Efficacy of a Lidocaine-Impregnated Elastrator Band for Castration and Tail Docking in Lambs.

The primary objective of this study was to demonstrate the non-inferiority between lidocaine-impregnated ligation bands (LLBs) and control bands (CBs) with respect to the efficacy of castration and tail docking. Secondary objectives were to compare castration and tail-docking success, evaluate local site reactions, and compare average daily gain (ADG) between the treatment groups. A total of 238 male lambs were enrolled and randomly assigned to receive LLBs or CBs on their tail and scrotum. Lambs were weighed, had a health assessment, and the band site was observed on -3, 7, 14, 21, 28, 35, and 42 days after the bands were applied. A linear regression model was built to assess average daily gain, whereas a repeated measures model was used to evaluate body weight differences at each of the measured timepoints. Furthermore, logistic regression models were used to evaluate associations with casting outcomes. Few differences were noted between treatment groups with respect to casting success for the scrotum and tail and ADG over the entire experimental period. Non-inferiority calculations demonstrated no differences in tail docking and scrotal casting success, with casting occurring for the majority of animals by d 21 and d 42 for castration and tail docking, respectively. However, lambs receiving LLBs gained more weight from d -3 to 7 (+0.03 kg/d; 95% CI: 0 to 0.07), which may be an indication of effective pain control during the first week following band application. Overall, the use of an LLB does not affect the time to successful casting of the tail and could improve short-term growth when compared to a control band. Further studies are needed to compare LLBs to multimodal methods of pain relief.

Efficacy and Safety of Lidocam Topical Gel (4% Lidocaine-0.3% Meloxicam) for Pain and Inflammation Management during Castration and Tail Docking in Piglets.

(1) Background: It has been well established that castration and tail docking are both painful during and following the procedure, yet there are limited convenient and effective products to address both short-term and long-term pain. Lidocam Topical Gel (LTG) (4% lidocaine and 0.3% meloxicam) was developed to address industry needs for an effective and safe product to address animal welfare concerns regarding castration and tail docking in piglets. (2) Methods: Study 1: Male piglets aged 4-8 days of age were treated with LTG (n = 30) or a control gel (n = 30). Approximately 30 min after application of the gel, the piglets were surgically castrated and tail docked. The efficacy of pain control during the surgical procedures and post-procedure (24 h) pain and inflammation control were evaluated using both behavioral and physiological measurements. Study 2: Meloxicam residue depletion following LTG treatment was followed for 28 days. Study 3: Clinical and pathological safety were evaluated in five groups of eight piglets receiving LTG with: (1) no treatment, (2) nominal topical dose, (3) two times the nominal topical dose, (4) three times the nominal topical dose, and 5) one times the nominal topical dose and 2 mL of LTG by oral gavage daily for 3 days. (3) Results: LTG-treated piglets had a significant reduction in electrocutaneous stimulation response before the procedures and 4 and 24 h post-procedures. Stress vocalization intensity and duration were less in piglets receiving LTG during the surgical procedures. Plasma cortisol and substance P were significantly lower in LTG-treated piglets 3 h after castration and tail docking. The weight and average daily gain were significantly increased in piglets receiving LTG. LTG did not interfere with wound healing or cause irritation at the application sites. There were no abnormal clinical or pathological findings associated with the use of LTG at three times the nominal dose given daily for three days. As meloxicam persisted in the application site tissue, a slaughter withdrawal time of 24 days was determined. (4) Conclusions: When applied to the skin 30 min before castration and tail docking, LTG is effective in surgical pain control and provides post-surgical pain control for up to 24 h. LTG is safe for use in piglets and provides an acceptable withdrawal time for commercial use. LTG is a potentially effective product for commercial use for piglet castration and tail docking.

Assessment of the Effective Tissue Concentrations of Injectable Lidocaine and a Lidocaine-Impregnated Latex Band for Castration in Calves.

This study aimed to assess the effective tissue concentrations of the current standard of care for pain mitigation in calves during castration (injectable lidocaine) and to assess the ability of a lidocaine-loaded elastration band (LLB) to deliver effective concentrations into the scrotal tissue over time. This study comprised two different trials: (1) effective concentrations of injectable lidocaine in the scrotal tissue; and (2) the in vivo delivery of effective concentrations of lidocaine from LLBs placed on the calf scrotums. Sensation in the scrotal tissue was assessed by electrocutaneous stimulation. Injectable lidocaine allowed for short-term anesthesia for up to 60 min, highlighting the importance of finding additional strategies to mitigate long-term pain. An elastomeric ligation band impregnated with lidocaine could provide a suitable alternative, as it yielded tissue levels of lidocaine that approached EC50 and exceeded EC95 at 2 and 72 h following application, respectively, and remained above those levels for at least 28 days after application. Further studies are warranted to compare the use of LLBs to injectable local anesthetics.

Assessment of the Pharmacokinetics and Pharmacodynamics of Injectable Lidocaine and a Lidocaine-Impregnated Latex Band for Castration and Tail Docking in Lambs.

The objectives of this study were to assess the pharmacokinetics and pharmacodynamics of the current standard-of-care for pain mitigation in lambs during castration and tail docking (injectable lidocaine) and assess the ability of Lidocaine-Loaded Bands (LLBs) to deliver therapeutic concentrations into the contacted tissues over time. The study was comprised of four different trials: (1) investigation of in vitro release of lidocaine from LLBs; (2) pharmacokinetics and pharmacodynamics of injectable lidocaine in scrotal and tail tissue; (3) pharmacokinetics and pharmacodynamics of in vivo delivery of lidocaine with LLBs placed on the tail and scrotum of lambs; and (4) a "proof-of-concept" study comparing the sensation of control- versus LLB-banded tail tissue over time. The use of injectable lidocaine provides effective short-term anesthesia for 120 to 180 min following the injection; however, additional strategies are needed to manage long-term pain. The use of an LLB could provide an alternative where tissue lidocaine concentrations meet or exceed the EC50 for at least 21-28 days and, based on electrostimulation data, provides local anesthesia for at least 3 days when compared to a control band. Further studies are needed to compare the use of an injectable local anesthetic to the LLBs.

Impact of Dystocia on Milk Production, Somatic Cell Count, Reproduction and Culling in Holstein Dairy Cows.

This study investigated the effects of dystocia on milk production, somatic cell count, reproductivity, disease, and milk production. A total of 2159 cows across 21 dairy farms in Alberta, Canada were enrolled in this study. Multivariable models were created to explore associations between outcome variables and calving ease score. In total, 89.5% of calvings were unassisted, 6.1% were an easy pull, and 4.3% were a moderate-hard pull. Cows that had a moderate-hard pull produced 4.01 kg less milk, 0.12 kg less volume of milk fat, and 0.12 kg less milk protein per day than those that had an unassisted calving. No difference was found between calving ease groups with respect to SCC. Cows with a moderate or hard pull produced 510 kg less milk per lactation than unassisted cows. Cows with a moderate to high level of assistance at birth had a higher hazard of being culled over the duration of their lactation. Cows with an easy pull had increased odds of developing a retained placenta. It is evident that assistance at calving, particularly a moderate-hard pull, is associated with significant impacts on future milk production and risk of being culled; therefore, efforts should be made to minimize dystocia and prevent these impacts.

Evaluation of Activated Charcoal as an Alternative to Antimicrobials for the Treatment of Neonatal Calf Diarrhea.

PURPOSE: Neonatal calf diarrhea (NCD) is a major cause of death and economic loss in the cattle industry. Although NCD is caused by a variety of nutritional factors and non-bacterial pathogens, treatment typically includes systemic antimicrobial therapy, even for non-severe cases that are more likely to have non-bacterial causes. Novel, non-antimicrobial therapies are needed to reduce antimicrobial use and optimize production efficiency. METHODS: This production-level study compared the efficacy of activated charcoal to that of an antimicrobial regimen for treating mild-to-moderate cases of NCD, and identified the most common etiological agents. Calves diagnosed with non-severe diarrhea were randomly allocated into 3 treatment groups (n = 86 per group): group A received a standard antimicrobial regimen, B received both antimicrobials and activated charcoal, and C received activated charcoal only. Animals were monitored over the course of 7 days for mortality and recovery from diarrhea. Fecal samples were collected upon enrollment (day 0) and on day 7 to assess the presence of major NCD-causing pathogens. RESULTS: Mortality was higher for groups B and C relative to A, although this difference was only statistically significant for group B vs A. No significant difference in the number of recovered animals was observed among the treatment groups, although group C was significantly slower to recover than A or B. The vast majority of day 0 samples were positive for non-bacterial organisms (mainly rotavirus and Cryptosporidium parvum), which decreased significantly by day 7 regardless of treatment group. CONCLUSION: Antimicrobials only moderately improved outcomes for non-severe diarrhea cases relative to activated charcoal. Thus, systemic antimicrobial treatment is likely unnecessary for the majority of NCD cases and should be limited to severe cases.

Development and Field Validation of Lidocaine-Loaded Castration Bands for Bovine Pain Mitigation.

Castration is among the most common management procedures performed in the dairy and beef cattle industries and is mainly performed by surgery or elastic banding. Despite the various benefits of castration, all methods produce pain and distress. Castration by banding is simple, inexpensive, produces fewer complications, and can be performed in a high-throughput manner. Because lidocaine, a local anesthetic, can be delivered to trauma sites topically, we have formulated lidocaine-loaded castration bands (LLBs) to deliver local pain relief to calves during banded castration. The initial lidocaine content of three band types developed was between 80 and 200 mg per band. The transfer kinetics of lidocaine into tissue was determined in vitro, indicating a rapid release for the first 30 min, followed by a slow release lasting at least 48 h. Furthermore, the lidocaine delivery and pain mitigation effects of these LLBs were compared to standard lidocaine injections in vivo. Field studies indicated that LLBs performed at least as well as lidocaine injections for short-term lidocaine delivery into tissues and pain mitigation. Moreover, LLBs significantly outperformed lidocaine injections for long-term delivery and pain mitigation. The concentrations of lidocaine in the LLB-treated tissue samples were generally in the range of 0.5-3.5 mg of lidocaine per gram of tissue and were overall highest after 6 h. Lidocaine-loaded elastration bands deliver therapeutic quantities of lidocaine into scrotal tissues over a period of at least seven days in cattle. This approach would provide long-term pain mitigation to the animals and, by avoiding surgery or the administration of injections, would also decrease the time and handling costs for the producer.

Comparison of the efficacy of silver-based antimicrobial burn dressings in a porcine model of burn wounds.

PURPOSE: A variety of silver-based antimicrobial dressings are available on the market and are commonly used to prevent infection. Such prophylaxis is particularly important in treating burns, yet there is a paucity of evidence confirming the efficacy of commercially available dressingsin vivo. We describe here an in vivo porcine model of burns, which we use to test the antimicrobial efficacy of three common wound dressings and a control. PROCEDURES: Domestic Yorkshire-cross pigs were medicated for pain management before inflicting burns with a heated brass rod. The wounds were artificially challenged with a mixture of two pathogens commonly associated with burn wound infection:Staphylococcus aureus and Pseudomonas aeruginosa. The following dressing materials were sutured in place: gauze, nanocrystalline silver, silver-plated nylon, and polyethylene/polyester coated with high-oxidation silver salts. After 1 and 3 days, the wounds were assessed for erythema, swelling, and re-epithelialization, tissue was biopsied to determine the recovery of the challenge microorganisms, and histology was performed. We also examined the number of microorganisms present on the dressings themselves. RESULTS: Histology indicated that 30 s was sufficient to produce burns extending into the deep dermal layer. After 3 days, nanocrystalline silver and silver-plated nylon led to slightly reduced swelling relative to simple gauze, although none of the dressings significantly affected erythema or wound re-epithelialization. All the dressings led to decreased recovery of the challenge organisms from the burn tissue, relative to simple gauze. However, the magnitude of the reduction was greatest for nanocrystalline silver (log10 reduction = 4-5); additionally, only nanocrystalline silver gave a statistically significant decrease (P = 0.02). Notably, the antimicrobial effect for all dressings was reduced by Day 3 relative to Day 1. Similar trends were observed for microbial retention on the dressings themselves. CONCLUSION: Nanocrystalline silver-based wound dressings generally outperformed silver-plated nylon and high-oxidation silver salts in thisin vivo model of burn wounds. Relative to prophylactic use, it may be advisable to change the dressings more frequently when treating an infected wound.

Antimicrobial Susceptibility of Bacteria That Cause Bovine Respiratory Disease Complex in Alberta, Canada.

Bovine respiratory disease (BRD) is the most important illness of feedlot cattle. Disease management targets the associated bacterial pathogens, Mannheimia haemolytica, Mycoplasma bovis, Pasteurella multocida, Histophilus somni, and Trueperella pyogenes. We conducted a cross-sectional study to measure the frequencies of antimicrobial-resistant BRD pathogens using a collaborative network of veterinarians, industry, government, and a diagnostic laboratory. Seven private veterinary practices in southern Alberta collected samples from both living and dead BRD-affected animals at commercial feedlots. Susceptibility testing of 745 isolates showed that 100% of the M. haemolytica, M. bovis, P. multocida, and T. pyogenes isolates and 66.7% of the H. somni isolates were resistant to at least one antimicrobial class. Resistance to macrolide antimicrobials (90.2% of all isolates) was notable for their importance to beef production and human medicine. Multidrug resistance (MDR) was high in all target pathogens with 47.2% of the isolates resistant to four or five antimicrobial classes and 24.0% resistance to six to nine classes. We compared the MDR profiles of isolates from two feedlots serviced by different veterinary practices. Differences in the average number of resistant classes were found for M. haemolytica (p < 0.001) and P. multocida (p = 0.002). Compared to previous studies, this study suggests an increasing trend of resistance in BRD pathogens against the antimicrobials used to manage the disease in Alberta. For the veterinary clinician, the results emphasize the importance of ongoing susceptibility testing of BRD pathogens to inform treatment protocols. Surveillance studies that collect additional epidemiological information and manage sampling bias will be necessary to develop strategies to limit the spread of resistance.