are not well characterized. Our objectives were to analyze: (1) foot and leg conformation and (2) pen hygiene, as potential variables that predispose feedlot cattle to DD. Production parameters in DD-affected cattle were compared with healthy cattle and with those diagnosed with more commonly known infectious lesion foot rot (FR). In total, 2,854 feedlot cattle in 11 pens in 2 feedlots were assessed (bi-weekly pen walks) throughout the feeding cycle. Pen condition was categorized as: “dry,” “mud present but has good bedding,” “more mud than bedding,” and “excessive mud.” Gait scoring was competed and cattle with abnormal gait or evident foot lesions (i.e., DD or FR) were restrained in a cattle chute for a close foot inspection (n=280), including scoring of foot angle and claw set and hind and side views of rear feet and legs. Cumulative incidence of DD (present or absent) and FR was 2.5% (71/2,854) and 11.6% (331/2,854), respectively. Foot and leg conformation was not significantly different between left and right sides or between cattle with (n=71) and without DD (n=209). Lameness was diagnosed in only 22% of cattle with DD. Cattle with DD gained 0.27 kg/d less compared with healthy cattle (mean ± SD: 1.29 ± 0.29 vs. 1.56 ± 0.27, P<0.05) and 0.4 kg/d less compared with FR (1.29 ± 0.29 vs. 1.69 ± 0.25). Presence of DD was not significantly different between pens with “dry” and “mud present but has good bedding,” but for pens with “more mud than bedding” or “excessive mud,” the risk of cattle having DD cases increased significantly [odds ratio (OR)=8.55, confidence interval (CI): 4.0–18.4 and OR=14.1, CI: 5.9–33.8, respectively]. In conclusion, it is important to keep good pen conditions to reduce the risk of DD, which can be managed through proper stocking density and strategic bedding, irrespective of foot and leg conformation.

Tracking Reservoirs of Antimicrobial Resistance Genes in a Complex Microbial Community Using Metagenomic Hi-C: The Case of Bovine Digital Dermatitis

Bovine digital dermatitis (DD) is a contagious infectious cause of lameness in cattle with unknown definitive etiologies. Many of the bacterial species detected in metagenomic analyses of DD lesions are difficult to culture, and their antimicrobial resistance status is largely unknown. Recently, a novel proximity ligation-guided metagenomic approach (Hi-C ProxiMeta) has been used to identify bacterial reservoirs of antimicrobial resistance genes (ARGs) directly from microbial communities, without the need to culture individual bacteria. The objective of this study was to track tetracycline resistance determinants in bacteria involved in DD pathogenesis using Hi-C. A pooled sample of macerated tissues from clinical DD lesions was used for this purpose. Metagenome deconvolution using ProxiMeta resulted in the creation of 40 metagenome-assembled genomes with ≥80% complete genomes, classified into five phyla. Further, 1959 tetracycline resistance genes and ARGs conferring resistance to aminoglycoside, beta-lactams, sulfonamide, phenicol, lincosamide, and erythromycin were identified along with their bacterial hosts. In conclusion, the widespread distribution of genes conferring resistance against tetracycline and other antimicrobials in bacteria of DD lesions is reported for the first time. Use of proximity ligation to identify microorganisms hosting specific ARGs holds promise for tracking ARGs transmission in complex microbial communities.

Economic effects of policy options restricting antimicrobial use for high risk cattle placed in U.S. feedlots

The rising public health threat of antimicrobial resistance, the influence of food service companies, as well as the overall lack of positive image of using medical products in intensive farming are major drivers curbing antimicrobial use. In the future, government policies may affect practices of antimicrobial use in beef production in feedlots, a prominent current user of antimicrobials in animal agriculture, but also the agricultural industry generating the highest cash receipt in the U.S. Our objective was to estimate the cost effect from the following policies in feedlots: 1) using antimicrobials for disease prevention, control, and treatment; 2) using antimicrobials only for treatment of disease; and 3) not using antimicrobials for any reason. We modelled a typical U.S. feedlot, where high risk cattle may be afflicted by diseases requiring antimicrobial therapy, namely respiratory diseases, liver abscesses and lameness. We calculated the net revenue loss under each policy of antimicrobial use restriction. With moderate disease incidence, the median net revenue loss was $66 and $96 per animal entering the feedlot, for not using antimicrobials for disease prevention and control, or not using any antimicrobials, respectively, compared to using antimicrobials for disease prevention, control, and treatment. Losses arose mainly from an increase of fatality and morbidity rates, almost doubling for respiratory diseases in the case of antimicrobial use restrictions. In the case of antimicrobial use prohibition, decreasing the feeder cattle price by 9%, or alternatively, increasing the slaughter cattle price by 6.3%, would offset the net revenue losses for the feedlot operator. If no alternatives to antimicrobial therapy for prevention, control and treatment of current infectious diseases are implemented, policies that economically incentivize adoption of non-antimicrobial prevention and control strategies for infectious diseases would be necessary to maintain animal welfare and the profitability of beef production while simultaneously curbing antimicrobial use.

Animal welfare in the U.S. slaughter industry-a focus on fed cattle

Animal welfare within the U.S. slaughter industry continues to prevail as one of the top priorities for livestock producers, businesses, and consumers alike. There are federal regulations that enforce the humane transport, handling, and slaughter of cattle. The journey that cattle must make to the slaughter facility is comprised of many environmental and human factors that can positively or negatively affect animal welfare. Cattle may be exposed to multiple stressors, such as noise, unfamiliar animals and humans, temperature extremes, temporary food/water deprivation, variable transport distances and experiences, and new pen conditions. The animal caretakers involved in these processes attempt to minimize stress and discomfort for the animals, but research is needed to focus on the gaps in knowledge and to support the implementation of strategies known to enhance the human-animal interactions that occur from farm to slaughter. This literature review will provide a summary of fed cattle welfare topics, research, and industry tools that span across the beef animal's journey from the farm/feedlot through the slaughter process. In addition, areas that have had little research focus are identified to highlight the need for future work and development of industry tools. Some of these topics include examining trailer design, the use of trailer slats during weather extremes, the welfare aspects of cattle destined for salvage slaughter, multiple preslaughter factors and interactions, abnormal mobility and nonambulatory cattle, lairage environmental conditions, new stunning methods, and the impact of a well-trained, motivated, and stable workforce on cattle and people welfare. The authors conducted a survey at the 2019 North American Meat Institute Animal Care and Handling Conference, which comprised of stakeholders within the meat packing industry, packing plant employees, and food company employees, educators, and auditors. The survey responses identified training/education and communication as areas of need in animal welfare, whereas the majority of survey responses focused on the aspects of the human-animal interaction as the top challenges for the industry. By continuously identifying, measuring, monitoring, and managing animal welfare challenges within the beef cattle slaughter industry, prioritization and execution of programs and training that improve the welfare of cattle can be achieved as animals move through this final stage of the meat production system.

Investigation of a novel prosthesis technique for extracapsular stabilization of cranial cruciate ligament-deficient stifle joints in adult cattle

OBJECTIVE

To evaluate a novel prosthesis technique for extracapsular stabilization of cranial cruciate ligament (CCL)-deficient stifle joints in adult cattle.

SAMPLE

13 cadaveric bovine stifle joint specimens.

PROCEDURES

In the first of 3 study phases, the most isometric points on the distal aspect of the femur (distal femur) and proximal aspect of the tibia (proximal tibia) were determined from measurements obtained from lateromedial radiographs of a stifle joint specimen maintained at angles of 135°, 90°, 65°, and 35°. During phase 2, 800-lb-test monofilament nylon leader line was cut into 73-cm-long segments. Each segment was secured in a loop by use of 2, 3, or 4 crimping sleeves such that there were 12 replicates for each construct. Each loop was distracted to failure at a constant rate of 1 mm/s. Mean force at failure and elongation and mode of failure were compared among the 3 constructs. During phase 3, bone tunnels were created in the distal femur and proximal tibia at the isometric points identified during phase 1 in each of 12 CCL-deficient stifle joint specimens. The 3-sleeve construct was applied to each specimen. Specimens were distracted to failure at a constant rate of 1 mm/s.

RESULTS

Among the 3 constructs evaluated, the 3-sleeve construct was considered optimal in terms of strength and amount of foreign material. In phase 3, all replicates failed because of suture slippage.

CONCLUSIONS AND CLINICAL RELEVANCE

Use of 800-lb-test monofilament nylon leader line as a prosthesis might be a viable alternative for extracapsular stabilization of CCL-deficient stifle joints in adult cattle. Further in vivo studies are necessary.

Prevalence and lameness-associated risk factors in Alberta feedlot cattle

Lameness in cattle is a health and welfare concern; however, limited information is available on risk factors and the relationship between lameness and common diseases like bovine respiratory disease (BRD). Therefore, the objectives of this study were to: 1) identify prevalence of lameness in feedlot cattle and related risk factors of cattle diagnosed as lame; and 2) determine associations between BRD occurrence and lameness. Feedlot cattle health records were available from 28 feedlots for 10 yr. The data set consisted of 663,838 cattle records, with 13.9% (92,156) diagnosed with a disease, including 32.3%, 46.0%, and 22.0% with lameness, BRD, and other diagnoses, respectively. Lameness was classified into four categories: foot rot (FR), joint infections (JI), lame with no visible swelling (LNVS), and injuries (INJ), with a prevalence of 74.5%, 16.1%, 6.1%, and 3.1%, respectively. Lameness was compared across cattle types (arrival date and weight) as well as age classification (calf vs. yearling), gender (steer vs. heifer), and season of placement in the feedlot (spring, summer, fall, and winter). Within the disease-diagnosed population, lameness represented 28.5% of treated fall-placed calves, 38.5% of winter-placed calves, and 40.8% of treated yearlings. Foot rot was the most common diagnosis with 74.5% of all lameness diagnoses, with winter- and fall-placed calves more likely to be diagnosed with FR compared to yearlings (OR: 1.19, 95% CI: 1.10–1.30 and OR: 1.46, 95% CI: 1.38–1.55, respectively). Joint infections were the second most common diagnosis (16.1%). Compared to yearlings, fall-placed calves had a higher odds (OR: 3.64, 95% CI: 3.12–4.24) for JI. Injuries and LNVS were the least common but again fall-placed calves had higher odds of this diagnosis compared to yearlings (OR: 2.26, 95% CI: 1.70–2.99 and OR: 9.10, 95% CI: 6.26–13.2, respectively). Gender was significantly different for JI as steers were less likely affected compared to heifers (OR: 0.687, 95% CI: 0.545–0.867), and more likely affected by LNVS (OR: 2.46, 95% CI: 1.57–3.84). Of all lameness-associated deaths, JI accounted for almost 50%. Finally, cattle diagnosed with BRD were subsequently more likely to be diagnosed with INJ, JI, or LNVS (P < 0.001 for all comparisons). In conclusion, animal type and gender were associated with type of lameness diagnoses, allowing feedlots to allocate resources to groups at highest risk and focus on early intervention strategies.

Factors associated with septic arthritis of the distal interphalangeal joint in beef cattle: A case-control study

Lameness in cattle is a welfare concern and is associated with important economic losses in beef cattle operations. Infection of the distal interphalangeal joint (DIJ) results in severe lameness and if left untreated carries a poor prognosis. Diagnosis of DIJ infection is challenging in the field. The aim of this study was to determine factors associated with septic arthritis of the DIJ in beef cattle. Thirty-nine beef cattle with a complaint of single-foot lameness were used in this study. History and lameness examination data were recorded and analyzed. Radiographic changes and cytology of synovial fluid of the affected DIJ were used to define the presence (cases) or absence (controls) of DIJ infection. Asymmetric swelling at the coronary band of the affected foot and a lameness score of ≥4/5 significantly increased the odds (odds ratio [OR]=63.2 and OR=120, respectively) of diagnosis of septic arthritis of the DIJ in beef cattle with a single-foot lameness compared to cattle with no asymmetry of the coronary band or lameness scores <3. Routine lameness examination findings could be used in the field to rapidly recognize infection of the DIJ in lame beef cattle.

Economic impacts of lameness in feedlot cattle

Lameness is an important health issue in feedlot cattle; however, there is a paucity of information regarding its economic impact. Decision tree models are excellent tools for assessing costs of disease such as the net return (net return = benefit – cost). Models were developed using expert opinion, literature and retrospective feedlot data provided by Vet-Agri Health Services (VAHS, Airdrie, Alberta, Canada) collected from 2005 to 2015 on individually treated cattle (n = 30,940) from 28 feedlots. The objective was to estimate net return of various lameness diagnoses and impacts of cattle type, season of treatment, and extreme high and low cattle prices. Cattle were diagnosed as lame according to the following categories: foot rot, foot rot in heavy cattle (BW > 363 kg at treatment), injury, lame with no visible swelling, and joint infection. Records consisted of arrival and treatment weight, cost of treatment, and cattle deaths. Records included cattle types classified as: fall calves (heifer and steer), winter calves (heifer and steer) and yearling cattle (heifer and steer). Lastly, variables ADG, days on feed (DOF), and Season (spring, summer, fall, and winter) were created. Models estimated net return using cattle slaughter prices for healthy cattle that reached a slaughter weight of 635 kg and for three possible outcomes for each diagnosis after final treatment: cattle that recovered after treatment and reached a slaughter weight of 635 kg; cattle that were removed before they reached slaughter weight; or cattle that died. Compared to undiagnosed cattle with 1.36 kg/d ADG, cattle diagnosed with foot rot and foot rot heavy cattle had the highest ADG until first treatment (1.14 and 1.57 kg/d, respectively) and differed significantly (P < 0.05) compared to cattle diagnosed with injuries (0.87 kg/d), lame with no visible swelling (0.64 kg/d), and joint infections (0.53 kg/d). Yearling steers had the most positive returns compared to all other cattle types. Cattle with lighter arrival weight had lower ADG and increased economic losses after treatment compared to heavier weighted cattle on arrival. Based on average slaughter prices over a 10-yr period for healthy cattle, return was $690. Return after final treatment for cattle with foot rot was $568, foot rot in heavy cattle was $695, and injury was $259. However, joint infections and lame with no visible swelling had negative returns of –$286 and –$701, respectively.