Epidural analgesia in cattle, buffalo, and camels

[Sole abscess (Pododermatitis purulenta superficialis) in a Bactrian camel - diagnosis, treatment, and healing process]

An approximately 14-year-old female Bactrian camel was referred to the University Clinic for Ruminants with left hindlimb lameness of two weeks duration. All findings of the general clinical examination were within normal limits. Orthopedic examination revealed a left supporting limb lameness score of 2 with moderate weight-shifting and reluctance to bear weight on the lateral toe at walk. The camel was sedated (0.24 mg/kg BW xylazine i.m.+1.92 mg/kg BW ketamine i.m., 0.04 mg/kg BW butorphanol) and rolled in lateral recumbency for further investigations. Sonographic examination of the cushion of the left hindlimb revealed an abscess of diameters of 11×2.3 cm impinging both digits between the sole horn and lateral and medial cushions. The abscess was opened under local infiltration anesthesia after a 5×5 cm incision at the central sole area, the abscess capsule removed with a sharp curette and the abscess cavity flushed. The wound was then bandaged. Postoperative treatment consisted of bandage changes every 5-7 days. For these procedures the camel was repeatedly sedated. At the first change the xylazine dosage was the same for surgery, and sequentially the dosage could be reduced (0.20 mg/kg BW i.m.), but finally increased for the last dressing changes (0.22 mg/kg BW i.m.). Ketamine dosages were also reduced slightly throughout the hospitalization period (1.51 mg/kg BW i.m.), enabling a reduction of the recovery period duration. After 6 weeks of regular bandage changes the wound had healed completely with a new horn layer and showing no lameness the camel could be discharged.

Reliability and Validity of UNESP-Botucatu Cattle Pain Scale and Cow Pain Scale in Bos taurus and Bos indicus Bulls to Assess Postoperative Pain of Surgical Orchiectomy

Pain assessment guides decision-making in pain management and improves animal welfare. We aimed to investigate the reliability and validity of the UNESP-Botucatu cattle pain scale (UCAPS) and the cow pain scale (CPS) for postoperative pain assessment in Bos taurus (Angus) and Bos indicus (Nelore) bulls after castration.

METHODS

Ten Nelore and nine Angus bulls were anaesthetised with xylazine-ketamine-diazepam-isoflurane-flunixin meglumine. Three-minute videos were recorded at -48 h, preoperative, after surgery, after rescue analgesia and at 24 h. Two evaluators assessed 95 randomised videos twice one month apart.

RESULTS

There were no significant differences in the pain scores between breeds. Intra and inter-rater reliability varied from good (>0.70) to very good (>0.81) for all scales. The criterion validity showed a strong correlation (0.76-0.78) between the numerical rating scale and VAS versus UCAPS and CPS, and between UCAPS and CPS (0.76). The UCAPS and CPS were responsive; all items and total scores increased after surgery. Both scales were specific (81-85%) and sensitive (82-87%). The cut-off point for rescue analgesia was >4 for UCAPS and >3 for CPS.

CONCLUSIONS

The UCAPS and CPS are valid and reliable to assess postoperative pain in Bos taurus and Bos indicus bulls.

HMH sked rescue system, revised deer sled, and ice fishing sled as humane on-farm handling tools to move nonambulatory grow-finish pigs on a commercial farm

Objective: The objective of this study was to evaluate an HMH sked rescue system, revised deer sled, and ice fishing sled as humane handling tools for moving nonambulatory pigs on a commercial wean-to-finish farm. Materials and methods: Eighteen commercial crossbred pigs received an epidural to induce a nonambulatory state. The HMH sked rescue system, revised deer sled, and ice fishing sled were tested as handling tools by 2 employees for time to place and move the pig, pig vocalization and struggle scores, and tool durability. Results: Time to place the nonambulatory pig from the start pen floor onto the handling tool, time to secure the nonambulatory pig on the handling tool, and total time were not affected by the handling tool (P ≥ .12). There was a trend for time to move the handling tool with the nonambulatory pig from the start to end pen, which included removing the pig from the handling tool and placing them onto the end pen floor (P = .06). The ice fishing sled was the most durable with no creases, rips, or holes. There were no handling tool differences for pig vocalization or struggle scores (P > .10). Changes in pig respiration rate and pig body temperature did not differ between handling tools (P ≥ .71). Implications: Under study conditions, the sked, revised deer sled, and ice fishing sled were all humane tools to move nonambulatory grow-finish pigs. Caretakers need to evaluate the best choice for their farm.

Antinociceptive effect of lidocaine, tramadol, and their combination for lumbosacral epidural analgesia in rabbits undergoing experimental knee surgery

AIM

The current study aimed to evaluate the antinociceptive effect of lidocaine, tramadol, and their combination for lumbosacral epidural analgesia in rabbits undergoing knee surgery.

MATERIALS AND METHODS

This study was performed on 24 male New Zealand white rabbits weighing 2.8 to 3.0 kg and was allocated into three groups. All groups were anaesthetized by intramuscular (IM) injection of 35 mg/kg ketamine and 5 mg/kg xylazine, 0.1 mg/kg butorphanol. Rabbits in Group A received epidural analgesia of 4 mg/kg lidocaine 2%; Group B rabbits received epidural analgesia of 4 mg/kg tramadol 5%, and Group C rabbits received epidural analgesia of a combination of 4 mg/kg lidocaine and 4 mg/kg tramadol. Prior to and during surgery, the following parameters were recorded in a regular pre-set time interval: onset time of analgesia (OT), duration of flaccid paralysis (DFP), duration of analgesia (DA), onset and duration of sensory blockade, onset and duration of motor blockade, heart rate (HR), respiratory rate (RR), and rectal temperature (RT).

RESULTS

The mean OT demonstrated a significant decrease (P < 0.05) in Group C (46.5 ± 1.4 sec) compared to Group A and B (61.0 ± 2.4 and 54.5 ± 3.5 sec), respectively. DFP was significantly lower (P < 0.05) in Group C (35.5 ± 2.9 min) than in Group A and B (17.6 ± 1.4 and 21.8 ± 3.6), respectively. DA showed a significant increase (P < 0.05) in group C (45.8 ± 3.3 min) compared to groups A and B, respectively (23.3 ± 1.1 and 31.5 ± 2.3). Heart rate, RR, and RT significantly decreased in Group C compared to the other groups.

CONCLUSION

According to the current study findings, lumbosacral epidural administration of lidocaine combined with tramadol could be a better choice for potentiating the analgesia than administration of either drug separately and may be safely used in rabbits undergoing knee surgery.

Evaluation of analgesic, sympathetic and motor effects of 1% and 2% lidocaine administered epidurally in dogs undergoing ovariohysterectomy

OBJECTIVE

To compare, versus a control, the sensory, sympathetic and motor blockade of lidocaine 1% and 2% administered epidurally in bitches undergoing ovariohysterectomy.

STUDY DESIGN

Randomized, blinded, controlled clinical trial.

ANIMALS

A total of 24 mixed-breed intact female dogs.

METHODS

All dogs were administered dexmedetomidine, tramadol and meloxicam prior to general anesthesia with midazolam-propofol and isoflurane. Animals were randomly assigned for an epidural injection of lidocaine 1% (0.4 mL kg^-1; group L1), lidocaine 2% (0.4 mL kg^-1; group L2) or no injection (group CONTROL). Heart rate (HR), respiratory rate (f_R), end-tidal partial pressure of carbon dioxide (Pe'CO₂), and invasive systolic (SAP), mean (MAP) and diastolic (DAP) arterial pressures were recorded every 5 minutes. Increases in physiological variables were treated with fentanyl (3 μg kg^-1) intravenously (IV). Phenylephrine (1 μg kg^-1) was administered IV when MAP was <60 mmHg. Postoperative pain [Glasgow Composite Pain Score - Short Form (GCPS-SF)] and return of normal ambulation were recorded at 1, 2, 3, 4 and 6 hours after extubation.

RESULTS

There were no differences over time or among groups for HR, f_R, Pe'CO₂ and SAP. MAP and DAP were lower in epidural groups than in CONTROL (p = 0.0146 and 0.0047, respectively). There was no difference in the use of phenylephrine boluses. More fentanyl was administered in CONTROL than in L1 and L2 (p = 0.011). GCPS-SF was lower for L2 than for CONTROL, and lower in L1 than in both other groups (p = 0.001). Time to ambulation was 2 (1-2) hours in L1 and 3 (2-4) hours in L2 (p = 0.004).

CONCLUSIONS AND CLINICAL RELEVANCE

Epidural administration of lidocaine (0.4 mL kg^-1) reduced fentanyl requirements and lowered MAP and DAP. Time to ambulation decreased and postoperative pain scores were improved by use of 1% lidocaine compared with 2% lidocaine.

Comparative evaluation of electrocardiographic effects of different doses of medetomidine and xylazine in calf-camels (Camelus dromedarius)

This experimental, prospective, randomised, and blinded study aimed to perform comparative evaluation of electrocardiographic (ECG) effects of different doses xylazine and medetomidine in dromedary calves after intravenous (IV) administration. A total of twenty five clinically and paraclinically healthy male dromedary calves aged 15±2 weeks and weighing 95±5.5 kg were assigned randomly to five different groups (four experimental and one control). Groups XL and XH received a low (0.2 mg kg-1) and high (0.4 mg kg-1) dose of xylazine hydrochloride and groups ML and MH received a low (10 µg kg-1) and high (20 µg kg-1) dose of medetomidine hydrochloride once, IV. Finally, the control group (C) received normal saline in the same manner. ECG indices were evaluated on post treatment 0, 5, 10, 15, 30, 60, 90, 120 min, and 24 h. There was no significant difference in heart rate (HR) in all experimental groups at T90. HR was significantly lower after high doses than after low doses of medetomidine and xylazine at T120. HR was significantly lower in XH than in other groups of study at T24. At T90 QRS amplitude in XH was statistically lower than in control and XL groups. Analysis of P wave duration revealed that in MH and XH it was significantly longer than in ML, XL and control at T5. Duration of P wave in control group was significantly shorter than in all experimental groups from T10 to T90. RR interval duration was significantly shorter at T5 and T10 in control group compared to experimental groups. At T120, RR interval duration in MH and XH was considerably longer than that in ML, XL, and control. Compared with control group, cardiac arrhythmia scores were significantly lower than in all experimental groups from T5 to T60. At T90 and T120 in MH and XH, cardiac arrhythmia scores were significantly higher than those of XL, ML, and control. According to our findings, using low dose of medetomidine (10 µg kg-1) and xylazine (0.2 mg kg-1) was suggested in comparison with high dose of medetomidine (20 µg kg-1) and xylazine (0.4 mg kg-1) in dromedary calves with cardiac diseases in the field.

Xylazine Regulates the Release of Glycine and Aspartic Acid in Rat Brain

Introduction

Xylazine, a type of α₂-adrenoceptors, is a commonly used drug in veterinary medicine. Xylazine-induced changes in the content of amino acid neurotransmitters - glycine (Gly) and aspartic acid (Asp), in different brain regions and neurons were studied.

Material and Methods

Wistar rats were administered 50 mg/kg or 70 mg/kg of xylazine by intraperitoneal injection. In addition, in vitro experiments were conducted, in which neurons were treated with 15 μg/mL, 25 μg/mL, 35μg/mL, and 45 μg/mL of xylazine. Test methods were based on the enzyme-linked immunosorbent assays (ELISA).

Results

During anaesthesia, Asp levels in each brain area were significantly lower compared to the control group. Except for the cerebrum, levels of Gly in other brain areas were significantly increased during the anaesthesia period. In vitro, xylazine-related neuron secretion of Gly increased significantly compared to the control group at 60 min and 90 min. Moreover, xylazine caused a significant decrease in the levels of Asp secreted by neurons at 20 min, but gradually returned to the level of the control group.

Conclusion

The data showed that during anaesthesia the overall levels of Asp decreased and overall levels of Gly increased. In addition, the inhibitory effect of xylazine on Asp and the promotion of Gly were dose-dependent. Our data showed that different effects of xylazine on excitatory and inhibitory neurotransmitters provided a theoretical basis for the mechanism of xylazine activity in clinical anaesthesia.

Xylazine regulates the release of glycine and aspartic acid in rat brain

Introduction

Xylazine, a type of α2-adrenoceptors, is a commonly used drug in veterinary medicine. Xylazine-induced changes in the content of amino acid neurotransmitters – glycine (Gly) and aspartic acid (Asp), in different brain regions and neurons were studied.

Material and Methods

Wistar rats were administered 50 mg/kg or 70 mg/kg of xylazine by intraperitoneal injection. In addition, in vitro experiments were conducted, in which neurons were treated with 15 μg/mL, 25 μg/mL, 35μg/mL, and 45 μg/mL of xylazine. Test methods were based on the enzyme-linked immunosorbent assays (ELISA).

Results

During anaesthesia, Asp levels in each brain area were significantly lower compared to the control group. Except for the cerebrum, levels of Gly in other brain areas were significantly increased during the anaesthesia period. In vitro, xylazine-related neuron secretion of Gly increased significantly compared to the control group at 60 min and 90 min. Moreover, xylazine caused a significant decrease in the levels of Asp secreted by neurons at 20 min, but gradually returned to the level of the control group.

Conclusion

The data showed that during anaesthesia the overall levels of Asp decreased and overall levels of Gly increased. In addition, the inhibitory effect of xylazine on Asp and the promotion of Gly were dose-dependent. Our data showed that different effects of xylazine on excitatory and inhibitory neurotransmitters provided a theoretical basis for the mechanism of xylazine activity in clinical anaesthesia.

An Update on Drugs Used for Lumbosacral Epidural Anesthesia and Analgesia in Dogs

This review aims to report an update on drugs administered into the epidural space for anesthesia and analgesia in dogs, describing their potential advantages and disadvantages in the clinical setting. Databases searched include Pubmed, Google scholar, and CAB abstracts. Benefits of administering local anesthetics, opioids, and alpha₂ agonists into the epidural space include the use of lower doses of general anesthetics (anesthetic “sparing” effect), perioperative analgesia, and reduced side effects associated with systemic administration of drugs. However, the potential for cardiorespiratory compromise, neurotoxicity, and other adverse effects should be considered when using the epidural route of administration. When these variables are considered, the epidural technique is useful as a complementary method of anesthesia for preventive and postoperative analgesia and/or as part of a balanced anesthesia technique.