Yohimbine antagonizes the anaesthetic effects of ketamine-xylazine in captive Indian wild felids

Living on the sea-coast: ranging and habitat distribution of Asiatic lions

Endangered Asiatic lions (Panthera leo persica) are renowned for their resilience and as a flagship of successful conservation and management. Lions dispersing out of the Gir forest have established themselves in the coastal habitats for about 25 years. We propose that the home range and spatial distribution of lions inhabiting the coastal habitats would be distinct from the forested habitats of the protected area. Each individual was monitored for an average of 367.2 ± 99.05 days from 2019 to 2021. The mean core area was 33.8 km² (50% FK, SE 8.7 km²) and the overall average range was 171.8 km² (90% FK, SE 40.5 km²). The home ranges were significantly larger for lions residing in the coastal area compared to lions in the protected area. The lion distribution model was built on MaxEnt, and inputs included location fixes of lions and variables, including 18 land use categories and Euclidean distance to linear infrastructures and human settlements. Lions were shown to use forest habitat patches extensively, followed by available habitats around water sources and wasteland. The study highlights the importance of corridors connecting to the Gir protected area and the importance of coastal forest patches for lion conservation and management.

Successful rescue, medical management, rehabilitation, and translocation of a Red Panda Ailurus fulgens (Mammalia: Carnivora: Ailuridae) in Arunachal Pradesh, India

We document the rescue of a Red Panda from Yachuli circle, Lower Subansiri district and successful translocation to Eaglenest Wildlife Sanctuary, West Kameng district of Arunachal Pradesh, India. The head injury was surgically managed under the anaesthetic combination of ketamine and xylazine, and reversed with yohimbine. The animal was successfully rehabilitated and translocated in the Eaglenest Wildlife Sanctuary.

Dexmedetomidine and ketamine simultaneous administration in tigers (Panthera tigris): pharmacokinetics and clinical effects

Background

The study determines the pharmacokinetic profiles of dexmedetomidine (DEX), ketamine (KET) and its active metabolite, norketamine (NORKET), after simultaneous administration. Moreover, the study evaluates the sedative effects of this protocol, its influence on the main physiological variables and the occurrence of adverse effects.

Methods

Eighteen captive tigers were initially administered with a mixture of DEX (10 µg/kg) and KET (2 mg/kg) by remote intramuscular injection. In case of individual and specific needs, the protocol was modified and tigers could receive general anaesthesia, propofol or additional doses of DEX and KET.

Results

Based on the immobilisation protocol, nine animals were assigned to the standard protocol group and the other nine to the non-standard protocol group. Higher area under the first moment curve (AUMC_0-last) and longer mean residence time (MRT_0-last) (P<0.05) were observed in the non-standard protocol group for DEX, KET and NORKET, and higher area under the concentration-time curve from administration to the last measurable concentration (AUC_0-last) only for KET. The KET metabolisation rate was similar (P=0.296) between groups. No differences between groups were detected in terms of stages of sedation and recoveries. All physiological variables remained within normality ranges during the whole observation period. During the hospitalisation period, no severe adverse reactions and signs of resedation were observed.

Conclusion

The simultaneous administration of 10 µg/kg of DEX and 2 mg/kg of KET can be considered an effective protocol for chemical immobilisation of captive tigers, along with dosage adjusments or when other drugs are needed.

Efeitos cardiovasculares da medetomidina e cetamina em Puma concolor e tempo de recuperação após aplicação de ioimbina ou atipamezole

RESUMO O objetivo deste estudo foi avaliar as alterações cardiorrespiratórias causadas pela medetomidina associada à cetamina, e o tempo de recuperação após aplicação intramuscular de atipamezole ou ioimbina em Puma concolor. Para isso, foi realizada a aplicação de medetomidina (100µg/kg) associada à cetamina (5mg/kg) em 11 onças-pardas, sendo os parâmetros cardiorrespiratórios registrados a cada 15 minutos, durante 90 minutos de avaliação. Em seguida, a anestesia foi revertida com aplicação intramuscular de ioimbina (0,4mg/kg; n=5) ou atipamezole (0,25mg/kg; n=6), sendo analisado o tempo até a recuperação. Dos parâmetros cardiorrespiratórios avaliados, houve diferença apenas na frequência respiratória (entre os momentos 60 e 90 minutos), estando esta, todavia, dentro do intervalo de referência para a espécie. Além disso, verificou-se tempo para decúbito esternal significativamente menor nos animais do grupo atipamezole (18±7 minutos), quando comparado ao grupo ioimbina (36±17 minutos), entretanto o tempo de recuperação completa foi estatisticamente igual entre os dois reversores analisados. Assim, a associação anestésica promoveu anestesia eficiente, segura e de rápida indução em onças-pardas, permitindo a imobilização dos animais durante os 90 minutos de avaliação, sem a ocorrência de complicações. Ao se comparar a reversão anestésica com atipamezole e ioimbina, observou-se equivalência dos fármacos no tempo de recuperação completa dos animais.

Physiological and biochemical variables in captive tigers (Panthera tigris) immobilised with dexmedetomidine and ketamine or dexmedetomidine, midazolam and ketamine

Physiological and biochemical variables in captive tigers (Panthera tigris) immobilised with dexmedetomidine and ketamine or dexmedetomidine, midazolam and ketamine were evaluated. Thirty tigers received either dexmedetomidine (0.025 mg/kg) and ketamine (3 mg/kg) (group DK) or dexmedetomidine (0.0125 mg/kg), midazolam (0.1 mg/kg) and ketamine (3 mg/kg) (group DMK). Heart rate, SPO2 and blood pressure were measured at five-minute intervals. Arterial pH, PO2, PCO2, glucose, K+ and arterial and venous lactate were measured at 15 and 45 minutes after immobilisation. A generalised linear mixed model was used for statistical comparison. There was no difference within or between groups at any time point for any measured variable. Measured PO2 was 73.2±17.5 mm Hg and SPO2 was 88.9±10.8 per cent. Systolic, mean and diastolic blood pressures were 170.5±48.4, 138.9±41.8 and 121.8±37.2 mm Hg, respectively. Venous lactate was higher than arterial lactate within groups at each time point. Seizure-like behaviour was observed in 25 per cent of tigers in group DK but not in group DMK. The addition of midazolam into a protocol for immobilisation of tigers did not result in a difference in any of the measured variables but may have prevented the development of seizure-like behaviour.

Use of xylazine hydrochloride-ketamine hydrochloride for immobilization of wild leopards (Panthera pardus fusca) in emergency situations

In India, leopards (Panthera pardus fusca) inhabit human-dominated landscapes, resulting in encounters that require interventions to prevent harm to people, as well as the leopards. Immobilization is a prerequisite for any such intervention. Such emergency field immobilizations have to be carried out with limited tools, often amidst large uncontrollable crowds. An effective and practicable approach is discussed, based on 55 wild leopard immobilizations undertaken between January 2003 and April 2008. A xylazine hydrochloride (1.4 +/- 0.3 mg/kg)--ketamine hydrochloride (5 +/- 2 mg/kg) mixture was used for immobilization of leopards, based on estimated body weight. When weight could not be estimated, a standard initial dose of 50 mg of xylazine--150 mg of ketamine was used. Supplemental doses (50-75 mg) of only ketamine were used as required. No life-threatening adverse effects of immobilization were documented for at least 1 mo postimmobilization.

Ejaculate characteristics, short-term semen storage and successful artificial insemination following synchronisation of oestrus in the Indian blackbuck antelope (Antilope cervicapra)

The blackbuck (Antilope cervicapra) is a small (20–30 kg) Indian antelope that is listed on Schedule I of the Indian Wildlife Protection Act, 1972. Studies were undertaken to develop assisted reproductive technologies, such as synchronisation of oestrus and non-surgical AI, to support the conservation and genetic management of this Indian antelope. Semen characteristics, testosterone levels and the feasibility of short-term cold storage of semen were investigated. Furthermore, different oestrous synchronisation protocols (norgestomet implants and prostaglandin injections) were evaluated for successful AI, defined as the birth of live young. Norgestomet ear implants and i.m. administration of pregnant mare’s serum gonadotropin (PMSG) resulted in successful pregnancies in two of five inseminated females, but both had twin pregnancies that were delivered prematurely. In contrast, two injections of prostaglandin 11 days apart were effective in synchronising oestrus in the blackbuck. Transcervical AI in oestrous-synchronised animals 72 and 96 h after the second prostaglandin injection resulted in successful pregnancies in four of six inseminated females (67%) and resulted in the delivery of three live fawns. These studies demonstrate the potential application of AI technology for the conservation of endangered ungulates. To our knowledge, this is the first report regarding the synchronisation of oestrus and successful non-surgical AI in blackbuck.