Lameness and Welfare of Cattle: Extension Program Activities and Accomplishments

Lameness of dairy and beef cattle continues to be an extension program priority. Over the previous 12 month period, we conducted 10 training programs (under the heading of the ISU Master Hoof Care Program) on foot care and claw trimming to trimmers and dairy farm managers throughout the United States. Most of these programs are conducted in Spanish to address the needs of the dairy industry’s multi-cultural workforce. Similar programs were provided to veterinary students at Iowa State University, the University of Minnesota and the University of Florida. These programs consist of approximately a half day of classroom and 1 to 2 days of claw trimming on cadavers and live animals. Beyond these, multiple on-farm visits were conducted to review lameness problems and/or foot care programs in Iowa and elsewhere in the US. Lameness of cattle has also been the subject of presentations delivered at Iowa Dairy Days and multiple other conferences in Iowa and beyond

Veterinary Extension Program Activities and Accomplishments:Lameness and Welfare of Cattle

In the dairy industry, prevalence of lameness averages somewhere between 20-25% with much higher rates reported in problem herds. Direct effects of lameness are responsible for approximately 15% of cows involuntarily culled from dairy herds. However, when the indirect effects of lameness on milk yield and reproductive performance are considered, involuntary losses associated with impaired locomotion are estimated to increase by an additional 50%. Lameness is therefore recognized as the single most costly clinical disease of dairy cattle (Guard, 2009). The Master Hoof Care Program (now in its 17th year) was designed to address lameness problems on dairies by assuring that foot care technicians are properly trained and equipped to handle common lameness disorders. Over the previous 12 month period, we have conducted multiple training programs (under the heading of the ISU Master Hoof Care Program) on foot care and claw trimming to trimmers and dairy farm managers throughout the United States. The format of these programs consists of approximately a half day of classroom and 1 to 2 days of claw trimming on cadavers and live animals. All training programs are conducted in both English and Spanish and intended to address the needs of the dairy industry’s multicultural workforce. Since large dairies with multiple farm units may have as many as 5 to 10 people serving the foot care needs of the enterprise, on-farm training of foot care technicians may be conducted at the farm of origin with lameness disorders and equipment unique to their workers. Demand for these programs in Iowa has been limited in part because most trimming and foot care is conducted by veterinarians and trimmers. While it is anticipated that this may change as herds get larger, for now the greater need and opportunity lies with the feedyard industry as conditions such as digital dermatitis are becoming major causes of lameness

Lameness and Welfare of Dairy Cattle

A prominent veterinary researcher from Cornell University estimates that the most costly diseases of dairy cattle are displacement of the abomasum and lameness resulting in the $489 and$478 per case, respectively. However, when economic losses are computed on a herd basis, none rival lameness as the most costly disease of dairy cattle. Reasons for this are largely related to its insidious nature and the relatively high incidence of this disease compared to abomasal displacement, mastitis and other common health disorders. Although variable, it is not uncommon to find herds with annual incidence rates of 30% or higher. Lameness disorders are often neglected because early symptoms are subtle causing a failure of owners to observe or recognize them in timely manner. Detection is also complicated by the cow’s natural instinct to disguise her discomfort which results in only mild alterations of gait and posture. Ultimately, this leads to treatment delays and the development of more serious conditions that increase animal suffering and reduce welfare. Despite its impact on performance, profit and animal well-being, attention to this health problem by the dairy industry is lacking. For example, dairy record-keeping systems are designed to capture multiple bits of information on most health disorders in dairy cattle with exception of lameness events. Data that is recorded is usually provided by trimmers, but much of it cannot be conveniently transferred to the farm’s record-keeping system. Furthermore, terms used by trimmers and data captured is not consistent or easily interpreted since there is no standard nomenclature used amongst trimmers. As a consequence, there is little or no data available for regular evaluation of foot care information on farms by veterinarians or others. Another issue of growing concern for the Iowa dairy industry is that promulgated by activist organizations charging that the welfare of animals in production agriculture is compromised for the benefit of profit. These organizations are well organized and support their arguments with video footage taken by persons working undercover in packing plants, livestock markets and on farms. For the most radical of these organizations the primary objective is to end animal agriculture. Unless the dairy industry can develop an effective pro-active approach to assuring consumers of its commitment to humane care of its animals, it faces a greater likelihood of increased regulation by outside agencies

Survey of Veterinarians and Hoof Trimmers on Methods Applied to Treat Claw Lesions in Dairy Cattle

A survey inquiring about treatment approaches for claw horn lesion in dairy cattle was available to veterinarians and hoof trimmers who were members of either the American Association of Bovine Practitioners (AABP) or the Hoof Trimmers Association (HTA) during the winter of 2013. The study showed differences among AABP and HTA members with regards to procedural training and technique as well as treatment approach. No differences were noted when evaluating the use of topical medications along with bandaging materials, but details regarding the types of topical medications used did reveal discrepancies among the AABP and HTA members

Deciphering Digital Dermatitis

Bovine digital dermatitis (DD) is a leading cause of lameness in dairy cattle throughout the world. Despite more than 40 years of research, the definitive etio- logic agent associated with the disease pro- cess is still unknown. Previous studies have demonstrated that multiple bacterial species are associated with lesions, with spirochetes being the most reliably identified organism. According to the most recent National Animal Health Monitoring System survey of U.S. dairy farms, lameness is the second most common health problem identified in dairy cattle. DD was found to be the primary cause of lameness within the study herds, account- ing for 61.8% of the lameness in bred heifers and 49.1% of the lameness in cows. Recently, the condition has become increasingly com- mon in feedyard cattle as well, particularly in heavy cattle nearing slaughter weights, although it can be seen in cow–calf opera- tions as well

Perspectives on the Treatment of Claw Lesions in Cattle

Lameness is a leading cause of welfare and culling issues in cattle, with claw lesions accounting for the majority of these issues. Although the treatment of claw lesions in cattle is a daily activity for hoof trimmers, veterinarians, and livestock producers, there is surprisingly little information in the peer-reviewed literature on which to base strong evidence-based conclusions. As a consequence, many treatment modalities used are empirical and, in some cases, may be counterproductive to rapid lesion healing. Furthermore, many of these empirical treatment modalities fail to fully consider the underlying pathogenesis of the disease process and the implications that it has on lesion healing. For example, sole ulcers are largely a consequence of metabolic disorders and mechanical overloading. Therapeutic interventions that fail to address the weight-bearing issues are unlikely to be successful. Likewise, white line disease is believed to be predisposed by rumen acidosis and laminitis, and interventions need to include in them appropriate measures to prevent further cases through nutritional management. The goal of this review paper is to review the pathogenesis of claw lesions in the context of the published literature and allow the reader to arrive at rational treatment interventions based on the best available information. The use of an orthopedic block applied to the healthy claw of a lame foot, judicious use of bandage or wrap, careful selection of parenteral or topical therapy, and a treatment protocol to manage pain and promote recovery are key components of responsible management of lameness disorders in cattle

Efeito do casqueamento na distribuição de pressões e suporte de peso na superfície dos cascos de vacas leiteiras

Claw lameness can be associated to biomechanical factors caused by unbalanced pressure distribution under the hooves when cows are confined in modern dairy operations with hard concrete flooring. In the present study, an original claw subdivision4 was slightly modified to differentiate between the anterior (typical sole lesion spot) and posterior portions of the medial sole, and to emphasize the maximum pressures applied only on the area of contact without including the total area within these regions during midstance. The results, obtained showed significance (p < 0.044) for the interaction among Group, Leg and region (G*L*R). It was observed that the rear portion of the claws (heels) on the hind limb of untrimmed cows, are more stressed than the heel region on trimmed cows (23 % versus 16.72% of total pressure applied on the claw for untrimmed and trimmed respectively). The typical sole lesion spot pressures were increased slightly on trimmed cows as compared to untrimmed (20.20% versus 15.9%). The front feet presented differences in pressure concentration on the lateral sole between both groups (29% versus 23.25% for untrimmed versus trimmed respectively). It was concluded that, although the differences were small (5%) changes in pressure concentration, untrimmed cows stress more the sole lateral as compared to trimmed on the front feet, and on the rear feet, they stress more the heel region whereas trimmed cows tend to have a slight better balance among regions. Conversely, when cows are trimmed, the typical sole lesion spot concentrates more pressure than the heel itself (20.20% versus 16.72% respectively) and may favor the occurrence of sole ulcers.Laminite (manqueira) pode ser associado a fatores mecânicos, causados por falta de balanceamento na distribuição de pressão na sola dos cascos de vacas confinadas em instalações modernas, que utilizam pisos de concreto. No presente estudo, a subdivisão original dos cascos de vacas leiteiras foi modificada para diferenciar-se entre a porção anterior (local típico de lesão) e posterior da sola medial dos cascos, e para enfatizar as pressões máximas aplicadas somente na área de contato não levando em consideração a área total da sola. Os resultados mostraram significância estatística (p < 0.044) para a interação entre Grupo, Pata e Região (G*L*R). Foi observado que a porção posterior (calcanhar) das patas traseiras de vacas não-casqueadas foram estressadas mais intensamente que de vacas casqueadas (23 % versus 16.72% da pressão total aplicada nas patas em não-casqueadas e casqueadas respectivamente). As pressões na região do local típico de lesão aumentaram em animais casqueados comparado com não-casqueados (20.20% versus 15.9%). As patas da frente apresentaram diferenças na concentração de pressão da sola lateral (29% versus 23.25% em não-casqueadas versus casqueadas, respectivamente). Foi concluído que, apesar das diferenças serem pequenas (5%) mudanças nas concentrações de pressão, vacas não-casqueadas estressaram mais a porção da sola lateral, comparado a vacas casqueadas nas patas da frente, enquanto nas traseiras elas estressam mais a região do calcanhar, e as vacas casqueadas tendem a ter uma distribuição melhor de pressão entre as regiões. No entanto, quando as vacas são casqueads, a região típica de lesão tende a concentrar mais pressão do que o próprio calcanhar (20.20% versus 16.72% respectivamente) podendo favorecer a incidência de úlcera de sola

Clinical Study to Assess the Level of Consciousness/General Anesthesia Following the Administration of High Doses of Xylazine Hydrochloride in Cattle

Achieving anesthesia without DEA controlled drugs prior to administration of IV potassium chloride (KCl) is a limiting factor for humane euthanasia. An overdose of xylazine hydrochloride (XH) is thought by some to induce unconsciousness and is commonly administered prior to IV KCl injection. This study’s purpose was to determine the level of unconsciousness achieved from an overdose of XH in cattle

Bacterial Causes of Digital Dermatitis (DD) in Dairy Cattle

Bovine digital dermatitis (DD) is a leading cause of lameness in dairy cattle throughout the world. Despite 35 years of research, the definitive cause of the disease process is still unknown. Previous studies have demonstrated that multiple bacterial species are associated with lesions, with spirochetes being the most reliably identified organism. This study utilized total DNA sequencing of 48 staged DD biopsy specimens collected during a 3-year longitudinal study of disease progression in dairy cattle. Over 175 million sequences were obtained and used to identify the bacterial species that were present in the biopsies. There was no evidence of a fungal or DNA viral causes. The bacterial communities present in the biopsy specimens was found to progress through a systematic series of changes that correlate with the novel visual lesion scoring system developed as part of this project. Although Treponema spp. predominated in the advanced lesions, they were in relatively low abundance in the newly described early lesions that are associated with the initiation of the disease process. The results of this study support the hypothesis that DD is a polybacterial disease process and provide unique insights into the temporal changes in bacterial populations throughout lesion development. These insights are expected to be critical in the development of new treatment strategies and the potential development of effective vaccines. In addition, the development and validation of a lesion scoring system will assist with determining the prognosis of a lesion

A Highly Effective Protocol for the Rapid and Consistent Induction of Digital Dermatitis in Holstein Calves

Bovine Digital Dermatitis (DD) is a leading cause of lameness in dairy cattle. DD is reportedly increasing in prevalence in beef cattle feedlots of the US. The exact etiologic agent(s) responsible for the disease have yet to be determined. Multiple studies have demonstrated the presence of a variety of Treponema spp. within lesions. Attempts to reproduce clinically relevant disease using pure cultures of these organisms has failed to result in lesions that mirror the morphology and severity of naturally occurring lesions. This manuscript details the systematic development of an experimental protocol that reliably induces digital dermatitis lesions on a large enough scale to allow experimental evaluation of treatment and prevention measures. In total, 21 protocols from five experiments were evaluated on their effectiveness in inducing DD lesions in 126 Holstein calves (504 feet). The protocols varied in the type and concentration of inoculum, frequency of inoculation, duration the feet were wrapped, and type of experimental controls need to validate a successful induction. Knowledge gained in the first four experiments resulted in a final protocol capable of inducing DD lesions in 42 of 44 (95%) feet over a 28 day period. All induced lesions were macroscopically and microscopically identified as clinical DD lesions by individuals blinded to protocols. Lesions were also located at the site of inoculation in the palmer aspect of the interdigital space, and induced clinically measurable lameness in a significant portion of the calves. Collectively these results validate the model and provide a rapid and reliable means of inducing DD in large groups of calves