Treatment protocols for claw horn lesions and their impact on lameness recovery, pain sensitivity, and lesion severity in moderately lame primiparous dairy cows

This study aims to investigate the effects of routine treatment protocols for claw horn disruptive lesions (CHDL) on lameness recovery rates, pain sensitivity, and lesion severity in moderately lame primiparous cows. A cohort of first parity cows was recruited from a single commercial dairy herd and randomly allocated to five treatments, comprising four lame groups (LTNB, LTN, LTB, and LT) and a single group non-lame group. Eligibility criteria for the lame cows included a first lameness score (score 3/5), presence of CHDL on a single foot, good body condition score of 3.0 to 3.5, and no history of previous lameness. LTNB received a combination of therapeutic trim, administration of a non-steroidal anti-inflammatory drug (NSAID; Ketoprofen) for 3 days, and hoof block on the healthy claw. Both LTN and LTB received the same treatment as LTNB without hoof block and NSAID, respectively. LT received only a therapeutic trim, whereas non-LT (negative control) received either a therapeutic or preventive trim. Pain sensitivity was assessed using the limb withdrawal reflex while lesion severity was recorded using the International Committee Animal Records (ICAR) Atlas guide. The enrolled cows were observed at weekly intervals, and the primary outcomes were assessed 28 days after treatment. The number (%) of recovered cows was 15 of 20 (75%), 13 of 21 (61.9%), 6 of 14 (42.9%), and 6 of 15 (40%) for LTNB, LTN, LTB, and LT, respectively. LTNB had significantly higher odds of successful treatment (OR = 4.5; 95% 1.1-19.1) compared to LT. Pain sensitivity based on limb withdrawal reflex was absent in a significantly higher number of cows (15/20; 75.0%) in LTNB compared to LTB and LT. LTB had a significantly lower lesion severity score in comparison to LTN. Overall, cows with limb withdrawal at day 28 after treatment were less likely (OR = 0.06; 95% CI 0.01-0.24) to develop a non-lame score. In conclusion, the treatment with therapeutic trim, hoof block, and NSAID led to better recovery and reduced pain sensitivity in moderately lame primiparous cows with good BCS compared to those that received only therapeutic trim. Further research on the changes within the hoof capsule following various treatment protocols is needed to elucidate the clinical benefits observed in this study.

Blood calcium dynamics in cows receiving an aqueous calcium suspension for voluntary consumption or a calcium bolus following parturition

The form of oral calcium (Ca) supplement and the Ca source influence Ca absorption dynamics resulting in different postpartum calcemia. The objective of this study was to investigate whether an oral Ca supplement (mainly CaCO3) offered for voluntary consumption would maintain or increase postpartum blood Ca to the same degree as a Ca bolus (mainly CaCl2) providing an equivalent dose of a Ca. A total of 72 Holstein cows were blocked by expected parturition date and parity. Within each block of 3 animals, cows were randomly assigned to one of three treatments, including an oral Ca supplement offered for voluntary consumption (Ca-drink, n = 23), an oral Ca bolus (Ca-bolus, n = 24), or an untreated group (CON, n = 25). Treatments were administered once within 15 min postpartum. The Ca-drink provided 45 g of Ca (CaCO3 source) and was mixed in 20 L of lukewarm water and offered to cows for 30 min. The Ca-bolus provided 43 g of Ca (71% from CaCl2 and 29% from CaSO4) and was administered once. Both Ca-bolus and CON cows received 20-l of lukewarm water at parturition to standardize the volume of fluids (Ca-drink or 20-l lukewarm water) offered at parturition. Dairy cows offered Ca-drink had a 28% higher fluid consumption than Ca-bolus and CON cows. Milk yield and milk composition expressed in percentage protein, fat, lactose, and urea did not differ, whilst there was a small but significant increase in DMI in cows receiving the Ca-drink compared to CON, while Ca-bolus did not differ from other groups. This was consistent with reduced BW losses between week 1 and 3 in cows receiving the Ca-drink suspension. Treatment by time interactions were present for blood Ca, glucose, and urea concentrations. Blood Ca was relatively stable in Ca-drink cows, while higher fluctuations were observed in Ca-bolus cows. In Ca-bolus cows, blood Ca increased from 15 min to 6 h, decreased from 6 to 24 h, and finally increased again from 24 to 48 h. At 24 h post administration, blood Ca was greater in cows receiving the Ca-drink than cows receiving the Ca-bolus. Blood glucose was greater in Ca-bolus cows at 15 min after treatment administration compared with Ca-bolus and CON, while blood urea was higher in CON than Ca-drink and Ca-bolus throughout the sampling period. These results indicate that voluntary oral Ca resulted in a relatively stable calcemia, whereas higher fluctuations were observed in cows receiving the Ca-bolus. Due to a lack of differences between Ca-drink and Ca-bolus compared with CON, it is not possible to conclude regarding the efficacy in maintaining postpartum blood Ca.

Sedation With Xylazine Hydrochloride Decreases the Stress Response in Merino Meat Sheep During Routine Hoof Trimming in a Tilt Table

We hypothesized that the hoof trimming in sheep in dorsal recumbency implicates a short but intensive stress situation and that the sedation with xylazine causes a decrease in the stress response in this situation. Ten healthy female merino meat sheep were randomly divided into two groups receiving either xylazine hydrochloride (0.1 mg/kg body mass (BM) applied intramuscularly) or a placebo treatment with 0.9% NaCl. Routine hoof trimming was performed in a tilt table and vital signs (rectal temperature (RT), heart rate (HR), and respiratory rate (RR)), 33 different behavioral traits and blood cortisol concentrations were recorded throughout the experiment at six different time points (total of 55 min). The procedure itself elicited a clear stress response (increase in the RR, RT, defensive movements, lip twitching, swallowing, and flight behavior). Parallelly, the blood cortisol concentrations were increased, reaching their maximum with 81.5 ng/ml in the control group when the sheep were tilted back into a standing position. In the sedated sheep, no increase in the RR and RT and a decrease in the HR were observed. In addition, the behavioral signs showed a decrease in flight, defensive, and general stress behavior (decrease in licking, movement of head and legs, and sitting on knees), complemented by the serum cortisol concentrations showing 2.28 times reduced concentration at the end of the procedure, compared to the control sheep. The results confirm our hypothesis and support the conduction of future trials investigating the feasibility and benefit of a sedation of sheep prior to routine hoof trimming under practical circumstances.

Development of novel intravenous regional anaesthetic technique for desensitization of hoof in cattle

The cattle having hoof diseases were selected in the study and divided into 2 groups having 6 animals in each group. For induction of intravenous regional anesthesia, tourniquet was placed circumferentially at the metacarpus and just below dewclaw in group 1 and 2, respectively. Mixture of lignocaine and ketamine (L+K) (4 mg/kg and 3 mg/kg b. wt.) was injected in the radial vein in group 1 animals. However, in group 2 animals the dose of L+K was halved (2 mg/kg and 1.5 mg/kg b. wt.) and injected in the dorsal common digital vein III. The anesthetic potency was monitored by observing the HR, PR, RR, systolic pressure, diastolic pressure and SPO2. In group 1 the heart rate decreased significantly at 10 min interval. Peripheral oxygen saturation significantly decreased up to 60 min and 40 minutes in group 1 and 2 animals, respectively. Systolic pressure significantly increased at 60 minute interval in group 1 animals. After removal of tourniquet, systolic pressure and diastolic pressure was significantly increased in group 2. Sensory and motor block onset time was less in group 2 as compared to group 1. Sensory and motor block recovery time was long in group 2 as compared to group 1 animals. It was concluded that novel IVRA technique was more safe as compared to standard IVRA for the hoof anesthesia in cattle because low doses of local anesthetic are required in this technique with early sensory and motor block, and prolonged effect.

Higher odds of abortion in dairy cows hoof trimmed late in gestation

Until now, it is unknown whether hoof trimming late in gestation is associated with increased risk of abortion in dairy cows. Using data from 1,476,013 pregnancies in Danish dairy cows, the objective of the present study was to evaluate risk factors for abortion in cows hoof trimmed during pregnancy. Odds of abortion was lower in first parity cows, lower in Jersey cows compared to other breeds, and higher in cows pregnant with twins. Odds of abortion was 2.4 times higher in cows hoof trimmed within the last four weeks before end of pregnancy. Hoof trimming of cows in late gestation should be done with caution.

Claw Trimming as a Lameness Management Practice and the Association with Welfare and Production in Dairy Cows

Lameness resulting from claw lesions remains a pressing welfare issue in dairy cows. Claw trimming (CT) is a common practice for prevention and management of clinically lame cows. This review summarizes the results of studies that have investigated various claw trimming (CT) methods, their application in lameness management, and associations with the welfare and production of dairy cows. The papers included in this review fulfilled the following inclusion criteria: published in peer review journal or book chapter within the last 20 years (1999-2019), written in English, and focused on the application of CT for lameness management and the association with either welfare or production variables. Databases used included Google scholar, Web of Science and PubMed. A total of 748 records were assessed and 61 papers were eligible for inclusion and the main objectives and results were used to categorize the results under six topics: CT techniques, association between CT and claw overgrowth/specific claw lesions, timing and frequency of CT, association between CT and behavioral variables, association between CT and physiological parameters, and association between CT and production. The literature findings showed the existence of various CT methods with the common types including the Dutch Five-step, White Line, White Line Atlas, and Kansas techniques. There is data paucity on the efficacy of these techniques in lameness management; however, the slight procedural difference yields varying sole thicknesses and presentations which may influence their prophylactic use. Results regarding the impact of CT on welfare and production were discussed in relation to potential short and long-term benefits. Depending on the lesion type and severity level, CT may induce immediate painful sensation, stress, changes in lying down activities and reduction in milk yield, but the positive impacts were more evident at later stages of lactation following improvement in locomotion score. The majority of the reviewed studies were lacking a detailed description of CT techniques and claw health of the studied animals; thus, reducing the strength of demonstrating CT-related benefits. However, electronic recording of claw health data during every CT visit provides the basis for monitoring hoof health and could assist in curtailing some of these challenges. To elucidate CT-related benefits, certain areas requiring further research were highlighted such as ascertaining the appropriate timing for preventive CT and identifying cows that will benefit more from such intervention during lactation.

Dairy Farmers' Perceptions of and Actions in Relation to Lameness Management

Simple Summary

Lameness is a pressing issue in dairy production. Dairy farmers are primarily responsible for the welfare of their cows and decision-making regarding lameness management. However, there are concerns regarding the communication of the importance of lameness to farmers and their motivation towards proper management. A review of the literature indicates that various factors influence farmers’ perceptions about lameness, their adoption of recommended measures and whether or not they end up treating a lame cow. This review summarizes these related issues in consideration of the welfare and economic implications of farmers’ decisions. The information herein is vital to the identification of measures on how to motivate dairy farmers towards appropriate lameness management.

Abstract

Lameness continues to be a welfare and economic issue for dairy cows. However, the consequences of lameness seem to be better understood by veterinarians and related personnel in comparison to dairy farmers. Prompt detection and treatment of lame cows is essential in reducing its negative impact on milk processing systems. To that end, understanding farmers’ perceptions regarding the significance of lameness to dairy cows is vital. One fundamental aspect is the underestimation of lameness prevalence by dairy farmers, which is as a result of different understanding of the problem. The same applies to their decision to treat lame cows and to adopt various detection and management practices. All of these shortcomings contribute to poor cattle welfare and economic losses in dairy production. This review summarizes the results of studies that have investigated dairy farmers’ perceptions of lameness and the associated implications on the wellbeing and productivity of dairy cows. Factors associated with farmers’ attitudes toward claw health and lameness management are also presented. Additionally, economic observations relating to lameness prevention, treatment and the adoption of lameness detection systems are also highlighted. To strengthen these points, interventional programmes requiring farmers’ participation are discussed as a promising approach in answering some of these challenges. A review of the literature indicates both the opportunities and barriers inherent in the tackling the lameness issue from the farmers’ perspectives. Such knowledge is crucial in identifying measures on how to motivate dairy farmers towards proper lameness management.

New Treatment for Urethral Rent in Stallions

The aim of this report is to describe a new methodology to successfully treat stallions diagnosed with urethral rent. Four stallions of ages ranging from 7 to 12 years (median 9) with hemospermia were admitted for clinical evaluation, breeding soundness examination, and urethroscopy for inspection of the urethra and vesicular glands. Once the presence of urethral rent was identified and/or other sources of hemorrhage were excluded, a topical treatment was performed with 4% Policresulen solution (Albocresil). The treatment was carried out by infusing 100 mL of the solution into the lumen of the urethra through a catheter placed up to the region of the ischial arch. This procedure was repeated once daily, or at 48 hours intervals, resulting in a total of 4-7 infusions. In all cases, chemical cauterization was efficient in the healing of the urethral rent. However, due to masturbation during treatment, one animal did not completely heal, and the treatment with the Policresulen was prolonged. It is believed that the low pH of the solution resulted in urethritis, which was treated with systemic therapy of antibiotic and anti-inflammatory nonsteroidal. Topical treatment with 4% Policresulen was found to be efficient in the chemical cauterization of urethral rent in stallions. This treatment was efficient, practical, less invasive, and less costly than the alternative of surgical methods, which are more invasive and require longer recovery time of the animal. However, sexual rest and the elimination of sexual stimuli from the environment are essential management in association with this therapeutic method.

An Update on the Assessment and Management of Pain Associated with Lameness in Cattle

Lameness affects the cattle industry via both economic losses and welfare considerations. In addition to production deficits, the pain and distress associated with lameness have been documented. Evaluation and prevalence of lame cattle are among the primary factors in third-party welfare audit programs. Mean lameness prevalence in herds has been reported to be as high as 36.8%, although a less than 10% prevalence of lame cattle was reported by some producers. Note that lameness is usually underreported by producers compared with independent observers, potentially because of a decreased sensitivity in detecting lame cattle.

Evaluation of intravenous regional anaesthesia and four-point nerve block efficacy in the distal hind limb of dairy cows

Background

Intravenous regional anaesthesia (IVRA) and hindfoot four-point nerve block anaesthesia (NBA) are recommended for local anaesthesia (LA) in the distal limb of dairy cows. Two studies were conducted to compare the efficacy, time until onset and stress responses to IVRA and NBA in dairy cows. In the first cross-over designed study, eight healthy unsedated German Holstein cows, restrained in lateral recumbency (LR) on a surgical tipping table, were treated with IVRA and NBA using procaine 2% as a local anaesthetic. Distal limb desensitization was tested by electrical (e-), mechanical (m-) and thermal (t-) nociceptive stimulation 10 min before and 15 and 30 min after LA. Hormonal-metabolic (blood concentrations of cortisol, lactate, non-esterified fatty acids, and glucose) and cardio-respiratory (heart and respiratory rate, mean arterial blood pressure) stress responses to treatment were assessed at predetermined intervals. In the second study, six healthy, unsedated German Holstein cows in LR were treated (crossover design) with IVRA and NBA. Short-interval e-stimulation was measured by the time until complete distal limb desensitization.

Results

In the first study, four of eight cows responded to e-stimulation 15 min after IVRA, while none of the cows treated with NBA responded until the safety cut-off level was reached. E-stimulation revealed complete desensitization of the distal limb 30 min after LA in all cows. Half of the cows did not respond to m- and t-stimulation before LA, so no further evaluation was performed. Stress reactions to IVRA and NBA treatment were similar, but differences may have been masked by stress response to LR restraint. In the second study, complete desensitization was achieved 12.5 min after NBA, while one of the six cows still responded to e-stimulation 20 min after IVRA.

Conclusion

Hindfoot nerve block anaesthesia and intravenous regional anaesthesia induced complete desensitization of the distal hind limb in dairy cows. However, the anaesthesia onset after NBA was significantly faster than that of IVRA, which may be clinically relevant in the field, particularly when distal limb anaesthesia is required for major claw surgeries under time constraints.