Following the closure of the original West End production, a nationwide tour embarked in 2003 with Chrissie Hammond starring as Grizabella,[146][147] until Dianne Pilkington took over the role in 2006.[148] Hammond reprised the role on tour again from 2007 to 2008.[149][150] A UK tour of Cats launched in February 2013 at the Edinburgh Playhouse with Joanna Ampil as Grizabella,[151][152] running through 2014 before transferring to the West End.[153] In between its limited West End runs, the musical returned to the Blackpool Opera House Theatre in 2015, this time starring Jane McDonald as Grizabella.[154][155] After the second West End revival, the production toured the UK in 2016 with Anita Louise Combe as Grizabella and Marcquelle Ward as Rum Tum Tugger.[156][157]
Domestic kittens in developed societies are usually vaccinated against common illnesses from two to three months of age. The usual combination vaccination protects against feline viral rhinotracheitis (FVR), feline calicivirus (C), and feline panleukopenia (P). This FVRCP inoculation is usually given at eight, twelve, and sixteen weeks, and an inoculation against rabies may be given at sixteen weeks. Kittens are usually spayed or neutered at seven months of age, but kittens may be neutered as young as seven weeks (if large enough), especially in animal shelters.[20] Such early neutering does not appear to have any long-term health risks to cats, and may even be beneficial in male cats.[21] Kittens are commonly wormed against roundworms from about four weeks.[22]

The musical first played in Mexico from April 1991 to November 1992;[120] the Spanish-language production performed over 400 shows and starred María del Sol as Grizabella,[130] Manuel Landeta as Munkustrap,[131] Susana Zabaleta as Jellylorum, Maru Dueñas as Sillabub and Ariel López Padilla as Macavity.[132] A revival premiered at the Teatro San Rafael in May 2013, with an opening night cast that included Filippa Giordano as Grizabella, Landeta, and Maru Dueñas.[133] After a total of 350 performances, the show closed at the Teatro San Rafael in June 2014,[134] and then toured over 36 cities in Mexico until December 2014.[135][136] Other performers who later joined the production included Lisset,[137] Rocío Banquells,[138] Lila Deneken and Myriam Montemayor Cruz, all of whom played Grizabella.[139] Another Mexican revival was launched at the Coyoacán Centennial Theater in October 2018, with Yuri as Grizabella and Landeta as Old Deuteronomy.[131][140] The revival marked its 200th performance in May 2019.[141]
The cat skull is unusual among mammals in having very large eye sockets and a powerful specialized jaw.[66]:35 Within the jaw, cats have teeth adapted for killing prey and tearing meat. When it overpowers its prey, a cat delivers a lethal neck bite with its two long canine teeth, inserting them between two of the prey's vertebrae and severing its spinal cord, causing irreversible paralysis and death.[67] Compared to other felines, domestic cats have narrowly spaced canine teeth relative to the size of their jaw, which is an adaptation to their preferred prey of small rodents, which have small vertebrae.[67] The premolar and first molar together compose the carnassial pair on each side of the mouth, which efficiently shears meat into small pieces, like a pair of scissors. These are vital in feeding, since cats' small molars cannot chew food effectively, and cats are largely incapable of mastication.[66]:37 Although cats tend to have better teeth than most humans, with decay generally less likely because of a thicker protective layer of enamel, a less damaging saliva, less retention of food particles between teeth, and a diet mostly devoid of sugar, they are nonetheless subject to occasional tooth loss and infection.[68]
Another unusual feature is that the cat cannot produce taurine,[note 1] with a deficiency in this nutrient causing macular degeneration, wherein the cat's retina slowly breaks down, causing irreversible blindness.[103] This is due to the hepatic activity of cystinesulfinic acid decarboxylase being low in cats. This limits the ability of cats to biosynthesize the taurine they need from its precursor, the amino acid cysteine, which ultimately results in inadequate taurine production needed for normal function. Deficiencies in taurine result in compensated function of feline cardiovascular and reproductive systems. These abnormalities can also be accompanied by developmental issues in the central nervous system along with degeneration of the retina.[118]

Cats are ready to go to new homes at about 12 weeks of age, when they are ready to leave their mother.[184] They can be surgically sterilized (spayed or castrated) as early as 7 weeks to limit unwanted reproduction.[185] This surgery also prevents undesirable sex-related behavior, such as aggression, territory marking (spraying urine) in males and yowling (calling) in females. Traditionally, this surgery was performed at around six to nine months of age, but it is increasingly being performed before puberty, at about three to six months.[186] In the US, about 80% of household cats are neutered.[187]

The domestic cat is a significant predator of birds. UK assessments indicate they may be accountable for an estimated 64.8 million bird deaths each year.[155] A 2012 study suggests feral cats may kill several billion birds each year in the United States.[222] Certain species appear more susceptible than others; for example, 30% of house sparrow mortality is linked to the domestic cat.[223] In the recovery of ringed robins (Erithacus rubecula) and dunnocks (Prunella modularis), 31% of deaths were a result of cat predation.[224] In parts of North America, the presence of larger carnivores such as coyotes which prey on cats and other small predators reduces the effect of predation by cats and other small predators such as opossums and raccoons on bird numbers and variety.[225] The proposal that cat populations will increase when the numbers of these top predators decline is called the mesopredator release hypothesis.
The scientific name Felis catus for the domestic cat was proposed by Carl Linnaeus in the 10th edition of Systema Naturae published in 1758.[1][2] Felis catus domesticus was a scientific name proposed by Johann Christian Polycarp Erxleben in 1777.[3] Felis daemon proposed by Konstantin Alekseevich Satunin in 1904 was a black cat specimen from the Transcaucasus, later identified as a domestic cat.[38][39]