Vaginal temperature and collar activity variations in relation to fecal progestagens of captive moose

Background Timing of reproductive events can be crucial for a species' population growth and stability. Accurate detection of reproductive phenology presents a challenge to scientists studying wild species, including moose (Alces alces). Currently, there are several established methods for monitoring reproductive activity and events in domestic ruminants, including the use of biologging devices. The main objective of this study was to determine whether female moose display a distinct thermal and activity pattern associated with luteal activity during the estrous cycle, which could be used to determine the onset of their breeding season. We deployed biologging devices and collected fecal samples from 12 captive female moose on the Kenai Peninsula, Alaska, USA to explore variation in vaginal temperature and collar activity and the relationship between these variables and fecal progestagen concentrations. Fecal samples were collected from mid-August to mid-October and analyzed using radioimmunoassay to determine the concentration of fecal progestagens to classify luteal activity.Results Captive female moose displayed an identifiable thermal pattern during the onset of luteal activity from mid-September to mid-October, associated with the initial estrous cycle of their breeding season. In contrast, we did not observe a distinct pattern in activity during this period. Recurring patterns in both vaginal temperature and activity were identified between mid-October and mid-November, however, which were likely associated with subsequent estrous cycles but not included in our fecal sampling period.Conclusions This study supports that female moose display an identifiable pattern in vaginal temperature which is associated with luteal activity of the initial estrous cycle of the breeding season. An identifiable pattern was observed for both vaginal temperature and activity registrations at the presumed timing of subsequent estrous cycle of the breeding season

Development and utilization of implantable cardiac monitors in free-ranging American black and Eurasian brown bears: System evolution and lessons learned

Biologgers can be used to monitor both human and animal physiology and behaviors, activity patterns, and/or environmental stressors. Monitoring of heart rates and rhythms, respiratory patterns, and activity in free-ranging bears can provide unique insights into physiological mechanisms. Such research can also influence the conservation of wildlife, the management of human-wildlife conflicts, and potentially human medicine. Here we describe our experiences with the development and utilization of three generations of implantable biologgers in American black and Eurasian brown bears (Ursus americanus and Ursus arctos arctos). These devices have enabled novel investigations into the underlying mechanisms for winter survival, including the discovery of an extreme respiratory sinus arrhythmias that acts to conserve energy while providing adequate circulation to maintain alertness (i.e., "fight or flight" behaviors). Extreme variations in heart rate have also been documented, including a 33.8s asystole and a 261beats/min sinus tachycardia in black bears and a 39.4s asystole and a 240beats/min sinus tachycardia in brown bears. Long-term data recording has also identified annual trends in heart rates and activity in both species. Combining physiological data with concurrent GPS collar locations provided insights into the impacts of human and environmental stressors (hunting, predation by other bears, road crossings, drones), which would not have been apparent through spatial data analysis alone. More recently, short-range wireless telemetry has allowed for real-time streaming of data via telemetry stations placed in remote den locations. Future iterations include transponders for biomonitoring and as an early warning system to aid in the prevention of poaching in free-ranging animals. In this review, we discuss the primary experimental capabilities of the current and next-generation systems. We highlight device evolution in terms of new physiological measurements (e.g., temperature, activity, impedance, posture), increased data storage capacity, improved wireless capabilities, and miniaturization to reduce the invasiveness of implantation procedures. These biologgers are now being applied to other species, and the possibilities seem limitless as technologies continue to advance

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

The cost of research: Lasting effects of capture, surgery and muscle biopsy on brown bear (Ursus arctos) movement and physiology

Animal models are a key component of translational medicine, helping transfer scientific findings into practical applications for human health. A fundamental principle of research ethics involves weighing the benefits of the research to society against the burden imposed on the animals used for scientific purposes. The utilisation of wild animals for research requires evaluation of the effects of capture and invasive sampling. Determining the severity and duration of these interventions on the animal’s physiology and behaviour allows for refining study methodology and for excluding or accounting for biased data. In this study, 39 Scandinavian brown bears (Ursus arctos) captured either while hibernating in winter or via helicopter in summer and that underwent surgery as part of a human health project had their movement, body temperature and timing of onset of hibernation compared with those of 14 control bears that had not been captured during the same period. Bears captured in winter and summer showed decreased movement from den exit until late summer, compared to those in the control group. Bears captured in summer showed reduced movement and body temperature for at least, respectively, 14 and 3 days, with an 11% decrease in hourly distance, compared to pre-capture levels, but did not differ in the timing of hibernation onset. We reveal that brown bear behaviour and physiology can be altered in response to capture and surgery for days to months, postcapture. This has broad implications for the conclusions of wildlife studies that rely upon invasive sampling

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

Chemical capture of free-ranging red deer (Cervus elaphus) with medetomidine-ketamine

Seventeen free-ranging red deer (Cervus elaphus) (12 calves and 5 yearling hinds) were immobilized with a combination of medetomidine hydrochloride (MED) and ketamine hydrochloride (KET) in winter (January-March). Immobilizations were performed with plastic projectile syringes fired from a dart gun. Mean (SD) doses of 0.147 (0.024) mg MED/kg and 2.5 (0.4) mg KET/kg induced recumbency in 5.0 (2.0) minutes in the calves and all of them were completely immobilized. The initial doses in the yearling hinds were 0.099 (0.016) mg MED/kg and 1.9 (0.2) mg KET/kg but three of them required addirional dosing for induction of reliable restraint. The distance covered by the animals between darting and recumbency ranged from 40-250 m for calves and 100-300 m for yearling hinds. The animals were translocated to deer farms for breeding purposes and were given 12.5-25.0 mg of atipamezole hydrochloride before transportation. All animals recovered completely. Haematological and serum biochemical comparisons between free-ranging calves immobilized with medetomidine-ketamine (n=3) and captive unmedicated calves (n=4) showed that chemical capture induce very little stress in red deer

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

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

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