CHAPTER 1
CATS AND DOGS – THEIR LIVES WITH HUMANS
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Doubtless it was because of their usefulness to us that certain animals were domesticated. They provided food, clothing, materials for habitations, transport, protection, and rodent control. And animals sharing our habitation also gained in particular ways, by having regular food and shelter, for instance. Companion animals like the dog and the cat have shared our habitat for thousands of years.

Humans and dogs have a very long shared history. Recent studies suggest that dogs lived with Stone Age humans. Some have suggested that dogs and to some extent cats have co-evolved with humans – where some change in a genetic trait in one species brings about change in the behaviour and often the genes of the other (1,2) . Humans are capable of making strong emotional bonds with dogs, cats and many other animals, and vice versa.

Domestic cats (Felis catus) belong to the family Felidae, which includes lions, tigers, cheetahs, lynx, panthers and other efficient carnivores. Most members of this family hunt their prey and often have camouflaged fur. The Felidae all have sharp retractile claws and the ability to run, climb and leap in pursuit of their prey.

There are signs from archaeological work in Cyprus that the cat may first have established a tenuous bond with humans more than 8 000 years ago. Bones of humans, cats and mice have been found together – cats being used to control rats and mice in grain stores. Better evidence of domestication can be found in 4 000 BC Egypt. Farming settlements in the Nile delta have been excavated and found to contain cat remains. It is likely that at this time cats were both working animals and also human companions. The cat domesticated by the Egyptians was Felis silvestris libyca, a subspecies of the wild cat. It was a large cat with tabby markings and of a reddish orange colour and may have crossbred with the swamp cat, descendants of which are still found in the Middle East today.

From about 1 000 BC the Egyptians held the cat in high regard and large numbers were bred in temples and subsequently worshipped. Cats were considered manifestations of the cat-headed goddess Bastet, who was associated with beauty, motherhood and fertility. Early traders would have introduced the Egyptian cat to other places within the countries of the Mediterranean and gradually throughout Europe and Asia. Cats are now to be found anywhere in the world where there are people.

Whilst cats are essentially lone animals enjoying solitude and their own company, dogs are sociable and group animals. Dogs have been found in fossil records of human habitations going back to Palaeolithic times when it is possible that their domestication began. The domestic dog Canis familiaris is essentially a descendant of the wolf (Canis lupus) with many of the aggressive traits that are found in wild populations of the wolf bred out. The domestic dog arose in East Asia around 15 000 years ago. This suggestion is made on the basis of studies where the genes of wolves and dogs from around the world are compared (3).

Domestic dogs from at least five different domestic lineages probably accompanied humans across the land bridge from Siberia to Alaska and down into the Americas around 12 000-14 000 years ago, according to work by Jennifer Leonard and her colleagues (4). At this period in the world's history such dogs were possibly used as sentinels, for transport and for herding buffaloes and mastodon in hunts.
However long has been the association between dogs, cats and humans there is a deep understanding, especially between dogs and us. Dogs pick up human hints about hidden food better than do chimpanzees or human-reared wolves, Brian Hare and his colleagues have shown (5). Puppies excel, regardless of their age, at following a human’s gaze or pointing to food, even if the animals have had little experience of humans. Even though dogs are distant from us in their evolutionary history they seem to have so closely evolved with us that they ‘think like we do’ on certain issues.
Clearly dogs and cats have shared a great deal of our history and have helped shape our communities and social structure. They are obviously individuals with their own personality and history but we are far more powerful than they and so, in a society which claims to be humane and based upon justice we owe them a special duty of care. Such a duty calls upon us to safeguard their interests and needs – to recognise that they, like us, enjoy rights, have a sense of self and can suffer in many, often subtle, ways.

Companion animals and compassion
Dogs and cats have been used in basic research and medicine for several centuries. They have been subjected to surgical procedures, paralysed and made to suffer especially in the early years of the nineteenth century when there were no anaesthetics or analgesics. In those days, scientists using these sentient creatures would maintain that unlike humans cats and dogs did not suffer, they were merely machines and science and understanding were far too important to be limited by compassion or the rights of non-human animals.

Furthermore, many within the Christian Church still maintain that non-humans do not possess that gold standard for our concern: the soul. Whilst others argue that if this were true, the one life afforded to non-human animals is all the more precious to them. Within the Christian tradition one can find positive approaches to the life of animals. For example that animals have value to God independently of their value or use to us; that animals exist in a covenant relationship with God and humankind and therefore there is a clear moral bond between us; and for Christians Jesus Christ is a moral exemplar in his sacrifice of love for all creation. Others, who embrace non-Judeo Christian approaches to the world such as Buddhists and Jains, have compassion for all who share the planet with us.

In order to undertake the very minimum of duty and care toward those animals that have shared our homes and lives for so long it is essential to have a sound grasp of the needs and basic husbandry of dogs and cats used in research.

The Cat : Basic biology and social organization
Cats are solitary intelligent animals with the capacity to be highly sociable. Feral cats are nocturnal and mark their territories with urine and anal gland secretions. Feral males defend quite extensive areas covering the smaller territories of females, and are polygamous (6).
Cats communicate by vocalization, facial expression, postural changes, and scent. They demonstrate affection and aggression towards other cats and humans, but if unused to people will be nervous if approached. Staff responsible for the care of cats within the laboratory can do much to reduce stress and anxiety by adopting a gentle and quiet approach. Cats can sense the attitude of humans very rapidly and will respond accordingly. Cats lack dominance hierarchies and do not appear to have means whereby reconciliation can be sought after a conflict, therefore in the laboratory context, forming social relationships may be highly stressful. Clear signs that cats are stressed are not as straightforward to interpret as are those in dogs.

A cat’s perception of the world is very different from ours. Hunting by sight at night cats rely upon the ability to see and discriminate between objects at lower light intensities than humans. Therefore lighting levels in laboratory housing is important -- low levels of lighting should be sufficient for cats to retain their vision and to take account of the startle reflex. Inappropriate lighting can inflict high levels of stress (7). Cats can also follow rapid movements and augment their visual sense with sound. Cats are very sensitive to ultrasound which are used by their prey species to communicate. In addition cats use the sense of smell to find suitable prey. Smell is also used to communicate via the vomeronasal organ and involves marking familiar areas.

Young cats are agile, inquisitive and playful and need, at the very minimum, an environment that engages their range of behaviours. Adult females can be kept together and will become used to one another whereas males will fight over available females. Best practice dictates that male cats who are not littermates should be separated at 4-6 months.

Cats can adapt to a wide range of population densities and wild domestic cats – feral animals – show a variety of social structures depending upon food availability in addition to absolute numbers of animals (8). Colonies of feral cats can range from one to 2000 animals per square km (9).
Usually female cats become sexually mature at around nine months of age. Males are sexually mature by around eight months – although some may be fertile by 6-7 months, good husbandry of animals in laboratory breeding colonies takes account of the age of the cats being housed.
An average litter size is four, and 104 males are born to every 100 females . Pregnant cats need a dark undisturbed place in which to give birth and again this has to be taken account of in breeding colonies in order to avoid stress and mortality of kittens. There is also the need to protect kittens and young cats from attack from males.

General husbandry considerations
Husbandry systems should use best health care practice, which stresses good welfare and meet the animals' behavioural needs. Systems should provide safe, comfortable, animal-directed conditions, an environment that meets those specific needs of cats. Physical activity and mental stimulation should be provided. Particular attention should be paid to housing and environmental enrichment to maximise the welfare of animals used in research. In particular no more that 12 animals should be held together, and where cats are normally group-housed, single housing may be a significant stress factor. There should be overwhelming evidence that there is a specific scientific and welfare need for animals to be held singly for more that 24 hours but, as the Case Studies in this Report indicate, animals are often held in isolation for extended periods of time without an adequate case being made.

Best practice also stresses the need for careful monitoring of cat colonies in order to identify and remove causes of stress and anxiety – animals should have adequate social space, especially when females are nursing kittens, to avoid conflicts with aggressive cats. In addition it is necessary for cats to have sufficient human contact in order to accustom them to later handling by humans. Research articles often lack detail of such considerations when describing the research protocol being followed.

In order to optimise cat environments and housing in research facilities emphasis should be given to providing raised, part-enclosed structures in order for the animals to have a view of their surroundings and, if pair- or group-housed, the opportunity to maintain a comfortable distance from other cats. Enough structures should be provided so as to reduce competition. Wood should be available for scent-marking and claw-sharpening.

As partly social animals it is clear that it is important for cats to have early exposure to other cats (for example litter mates) and with humans. Daily handling is advised during these early days (two to eight weeks of age) so as to develop the social behaviour of the adult cat. It has been shown that a short period of handling by humans, even on the first day after birth, is of importance to the formation of social behaviour, since young animals can respond to tactile and scent stimuli and this informs their view of the world (11).
Lack of sufficient detail in research publications describing experiments making use of cats and dogs lead to difficulties in making judgements as to whether minimum standards of husbandry and care are being adhered to.

The Dog : Basic biology and social organization
Dogs (Canis familiaris) are co-operative, inquisitive, docile (when well socialised) and of a suitable size to make them attractive for a variety of research purposes. The most widely used dog for research purposes is the beagle. Dogs are highly gregarious and intelligent mammals with a complex range of social behaviours (12). There is a very wide range of breeds which differ in size, needs and temperament. Wild canids, such as the various strains of wolves, are communal animals that hunt in packs. The pack as a whole runs down the chosen prey and co-operates in its killing. Packs comprise very marked male and female dominance hierarchies, and mating is monogamous, as in all wild canids.

In the Asiatic wolf (Canis lupus pallipes), the species which is widely considered to be the most closely related to the domestic dog, pack members are hostile to wolf strangers and so they form strongly bonded family groups. By contrast the present day domestic dog has a far more open pack structure and differs from many of their wild relatives in being able to readily form strong social relations with human beings (13)

As is the case with the cat, dogs appear to have a critical period between 3 and 12 weeks of age when pups should socialise with humans in order to develop those traits which lead to future social bonding with humans. During this sensitive period pups must have regular contact and handling with human carers, because by the age of 14 weeks, a dog deprived of such socialization will show clear fear-motivated behaviour. This includes timidity, hyperactivity and aggressive body signs. Such animals become highly distressed when subjected to any simple non-invasive handling procedure. Dogs exhibiting such behaviour also have physiological variables such as heart-- and breathing-rates outside the normal values (14).

In the domestic dog, kept in groups, social dominance plays a very important part and it is easy for those members of the group lower in the dominance hierarchy to be denied food, water and the attention of those charged with the care of the group. As is the case with cats, dogs are intelligent animals and will respond well to firm but gentle treatment – unlike cats however, the care-giver must establish themselves as the dominant member of the group. Without the establishment of this dominance the care-giver will face aggressive and dominant behaviour from the dominant member of the group. When dogs are being used in certain kinds of experimental procedures it may be useful to be aware of their position in the hierarchy as this will influence a range of physiological factors – such as resting heart rate and levels of various hormones related to stress such as the corticosteroids.

Like cats, dogs have a rich and varied repertoire of visual and vocal displays -- these are used to signal greeting, sexual behaviour, anxiety and nervousness, submission and aggression. Dogs use similar signals for humans and other dogs, and such displays are very good indicators of future behaviour. Young dogs who greet humans confidently will tend to greet unfamiliar visitors in similar ways, which are non-aggressive, when they are older.

The sense of smell is extremely important to the life of the dog, male dogs will use urine marking as a means of marking its territory. Pups are able, from a young age, to engage in often complex and involved social behaviour. Unlike female dogs males tend to have a noticeably aggressive attitude to other male dogs, even litter mates. Female dogs on the other hand are far more tolerant and sociable to their own and the male sex. There are very wide individual and breed differences in behaviour and other psychological parameters (15). Barking for example, although common in many European breeds, is almost unknown in Basenjis.

Dogs of all breeds require exercise. Single housing of dogs is a significant stressor and animals should not be expected to remain alone for periods in excess of four hours. Tactile contact should be provided for all dogs, especially those housed singly during any part of the day.
Beagles tend to be the dog of choice for many laboratories and their physiological characteristics are well described. Beagles tend to weigh between 10 to 12 kg and live from 10 to 15 years. Larger breeds live for shorter periods and have higher heart rates, as would be expected.

General husbandry considerations
Indoor pens should be supplied together with spacious exercise areas with features which stimulate the sense of exploration. Hubrecht has shown that there are clear benefits for dogs if they are kept in low-noise environments with platforms and areas for resting. He further indicated that restricted environments or poor levels of human interaction resulted in stereotyped behaviour. Such abnormal behaviour included repetitive jumping, circling around the pen, pacing along a fence and paired social pacing in which dogs would pace in parallel with another dog on the other side of a fence (16). As is the case with cats, females with young have special needs and these include an area to which they can retire away from possible interference.

Daily interactions should involve both human care-givers and other dogs. It has been suggested, on the basis of research, that human contact may be even more important than contact with other dogs (17). Dog treats and toys provide welfare benefits so long as they are carefully monitored. As chewing is an important feature of dog behaviour items should be provided which meet this need (18). Young puppies appear to greatly enjoy human socialization and they made considerable use of various toys. Clear benefits of such enrichment can be found in adult animals. The Case Studies reporting the use of dogs lack any detail as to the social conditions in which animals live or their care whilst recovering from surgery and anaesthesia.

Anaesthetics and analgesics
Pre-medication with an appropriate sedative is advised by current guidelines for good husbandry , especially when preparing cats or dogs for surgery (19, 20), Pre-sedation reduces struggling which may be encountered even in very placid animals during induction of the anaesthetic. Pre-sedation also means a less stressful induction which is advantageous since it leads to a smoother recovery with a far lower dose of induction agent -- this overall means a far less traumatic experience for the animal. Such a practice does not appear to be followed in certain of the Case Studies reported in this Report (Chapter 6).

Analgesia should be given before the experience of pain is likely (21, 22). Sound and humane experimental technique stresses that analgesia be given to dogs and cats who are sedated, as they may be unable to demonstrate in any observable way the exact level of pain they are experiencing. Several of the Case Studies detailed in Chapter 6 do not specify if analgesia is administered later than immediately post-operatively. This is especially important when animals have had extensive surgery and allowed to recover, in some cases for up to one year. Deep surgery in these situations is highly likely to result in significant levels of pain for considerable periods.

Intubation to facilitate breathing is a highly problematic procedure in cats, as these animals have a very sensitive laryngeal reflex. A 2 per cent lignocaine spray plus lignocaine lubricated intubation tube will reduce the initiation of the laryngeal reflex and so ease breathing in deeply anaesthetised cats. Again it is unclear in the Case Studies examined whether this practice was followed.
Dogs and cats are extremely vulnerable in the post-operative period and it is essential that care and adequate facilities are provided (23). It is difficult to find sufficient detail in the publications used in the Case Studies to know if this has been followed.

Surgical anaesthesia calls for highly trained and conscientious staff who are aware of the various needs of the animals used in experiments. Those involved must be aware of the effects on effective and reversible anaesthesia of the age, sex, strain and species being used. Certain anaesthetic agents will augment some of the negative effects of surgical procedures – for instance in raising the blood pressure within the brain – and this may cause unforeseen pain and distress in those animals who are allowed to recover.

Developing safe and effective anaesthetic and analgesic regimens which facilitate the well being and pain-free recovery of all animals used in experiments calls for very careful evaluation of the kinds of agents used and the management techniques used to ensure the most comfortable and stress free experience post-operatively. Such an assessment needs expert veterinary input and a knowledge of both experimental and husbandry aspects of each procedure (24).

(1)K Soproni et al [2001] Comprehension of human communicative signs in pet dogs (Canis familiaris), Journal of Comparative Psychology, 115, 122-126
(2)K Soproni et al [2002] Dogs’ (Canis familiaris) responsiveness to human pointing gestures, Journal of Comparative Psychology, 116, 27-34
(3) P Savolainen et al [2002] Genetic evidence for an East Asian origin of domestic dogs, Science, 298, 1610-1613
(4) JA Leonard et al [2002] Ancient DNA evidence for Old World origin of New World dogs, Science, 298, 1613-1616
(5)B Hare et al [2002] The domestication of social cognition in dogs, Science, 298, 1634-1636
(6) S Wolfensohn & M Lloyd [1995] Handbook of Laboratory Animal Management and Welfare, Oxford: Oxford University Press
(7)S Wolfensohn & M Lloyd [1995] op cit
(8)S McCune [1999] The Domestic Cat, in: The UFAW Handbook on the Care and Management of Laboratory Animals, Volume 1: Terrestrial Vertebrates, Seventh Edition. Oxford: Blackwell Science
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(10) S McCune [1999] op cit
(11) S McCune [1999] op cit
(12)J Serpell [1995] The domestic dog; evolution, behaviour and interactions with people, Cambridge: Cambridge University Press
(13)MW Fox (Editor) [1975] The wild canids, New York: Van Nostrand Reinhold
(14) SL Vanderlip et al [1985] A socializing program for laboratory raised canines, Laboratory Animals, 14, 27-36
(15) JP Scott & JL Fuller [1965] Genetics and the social behaviour of the dog, Chicago: University of Chicago Press
(16) RC Hubrecht et al [1992] Correlates of pen size and housing conditions on the behaviour of kennelled dogs, Applied Animal Behavioural Science, 34, 365-383
(17) TL Wolfle [1990] Policy, program and people, In; Canine Research Environment, J A Mench and L Krulisch (Editors), Bethesda, Scientists Center for Animal Welfare
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(19) S McCune [1999] op cit
(20) P Flecknell [1995] Anaesthesia of animals in neuroscience, IBRO News, 23, 5-8
(21) S McCune [1999] op cit
(22) P Flecknell [1995] op cit
(23) J MacArthur Clark [1999] op cit
(24) P Flecknell [1995] op cit