Genetics and Genomics of the Rabbit, The

Luca Fontanesi, Luca Fontanesi

• Publisher: CAB International
• Year: 2021
• ISBN:
  9781789249484
• Topic: Biological Sciences
• Subtopic: Biology
• Index: Biological Sciences

Rabbits have many uses - as well as being cherished pets, they are bred for their meat and fur, and as laboratory animals. Understanding their genetics and genomics is key to their production and, equally, to their care, welfare and health. Beginning with an introduction to the rabbit, including key information on their evolution, domestication and breed types, this book then concentrates on the genetics and genomics of this valuable animal. This book covers: - Cytogenetics, genetic maps and QTL mapping;- Immunogenetics;- Genetics of coat colour, meat, fibre and fur production, reproduction, disease resistance and more.Concluding with practical applications such as creating transgenic and genome edited rabbits, biotechnical applications and the rabbit as a biomedical model, this book brings this important topic fully up-to-date. It provides an indispensable resource for animal and veterinary researchers and students, as well as rabbit breeders and laboratory scientists.

1 The Evolution, Domestication and World Distribution of the European Rabbit (Oryctolagus cuniculus)

Luca Fontanesi¹*, Valerio Joe Utzeri¹ and Anisa Ribani¹

¹Department of Agricultural and Food Sciences, Division of Animal Sciences, University of Bologna, Italy

1.1 The Order Lagomorpha

The European rabbit (Oryctolagus cuniculus, Linnaeus 1758) is a mammal belonging to the order Lagomorpha.

Lagomorphs are such a distinct group of mammalian herbivores that the very word ‘lagomorph’ is a circular reference meaning ‘hare-shaped’ (Chapman and Flux, 1990; Fontanesi et al., 2016). A unique anatomical feature that characterizes lagomorphs is the presence of small peg-like teeth immediately behind the upper-front incisors. For this feature, lagomorphs are also known as Duplicidentata. Therefore, instead of four incisor teeth characteristic of rodents (also known as Simplicidentata), lagomorphs have six. The additional pair is reduced in size. Another anatomical characteristic of the animals of this order is the presence of an elongated rostrum of the skull, reinforced by a lattice-work of bone, which is a fenestration to reduce the weight (Chapman and Flux, 1990; Rose, 2006). The herbivorous diet and the terrestrial mode of life are the primitive conditions of this order (López-Martínez, 1985). All lagomorphs are also characterized by a specific feeding behaviour known as caecotrophy, that is the re-ingestion of soft cecal-derived faeces needed to assure essential vitamin uptake, the digestion of the vegetarian diet and water reintroduction (Hörnicke, 1981).

The order Lagomorpha was recognized as a distinct order within the class Mammalia in 1912, separated from the order Rodentia within which lagomorphs were originally placed (Gidely, 1912; Landry, 1999). Lagomorphs are, however, considered to be closely related to the rodents from which they diverged about 62–100 million years ago (Mya), and together they constitute the clade Glires (Chuan-Kuei et al., 1987; Benton and Donoghue, 2007). Lagomorphs, rodents and primates are placed in the major mammalian clade of the Euarchontoglires (O’Leary et al., 2013).

Modern lagomorphs might be evolved from the ancestral lineage from which derived the †Mimotonidae and †Eurymilydae sister taxa, following the Cretaceous-Paleogene (K-Pg) boundary around 65 Mya (Averianov, 1994; Meng et al., 2003; Asher et al., 2005; López-Martínez, 2008).

The systematics of the order are not completely clear yet and currently under revision by the International Union for Conservation of Nature and Natural Resources (IUCN), Species Survival Commission (SSC), Global Mammal Assessment, and Lagomorph Specialist Group (LSG). The order is divided into two families (Fig. 1.1; Hoffmann and Smith, 2005; Chapman and Flux, 2008; Fontanesi et al., 2016): (i) Ochotonidae (the pikas), with 26 teeth, and (ii) Leporidae (the jackrabbits and hares, and the rabbits), with 28 teeth. According to the most accepted taxonomy, these two families account for a total of 92 living species (Chapman and Flux, 1990; Fontanesi et al., 2016; Melo-Ferreira and Alves, 2018).

Fig. 1.1. Schematic representation of systematics of the order Lagomorpha (number in parenthesis indicates the number of species within the genera). (Modified from Fontanesi et al., 2016)

Fossil and molecular estimates are not completely in agreement in the identification of the evolutionary split between these two extant families. Fossil data seem consistent in indicating that the divergence period occurred before 42 Mya (Ruedas et al., 2018) even if molecular estimates based on mitochondrial and nuclear genome sequences have placed this family split in a more recent period (about 30 Mya; Matthee et al., 2004). Merging fossil data and molecular estimates, the differentiation time has been placed around 50 Mya (Meredith et al., 2011).

The list of all recognized extant lagomorph species is reported in Table 1.1. The family Ochotonidae comprises 29 species of small (70–300 g) egg-shaped mammals with distinct rounded ears and no visible tail. All species have been assigned to the genus Ochotona. They have hind legs not much longer than the fore legs. Most of these species are vocal. There are two major groups of pikas (Smith, 1988; Smith et al., 1990; Lissovsky, 2014): (i) those that live in rocks or talus have low reproductive rates and are generally long-lived; they are territorial either as individuals or pairs and have extremely low rates of social interaction; and (ii) those that live in meadow or steppe habitat and burrow; they have high reproductive rates and are generally short-lived; these species form extended families and are highly social. These groups have been divided into five subgenera (Alienauroa, Conothoa, Lagotona, Ochotona, and Pika), commonly recognized mainly considering their distribution (Hoffmann and Smith, 2005; Lissovsky, 2014). A recent phylogenomic analysis recognized four subgenera of extant pikas (Alienauroa, Conothoa, Ochotona and Pika), with the mountain group Conothoa being the sister group of all other pikas (Wang et al., 2020).

Table 1.1. List of lagomorph species. (From Chapman and Flux, 1990; Fontanesi et al., 2016; Melo-Ferreira and Alves, 2018)

Family/genus	Species	Common name
Ochotonidae
Ochotona	O. alpina	Alpine Pika
	O. argentata	Helan Shan Pika
	O. cansus	Gansu Pika
	O. collaris	Collared Pika
	O. coreana	Korean Pika
	O. curzoniae	Plateau Pika
	O. dauurica	Daurian Pika
	O. erythrotis	Chinese Red Pika
	O. forresti	Forrest’s Pika
	O. gloveri	Glover’s Pika
	O. hoffmanni	Hoffmann’s Pika
	O. hyperborea	Northern Pika
	O. iliensis	Ili Pika
	O. koslowi	Koslov’s Pika
	O. ladacensis	Ladak Pika
	O. macrotis	Large-eared Pika
	O. matchurica	Mantchurian Pika
	O. nubrica	Nubra Pika
	O. opaca	Kazakh Pika
	O. pallasii	Pallas’s Pika
	O. princeps	American Pika
	O. pusilla	Steppe Pika
	O. roylei	Royle’s Pika
	O. rufescens	Afghan Pika
	O. rutila	Turkestan Red Pika
	O. syrinx	Qinling Pika
	O. thibetana	Moupin Pika
	O. thomasi	Thomas’s Pika
	O. tutuchanensis	Turuchan Pika
Leporidae
(the rabbits)	Brachylagus idahoensis	Pygmy Rabbit
	Bunolagus monticularis	Riverine Rabbit
	Caprolagus hispidus	Hispid Hare
	Nesolagus netscheri	Sumatran Striped Rabbit
	Nesolagus timminsi	Annamite Striped Rabbit
	Oryctolagus cuniculus	European rabbit
	Pentalagus furnessi	Amami Rabbit
	Poelagus majorita	Bunyoro Rabbit
	Pronolagus crassicaudatus	Natal Red Rock Hare
	Pronolagus randensis	Jameson’s Red Rock Hare
	Pronolagus rupestris	Smith’s Red Rock Hare
	Pronolagus saundersiae	Hewitt’s Red Rock Hare
	Romerolagus diazi	Volcano Rabbit
Sylvilagus	S. aquaticus	Swamp Rabbit
	S. audubonii	Desert Cottontail
	S. bachmani	Brush Rabbit
	S. brasiliensis (sensu stricto)	Tapetí, Andean Cottontail, Rio de Janeiro Dwarf Cottontail
	S. cognatus	Manzano Mountain Cottontail
	S. cunicularius	Mexican Cottontail
	S. dicei	Dice’s Cottontail
	S. floridanus	Eastern Cottontail
	S. gabbi	Gabb’s Cottontail
	S. graysoni	Tres María Cottontail
...