Stray and unwanted cats (Felius silverus domesticus) are commonly admitted to animal shelters, where more than half are euthanased. As well as serious ethical issues associated with euthanasing healthy cats, research indicates that symptoms of perpetrator-induced traumatic stress syndrome are evident in 50% of people in occupations with duties directly associated with euthanasia of dogs and cats. The high numbers of animals euthanased have also been linked to high staff turnover in animal shelters.
Management of excess domestic cats in Australian society is a financial burden to the community, with local government spending an estimated A$82 million annually on management strategies. It is estimated that more than A$180 million is spent annually by animal welfare agencies to manage the problem of excess pets.[1, 4]
There is an urgent need to better understand the cat population that is entering shelters.[5-9] Limited statistical information, published annually by the Royal Society for the Prevention of Cruelty to Animals (RSPCA) in Australia, shows that, in the past 7 years, there has been little decrease in the number of cats entering shelters, and no reduction in the numbers being euthanased. However, this information does not include detailed descriptions of the characteristics of cats entering shelters and information from other countries is also limited. The number and variety of organisations, the large size of the respective cat populations, the geographic size of each country, logistics of obtaining data from paper-based records and some unwillingness by shelters to provide data, all contribute to the lack of statistics on unwanted pet populations in the USA and Australia.[10-15]
The lack of detailed information about the characteristics of cats entering and exiting shelters means that the reasons for the current numbers of cats being euthanased are difficult to understand, which in turn creates difficulties in developing, implementing and evaluating strategies to manage the situation.[9, 16, 17]
There are an estimated 386,000 owned cats in Queensland, with an average of 90 cats per 1000 people. This is approximately 17% of Australia's owned cat population. Cat admissions to RSPCA shelters in Queensland (RSPCA-QLD) account for approximately 25% of the national RSPCA intake annually. The aims of this collaborative study were to describe the characteristics of the cat population entering RSPCA-QLD shelters and to identify risk factors for euthanasia after entry.
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- Materials and methods
The overall euthanasia rate of 65% in the present study was similar to that reported from a study of 134,405 cat admissions to 176 shelters in Michigan (71%). However, in both studies there was considerable variation between shelters, which in our study was only partially accounted for by differences in cat factors. Human socioeconomic factors influence cat populations and may explain some differences between shelters. A recent study in Boston found that 77% of the variation in cat euthanasia between neighbourhoods was explained by numbers of human premature deaths at the neighbourhood level, suggesting that the same constellation of socioeconomic factors that negatively affect human health may also strongly influence cat mortality in shelters. Shelter capacity and shelter policies and procedures may also explain differences. A detailed study of these factors is needed to help identify strategies that would effectively reduce cat admissions and risk of euthanasia.
The euthanasia rate for kittens in our study (61%) was lower than reported from an earlier study of one shelter in Victoria (72%). An important consideration when comparing studies, however, is that RSPCA-QLD defines kittens as ≤3 months of age, whereas other reports have defined kittens as ≤6 months of age.[7, 22, 25] If the euthanasia risk for kittens between 3 and 6 months of age differs relative to adult cats and kittens less than 3 months, comparisons of results with other studies are potentially invalid, highlighting the need for standardised age category definitions.
Although the percentage of kittens euthanased (61%) in our study was lower than for adults (71%), a greater number of kittens were euthanased because more were admitted. Thus, strategies to reduce the total number of cats euthanased should include a major focus on reducing kitten numbers entering shelters. This may also benefit adult cats, as fewer kitten admissions may increase adoption opportunities for adult cats.[17, 27]
The percentage of cats desexed prior to admission in this study (13%) was higher than previously reported in Australia (4%), possibly because of our method of identifying desexed status prior to admission; however, RSPCA staff advised that our method of categorisation was likely to be accurate. Additionally, our results are similar to those of previous studies from the USA, reporting prevalences from 9% to 13%. Although the majority of owned cats in Australia are desexed (approx. 90%),[18, 29-31] only 34% of owner-surrendered adult cats were categorised as desexed, which suggests there are important differences between cat owners who surrender their pets to shelters and other cat owners.
Given that 54% of all admissions were cats aged less than 3 months of age, and that almost half of these were surrendered, it is clear that, despite the high prevalence of desexing in domestic cats in Australia, excess breeding is still a key contributor to shelter admissions. There is evidence that many owned cats produce kittens prior to being desexed, with reports that at least 13–20% of owned female cats had produced a litter prior to desexing.[33, 34] Although female cats can have their first oestrus as early as 3.5 months, approximately 45% of cats in one USA study were at least 1 year old when they were desexed and it was calculated that the average sterilised cat had 2.46 kittens before being sterilised. In fact, the number of kittens born from cats that were ultimately desexed was calculated to be only slightly less, and not statistically different, than the number of kittens born from cats that were never desexed.
Reducing the number of kittens born to owned cats as a result of delaying sterilisation is therefore an important strategy for those seeking to reduce shelter admission numbers. A potential factor contributing to unwanted kittens being born to owned cats is the reluctance of veterinarians to incorporate early-age desexing (EAD) into initial preventative health programs for owned kittens. Given that mortality associated with EAD is not higher than traditional age desexing (>6 months) and that subsequent health and behaviour are better in cats desexed at less than 5 months of age, veterinarians should embrace EAD as a means of reducing euthanasia rates and the subsequent adverse mental health effects on the personnel involved.
A previous report concluded that the domestic cat population in Australia is becoming smaller and suggested that high levels of desexing among owned cats may limit the availability of kittens for purchase or adoption. However, a recent Australian study determined that only 2% of cat owners experienced difficulty sourcing a kitten for purchase or adoption. Those who did experience difficulty usually required a specific breed or were attempting to obtain a kitten out of breeding season. The results of our study confirm that kittens are not in short supply within Queensland.
Strays were the single largest (45%) admission group, although this percentage may not reflect the true proportion of strays. Some people present owned cats as strays because they do not want to admit to surrendering their own animal and/or are unwilling to pay the fee (Reid, pers. comm.). RSPCA-QLD charges a small fee per private cat admission, but not for stray cats. Also, admissions not presented by the general public (22% of adults, 12% of kittens) were unable to be classified as stray or owned and may comprise a higher proportion of strays than general public admissions. Because stray cat admissions will not be directly influenced by strategies that focus on owned cats (e.g. mandatory registration and microchipping, desexing, etc.), additional strategies focussed on stray cats are required to reduce overall admission numbers.
‘Semi-owned’ cats may constitute an important subset of ‘strays’. In Australia and the USA, there are reports of ‘semi-owned’ populations of cats that are fed by people who do not perceive the cat as their own. In a Victorian study, 22% of survey respondents said that they provided care, including food, to a cat that was not their own. This indicates that there is a substantial population of cats in the community that are tolerant of human interaction, but not under the direct influence of legislative requirements for pet ownership.
There may also be a large population of ‘pre-owned strays’ in Queensland. Although the crude risk of euthanasia was higher in strays than in cats surrendered by owners, after adjusting for other variables in the multivariable model the stray cats in our study were actually at lower risk of euthanasia. This reflects the finding that many of the cats admitted as ‘strays’ were suitable for rehoming and 16% were categorised as having been desexed prior to admission, which suggests that at least 16% of the ‘stray’ cats older than 3 months had been ‘pre-owned’ at some point prior to admission. The actual percentage of pre-ownership may be much higher.
It is commonly speculated that a considerable portion of cats euthanased in Australian shelters are feral. One study of cats entering three urban shelters in Melbourne reported 47% of euthanased cats as feral or wild. By contrast, in our study only 19% of euthanased cats were recorded as feral. As described in the Methods section, cats are categorised as feral by the RSPCA based on a subjective visual assessment of behaviour, often at the time of arrival at the shelter when the cat may be extremely distressed. This is likely to be inaccurate, as indicated by the fact that 6% of owner-surrendered cats in this study were recorded as feral. An alternative definition based on the cat's apparent level of socialisation towards humans may be more accurate. However, if data in the current study are accurate, the majority of cats euthanased in RSPCA-QLD shelters are tolerant of human proximity and interaction, and therefore potentially rehomable.
The percentage of cats reclaimed was very low (3%) in the current study. Of cats that were reclaimed, only 13% were categorised as microchipped prior to admission. The true prevalence may be even lower because of inaccurate data recording. Of all 36,736 cats admitted during our study, 29% were categorised as being microchipped prior to admission: 33% of kittens and 25% of adult cats. In contrast, Marston and Bennett reported that 1.5% of 15,206 cats admitted to a Melbourne shelter were recorded as having a microchip detected on admission. The high prevalence in our study, especially in kittens, suggests that our method of interpreting the microchip data resulted in frequent misclassification errors. Further inquiry indicated that microchip number was recorded in the same field within the database, regardless of whether the cat was microchipped prior to or after admission, and that for cats microchipped after admission, staff often entered the microchip number but neglected to record the date of implantation. Under our categorisation method, such cats would have been erroneously classified as being microchipped prior to admission. The estimated prevalence of microchipped prior to admission in reclaimed cats is therefore reported, but likely to be an overestimate. This finding indicates that microchipping was not an important factor in owner reclamation of cats from RSPCA-QLD. Accurate recording of microchip status at admission is important because it allows the effect of mandatory microchipping (promoted as a means of reducing euthanasia of lost owned cats) to be assessed. We did not ascertain if reclaimed cats had other forms of identification (e.g. collars and identification tags) on admission. However, microchips do not provide a visual indication of a cat's ownership status and identifications tags may play a vital role in reuniting lost cats with owners prior to, or following, shelter admission.
Some of the limitations of this study were related to the methods used by shelters to record and manage data collection. Computer-based record keeping systems are becoming more common, enabling higher quality research. However, high levels of data integrity and consistency in terminology are necessary for valid research. Consistency is challenging when data are entered by numerous people in multiple shelters, and when there are no overarching requirements for the data that shelters are required to collect. Some variables that may not seem important from an operational standpoint, such as microchip status prior to admission, are essential data for developing effective strategies to decrease euthanasia numbers.