Immobilization of free-ranging moose (Alces alces) with medetomidine-ketamine and remobilization with atipamezole

Seventeen free-ranging moose {Alces alces) (2 adult males, 13 adult females and 2 female calves) were immobilized with a combination of medetomidine hydochloride (MED) and ketamine hydrochloride (KET) in early autumn (August-September). Drugs were administrated with plastic projectile syringes fired from a dart gun, either from a car or by approaching the animals on foot. MED at 30 mg/adult and 15 mg/calf in combination with KET at 400 mg/adult and 200 mg/calf induced complete immobilization with sternal or lateral recumbency and loss of the corneal reflex in all individuals. The mean ± SD time from darting to when the animals were found was 18.3 ± 8.7 min for adults and the mean distance covered by these animals between darting and recumbency was 320 + 200 m. No side effects of clinical significance were detected and registration of the rectal temperature (38.8 ± 0.5°C), heart rate (44 ± 7 beats/min), respiratory rate (31 ±20 breaths/min) and relative arterial oxygen saturation (89 ± 3 %, n=8) during immobilization in adults showed that these physiological parameters were within the safe ranges established for moose. Blood samples from adults were analyzed for 17 haematological and 33 serum biochemical constituents and the results were compared to corresponding values found in moose immobilized with etorphine (ETO). Although the lower levels (p<0.05) found for haematocrit, red blood cells, haemoglobin and Cortisol in the MED-KET group may indicate a difference in the stress response, the low muscle enzyme levels in both groups show that these immobilizing drugs and capture methods induce very little physical stress in moose. A hyperglycaemic response was found in MED-KET treated animals. Atipamezole hydrochloride (ATI) rapidly remobilized all animals and the time elapsing from ATI administration to standing was 3-9 ± 1.8 min after i.v./s.c. treatment (n=7) and 6.9 ± 3.4 min after i.m./s.c. injection (n=8). No side effects were detected after reversal. In conclusion, medetomidine-ketamine and atipamezole can be recommended for reversible immobilization of free-ranging moose in early autumn

Effects of medetomidine and atipamezole on serum glucose and cortisol levels in captive reindeer (Rangifer tarandus tarandus)

Serum concentrations of glucose and Cortisol were measured in five adult captive reindeer (Rangifer tarandus tarandus) at 24 h and 10 min before, and at 0.5, 1,2,4, 8, 12 and 24 h after, treatment with 60 p.g/kg of medetomidine i.v. followed by 300 jig/kg of atipamezole i.v. 60 min later. The experiments were performed in January and repeated in July-August. The animals were used as their own controls and treated with saline in July-August. The wash-out period between experiments in summer was 2 weeks or more. No obvious seasonal differences were observed. Mederomidine induced a 2.5-fold increase in glucose (mean ± standard error of the mean being 15.4 ± 0.6 mmol/1 at 1 h) and a 3.5-fold increase Cortisol (349 ± 28 nmol/1 at 0.5 h). Serum glucose reached control levels within 12 h, and Cortisol declined to baseline levels within 4 h after injection og medetomidine. The use of blood concentrations of glucose and Cortisol to assess nutritonal status, body condition and stress may be significantly biased in animals chemically immobilized with medetomidine or other alpha-2 adrenoceptor agonists

Lead contamination in Australian game meat

Lead-based ammunition (gunshot and bullets) frequently leaves small lead fragments embedded in the meat of wild-shot game animals. Australia produces several commercial game meat products from wild animals harvested with lead-based ammunition and has a growing population of recreational hunters. However, no studies have previously investigated the frequency of lead fragments or lead concentrations in Australian game meat. We examined 133 Australian minced game meat items of four types for evidence of lead contamination. Samples were meat from kangaroos (Macropus and Osphranter spp.; n=36) and Bennett's wallabies (Notamacropus rufogriseus; n=28) sold for human consumption, and deer ('venison'; multiple spp.; n=32) and stubble quail (Coturnix pectoralis; n=37) harvested for private consumption by recreational hunters. All packages were studied by digital radiography to detect the presence of radio-dense fragments, assumed to be lead fragments from ammunition. Visible fragments were absent in commercially available kangaroo products, but were present in 4%, 28% and 35% of wallaby, venison and quail, respectively. Mean meat lead concentrations (mg/kg wet weight) were 0.01 +/- 0.01 for kangaroo, 0.02 +/- 0.01 for wallaby, 0.12 +/- 0.07 for venison, and 1.76 +/- 3.76 for quail. The Australian food standards threshold for livestock meat (0.1 mg/kg w.w.) was not exceeded by any kangaroo or wallaby products but was exceeded by 53% and 86% of venison and quail, respectively. Radiography only detected 35% of samples that were above the food safety threshold. While average lead concentrations in commercially available macropod (kangaroo and wallaby) meat were low, those in recreationally harvested game meat may pose health risks for hunters and associated consumers

Haematological and serum biochemical reference values in free-ranging red deer (Cervus elaphus atlanticus)

Analyses of haematological and biochemical constituents were carried out on the Norwegian subspecies of free-ranging red deer (Cervus elaphus atlanticus). All animals were captured from January to March by using a mixture of xylazine and tiletamin-zolazepam. Immobilisation was performed with plastic projectile syringes fired from a dart gun. Fourteen haematological parameters were analysed. There were no differences in the values between hinds and stags and between adults and calves (P > 0.01). Of the 22 biochemical compounds investigated there was a significant difference (P < 0.01) between calves and adults for lactate dehydrogenase (LD), globulin, beta globulin, gamma globulin, and the minerals Na, K, Mg, Zn, Ca, and P. Differences (P < 0.01) between hinds and stags were found in cholesterol, gamma glutamyl transferase (GGT), alpha-1 globulin, alpha-2 globulin and Cu. The blood values determined in this study can be used as reference values for this red deer subspecies immobilised with a mixture of xylazine-tiletamin-zolazepam for health control and diagnosis of diseases.Abstract in Norwegian /Sammendrag:Hematologiske og biokjemiske parametere er analysert på norsk frittlevende hjort (Cervus elaphus atlanticus). Hjorten ble immobilisert i tidsrommet januar til mars ved hjelp av et spesialgevær ladet med plast kanyler som inneholdt en blanding av xylazin og tiletamin-zolazepam. Det var ingen forskjeller i de14 undersøkte hematologiske verdiene mellom hinder, kalver og bukker (P>0,01). Av de 22 biokjemiske parametrene som ble undersøkt var det en signifikant forskjell mellom kalver og voksne (P<0,01) når det gjelder laktat dehydrogenase, globulin, beta globulin, gamma globulin og mineralene Na, K, Mg, Zn, Ca og P. Det var en signifikant forskjell mellom hinder og bukker (P<0.01) på parametrene kolesterol, gamma glutamyl transferase, alfa-1 globulin, alfa-2 globulin og Cu. Blodverdiene som ble målt i dette studiet kan bli brukt som referanseverdier for norsk hjort som er immobilisert med blandingen xylazin-tiletamin-zolazepam for helsekontroll og for diagnostisering av sykdommer

Body temperature patterns during pregnancy and parturition in moose

Gestation and lactation have high energetic requirements. Up to three-fourths of the gestation period in moose (Alces alces) overlaps with the food-scarce period in winter. During this period, moose deal with the limited forage resources available through hypometabolism with decreased heart rate and body temperature (Tb). Body temperature is also an indicator of oestrus, pregnancy and parturition, which is well documented in several domestic species. In this study, we sought to determine if moose displayed a similar Tb pattern during pregnancy and parturition to domesticated ruminants, and if we could detect parturition by combining Tb and activity data. We studied the Tb pattern of 30 free-ranging adult female moose (>= 1.5 years old), equipped with ruminal temperature loggers and GPS collars. We documented a 0.13-0.19 degrees C higher Tb in pregnant compared to non-pregnant moose, depending on the study area with the Tb difference increasing along a south-north gradient, and a drop in Tb and in activity when parturition was imminent. Detection of parturition was highly successful when combining Tb and activity data with an accuracy of 91.5%. Our findings demonstrate that Tb responses to pregnancy and parturition in a wild capital-breeding ruminant are similar to those of domesticated ruminants

A comparison of lead-based and lead-free bullets for shooting sambar deer (Cervus unicolor) in Australia

Context: In response to the toxic health threats posed by lead (Pb), there is currently a focus on transitioning to lead-free bullets for shooting wild animals. Aim: We aimed to quantify the killing efficiency and animal welfare outcomes of lead-based and lead-free (copper-based) bullets for ground-based shooting of sambar deer (Cervus unicolor) in Victoria, south-eastern Australia. Methods: We used shooter-collected data from recreational diurnal hunting and professional nocturnal culling during 2020–2021. Shooters recorded rifle calibre, cartridge type, bullet mass, bullet type, shooting outcomes (miss, wound or kill), shooting distance, flight distance (the distance between where the animal was shot and where it died) as an assumed positive correlate of time to incapacitation, anatomical zones struck by bullets, and frequency of bullet exit wounds. We used flight distance as our response variable, assuming that it is positively correlated with time to incapacitation. To examine the role of several predictor variables (including bullet type) potentially influencing flight distance, the dataset was reduced to those deer killed with a single thoracic shot. Key results: Our data captured shooting events involving 276 deer, with 124 deer shot at with lead-based bullets and 152 with copper-based bullets. Most (87%) of the deer were killed with a single shot. The frequency of non-fatal wounding was <4% for both bullet types and there was no distinct difference in the probability of a single shot kill for deer shot with either bullet type. For those deer killed with a single thoracic shot (n = 198), there was no evidence that bullet energy or shooting distance influenced flight distance. After accounting for differences in terminal kinetic energy, the mean flight distance of deer shot with lead-free bullets (35 m) was 56% greater than that of deer shot with lead-based bullets (22 m). Conclusions: Lead-based and lead-free bullets produced similar animal welfare outcomes for shooting sambar deer. Implications: A transition to lead-free ammunition for shooting sambar deer would have minimal impact on efficiency or animal welfare outcomes

Retention and loss of PIT tags and surgically implanted devices in the Eurasian beaver

Background Passive integrated transponder devices (PIT tags) are a valuable tool for individual identification of animals. Similarly, the surgical implantation of transmitters and bio-loggers can provide useful data on animal location, physiology and behavior. However, to avoid unnecessary recapture and related stress of study animals, PIT tags and bio-loggers should function reliably for long periods of time. Here, we evaluated the retention of PIT tags, and of very high frequency (VHF) transmitters and bio-loggers that were either implanted subcutaneously or into the peritoneal cavity of Eurasian beavers (Castor fiber). Results Over a 21-year period, we implanted PIT tags in 456 individuals and failed to detect a PIT tag at recapture in 30 cases, consisting of 26 individuals (6% of individuals). In all instances, we were still able to identify the individual due to the presence of unique ear tag numbers and tail scars. Moreover, we implanted 6 VHFs, 36 body temperature loggers and 21 heart rate loggers in 28 individuals, and experienced frequent loss of temperature loggers (at least 6 of 23 recaptured beavers) and heart rate loggers (10 of 18 recaptured beavers). No VHFs were lost in 2 recaptured beavers. Conclusions Possible causes for PIT tag loss (or non-detection) were incorrect implantation, migration of the tag within the body, a foreign body reaction leading to ejection, or malfunctioning of the tag. We speculate that logger loss was related to a foreign body reaction, and that loggers were either rejected through the incision wound or, in the case of temperature loggers, possibly adhered and encapsulated to intestines, and then engulfed by the gastro-intestinal tract and ejected. We discuss animal welfare implications and give recommendations for future studies implanting bio-loggers into wildlife

Arterial oxygenation and acid-base status before and during oxygen supplementation in captive European bison (Bison bonasus) immobilized with etorphine-acepromazine-xylazine

Chemical immobilization of captive European bison (Bison bonasus) is often required for veterinary care, transportation, or husbandry practices playing an important role in conservation breeding and reintroduction of the species. We evaluated the efficiency and physiological effects of an etorphine-acepromazine-xylazine combination with supplemental oxygen in 39 captive European bison. Animals were darted with a combination of 1.4 mg of etorphine, 4.5 mg of acepromazine, and 20 mg of xylazine per 100 kg based on estimated body mass. Arterial blood was sampled on average 20 min after recumbency and again 19 min later and analyzed immediately with a portable i-STAT analyzer. Simultaneously, heart rate, respiratory rate, and rectal temperature were recorded. Intranasal oxygen was started after the first sampling at a flow rate of 10 mL.kg(-1).min(-1) of estimated body mass until the end of the procedure. The initial mean partial pressure of oxygen (PaO2) was 49.7 mmHg with 32 out of 35 sampled bison presenting with hypoxemia. We observed decreased respiratory rates and pH and mild hypercapnia consistent with a mild respiratory acidosis. After oxygen supplementation hypoxemia was resolved in 21 out of 32 bison, but respiratory acidosis was accentuated. Bison immobilized with a lower initial drug dose required supplementary injections during the procedure. We observed that lower mean rectal temperatures during the immobilization event were significantly associated with longer recovery times. For three bison, minor regurgitation was documented. No mortality or morbidity related to the immobilizations were reported for at least 2 months following the procedure. Based on our findings, we recommend a dose of 0.015 mg.kg(-1) etorphine, 0.049 mg.kg(-1) acepromazine, and 0.22 mg.kg(-1) xylazine. This dose reduced the need for supplemental injections to obtain a sufficient level of immobilization for routine management and husbandry procedures in captive European bison. Nevertheless, this drug combination is associated with development of marked hypoxemia, mild respiratory acidosis, and a small risk of regurgitation. Oxygen supplementation is strongly recommended when using this protocol

Thermal and behavioural responses of moose to chemical immobilisation from a helicopter

Instrumentation and sample collection for wildlife research and management may require chemical immobilisation of animals, which may entail physiological and behavioural effects on them. It is therefore important to evaluate the immobilisation protocols to reduce the risk of mortality and morbidity of the handled animals and their populations. Using a multi-sensor approach, we assessed the short-term (< 10 days) thermal and behavioural responses of 10 adult female moose (Alces alces) equipped with ruminal temperature loggers and GPS collars with accelerometers to helicopter-based chemical immobilisations. We investigated the body temperature (T-b), movement rates, and resting time before, during, and after recapture. Chemical immobilisations on average increased maximum T-b by 0.71 degrees C during the capture day, and imposed longer travel distances during the capture day and the two following days (3.8 and 1.8 km, respectively), compared to a 10-day reference period before the immobilisation. The probability of resting was 5-6% lower on the capture day and the two following days compared to the reference period, and females with offspring had a higher probability of resting than females without. Maximum T-b, movement rate, and resting time returned to pre-capture levels on an individual level 2 h, 3 days, and 3 days after the immobilisation, respectively. Chemical immobilisation of moose from a helicopter increases the energy expenditure deduced through movement and T-b rise lasting for hours to days. Ecological and physiological studies aimed at inferring general patterns may encounter bias if including sensor and tracking data from tagged animals without accounting for potential post-capture effects