Wild animals are more often immobilized for a variety of reasons, including rou tine health check-ups (veterinary care, surgical intervention, vaccination, hormon al implantation, or sterilization), research purposes (assisted reproductive tech niques, blood collection for genetic health analysis, radio-collaring), conservation and management purposes (capture of problematic animals, translocation, and reintroduction), and marking of animals. Thus, the capture and handling of wild animals play a crucial role in wildlife conservation and management. Physical restraint has several limitations and is often unachievable, despite being easy to use and not posing much risk to the animals. Chemical restraint is the most reli able alternative to restraining wild animals and has been employed to relocate or treat animals, resulting in the rescue of many rare and critically endangered wild animals. Chemical restraining of wild animals is a huge responsibility and requires expertise to avoid losses caused by injuries, capture myopathy, and the incorrect use of tranquilizing and immobilizing drugs. Many wildlife veterinarians and for est managers lack such expertise and experience.

1.1. Introduction Wildlife management often requires interventions to safely handle and transport animals. Chemical restraint, also known as immobilization or tranquilization, is a technique widely used to facilitate these processes (Hernandez, 2014). It involves the administration of drugs to temporarily immobilize wild animals, allowing for various procedures such as veterinary medical examinations, tagging, relocation, or rehabilitation. This chapter provides an overview of the principles, methods, drugs, and considerations involved in the chemical restraint of wild animals. It has been often stated that the most important techniques required by the zoo veterinarian are those used in the capture and restraint of the patient. These techniques have developed into a highly technical science (Clarke et al., 2014). In the early days of zoos, the only practical method was to manually catch and hold the patient. Modern techniques, however, permit a veterinarian to shoot a CO2 powered gun, which discharges a projectile syringe at an animal resulting in complete immobilization of the animal (Jacques et al., 2009). This is accomplished without any physical contact between the patient and his captors.  

2.1. Classification of Fish Fish are incredibly diverse aquatic vertebrates. There are over 32,000 de scribed species of bony fish, over 1,100 species of cartilaginous fish, and over 100 hagfish and lampreys. Fish can be broadly classified into three groups: 2.1.1. Superclass Agnatha (Jawless fish): These are the most primitive fish, lacking jaws and paired fins. They have existed for over 500 million years. Examples include lampreys and hagfish. 2.1.2. Class Chondrichthyes (Cartilaginous fish): These fish have skeletons made of cartilage instead of bone. They have jaws and paired fins. Examples include sharks, skates, and rays. 2.1.3. Superclass Osteichthyes (Bony fish): This is the largest and most diverse group of fish. They have skeletons made of bone and have jaws and paired fins. Examples include tuna, salmon, goldfish, and many more.

3.1. Introduction Various procedures performed on reptiles often necessitate chemical restraint or general anesthesia. Even routine tasks like physical examination and transportation can pose challenges, particularly with large or uncooperative reptilian patients. For safety reasons, venomous species are typically evaluated under chemical restraint. The respiratory anatomy and physiology of reptiles differ significantly from those of more familiar mammals, influencing their response to commonly used anesthetic agents. Historically, anesthetics recommended for reptiles had notable metabolic effects, but inhalant anesthesia has become more popular in recent times. Nonetheless, in species capable of anaerobic metabolism, induction with these agents may not be feasible (Girling 2013).

4.1. Classification The class Aves, also known as birds, is a group of warm-blooded vertebrates characterized by feathers, toothless beaked jaws, laying hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweight skeleton. Birds are found worldwide and come in a variety of sizes, from the tiny humming bird to the massive ostrich. The classification of Aves can be broken down into two major subgroups: Palaeognathae and Neognathae. 4.1.1. Palaeognathae: Also known as ratites, these are flightless birds with f lat sterna (breastbones) that lack keels, which are important for flight muscle attachment. Examples of palaeognathae include ostriches, emus, rheas, and kiwis.  

Rodents and lagomorphs are two distinct groups of mammals, often mistaken for each other due to some shared physical characteristics. However, they belong to different taxonomic orders and possess several key differences 5.1. Rodents They belong to the order Rodentia and the example species include rats, mice, squirrels, hamsters, guinea pigs, beavers, and porcupines. Order Rodentia is the largest and most diversified mammalian group, differing widely in size, behavior, feeding habits, anatomy, and physiology. Based on the anatomy and functional differences of masseter muscles, it is divided into 3 suborders viz., Caviomorpha, Myomorpha, and Sciuromorpha. Caviomorpha is also called hystrichomorpha and includes guinea pigs, chinchillas and degu. The suborder Myomorpha includes mice, rats, hamsters and gerbils. These animals have the strongest ability to gnaw among animals in all 3 suborders. Sciuridae is a family that includes small or medium size rodents. This family consists of tree squirrels, ground or medium size squirrels, and large size squirrels also known as marmots or prairie dogs (Cynomys ludovicianus). Smaller and less bushy tailed squirrels are known as chipmunks (Tamias striatus) and flying squirrels (Glaucomys volans).

Carnivora is an order of placental mammals that have specialized in primarily eating flesh, whose members are formally referred to as carnivorans. The order Carnivora is the fifth largest order of mammals, comprising at least 279 species. They come in a very large array of different body plans with a wide diversity of shapes and sizes. The common characteristics of carnivores are given below: • They are meat eaters. • There is the presence of canine teeth. • The intestinal tract is short and is adapted to rapid digestion as well as the assimilation of meat. • All species have anal glands. Some species, like the striped skunk (Mephitis mephitis), may eject the contents of the anal gland as a defensive maneuver. • Os penis is present in males. • There is a lack of a clavicle which helps in the freedom of movement of the forelimb. • Ulna is well developed. • Toes end in claws.

7.1. Introduction Chemical restraint of insectivores is a technique used by veterinarians and wildlife biologists to immobilize small mammals that primarily eat insects, such as shrews, moles, and hedgehogs. It is essential for performing examinations, administering medications, and conducting research on these animals. There are several factors to consider when chemically restraining insectivores: • Species: Different species of insectivores may have varying degrees of sensitivity to different drugs. • Age and health: Younger and healthier animals generally tolerate chemical restraint better than older or sick animals. • Temperature: Insectivores are sensitive to temperature regulation, so it’s crucial to maintain a stable body temperature during restraint.

8.1. Classification The ruminants belong to the Order Artiodactyla. The families in order of Artiodactyla include Camelidae, Tragulidae, Cervidae, Giraffidae, Antliocapridae, and Bovidae. The family Camelidae includesGuanaco (Lama guanicoe), Llama (Lama glama), Alpaca or South American camelid mammal (Lama pacos), Dromedary camel (Camelus dromedarius), and Bactrian or two-humped camels (Camelus bactrianus). The family Tragulidae includes Chevrotains originate from Africa (Hyumo schusaquaticus) and Chevrotains that originate from Asia (Tragulus species). The family CervidaeincludesWhite tailed deer(Odococlius virginianus), Follow deer (Dama dama), Roe-deer (Capreolus capreolus), Axis deer (Axis axis), Reindeer (Rangiter tarandus), Musk deer (Moschus species) and Chinese water deer (Hydropotes species).

9.1. Classification: Order Perissodactyla The order Perissodactyla, also known as odd-toed ungulates, is a group of herbivorous mammals characterized by having one or three toes on each foot. They are distinguished from even-toed ungulates (Artiodactyla) by this anatomical feature. Even-toed ungulates, such as pigs, cows, and deer, have an even number of toes (two or four) on each foot. Some of the well-known members of this order include horses, zebras, asses, tapirs, and rhinoceroses. The name “Perissodactyla” comes from the Greek words “perissos,” meaning “odd,” and “daktylos,” meaning “finger or toe,” referring to their unique foot structure. Unlike even-toed ungulates (Artiodactyla), which bear weight on their third and fourth toes, perissodactyls primarily bear weight on their third toe.

10.1. Classification of Primates The classification of primates is a complex topic that has been revised over time as our understanding of these fascinating creatures has evolved. Here’s a breakdown of the current classification system: 10.1.1. Order: Primates Primates are an order of mammals that includes lemurs, lorises, tarsiers, monkeys, apes, and humans. They are characterized by a number of shared features, including: • Opposable thumbs: This allows primates to grasp objects and manipulate their environment. • Forward-facing eyes: This provides primates with depth perception, which is important for arboreal locomotion and foraging. • Enlarged brains: Primates have relatively large brains for their body size, which is associated with their intelligence and complex social behaviors. • Reduced sense of smell:Compared to other mammals, primates have a weaker sense of smell. This is thought to be due to their reliance on vision for foraging and social interaction.

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