Catch, Neuter and Release Programmes--The Pros and Cons
World Small Animal Veterinary Association World Congress Proceedings, 2009
Ray Butcher, MA, VetMB, MRCVS


The document Humane Dog population Management Guidance produced by the International Companion Animal Management Coalition (ICAM) has been discussed in previous lectures. This presents a framework for developing a coordinated humane dog population control strategy, and involves all relevant stakeholders agreeing to a plan incorporating a variety of intervention options. Sadly, the reality is often different. Programmes are often managed by NGOs who, although well meaning, have limited resources, minimal contact with other stakeholders, and lack clearly defined goals that are based on accurate population surveys. Catch / Neuter / Release (CNR) initiatives are often seen as the total solution, and the aim seems to be to neuter everything that moves without critically analysing the consequences of the intervention.

Basic Components of CNR Programme

In its traditional format, a CNR programme involves a number of steps:

 Catching the free roaming dogs within the area.

 Transporting the dogs to a central facility where the neutering is performed. This could be a permanent building or a mobile clinic.

 Performing surgical neutering, usually also adding some means of permanent identification.

 Usually the dogs are vaccinated at this time (especially for rabies) and may receive prophylactic worming or ecto-parasite treatment.

 The dogs may be held in kennels for a variable period of time to allow recovery; alternatively some may be released the same day.

 Releasing at the same site at which the dogs were caught.


The logic of this strategy is to replace the existing uncontrolled and potentially dangerous (rabid) population with a neutered and vaccinated one which continues to fill the niche. Thus though the free roaming population may be smaller and controlled, it will still be present. Such a strategy therefore only has application in situations where a free roaming dog population is tolerated (or welcomed) by the community. It is not suitable for all situations (e.g., modern Western cities) and releasing dogs back onto the streets would be considered as abandonment, and so illegal, in some countries.

A reduction in human rabies cases has been used as an argument to justify these programmes. However welcome this trend is, it is likely to be the result of the vaccination component of the strategy rather than the neutering itself.

Potential Logistical and Welfare Problems

CNR programmes are usually instituted on the pretext of improving the welfare of dogs. However, each step of the process can be associated with considerable logistical and welfare challenges.

Catching the free roaming dogs without the active participation of the local community can prove to be problematic. Catching and transportation methods vary in their efficacy and degree of stress caused. More aggressive or cunning dogs will avoid capture and so will continue to breed, perhaps encouraging future generations to retain these undesirable characteristics. The standards of surgical technique are very variable. Clearly compromises have to be made, but there is a minimum standard that must be achieved--below this surgery should not be done at all. This, however, is not always the case and veterinary education remains a real challenge.

The provision of adequate kenneling to hold animals prior to and following surgery is often a limiting factor to the numbers that can be processed. Standards of hygiene and care must be appropriate to prevent additional welfare complications. To avoid the investment in extensive kennel facilities "same-day release" programmes have been introduced. This is acceptable only if there is adequate provision for post-operative monitoring for an appropriate time (sadly not always the case).

When resources are limited, which dogs should be selected? Traditionally, females are done in preference to males as this is considered to have a greater direct impact on the number of puppies produced. Whilst this is logical, leaving larger numbers of males intact may encourage aggression, and the males will still need to be vaccinated. The introduction of non-surgical methods of sterilisation may help with this issue.

It would also be a good use of resources to concentrate on those females that have the greatest chance of reproductive success and whose puppies are more likely to survive. These will be the ones with the best nutrition and so are more likely to be the owned or community dogs rather than the true feral ones. The random capture of free-roaming females may not be the most efficient use of limited resources.

A further question is how many dogs need to be sterilised for the strategy to be effective? The quick answer is a very large proportion! The project managed by the charity Help in Suffering in Jaipur, India, is an example of a well-run programme with population data to assess progress. There is good evidence that the population is now being controlled, but this has taken 10 years of neutering large numbers annually. When resources are limited, aiming to neuter numbers less than the critical threshold will have little long-term impact.

The pressure to neuter large numbers of dogs promotes a mass production culture, and there is a danger when individual animals are considered only as a number that care and welfare may be compromised. The "best vet" is measured in terms of the number of operations performed per day, or the size of the incision, rather than the one whose cases recover quickest or with the minimum of post-operative complications. I believe this philosophy is very important when training colleagues from developing countries--we should be encouraging them to become caring and compassionate clinicians who happen to perform neutering operations rather than robots. The consideration of training also highlights the fact that to be sustainable in the long term the programme must involve the local veterinarians. Importing groups of overseas volunteers for a couple of weeks may be an attractive short-term quick fix, but can never be a long-term solution.

Humane control programmes have been developed to offer an acceptable and effective alternative to mass killing. This does not mean, however, that killing (using humane methods) could not form part of the strategy in some situations. Individual free-roaming dogs that pose a threat to the community (whether from disease or aggression) cannot be left on the street, and culling them may be a realistic option. Reducing the population to a level that can be more effectively managed in the long term may also have some logic.

One final concern is related to the epidemiology of rabies in dogs. A dog infected with rabies virus may be excreting the virus in its saliva for up to two weeks before clinical signs are exhibited. This means that such a dog could be captured, put through the whole programme (including surgery and vaccination), and then released without anybody knowing. This clearly has implications for safety of the staff. There is also a risk that dogs released and identified as being through the system may not be as safe as anticipated and any human cases resulting from these could discredit the whole strategy. A two-step strategy aiming to reduce the risk of rabies by mass vaccination prior to the introduction of population control might reduce this risk.

Changing Hearts and Minds of Community

Animal welfare will only be improved in the long-term by changing the hearts and minds of the local community. Does CNR (in its traditional form) encourage responsible pet ownership? A survey commissioned jointly by WSPA/RSPCA suggested that (in Greece) the presence of a CNR programme in an area might actually increase the incidence of abandonment, and so be counterproductive. The ICAM document stresses the need to engage with the local community--is this possible with traditional CNR? Maybe not, so what modifications to the "traditional" model can be made?

Change in Philosophy of CNR

Traditionally, the acronym CNR stands for catch / neuter / release. As discussed above, this is associated with potential logistical and welfare problems and may even discourage the local community to embrace the concept of responsible pet ownership. It is suggested that the emphasis should be shifted, such that CNR comes to mean collect / neuter / return.

The local community must be persuaded that the aims of any strategy are in their interest. When funds are limited, this may need to be done in a step-wise fashion--concentrating as a priority on those aspects that are the main concern of the community.

In rabies endemic areas this would clearly be reducing the risk of human deaths. This may best be achieved by mass dog vaccination programmes, deferring neutering / contraception to the second phase in order to stabilise the population and make on-going vaccination more sustainable economically. This would not only help to engage the local community, but may also persuade some other major stakeholders (e.g., Health Ministries) to accept the overall strategy--many still consider mass slaughter to be the answer despite the evidence, underlining that education and awareness achieved through the World Rabies Day initiative is aimed at all levels. Controlling rabies prior to the introduction of neutering programmes would improve staff safety as well as reducing the risk that dogs, having been through the programme, could still be released onto the streets while excreting rabies virus and hence be a direct threat to human health.

Implementation of the vaccine programme will identify which dogs are owned or closely associated with people (i.e., suitable for parenteral vaccination) and those that would require oral baiting. Such information is useful to plan future neutering programmes. The prime target would be dogs that are well fed and so are potentially more fertile with improved puppy survival rates. It is likely that a significant proportion of these could be handled by their carers and so brought to the neutering facility, thus avoiding the logistical difficulties of randomly catching dogs. Following some basic education, it would also be possible to return these animals to their carers in the community (same day if appropriate) so a degree of post operative monitoring is assured without the requirement for extensive kenneling facilities.

Perhaps the main long term advantage is that the local community become involved in the care of the dogs and so will be introduced to the concepts of responsible pet ownership, whether at a personal or community level. I believe this is the key to making a real sustainable improvement in welfare in the medium / long term.

Speaker Information
(click the speaker's name to view other papers and abstracts submitted by this speaker)

Ray Butcher, MA, VetMB, MRCVS

MAIN : Animal Welfare : Catch, Neuter & Release
Powered By VIN