Comparison of analgesic techniques for antler removal in halothane-anaesthetized red deer (Cervus elaphus): electroencephalographic responses

OBJECTIVE: To provide evidence for an analgesic effect of antler pedicle compression or lidocaine 'ring block' by comparing changes in median and spectral edge frequencies and total electroencephalographic (EEG) power during the application of each technique followed by antler removal. ANIMALS: Twenty-nine 2-year-old red deer (Cervus elaphus) stags weighing 106-131 kg each were used in this study. Stags were carrying immature growing antler suitable for commercial harvest. MATERIALS AND METHODS: Anaesthesia was induced using propofol (8.25 +/- 1.28 mg kg(-1)) and ketamine (2.18 +/- 0.15 mg kg(-1)) and maintained with halothane in oxygen. End-tidal halothane (Fe'HAL), expired CO(2) tension (Pe'CO(2)), SpO(2), EEG, ECG, and direct arterial blood pressures were recorded continuously. Respiratory rate and somatic responses were recorded at specific time points. After stabilization of anaesthesia (Fe'HAL was approximately 0.8%) baseline data were recorded. Stags were randomly allocated to one of three treatment groups; control, local anaesthesia, or compression band. One antler was removed 4 minutes after the application of treatment. Electroencephalographic responses to application of treatment and antler removal were analysed using area under the curve (AUC) analysis. Mean AUC was compared between groups using anova, and when significant differences were found, groups were compared post hoc with two-tailed t-tests. Significance levels were set at p 相似文献   

Comparison of analgesic techniques for antler removal in halothane-anaesthetized red deer (Cervus elaphus): cardiovascular and somatic responses

OBJECTIVE: To compare changes in heart rate and arterial pressures resulting from compression of the antler pedicle or lidocaine 'ring block' and during subsequent antler removal during minimal halothane anaesthesia. ANIMALS: Twenty-nine 2-year-old red deer (Cervus elaphus) stags, weighing 106-131 kg and carrying immature growing antler suitable for commercial harvest were studied. MATERIALS AND METHODS: Anaesthesia was induced using intravenous propofol (median dose 8.0 mg kg(-1), range 5.2-11.0) and ketamine (median dose 2.2 mg kg(-1), range 1.9-2.4) and maintained using halothane in oxygen. End-tidal halothane concentration (Fe'HAL) end-tidal CO(2) tension (Pe'CO(2)), SpO(2), EEG, ECG, and direct systolic (SAP) mean (MAP) and diastolic (DAP) arterial pressures were recorded continuously. Respiratory rate and somatic responses were recorded. Baseline data were recorded once anaesthesia (Fe'HAL approximately 0.8%) was stable. Stags were randomly allocated to control, lidocaine 'ring block' or compression band treatment groups. One antler was removed 4 minutes after treatment. Cardiovascular responses to the application of analgesia and antler removal were analysed using a general estimates equation for repeated measures or area under the curve (AUC) analysis. Mean AUC was compared between groups using anova, and when significant differences were found, groups were compared post hoc with two-tailed t-tests. Somatic response data were compared with Fisher's exact chi-square test. A value of p < 0.05 was considered significant. RESULTS: Heart rate fell during observations in all groups with no significant differences between groups. Arterial pressures in the control and lidocaine groups during treatment and removal were not different from baseline values or from each other. Compression group pressures were significantly higher than baseline during both treatment and removal. Compression group DAP and MAP were significantly higher after antler removal than during treatment. In control and lidocaine groups, the AUC for SAP, DAP, and MAP over the combined baseline, treatment, and removal period did not differ. The compression group AUC for DAP and MAP were significantly greater over the experimental period than both the lidocaine group and control groups. Somatic responses occurred in one animal at lidocaine injection and three at compression application. Somatic responses occurred in eight control animals and two in the compression group at antler removal. More animals responded to antler removal in the control group than in the compression (p = 0.015) or lidocaine (p < 0.001) groups. CONCLUSIONS: Compression of the antler pedicle appears to be noxious. Pedicular compression is a less effective analgesic technique for antler removal compared to 'ring blocks' with lidocaine. CLINICAL RELEVANCE: This study suggests that lidocaine 'ring blocks' are the current technique of choice for antler removal in deer.     

Behavioural and heart rate responses to velvet antler removal in red deer

Heart rate and behaviour during and following velvet antler removal were monitored in yearling red deer stags to determine the extent to which this procedure was perceived by the deer to be aversive. Nine stags normally kept at pasture were habituated over 5 weeks to the following daily handling procedure. Each deer was fitted with a harness containing a heart rate monitor. It was then allowed to run through a fixed course in a deer yard, restrained for 40 s in a mechanical deer crush, and then confined for 3.5 h with the remainder of the group of stags in an indoor pen containing food and water. In Week 6, the deer were subjected to either restraint for 6 minutes (the control treatment) or removal of one velvet antler under local anaesthesia. Each velvet antler was removed on separate occasions, either on Days 1 and 2 (five deer) or Days 3 and 4 (four deer). The control treatment was applied to all deer when velvet antler was not being removed, and on Day 5. Heart rate and behaviour (time taken to enter the treatment area, and number of struggles made during restraint) were measured before and during treatment, and post-treatment activities were recorded at 0, 1 and 3 h (indoors), and at 6 and 9 h (at pasture). Heart rate was higher during the second velvet antler removal treatment than during the first, but lower during the second control treatment than the first (P<0.05). During velvet antler removal, stags struggled more, and after the treatment flicked their ears, shook their heads, and groomed themselves more than control stags (P<0.05). Stags whose velvet antler had been removed spent less time eating than control stags, and spent progressively more time sitting during the 3.5 h of confinement (P<0.05). However, during the paddock observation at 9 h post-treatment, stags which had had their velvet antler removed grazed more than control stags (P<0.05). The increase in heart rate over the two velvet antler removal treatments and the greater amount of struggling during velvet antler removal indicated that it was more aversive than the control treatment. Post-treatment differences in behaviour may have been due to pain following velvet antler removal.     

Comparison of analgesic techniques for antler removal in wapiti.

The purpose of this research was to compare the effectiveness of ring block anesthesia (LA) and electroanesthesia (A) for antler removal in elk given a long-acting tranquilizer to remove stress from restraint. Thirty-two male wapiti were given 1 mg/kg body weight of zuclopenthixol acetate; the next day, they were restrained in a hydraulic chute, provided with electroanesthesia or a lidocaine ring block, and had their antlers removed. Behavioral response to antler removal was scored. Significantly more (P = 0.032) animals responded to antler removal in the EA group. Heart rates and arterial pressures were measured by a catheter connected to a physiological monitor. Heart rate increased significantly over time with EA, but not with LA. Heart rate increased from baseline significantly more in the EA group immediately prior to antler removal (P = 0.017), immediately post antler removal (P = 0.001), and at 1 min post antler removal (P = 0.037). It was concluded that EA is not as effective a method of anesthesia as is LA for antler removal.     

Routes and doses of lignocaine hydrochloride for analgesia of the velvet antler of stags

AIM: To evaluate the effectiveness of various routes of administration and doses of local anaesthetic to provide analgesia of the velvet antler of young stags. METHODS: In study 1, in which an electrical stimulus was used, 64 l-year-old male red and red X wapiti deer with velvet antler lo-30 cm long, were randomly allocated to one of ten treatments with four treatments/animal, and 23 or 24 antlers/treatment. Treatments delivered included three control groups, three local anaesthetic (2% lignocaine HCL) doses delivered by ring block (5, 10 or 15 ml per pedicle), and a high or low regional block with or without an auriculopalpebral nerve block (5 ml per site). An electrical stimulus was applied before and 1,2,4 and 8 minutes after local anaesthetic treatments and to controls, at an increasing voltage until a response was observed. The voltage and animal responses were recorded. In Study 2 the same seven local anaesthetic treatments (16-I 8 antlers/treatment) were evaluated using 58 of the stags from Study 1 when antlers were ready for removal, but a saw cut was used as the test stimulus. A test cut was applied to the antler I,2 and 4 minutes after application of local anaesthetic. If no response was observed, the antler was removed at that time. RESULTS: In Study 1, major dose and treatment effects were significantly different (p < 0.05) with the outcome variable being whether or not the deer responded. No stags given the high dose ring block responded to electrical stimulation 1 minute after treatment, one responded at 2 minutes, and none responded at 4 or 8 minutes. At least one animal responded after all other treatments at all time intervals. More deer responded after the low regional block than the high regional block, and there was a lower response rate when the auriculopalpebral nerves were anaesthetised. In Study 2, no deer responded 2 minutes after the medium dose ring block treatment. Three of 18 stags receiving the high dose ring block still responded after 2 minutes, and one responded after 4 minutes. Responses occurred to all other treatments at each time, with some deer requiring further administration of local anaesthetic before antler removal, even with the four minute waiting period. CONCLUSION: Ring blocks produced more consistent analgesia of the velvet antler than regional nerve blocks. The high dose ring block produced analgesia faster and more effectively than lower doses, and the regional nerve blocks were more effective when the auriculopalpebral nerve was blocked.     

Behaviour of red deer following antler removal with two methods of analgesia

This study examined the effect of two different methods of analgesia on behavioural responses to velvet antler removal in red deer. Specifically, behaviour during the first 7 h after antler removal using compression (C, latex band around the pedicle) or lignocaine (L, 2% lignocaine hydrochloride) analgesia was compared with controls (R, restraint only).

The frequencies of ear flicking, tongue flicking, yawning, head shaking, grooming and scratching were all higher following antler removal (C + L) than restraint only (P < 0.05). The only overall difference between analgesia methods was for head rubbing which was higher after antler removal with L than with C (P = 0.05). There were differences between compression and lignocaine in the hourly pattern of behavioural changes following antler removal. On an hourly basis, ear flicking was higher in C than L at hour two (P = 0.006) then higher in L than C at hours six and seven (P < 0.01). Tongue flicking was higher in C than L at hour one (P < 0.05). Grooming and yawning were higher in L than C at hour one (P < 0.05) and head rubbing was higher in L than C at hour six (P < 0.01). Agonistic behaviour was higher in R at hour three (P < 0.05). There were no differences in scratching, standing, walking, stepping, running, eating and lying between groups, however; all showed a time trend (P < 0.01). Eating peaked at 3 h, lying showed the main increase throughout the period, although there was also an increase in running in the last 2 h. Panting, standing, stepping and walking all decreased with time.

In summary, behavioural indications of pain or irritation increased following antler removal with analgesia and had mostly disappeared by 7 h. The hourly pattern of behavioural changes following antler removal indicate differences in the time course of pain or irritation between methods of analgesia. Overall behavioural differences between animals receiving either compression or lignocaine analgesia provide little evidence for a difference in post-surgical welfare between these two methods.     

Welfare of farmed deer in New Zealand. 2. Velvet antler removal

This paper reviews published data on welfare aspects of stag restraint and velvet antler removal, and prevention of antler growth. Several studies of physical restraint and handling demonstrate behavioural and physiological changes both during and after velvet antler removal. Interpretations vary as to whether the act of velvet antler removal imposes a welfare cost additional to that of handling and restraint alone. Chemical restraint presents immediate and delayed welfare risks to the animal. Surgical removal of velvet antler can be achieved without acute pain using a high dose rate of local anaesthetic applied as a ring block, rather than as regional nerve blocks, provided the wait time is adequate. However, there is evidence of less than optimum reproducibility. Lignocaine hydrochloride produces rapid analgesia of short duration, whilst bupivacaine has a delayed onset, but longer duration of analgesia. Mepivacaine has a rapid onset and intermediate duration of analgesia. Mixtures of long and short-acting local anaesthetics provide rapid onset and long duration of analgesia. Present methods for electronic analgesia are aversive and not sufficiently effective. The efficacy and possible aversiveness of compression techniques for inducing analgesia of antlers are currently under evaluation. Post-operative pain and the need for its control have been insufficiently researched. Post-operative sequelae are uncommon, but include clostridial infection. Antler growth in most stags can be prevented by rubber-band application to the growing pedicle, although behavioural changes after ring application suggest this practice may be painful. The procedures used for velvet antler removal, and whether practices are acceptable on the balance of welfare costs and benefits, should be reviewed on an ongoing basis as science, using an increasing range of techniques and measures, provides more data about the welfare implications of this practice.     

Xylazine and a xylazine/fentanyl citrate/azaperone combination in farmed deer. II: velvet antler removal and reversal combinations

Three studies were undertaken on farmed red and red x wapiti deer to evaluate xylazine and a xylazine/fentanyl citrate/azaperone combination for velvet antler removal. In the first experiment, 30 1-2 year-old red and 25% red x wapiti deer whose velvet was to be removed were given either 5% xylazine alone at 0.5 mg/kg body weight intramuscularly or the same dose rate of a commercially available mixture of 5% xylazine with the addition of 0.4 mg of fentanyl citrate and 3.2 mg of azaperone per ml. Physiological, behavioural and analgesic responses and reversal times after yohimbine or yohimbine and naloxone were monitored. There were no differences in heart rate, respiration rate, sedative or analgesic properties detected between xylazine or the xylazine/fentanyl citrate/azaperone combination. All deer became recumbent, but those given the xylazine/fentanyl citrate/azaperone combination became recumbent more rapidly than those given xylazine alone (9.4 and 12.5 minutes, respectively, p<0.05). The arousal pattern and timing of reversal of xylazine and xylazine/fentanyl citrate/azaperone using yohimbine and yohimbine and naloxone, respectively, were similar. The second experiment evaluated the reversal of the xylazine/fentanyl citrate/azaperone combination with either yohimbine or yohimbine and naloxone in 43 3-year-old red deer stags after velvet antler removal. There were no differences in arousal pattern or time to standing between reversal treatments. Sixteen 1-year-old red and 25% red x wapiti stags were used in the third experiment to evaluate clinically the analgesic properties of xylazine and xylazine/fentanyl citrate/azaperone combination during velvet removal without the application of a local anaesthetic agent. Withdrawal responses were observed in most deer after the xylazine/fentanyl citrate/azaperone combination at dosages containing 0.5, 0.7 and 0.75 mg of xylazine/kg and after xylazine alone at 0.7 mg/kg, indicating that insufficient analgesia was provided by the systemic agent for the surgical procedure of velvet antler removal. These studies have shown that the knock-down effect of the xylazine/fentanyl citrate/azaperone combination was more rapid than that of xylazine alone, but that other physiological, behavioural and analgesic responses at doses used and evaluated by the methods used were similar. Reversal of both the xylazine and xylazine/fentanyl citrate/azaperone combination was similar when using either yohimbine alone for xylazine and the xylazine/fentanyl citrate/azaperone combination or yohimbine and naloxone for the xylazine/fentanyl citrate/azaperone combination. The evaluation of surgical analgesia for antler removal suggested that both xylazine alone and the xylazine/fentanyl citrate/azaperone combination provided insufficient analgesia and that local anaesthetic should be used in all cases.     

Evaluation of techniques for lignocaine hydrochloride analgesia of the velvet antler of adult stags

AIM: To evaluate the effectiveness of various routes of administration and doses of local anaesthetic (LA) to provide analgesia of the velvet antler of adult stags. METHODS: In Experiment 1, antlers from 50 red deer stags, >or=2-years-old were allocated to 1 of 4 treatment groups (n = 25 antlers/group) to receive injections with 2% lignocaine hydrochloride as follows: High-dose (1 ml/cm pedicle circumference) or Low-dose ring-block (0.4 ml/cm pedicle circumference) or; High-site or Low-site regional nerve block (5 ml per site, both of which included the auriculopalpebral nerve). An electrical stimulus was applied before application of LA and then each min for up to 4 min after LA injection. If no response was observed, analgesia was tested with a saw cut. If no response occurred, the antler was cut at that time. If the animal responded, a further wait time was applied until 4 min had elapsed, at which time observations ceased. In Experiment 2, 10 primary and 50 re-growth antlers were given a High-dose ring-block and tested with a saw cut after 1 min (n = 30) or 2 min (n = 30). If no response occurred, the antler was removed. If a response occurred, further 1-min wait periods were applied. RESULTS: In the High-dose ring-block and High-site nerve-block groups, 24/25 and 21/25 antlers were removed without response by 2 min, compared with 20/25 and 15/25 antlers in the Low-dose ring-block and Low-site nerve-block groups, respectively. The High-dose ring-block provided more effective analgesia after 3 min than the Low-dose ring-block, as assessed by the number of stags that did not respond to the electrical stimulus (p = 0.008), or subsequent antler removal (p = 0.050). The numbers of antlers removed without response after 1 or 2 min were greater using the High-site nerve-block than the Low-site nerve-block (p = 0.002 and p = 0.037, respectively). In all but the High-dose ring-block group, at least 1 stag required further LA after 4 min, before antler could be humanely removed. In Experiment 2, stags reacted to a saw-cut test on 6/30 antlers, 1 min after a High-dose ring-block, compared with 1/30 antlers after 2 min (p = 0.051). CONCLUSION: The High-dose ring-block produced the most effective and rapid analgesia. CLINICAL RELEVANCE: A High-dose ring-block with a 2-min wait period should be the preferred method for achieving local analgesia for velvet antler removal.     

Infectious keratoconjunctivitis in goats

AIMS: To compare two methods of applying rubber rings to the pedicles of yearling stags to induce analgesia in the antler prior to removal. To compare the application of a rubber ring with that of a lignocaine ring block of the antler pedicle on the efficacy and time course of the analgesia produced in yearling stags.

METHODS: Rubber rings were applied to the pedicles of 36 yearling stags that required velvet antler removal. The standard method, a doubled-over ring expanded and lowered down from the distal end of the antler and released midway down the pedicle, was compared with a cable-tie method on the other pedicle, where a ring was pulled around the pedicle by an electrical cable tie threaded through the ring. Brief electrical stimulation (train-of-four mode) was applied proximal and distal to the ring before, and at regular intervals for 1 hour after, application of the ring to a level that produced an auriculopalpebral reflex response.

In a second experiment, each pair of antlers per yearling stag (n=36) was allocated to one of three pairs of treatments, viz no treatment (control) and the cable-tie method as described above, control and local anaesthesia (a ring block of 2 ml 2% lignocaine per cm pedicle circumference), or the cable-tie method and local anaesthesia. Electrical stimulation (tetanic mode) was applied to each antler approximately 25 mm distal to the pedicle/antler junction before, and at intervals up to 1 hour after, application of treatments at a level required to produce a head/neck avoidance behavioural response.

In a third experiment, the two electrical stimulation protocols used above were directly compared by measuring the response of stags (n=8) to one protocol on each pedicle/antler prior to, and at intervals for 1 hour after, application of a rubber ring. At the end of each treatment in all three experiments, analgesia of the antler was established as a nil behavioural response of the stag to a saw cut to the antler (the ‘nick test’).

RESULTS: For both methods of application of a ring the minimum electrical stimulation required distal to the ring to elicit a reflex response increased from around 16 to 55 mA by 60 minutes. In contrast, the electrical stimulation required proximal to the ring remained low (~17.0 mA) throughout. No stag subjected to either of the methods of application responded to the nick test 60 minutes after application of the ring.

The electrical stimulation required to produce a behavioural response increased very rapidly in stags treated with local anaesthetic and at a slower rate in those treated with the cabletie method but showed no significant increase in control stags. After 4 and 30 minutes, for local anaesthesia and the cable-tie method, respectively, 95% of stags were not responding to 80 mA. A significantly greater proportion of stags with antlers treated with local anaesthetic and the cable-tie method did not respond to the nick test than controls, and there was no significant difference in the frequency of the response between stags with treated antlers.

The minimum current required to produce a response proximal to a rubber ring was slightly higher on average for train-of-four electrical stimulus (mean 18.1 (SD 2.6) mA) than for the tetanic mode (mean 11.9 (SD 2.5) mA). The increase in minimum current required to produce the respective response to stimulation distal to the ring was similar for both methods, although the maximum predicted value (67.4 mA) was lower for train-of-four than for the tetanic mode (84.5 mA). No stag responded to the nick test =60 minutes after application of the ring.

CONCLUSIONS: The cable-tie method was no different from the standard method as a procedure for producing analgesia in the antlers of yearling stags and should be accepted as an appropriate procedure for applying analgesic rings to yearling stags. The analgesia produced in the antlers of yearling stags by rubber rings applied by the cable-tie method to the pedicle was similar to that of a lignocaine ring block, but the time course for the development of analgesia was markedly different. Given that a lignocaine ring block is accepted as an adequate method of pain relief for antler removal, the application of rubber rings followed by a period of =30 minutes after application can be advocated as a viable alternative for pain relief.     

Evaluation of techniques for lignocaine hydrochloride analgesia of the velvet antler of adult stags

Aim: To evaluate the effectiveness of various routes of administration and doses of local anaesthetic (LA) to provide analgesia of the velvet antler of adult stags.

Methods: In Experiment 1, antlers from 50 red deer stags, ≥2-years-old were allocated to 1 of 4 treatment groups (n = 25 antlers/group) to receive injections with 2% lignocaine hydrochloride as follows: High-dose (1 ml/cm pedicle circumference) or Low-dose ring-block (0.4 ml/cm pedicle circumference) or; High-site or Low-site regional nerve block (5 ml per site, both of which included the auriculopalpebral nerve). An electrical stimulus was applied before application of LA and then each min for up to 4 min after LA injection. If no response was observed, analgesia was tested with a saw cut. If no response occurred, the antler was cut at that time. If the animal responded, a further wait time was applied until 4 min had elapsed, at which time observations ceased. In Experiment 2, 10 primary and 50 re-growth antlers were given a High-dose ring-block and tested with a saw cut after 1 min (n = 30) or 2 min (n = 30). If no response occurred, the antler was removed. If a response occurred, further 1-min wait periods were applied.

Results: In the High-dose ring-block and High-site nerve-block groups, 24/25 and 21/25 antlers were removed without response by 2 min, compared with 20/25 and 15/25 antlers in the Low-dose ring-block and Low-site nerve-block groups, respectively. The High-dose ring-block provided more effective analgesia after 3 min than the Low-dose ringblock, as assessed by the number of stags that did not respond to the electrical stimulus (p = 0.008), or subsequent antler removal (p = 0.050). The numbers of antlers removed without response after 1 or 2 min were greater using the High-site nerve-block than the Low-site nerve-block (p = 0.002 and p = 0.037, respectively). In all but the High-dose ring-block group, at least 1 stag required further LA after 4 min, before antler could be humanely removed. In Experiment 2, stags reacted to a saw-cut test on 6/30 antlers, 1 min after a High-dose ring-block, compared with 1/30 antlers after 2 min (p = 0.051).

Conclusion: The High-dose ring-block produced the most effective and rapid analgesia.

Clinical relevance: A High-dose ring-block with a 2-min wait period should be the preferred method for achieving local analgesia for velvet antler removal.     

Trial of an inactivated vaccine against egg drop syndrome 76 in New Zealand

There is a legal requirement to provide analgesia for velvet antler removal in New Zealand. Currently, this is achieved using local anaesthetic blockade, with or without systemically administered sedative/analgesic agents, or by compression in 1-year-old stags. Lignocaine hydrochloride 2% is most commonly used and is most effective when administered as a high-dose ring block. Combinations of various amino-amide local anaesthetic agents can achieve rapid onset and prolonged duration of analgesia, though concerns about drug residues and carcinogenic potential of a lignocaine metabolite have led to consideration of the amino-ester family of local anaesthetics as alternatives.

Systemically administered analgesics, including opioids, α2-adrenergic agents and ketamine provide dose-dependent sedation and analgesia. However, none are sufficient, alone or in combination, to produce surgical analgesia at currently recommended dose rates and when reversal agents are given, analgesic effects are usually reversed as well as sedation. Thus, local anaesthetic blockade is still indicated, though the potential for drug or drug-metabolite residues in velvet antler remains a concern.

The need for and effectiveness of non-steroidal anti-inflammatory drugs (NSAIDs) for post-operative analgesia requires investigation. Amitriptyline, locally administered K-opioid agonists, tramadol and other systemically administered agents may warrant future investigation for surgical and post-operative analgesia for velvet antler removal.     

Chemical analgesia for velvet antler removal in deer

There is a legal requirement to provide analgesia for velvet antler removal in New Zealand. Currently, this is achieved using local anaesthetic blockade, with or without systemically administered sedative/analgesic agents, or by compression in 1-year-old stags. Lignocaine hydrochloride 2% is most commonly used and is most effective when administered as a high-dose ring block. Combinations of various amino-amide local anaesthetic agents can achieve rapid onset and prolonged duration of analgesia, though concerns about drug residues and carcinogenic potential of a lignocaine metabolite have led to consideration of the amino-ester family of local anaesthetics as alternatives. Systemically administered analgesics, including opioids, alpha-2-adrenergic agents and ketamine provide dose-dependent sedation and analgesia. However, none are sufficient, alone or in combination, to produce surgical analgesia at currently recommended dose rates and when reversal agents are given, analgesic effects are usually reversed as well as sedation. Thus, local anaesthetic blockade is still indicated, though the potential for drug or drug-metabolite residues in velvet antler remains a concern. The need for and effectiveness of non-steroidal anti-inflammatory drugs (NSAIDs) for post-operative analgesia requires investigation. Amitriptyline, locally administered opioid agonists, tramadol and other systemically administered agents may warrant future investigation for surgical and post-operative analgesia for velvet antler removal.     

Copper supplementation, velvet antler production and growth of rising 2-year-old red deer stags

AIMS: To investigate whether copper supplementation to rising 2-year-old red deer stags (Cervus elaphus) in winter and/or spring improved velvet antler weight, grade and financial value, and liveweight gain. METHODS: Rising 2-year-old red deer stags (n=142) on a commercial deer farm in Hawke's Bay were allocated to two groups on May 14, 1996. One group received 20 g boluses of copper-oxide wire particles. On August 15 each group was reallocated in a crossover design, each sub-group receiving either the same copper-oxide treatment or no treatment, to produce control, winter-only, winter-plus-spring, and spring-only copper treatment groups. Blood samples were collected for serum ferroxidase measurements from seven deer per group and all deer were weighed at 4-6-week intervals. Dates of antler casting and velvet removal, and velvet antler weight and grade were recorded, and the financial value of velvet calculated. Livers from a sample of deer slaughtered at the end of the trial mid-December were analysed to determine copper content. RESULTS: Supplementation with copper did not significantly alter velvet antler weight, daily velvet antler growth rate, days from casting to removal, grade or value, or stag liveweight gain. Serum ferroxidase concentrations averaged 10.0-23.7 IU/l in control deer. Copper supplementation increased mean serum ferroxidase concentrations by approximately 10 IU/l. Mean liver copper concentration in control deer was 99 micromol/kg and ranged from 194 to 386 micromol/kg in the three treated groups. CONCLUSION: Group mean serum ferroxidase concentrations of 10 IU/l and above are adequate for optimum velvet production and liveweight gain in rising 2-year-old stags.     

TMEM219基因可变剪切体相对表达量及其对鹿茸重量的影响

试验旨在研究TMEM219基因3种剪切体在不同重量鹿茸尖端的表达规律及TMEM219基因表达对鹿茸重量的影响,以期探究TMEM219基因对鹿茸生长发育的调控机理。利用实时荧光定量PCR技术对TMEM219基因及其3种剪切体在同一重量组鹿茸的不同组织及不同重量组鹿茸的同一组织mRNA的相对表达水平进行检测,同时测定并比较不同产茸量梅花鹿的血清中胰岛素生长因子1（IGF-1）和胰岛素样生长因子结合蛋白3（IGFBP-3）的浓度。结果表明,TMEM219基因的3种剪接体在梅花鹿鹿茸的间充质及前成软骨组织（RP）、过渡组织（TZ）及软骨组织（C）中均有表达,TMEM219-918基因相对表达量极显著高于TMEM219-1005与TMEM219-1960基因（P<0.01）,TMEM219-1005与TMEM219-1960基因相对表达量无显著差异（P>0.05）;高重量组TMEM219基因表达量显著高于低重量组（P<0.05）;同时,高重量组个体血清中IGF-1浓度显著高于低重量组个体（P<0.05）,而IGFBP-3浓度显著低于低重量组个体（P<0.05）。结果提示,TMEM219基因高表达可能会促进鹿茸的生长,增加鹿茸重量;推测其可能的机理是TMEM219竞争性结合IGFBP-3,减少与其结合的IGF-1,加强IGF-1与IGF-1R的亲和力,进而提高IGF-1对鹿茸生长的促进作用。TMEM219基因可能成为影响鹿茸生长发育的候选基因,为提高鹿茸生长提供理论基础。     

梅花鹿三杈茸、二杠茸、角盘中钙、磷含量比较

为探讨梅花鹿茸内在指标性成分 ,于 2 0 0 0～ 2 0 0 1年对吉林省 11个国营鹿场人工饲养的梅花鹿三杈茸、二杠茸及其角盘中钙、磷含量进行了对比分析。结果表明 ,二杠茸钙、磷含量及钙磷之和均略高于三杈茸 ,分别为 7 32 % (Ca)、6 0 9% (P)及 13 4 1% (Ca +P) ;7 0 6 % (Ca)、5 76 % (P)及 12 82 % (Ca +P) ,二杠茸钙、磷以及钙磷之和的比较差异均不显著 (P >0 0 5 ) ,而鹿角盘中的钙、磷及钙磷之和分别为 7 71% (Ca)、7 4 7%(P)及 15 18% ,明显高于二杠茸和三杈茸 (P <0 0 5 )。     

Pharmacokinetics of articaine hydrochloride and its metabolite articainic acid after subcutaneous administration in red deer (Cervus elaphus)

AIM: To develop and validate a simple and sensitive method using liquid chromatography-mass spectrometry (LC-MS) for quantification of articaine, and its major metabolite articainic acid, in plasma of red deer (Cervus elaphus), and to investigate the pharmacokinetics of articaine hydrochloride and articainic acid in red deer following S/C administration of articaine hydrochloride as a complete ring block around the antler pedicle.

METHODS: The LC-MS method was validated by determining linearity, sensitivity, recovery, carry-over and repeatability. Articaine hydrochloride (40?mg/mL) was administered S/C to six healthy male red deer, at a dose of 1?mL/cm of pedicle circumference, as a complete ring block around the base of each antler. Blood samples were collected at various times over the following 12 hours. Concentrations in plasma of articaine and articainic acid were quantified using the validated LC-MS method. Pharmacokinetic parameters of articaine and articainic acid were estimated using non-compartmental analysis.

RESULTS: Calibration curves were linear for both articaine and articainic acid. The limits of quantifications for articaine and articainic acid were 5 and 10?ng/mL, respectively. Extraction recoveries were >72% for articaine and >68% for articainic acid. After S/C administration as a ring block around the base of each antler, mean maximum concentrations in plasma (C_max) of articaine were 1,013.9 (SD 510.1) ng/mL, detected at 0.17 (SD 0.00) hours, and the C_max for articainic acid was 762.6 (SD 95.4) ng/mL at 0.50 (SD 0.00) hours. The elimination half-lives of articaine hydrochloride and articainic acid were 1.12 (SD 0.17) and 0.90 (SD 0.07) hours, respectively.

CONCLUSIONS AND CLINICAL RELEVANCE: The LC-MS method used for the quantification of articaine and its metabolite articainic acid in the plasma of red deer was simple, accurate and sensitive. Articaine hydrochloride was rapidly absorbed, hydrolysed to its inactive metabolite articainic acid, and eliminated following S/C administration as a ring block in red deer. These favourable pharmacokinetic properties suggest that articaine hydrochloride should be tested for efficacy as a local anaesthetic in red deer for removal of velvet antlers. Further studies to evaluate the safety and residues of articaine hydrochloride and articainic acid are required before articaine can be recommended for use as a local anaesthetic for this purpose.     

外源褪黑素对鹿茸软骨细胞生长发育的影响

试验旨在探讨褪黑素对体外培养的鹿茸软骨细胞增殖、周期及凋亡的影响。利用甲苯胺蓝、茜素红S、阿利新蓝染色鉴定软骨细胞,采用外源添加褪黑素的方法,用不同浓度（0、400、800、1 200、1 600和2 000 pg/mL）、不同时间（24、48和72 h）处理鹿茸软骨细胞,CCK-8法检测细胞增殖。选取800 pg/mL褪黑素处理软骨细胞24 h,利用流式细胞仪检测细胞周期的分布及细胞凋亡情况,采用ELISA试剂盒检测细胞培养液中睾酮含量。结果显示,经不同浓度的褪黑素处理鹿茸软骨细胞不同时间后,800 pg/mL褪黑素处理鹿茸软骨细胞24 h细胞活力极显著增加（P<0.01）。软骨细胞经褪黑素处理后,与对照组相比,褪黑素处理组细胞G1期比例显著降低（P<0.05）;G2期比例极显著增加（P<0.01）,细胞被阻滞在G2期;褪黑素处理组细胞早期凋亡率无显著变化（P>0.05）,晚期凋亡率显著下降（P<0.05）;ELISA检测睾酮分泌水平均显著上升（P<0.05）。综上,外源添加800 pg/mL褪黑素可以促进鹿茸软骨细胞的增殖,抑制软骨细胞的晚期凋亡,促进睾酮的分泌;以上结果可为阐明褪黑素参与鹿茸生长发育机制提供参考。     

鹿茸Ca^2＋含量与塔里木马鹿收茸期的关系研究

为了确定不同年龄段塔里木马鹿鹿茸的最佳收茸时间,保证鹿茸的药用价值,试验选取老、中、青3个年龄段的塔里木马鹿各6头,采用火焰原子吸收分光光度法,分别测定不同生茸时期鹿茸中Ca2＋的含量。结果表明：青年组至6月17日鹿茸上段Ca2＋含量增加显著,确定其最佳收茸时间以6月17日为宜;中年、老年组的最佳收茸时期在6月3日左右,三者存在时间差异。     

梅花鹿锯茸时出血特点及止血药物的研究

为达到更好的锯茸止血效果,对梅花鹿锯茸时出血特点及锯茸止血药物应用效果进行了观察:收取初角茸时呈渗出状出血;收取二杠茸时呈线状出血;收取三杈茸和畸型茸时呈喷射状出血,并且有节律地进行搏动。出血量随着鹿茸的产量和茸根围度的增加而增多,但是当收取茸根围度为(20.3±0.6)cm的畸型茸时却不存在这种明显的相关关系。同一茸型不同年龄的鹿,因茸重、茸根围度的不同出血亦有差别。根据鹿茸的组织结构、生长规律和梅花鹿生理特点,选用由中药组成的外用锯茸止血药方剂,通过锯茸止血试验,结果表明,该锯茸止血药无刺激性,止血快,抗感染能力强,创面愈合良好,对再生茸产量没有明显影响(P>0.05)。