Housing husbandry and welfare provision for animals used in toxicology studies: Results of a UK questionnaire on current practice (1994)
Data Page
Published by Universities Federation for Animal Welfare
© UFAW 1995
Mice
Introduction
Fifteen replies were received from establishments that used mice for toxicity studies. The questionnaire did not differentiate between the types of study conducted which range from eg those requiring five or six weeks housing (so-called 28 day studies) up to life time carcinogenicity studies. There was the opportunity to differentiate between dietary, gavage or other routes of administration. A number of establishments used more than one strain or husbandry system.
Animals
The most commonly used strain was the CD1, with nine of the fifteen establishments using it. Other strains only occurred once or twice and therefore could not be used to provide reliable strain-specific details.
Thirteen establishments bought animals from commercial suppliers and four had facilities for breeding on site. Ear punch was the most common method for identification (seven respondents) with tail tattoo (four respondents) and electronic chip (four respondents) being the other methods used.
Caging
Cage dimensions and number per cage
There were 11 different cage sizes with floor areas ranging from 360-1260cm2 and height from 12-14cm. Between one and five animals were kept per cage. Males were more likely to be kept singly, though three establishments said they kept all animals singly. In the case of group-housed animals cage floor area ranged from 87cm2 to 315cm2 per animal. About half the respondents who housed animals in groups used floor areas of between 100 and 200cm2 per animal. Singly-housed animals were kept in cages with floor areas of 495cm2 to 1260cm2.
Cage construction
The caging itself was mostly opaque 'plastic' with solid bottoms and mesh tops. Clear 'plastic' and stainless steel were the other two materials. Four respondents used mesh or grid floors.
Visibility
Generally there was no visual contact between neighbouring cages. Racks or cages had to be moved for good observation by the operator.
Bedding
For the solid floors, sawdust, wood granules or shavings were almost universally used, the only exception was where a compacted paper bedding was used. Where there were mesh or grid floors, absorbent paper was placed on trays underneath. Sawdust alone does not allow the mice to build covered nests, and only seven of the fifteen establishments provided some material that could be used for nesting purposes.
Cleaning
Bedding changes were generally twice per week (all bedding being removed each time) with the cage shell being washed mainly weekly or twice monthly. Several had less frequent washing, with the greatest interval being monthly.
Environment
Light
Lighting where measured (11/15 respondents) was varied but 50lux inside the cage seemed to be the standard. A few establishments measured light regularly but others only sporadically. All establishments used a 12:12hr light/dark cycle. Only one had the capability for a dawn/dusk facility.
Noise
Noise levels were not generally measured, but in the four places where they were, background levels varied between 30 and 60dB (not specified whether this was the dBA scale).
Diet
There was some variation in diet type probably reflecting the time that the animals were kept and the type of study that was being conducted. Powder diet was used by 10/15, expanded diet by 6/15 and pellets by 5/15 sites. Expanded diet was far more likely to be used in establishments that also used a powder diet probably for the non-dietary studies and/or stock animals (five out of six sites). Why expanded should have been preferred to pelleted diets in these cases is not clear. Apart from one case, pelleted diets were used solely by establishments that did not carry out diet studies. There might, however, have been some confusion between the terms 'pelleted' and 'expanded'.
Handling
Aggressiveness, abnormalities and responses to handling were separated into those from gavage and dietary studies because of the expected differences in handling frequency.
Handling frequency
Diet studies: frequency was generally once or twice weekly, whereas in gavage and other studies: handling was normally daily.
Handling for enrichment
There was no real pattern of handling response. Animals were taken out of their cages for technical procedures only. There was no evidence that animals were handled for enrichment. The CD1 appears to be slightly more docile than the other strains but it is likely that the skill of the handler generally determines the ease of handling and the potential aggression towards the handler.
Aggression
It is well known that male mice are highly aggressive to each other so precautions are taken routinely eg putting into groups at weaning with no subsequent transfer of animals or housing individually. Aggression to other animals was mainly confined to male/male interactions. There was no difference between dietary and gavage studies.
Observed behaviour
Biting of cages was noted in the two establishments using BALBc mice at 13% and 98% when they were used for non-dietary or gavage type studies. The type of study was immunology in the former but was not mentioned in the latter. Handling frequency was between 2 and 5 times per week in both establishments.
Non-specified stereotypical behaviour was also noted by establishments using two other strains at 2% and 5%, otherwise it was not mentioned or given as less than 1%.
Other behaviours reported were barbering (common in C57, on one site only), circling (13% of animals in CD1) and obesity in two establishments at about 5% for group-housed C57 and B6C3 (5 per cage), and 10% for singly-housed B6C3. At one site excessive grooming was noted at about 20% in home bred B6C3 on gavage studies. These mice were handled more frequently (21 - 25 times per week) than others in the review.
Physical problems
Sore hocks (3% of animals) were noted in one dietary studies establishment that had grid flooring. Malocclusion of teeth was reported as rare. Obesity was noted at two establishments.
Procedures to improve welfare
Very little had been done on environmental enrichment:
Piped music had been used in two establishments both of which felt that it had helped to improve the background, presumably by reducing startle responses.
Soft paper in various forms had been tried in three establishments at which it was held to be successful.
Cardboard inserts (possibly the centres of paper rolls) had been tried but were not considered successful in another establishment.
Rats
Introduction
Fifteen replies were received from establishments that used rats for toxicity studies. The questionnaire did not distinguish between the types of study conducted which ranged from those requiring five or six weeks housing (so called 28 day studies) up to life time carcinogenicity studies. Some laboratories employed more than one system and/or used more than one strain of rat.
Animals
Nine establishments used the Sprague-Dawley CD rat, bought commercially. Four used an unspecified Sprague-Dawley strain, two of which were home bred. Five used Wistar rats, three of which were home bred. Two establishments used F344, both from a commercial supplier.
The most common was the commercially purchased CD rat.
Fourteen out of the 15 establishments used ear punching as a method of identification. Four used microchips and one establishment used ear tags.
Caging
Cage dimensions and number per cage
Most cages for multiple housing were 20 to 22cm high, 50 to 55cm long and 32 to 39cm wide. It would seem that several establishments quoted external rather than internal cage measurements. The RC2 cage was specifically named by 4 establishments, and was probably used by more, based on cage measurements. One establishment housed females in smaller cages than males.
Single cages were 20cm high, 25 to 27 cm wide and 27 to 48cm long (the short cage seems to have been used only for younger, smaller rats).
All respondents put four or five rats in a cage. Three establishments also used single-housing.
Cage construction
Four establishments used a steel shell, seven used clear plastic and five used opaque plastic.
Eleven establishments used grid bottoms and five used solid bottoms.
Eleven establishments used mesh tops and four used solid tops.
Visibility
Eight establishments considered rats were visible to those in other cages. Four believed this was not so and there was doubt in the case of three establishments (those using opaque plastic cages).
Thirteen establishments believed that their animals could see staff. Three had reservations.
Nine considered that staff had to move cages or racks to allow good visibility of animals. Four (all using clear plastic caging) did not believe it was necessary. One establishment used clear cages but still believed it was necessary to move racks or cages to see animals properly.
Bedding
The five establishments using solid bottomed cages used compressed paper chips, wood shavings, sawdust or dust-free shavings.
Cleaning
The bedding in solid bottomed cages was changed two to three times per week. None of the respondents deliberately left any old bedding in the cage.
Trays were cleaned from once daily to once weekly, but generally two to three times per week.
Some of the respondents changed the cage shell twice per week, probably related to changing bedding in solid bottomed cages. Most establishments changed cage shells once per two weeks though two changed shells monthly, including those using solid bottomed cages.
Environment
Lighting
All establishments used a 12:12hr light/dark cycle. One had a dawn/dusk facility.
Most establishments measured light intensity occasionally. Two implied it was done regularly and one had never done it.
Room level figures varied widely from 200 to over 500lux in 4 establishments. One establishment had 150lux background but increased to 300lux when technicians were working.
Cage level figures again varied widely, from about 20 to 100lux inside cages.
Noise
Ten establishments had not measured background noise, two had done so but data were not readily available and three gave figures all in the range 30 to 60 dB (not specified whether this was the dBA scale).
Diet
A low energy, low protein maintenance diet was used by 8 of the 11 establishments which provided details.
Pellet, powder and expanded diets were all used. Four establishments indicated they used powder alone. Five used pellets and 6 expanded, often with powder used as appropriate. It is possible there was some confusion between the terms 'pellet' and 'expanded'.
All establishments fed ad lib. One was investigating restricted feeding.
Handling
The responses for handling, aggressiveness and abnormalities were separated into those from gavage and dietary studies because of the expected differences in handling frequency. Twelve establishments reported on gavage studies, nine establishments reported on dietary studies.
Handling frequency
Gavage studies
Handling was daily for all except one establishment which estimated about 20 times per week. This meant animals were out of their cages from five to about 60 minutes per week depending on the establishment.
Dietary studies
Animals were handled two to three times per week. One establishment estimated daily handling and two, weekly handling. The time out of the cage was estimated as around five minutes per week.
Handling for enrichment
Gavage studies
One establishment encouraged petting but there was no other handling for enrichment. Most establishments believed the rats welcomed handling. Five indicated it was accepted and only one thought that handling was avoided by the rats.
Dietary studies
No establishment reported handling for enrichment. Two establishments considered animals welcomed handling, four believed they accepted but three thought that their rats avoided being handled.
Aggression
Gavage studies
Only one establishment considered there was more than rare aggressiveness to people or other animals. There was nothing unusual in the environmental factors to explain this.
Dietary studies
Aggressiveness to people or other rats was considered rare or non-existent in most establishments but was reported as common in one establishment (the same establishment as reported it in gavage studies) and as an occasional occurrence, worsening with age in another establishment.
Observed behaviour
Gavage studies
Very few abnormal behaviours were described by any establishment. Three or four reported occasional incidences of barbering, self inflicted trauma and biting the wire of cages. Biting the wire was reported at a higher incidence in two further establishments, one establishment suggested it happened with most animals occasionally, the other suggesting a 30% incidence.
Dietary studies
A similar pattern of behavioural abnormalities to that in gavage studies ie very low reported incidence.
Physical problems
Gavage studies
Sore hocks were reported in about 50% of establishments, usually associated with older/larger animals. The incidence was up to 20% of the susceptible population. Obesity was reported in four establishments, including one establishment using Wistar rats (a strain not normally prone to obesity, but it may be significant that this establishment also used a higher protein diet). Malocclusion was reported in two establishments.
Dietary studies
Sore hocks were again reported and so was obesity. Malocclusion was mentioned as significant in only one establishment.
Other studies
The main alternative type of study was reproductive, multi-generation or other littering type of study. For these studies, solid bottomed cages were used. Most establishments provided paper for nesting. One of which reported transferring nest material (but not bedding) between cages when cleaning them.
Apart from a possibly increased incidence of females biting the wire of cages, there were no apparent differences versus other studies.
Intravenous studies were also mentioned but conditions and responses were similar to those for gavage studies.
Procedures to improve welfare
Several procedures were described to improve the welfare of rats. However, virtually no objective data were available to assess the success or otherwise of any of them. No procedures attempted were described as failures.
Environmental controls
Reduced light intensity (to compensate for clear plastic cages).
Dual intensity lighting, which could be reduced when technicians were in the room, to reduce the incidence of retinal dystrophy.
Piped music, presumably to reduce startle responses.
Cage design
An area of solid floor. Rats were said to prefer the solid areas and the darker areas.
The provision of more space per animal.
Within cage environment
The provision of bedding. Said to be successful - but this establishment uses grid bottomed cages so there might have been a recording error.
The provision of boxes in cages and paper tissues for bedding. Solid bottomed cages were used in this establishment.
In reproductive studies the provision of paper for nest making was frequently mentioned.
The provision of dust-free bedding.
Social provision
Group-housing.
Caging animals in view of other animals.
Handling techniques
Petting during gavage dosing.
Petting of animals encouraged.
Single animals handled daily, which was said to reduce aggressiveness.
Guinea Pigs
Introduction
Guinea-pigs are used mainly for sensitisation studies. Eleven questionnaire returns were received. The questionnaire asked for separate responses for sensitisation studies as opposed to other types of study for the sections on handling, aggression and abnormalities.
Animals
Ten of the eleven sites purchased their animals, only one site bred their own guinea-pigs. Ten sites used the Dunkin Hartley strain, one did not name their strain (which was home bred). Depending on the precise protocol details they will be about 6-9 weeks in the laboratory.
Cages
Cage dimensions and number per cage
Cage sizes varied from 1,260cm2 to 6,100cm2. One site used pens with a floor area of 14,628cm2. Assuming the weight range provided in the Introduction: the cages at three of the sites could be classified as generous (at least double the minimum space recommended by the Home Office Code of Practice); five complied with the code; and three were apparently providing less than the Code of Practice minimum. The powers of the Home Office Inspectorate are discretionary, and it is possible that some other aspect of the housing system compensated for any space limitation.
Only two sites single-housed their animals, two pair-housed them and the others group-housed in groups of three, five, six and one group of ten.
Cage construction
Eight out of eleven respondents used all metal cages, two used polycarbonate cages, one used clear and one used opaque cages. Only one site used floor pens. Two sites had solid floors (one cage, one floor pen made out of polypropylene and concrete respectively).
Visibility
The majority (eight of the respondents) reported that their animals were able to see other animals and staff. Only four respondents were able to see their animals without disturbance of the cage and equipment.
Bedding
The majority of establishments provided no bedding or nesting material, but three supplied hay which can be used as bedding.
Cleaning
Tray cleaning varied from daily to once per week. Complete cage cleaning varied from weekly up to once every six weeks. Two respondents cleaned daily, one on alternate days. Two respondents cleaned once per week and one respondent did not comment.
Environment
Light
Only three establishments measured light and noise on a regular basis and then only infrequently. Room light levels varied from 100 to 600lux, while within the cages it ranged from 10 to 300lux. The exterior lighting for the room with pens ranged from 215 to 233lux while within the pens it was 220-242lux. There was also a facility to increase these levels for handling purposes. All sites used a 12:12h light/dark cycle, and no site had dawn/dusk arrangements.
Noise
None of the sites reported any noise measures.
Diet
All sites used commercially produced pelleted diet. Only three supplied hay as food/bedding. Only one gave vegetables. Only six sites stated they used Vitamin C, but this may be confusing as in most cases the diet listed included Vitamin C.
Handling
Only one site encouraged staff to handle for enrichment. One site did not handle at all, one handled 25-30 times per week. The time out of the cage per week varied from 0-90 minutes. Nine sites stated that contact was avoided.
Aggression
None of the respondents reported aggression to humans or other animals.
Observed behaviour
Very little abnormal behaviour was reported. Only two respondents reported any incidence of abnormality ie wire biting (10% and 70% incidence rates).
One site reported a 5% incidence of self inflicted trauma following procedures (presumably resulting from scratching). Hay and forage are generally accepted to prevent barbering, so considering how few sites fed hay there was a surprisingly low incidence (1% in only one report).
Physical problems
Sore hocks and malocclusion were only reported in three groups and even then they were considered unusual.
Procedures to improve welfare
There were only three reports of real environmental enrichment, although several respondents said that they were considering enrichment. None gave positive evidence of the benefits of environmental enrichment.
Environmental controls
One site felt that background music made the animals calmer.
Cage design
One group was evaluating a solid floor.
Within cage environment
The same group that was evaluating solid flooring was also evaluating wooden blocks.
One site provided boxes and hay.
Only one group considered that providing hay was of benefit.
Rabbits
Introduction
Thirteen responses were received. The establishments surveyed rarely conducted studies where the rabbits were held for more than 8 weeks.
Animals
Eleven of thirteen respondents used the New Zealand White of which one of these referred to the 'small' strain. The two remaining used Dutch.
Caging
Cage/pen dimensions and number per cage
Three of thirteen had tried floor pens but only one was using this method for toxicity studies. The respondents did not state the gender of the animals used in these housing trials.
All caged animals were singly housed apart from one company who was attempting to run teratology females in groups of three.
Standard metal cages were approximately 60 x 74 x 45cm while the plastic ones were 80 x 70 x 45cm. One company gave the dimensions for a floor pen for six rabbits that measured 190 x 235 x 243cm.
Material and form of cage
Plastic and solid cages were used with equal frequency. Four of thirteen used grid floors while the remainder used punched floors.
Visibility
Several respondents commented that the animals could not hide from staff. For animals in cages, there was no visibility from animal to animal except to those directly opposite. Visibility in pens was not an issue within the groups, but groups could not see each other as the pens had solid sides.
Bedding
Seven of thirteen respondents offered hay for nesting or diet supplement. Animals in pens had either paper chips or sawdust together with hay and straw.
Cleaning
Tray cleaning was generally performed two or three times per week. Complete cage cleaning was generally carried out monthly although three respondents cleaned the cages weekly or fortnightly. Floor pens were dismantled and cleaned every three months.
Environment
Lighting
Not all the respondents measured lighting levels. Where reported, room levels ranged from 100 to 450lux while within the cages the levels ranged from 30 to 114lux. The pen-housed rabbits had a normal inside pen reading of 218-256lux, with a facility to increase this level for handling, etc. Few sites measured light levels routinely and there was no dawn/dusk facility. Duration of light phase was 12h except for teratology (14h).
Noise
Noise was only measured by two respondents (one stated 50-60dBA), while the other did not specify levels.
Diet
The two major diet manufacturers were represented. Two of thirteen respondents restricted the diet (one stated 120g per day). Supplements included hay in seven cases and cabbage/carrot in one case.
Handling frequency
The majority of respondents handled the animals once daily. During procedure this frequency increased (up to 30 times per week in one case).
Handling for enrichment
Only one respondent handled for enrichment.
Aggression
There was a mixed response to this question. Generally the animals avoided contact with staff but were not aggressive on handling. In one of the establishments there were occasional incidents of aggression to humans with the Dutch rabbit.
One of the respondents who supplied data on floor pens commented that animals previously held in cages showed aggression towards each other if subsequently pen-housed. In the two cases where pair-housing had been tried it was considered to be unacceptable because of aggression between the animals.
Observed behaviour
There was a very mixed response concerning cage biting ranging from 0 to 100%, but no correlations could be drawn from the data. It was apparently absent in the small NZW strain.
Only two respondents had seen self inflicted trauma, mutilation/barbering/circling, in both cases commenting that the behaviour was rarely seen.
Physical problems
There was evidence that inappetance was a problem in both Dutch and NZW. Addition of hay clearly reduced the incidence or eradicated it completely. Several respondents gave positive comments on the beneficial use of hay. There was a lower incidence of hairball than inappetance and again the problem could be alleviated with the use of hay.
There was a low incidence of enteritis, and there were no obvious correlations with husbandry or strain.
Three sites holding rabbits for long periods reported a low incidence of sore hocks (particularly heavy animals). In one case the floor type was a grid floor, in the other two cases dimpled floor. One establishment reported that the problem had been alleviated after changing to a plastic flooring.
Four respondents indicated an incidence of malocclusion of 1-2%.
Six respondents indicated an incidence of broken limbs of 1% or less. There was no correlation with cage type.
Procedures to improve welfare
Seven of thirteen respondents tried enrichment of some form and all those who tried hay continue to do so for toxicity studies. Of the other forms of enrichment, one site continues to use vet bed and shelving whilst the respondent using group-housing continues to do so. The procedures attempted, together with reports of success/failure, are listed below. The most common form of enrichment was hay (seven respondents), vet bed (two respondents) and plastic pipes/cardboard boxes (two respondents). All the others listed had only been attempted at one site.
Handling/rooming for inappetance success.
Group-housing in floor pen success.
Group-housing of pregnant females failure.
Plastic pipes/cardboard boxes success.
Pair-housing failure.
Shelf success.
Vetbed success.
Wooden chews under evaluation.
Linked cages (three) under evaluation.
Hay success.
Dogs
Introduction
Responses were received from nine establishments using laboratory beagles.
Seven respondents gave details of more than one study type (dietary, gavage etc), although in one case the answers given were the same for both study types. One establishment gave information for two different study types without explaining which type was the second study.
Animals
All except one user gave the country of origin of their animals. Two respondents stated the actual strain of beagle used, four omitted to confirm that the dogs used were in fact beagles.
Three users stated that they obtained their dogs from their own in-house breeding colonies and two from other named user/breeder establishments. The remainder (four establishments) used dogs from one or more commercial breeders, mainly in the UK but occasionally abroad, including USA.
Pen
Pen dimensions and number per pen
One questionnaire was returned without a response to this section. Six respondents indicated that their dog pens were 4.5m2 or more in floor area. One establishment appeared to have pens of two sizes, 3.9m2 and 6.8m2 respectively. One establishment which housed all animals singly had pens with a floor area of 3.86m2 at the time the questionnaire was completed; at the time of publication the unit in question is no longer being used.
Seven respondents stated that they housed dogs two or more to a pen; of these, two held some if not all dogs in groups of four. Six out of the seven replies indicated that animals were routinely separated for feeding and the seventh establishment fed animals separately if fighting or bullying occurred. One user housed animals singly all the time and one did not answer this part of the questionnaire.
Pen construction
Exact details of pen construction were not readily discernible although seven respondents stated that pen floors were solid (two nil replies). Construction of dividing walls and surfaces varied with five respondents indicating that pen divisions were solid up to a given height (two gave dimensions of 50cm and 60cm), with meshwork, bars or glass above. Two establishments held animals in pens with solid walls although one mentioned that it was considering a redesigned pen without solid walls. One user had pens with glass/vertical bar dividers and gave the answer solid or mesh.
Partitions, visibility and ability to hide
In three establishments pen design incorporated partitions which partially obscured visibility of other dogs and/or staff. Pens in the other six establishments utilised dividers which were not considered to impair visibility. Only one establishment stated that animals could hide from other animals or staff. Two users considered that their pens allowed animals to hide to a degree and one respondent was investigating introducing pen furniture which would allow animals some privacy.
Bed provision
Two establishments had no form of raised bed, one provided a raised bed board and three used pens with a raised rear floor portion, one of which was heated. Three respondents merely stated raised bed which is ambiguous.
Bedding
Replies from six establishments indicated that no bedding was provided for sleeping; two users stated that sawdust or woodchip was used. One respondent simply answered in the affirmative although since raised bed boards were used, the term bedding may have been taken to mean just that rather than absorbent litter.
Sawdust was provided by most establishments for absorbency. Two replies indicated that no absorbent litter was provided and a further one gave none/sawdust as a reply. One questionnaire was returned without an answer to this question. One user commented that the sawdust litter often became quite wet.
Cleaning
Four users reported employing a combination of wet and dry cleaning methods, three used only wet cleaning methods and two dry cleaned the pens.
With one exception, in all establishments pens were cleaned on a daily basis. (One site dry cleaned the pens every two days.) Where a combination of wet and dry methods was employed, wet cleaning was carried out either weekly or every two to three weeks.
The respondents were asked whether dogs remained in their pens during cleaning. One reply suggested that the animals had no choice but to remain in their pen, and dry cleaned daily. Two other establishments gave a yes/no answer without qualifying what was meant by this, and one stated that the dogs could choose whether to stay in the pen or run up and down the central aisle because the pen gates were left open. In other cases animals were removed from the pen when it was being cleaned.
Exercise arrangements
Most establishments had some provision for exercise although specific details were given in only a few cases. Some allowed animals to run in central corridors during pen cleaning whereas others set aside specific times for social interaction. Responses to the later section on handling overlapped with exercise and it was difficult to draw definite conclusions about precisely how much time was allowed for socialisation, exercise and handling. Two establishments had provision for outside exercise areas; one establishment appeared not to offer any exercise period, the implication being that pens of 4.5m2 and 10m2 were adequate exercising space for two and four dogs respectively.
Environment
Light at night
The questionnaire did not ask for the photoperiod. Two sites replied that some lighting was provided at night; one of them stating that night lights were used.
Noise limiting measures
Four establishments reported having no sound deadening measures in place and one did not reply to this section. One simply answered in the affirmative without giving details, one mentioned the use of sound absorbing plastic paint which was ineffective, and one described acoustic tiles on the upper walls.
Diet
All establishments fed pelleted diet and from the responses given by seven out of the nine users it could be deduced that expanded pellets were used. (Two sites merely stated pellets.) Powdered diet (for dietary studies) was used also in two of the nine establishments. All except one restricted feeding, most by amount fed, although two centres limit the time during which food was available to the animal.
Handling
The layout of the questionnaire appeared to cause some confusion in this section. In particular, the question Time per week out of pen, intended to elicit a measure of time, was answered by four out of the nine respondents as though it asked times per week out of pen. Typically, dogs were handled at least once per day on all studies except dietary, when the frequency of handling was usually only once weekly. Responses to the question about handling for enrichment varied from no, through if time permits or during procedures to once weekly. Two users reported that masks were worn in the unit (all the time), one stated that masks were not worn and the remainder indicated that masks would be worn only when required by the hazard of the compound being administered.
Aggression
With regard to evidence of 'problems', aggression towards people was reported by two establishments as rare or very rare, one quantified it (nominally) at 1%, and in five out of the nine establishments it was not observed. Three sites stated that aggression to other animals did not occur, and six reported it as rare, very rare, occasional or 1%. One establishment had no problems because dogs were housed singly.
Observed behaviour
Biting the wire of the pen was seen in animals housed at three of the sites and the incidence was given as rare, less than 5% and 30%. Five establishments saw no evidence of this behaviour and one described the incidence of all abnormal behaviour as too low to quantify. Self inflicted trauma was not recorded in seven out of the nine establishments, and as rare and seldom in the other two. Circling was observed in four establishments the incidence being recorded as 'sometimes' (two establishments), 1% and 'less than 1%', although no indication was given as to the circumstances under which the animals were monitored (closed circuit TV, direct observation through viewing panels, technician in room etc).
The only comment elicited about other abnormal behaviour was that one user noted occasional vocalisation among singly-housed animals. A question relating to aversion to handling elicited responses of approximately 1%, rare, occasionally and sometimes. Some aversion to strangers was observed in animals from six of the nine establishments. Two cited an incidence of 10% and one 25%, although this latter figure was obtained from monitoring only eight dogs! There was no obvious relationship with any other provision of housing and care mentioned in these establishments.
Physical problems
The questionnaire asked only about the presence of obesity in dogs; two establishments reported incidences of 'less than 1%' and 'sometimes'.
Procedures to improve welfare
One establishment did not reply to this section of the questionnaire. All other respondents described a variety of procedures to improve welfare which had been tried and all but two gave some indication of the success or failure. Comments made under this heading centred around provision of a varied environment, provision of toys, human socialisation, inter-dog socialisation, and acclimatisation to procedures.
Cage design
Inside and outside pens.
Dog boards.
Within cage environment
Low wooden boxes open on one side tried with young dogs - proved popular as nest boxes, something to climb on and to chew.
Frames and ramps for stock animals - reported to be used by less than 25% of animals.
Toys introduced by staff - dogs enjoyed being played with but quickly tired of a toy which can become an object of aggression if animals are left unsupervised.
Chews and strong rubber toys - tried but discontinued on veterinary advice because dogs were consuming them.
Toys tried during exercise period - dogs paid more attention to each other and to handlers.
Dog/human social provision
Walking on leads.
Grooming, regular handling.
Handling, petting during procedural work - animals reacted with enthusiasm to handlers and handling.
Dog/dog social provision
Housing to maximise visual contact with other dogs.
Housing in pairs whenever possible.
Exercise sessions, eg in small groups in central aisle - one respondent considered that it reduced frustration.
New pen design (groups of four animals per large pen with doors to subdivide, eg for feeding, sleep shelves) - dogs very relaxed and quick to settle in.
Socialisation programme in breeding unit. This has resulted in decreased nervous/aggressive behaviour.
Acclimatisation to study procedures
Acclimatisation to restraint, eg confinement in metabolism cages for short periods, restraint without the dosing/sampling procedure, grooming while restrained - all reported as successful.
Non-Human Primates
Introduction
A total of ten responses were received from six different establishments using primates. The questionnaire was divided into gavage/capsule studies and 'others'. Five respondents gave details of a study type other than gavage but in only one case was the type specified (a breeding colony). In four cases the answers given were the same for both study types.
Animals
Five sites used Old World primates. One respondent used wild-caught baboons from Kenya (Papio anubis). Two used rhesus macaques, five used cynomolgus (the crab eating macaque Macaca fascicularis). In all cases the primates were stated as captive-bred, obtained from The Philippines, Mauritius and China.
Five respondents used captive-bred marmosets (Callithrix jacchus); these would all, almost certainly, have been bred in the UK. One of these five respondents was a breeding establishment which did not carry out research.
Four out of the five sites using Old World primates used tattoos for marking, but one working with cynomolgus used implants. Marking techniques for marmosets were varied, two sites using tattoos, two using collar and tag. One site used microchips alone, while another was moving from collars to microchips. Only one site, working with marmosets, acknowledged that the technique (tattooing) might cause momentary distress.
Caging
Cage dimensions and number per cage
Old World primates
Four of the five sites using Old World primates housed them singly in cages of 0.64, 0.69, 0.8 and 0.98m2 floor area. Heights of the cages were 100, 95, 230 and 220cm respectively. One site had the facility of pairing cages which increased height from 110cm to 230cm. Only one site currently group-housed their animals by age (6-8 in a cage) with a floor area of 2.58m2 and height 201cm, and with additional outdoor runs. Pairing was being tried at one site, under consideration at another, while yet another was converting their cages to allow four animals to share four cages for most of the time.
Marmosets
Marmosets were normally housed in pairs at three of the sites, one site single-housed, and in breeding units they were kept in family groups of 6-8 animals. Cage sizes varied from 0.28m2 floor area (height 79cm) to 0.33m2 (height 82cm) for single and pair-housed marmosets. A breeding facility housed their animals in cages with 0.72m2 floor area and 170cm height.
Cage construction
Old World primates
The walls (presumably not the fronts) were usually solid being made of aluminium, stainless steel or in one case 'Trespa' (a hard artificial board). One respondent mentioned a small viewing panel, and another used cages with one solid side and three mesh sides.
The bottoms consisted of bars or mesh, in one case with a solid wooden portion. The outdoor site used a cement base.
In two cases the tops were mesh, in the other three they were solid. The outdoor facility provided mesh.
Marmosets
Four of the five sites provided solid walls, presumably with mesh fronts. Only one site used stainless steel mesh walls. Only two sites provided mesh tops to the cages, and three sites used cages with solid tops and walls. Three sites used mesh flooring while two had solid floors.
Partitions, visibility and ability to hide
None of the respondents felt that their cages prevented viewing of other animals, although two sites considered that their solid walls provided some restriction. None felt that the cages restricted viewing by staff.
Provision of retreats within the cages for the animals was more varied. The site with cynomolgus in indoor/outdoor pens was the only site using Old World primates, whose cages allowed the animals to hide from each other, although two other sites thought that there was provision to 'partially' or 'almost' hide.
Three of the five sites using marmosets thought that their marmosets could hide from each other, in two cases through the use of nest boxes. One of the sites that responded negatively to this question was a breeding site, and the other housed their animals in pairs.
Environment
The primate questionnaire did not include questions on lighting or noise levels.
Diet
Commercial primate diets were used at all sites. Old World primates generally had a much less varied standard diet than marmosets. Only one site provided an additional (unspecified) forage feed. All marmoset sites provided extras to the standard diet. These included: meat, rice, brown bread, condensed milk, fortified milk drink, maize flakes, sultanas, peanuts, banana and/or other fresh fruit.
The differences between the standard diets provided to Old World primates and marmosets were probably not important because supplementary foods, which may vary from day to day, were commonly given to both Old World primates and marmosets. For Old World primates these included fruit (bananas, apples, oranges, grapes) as well as brown bread, Prima Treats, blackcurrant juice and Vitamin B12 supplements. One site provided only oranges, but the other sites provided a variety of supplements. Marmosets also received a range of supplements that included fruit as well as marshmallows, sunflower seeds, forage mix, Farley's rusk, marmoset jelly, tinned fruit and malt loaf.
None of the sites that group-housed their primates separated them for feeding.
Foraging
Three sites with Old World primates, and three sites with marmosets were either using or experimenting with providing the normal food ration via foraging. Only one site housing Old World monkeys provided food ad lib. while four out of the five marmoset sites provided food ad lib.
Handling and behaviour
The questions for handling, aggression and abnormalities were separated for gavage/capsule studies and for other types of study which the respondents were asked to specify. All sites provided responses for gavage/capsule studies but only four sites included data under 'other' types of study. Two did not specify study type and the other two referred to breeding/stock animals. As the 'other' responses did not differ significantly from gavage studies, the data are amalgamated except where otherwise specified.
Frequency of handling
As expected, handling frequency under gavage was at least daily and in one case greater than twice daily. Masks were worn at all sites with Old World monkeys, but at one site only for specified tasks.
Masks were used regularly at three of the marmoset sites and sometimes at one marmoset site. One site did not use masks. Handling time was of the order of 15-35 minutes. Handling of stock animals was less frequent.
Response to catching
It was generally felt that the initial response of most animals was to avoid catching, but some sites thought that this response improved with time and that there was considerable variation between animals. In one case a site keeping cynomolgus and rhesus macaques felt that their animals welcomed catching.
Response to strangers
Old World monkeys were thought to be either wary or curious. One site reported threatening behaviour in some but not all animals. Marmosets were thought to be curious by virtually all the respondents, often emitting vocalisations.
Aggression
Old World primates
Two sites considered their Old World primates not to be aggressive to people while the three other sites thought that this behaviour only occurred occasionally. Three sites (who housed their animals singly) felt that there was no aggression to other animals, while two (one of whom single-housed) considered that there was occasional aggression.
Marmosets
Only two out of the three marmoset sites considered that their animals were aggressive to people. One site, who single-housed, reported no aggression to other animals. The other sites reported occasional aggression.
Observed behaviour
None of the respondents reported seeing any behaviours that might be indicative of problems other than those specified on the questionnaire, that is: biting the wire/shell of cage; self inflicted trauma; circling and weaving.
Old World primates
Behavioural abnormalities appeared to be more common in Old World primates than marmosets. This may have been due to the fact that they tend to be single-housed, as the site which group-housed their animals reported that the incidence of all specified abnormalities was too low to quantify. Biting the wire/shell of cage was occasionally seen at two of the Old World sites. At one establishment (two sites) self inflicted trauma, circling, and weaving were seen in about 2% of rhesus prior to transfer to larger cages. One other site reported an incidence of 1% for these behaviours.
Marmosets
There were no reports of biting wire/shell or self inflicted trauma. Two sites reported incidences of occasional (1%) and 0.3% respectively for circling, and the first site also had an occasional (1%) incidence of weaving. It was noteworthy that this was the only site to single-house their marmosets.
Enteritis
Old World primates
Three sites using Old World primates (cynomolgus) responded to a question on the incidence of enteritis, reporting figures of 0%, 2-3% and 5%.
Marmosets
All five sites using marmosets responded to this question. Two sites had no cases, one less than 1% and two sites a 1% incidence.
Injuries due to cage design
Old World primates
Four sites responded. Two sites had had no injuries, one site had an incidence of 1% but also reported occasional injuries due to fighting (0.5%). One site reported a figure of 6% over a one year period, however, they also mentioned that a change of design had reduced this to 1-2%.
Marmosets
All five sites responded, three sites had no cases, while the remaining two sites had a 2% incidence rate.
Procedures to improve welfare for Old World primates
Recreational provision was very varied. Four of the five sites had tried to improve welfare or provide recreational facilities. Some sites provided an assessment as to whether they considered them successes or failures. The site that group-housed cynomolgus provided the most options viz. tube, swing, wooden platforms, forage, hay, wood shavings and an outside view.
Environment
Music success.
Within cage environment
Wooden slatted sitting shelves success.
Rubber rings success.
Tubes success.
Swings success.
Toys only of initial value.
Ropes failure.
Waterbath still under trial.
Hay, wood shavings for recreation, success unspecified.
Social provision
Contact with human and non-human primates success.
View outside for recreation, success unspecified.
Pair-housing for a part of the day success unspecified.
Food
Provision of forage mix success.
Treat after dosing success.
Provision of Boneos failure.
Handling
No site handled Old World primates for enrichment purposes.
Procedures to improve welfare for New World primates
Generally more attempts to improve welfare were made for marmosets than for Old World primates. All five sites provided a range of options including social contact, in cage furniture and two sites provided extra-cage options
Environment
Music success unspecified.
Cage design
Prototype communal tunnel area connecting cages.
Planned assessment of gang cage housing eight animals.
Access to exercise cages once weekly seemed to be a success.
Within cage environment
Perch success.
Nest box (sometimes specified as wooden) success/very successful.
Heated nest box success.
Tunnel success.
Rubber rings failure.
Ladders success unspecified.
Swingssuccess unspecified.
Wood shavings success unspecified.
Vet Bed thought to be liked by infants.
Mobile furniture where studies permit.
Contact bedding little benefit.
Social provision
Housing in pairs one site reported that it was not always successful.
Social-housing (unspecified numbers) success.
Visibility to others success.
Re-socialisation of individuals where studies permit success.
House males and females in separate rooms success unspecified.
Food
Foraging two sites reported that their marmosets showed little interest.
Hanging fruit success.
Food treats success.
Variation of diet success.
Handling
No site handled marmosets under gavage studies for enrichment purposes, two sites gave the reasons that it could cause stress or abortions. Only one site occasionally handled marmosets under 'other' studies for enrichment purposes.
