Neutering increases the risk of obesity in male dogs but not in bitches - A cross-sectional study of dog- and owner- related risk factors for obesity in Danish companion dogs

By C. R. Bjørnvad, S. Gloor, S. S. Johansen, P. Sandøe & T. B. Lund (2019)
Preventive Veterinary Medicine. Elsevier


Knowledge of risk factors for canine obesity is an important pre-requisite of effective preventative strategies. This study aimed to investigate risk factors for canine obesity in adult companion dogs across Zealand, Denmark.

Client-owned dogs (>2 years of age and without chronic illness) were recruited and examined at eight companion animal veterinary practices in areas with varying socio-economic characteristics. The body condition score (BCS) of the dogs was examined by two investigators based on a 9-point scoring scheme. Dog owners answered a questionnaire that had prompts regarding: 1) dog characteristics, including neuter status, 2) owner characteristics, 3) feeding and exercise practices and 4) the owners’ attachment to the dog. The effect of these factors on BCS and the risk of being heavy/obese (BCS scores 7–9) were analysed in two separate analyses.

A total of 268 dogs were included in the analysis, of which 20.5% were found to be heavy/obese. The average BCS was 5.46. In terms of dog characteristics, neutering dramatically increased both BCS and the risk of being heavy/obese in male dogs but not in bitches. BCS and the risk of being heavy/obese increased in senior bitches and decreased in senior male dogs. The risk of being heavy/obese was higher in dogs with overweight and obese owners. Regarding feeding and exercise practices, providing only one meal per day increased BCS and risk of being heavy/obese. Treats during relaxation increased the risk of dogs being heavy/obese. It also increased the dogs’ BCS, but only if the owners were overweight or obese. An increased duration of daily walking increased the risk of the dog being heavy/obese, but only if the owner was overweight or obese. Allowing the dog to run free in the garden/property decreased the risk of the dog being heavy/obese. The owners’ attachment to the dog was not associated with the dogs’ BCS or dogs’ being heavy/obese.

An important and novel finding was that neutering increased the risk of being overweight or obese for male dogs while bitches were at risk irrespective of neuter status. Furthermore, a complex interaction between owners’ weight status, feeding practices and the risk of dogs being overweight or obese was found, which stresses the need to consider companion animal obesity from a One Health perspective in future prospective studies. Finally, this study was unable to confirm that canine obesity is a product of owners being too attached to their dogs.

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Beyond Castration and Culling: Should we use Non-Surgical, Pharmacological Methods to Control the Sexual Behavior and Reproduction of Animals?

By C. Palmer, H. G. Pedersen & Peter Sandøe (2018) 
Journal of Agricultural and Environmental Ethics
. Springer Nature


This paper explores ethical issues raised by the application of non-surgical, pharmaceutical fertility control to manage reproductive behaviors in domesticated and wild animal species. We focus on methods that interfere with the effects of GnRH, making animals infertile and significantly suppressing sexual behavior in both sexes. The paper is anchored by considering ethical issues raised by four diverse cases: the use of pharmaceutical fertility control in (a) male slaughter pigs (b) domesticated stallions and mares (c) male companion dogs and (d) female white-tailed deer. Ethical concerns explored include animals' welfare, the possible violation of animals' rights, including rights to life, reproduction and bodily integrity; and potential concerns about loss of wildness. We compare ethical concerns about pharmaceutical fertility control with alternative strategies for managing animals' reproductive behavior including (where appropriate) spaying and neutering, sex separation, sex sorting, culling, and doing nothing. The paper concludes that there are some cases where pharmaceutical fertility control is the best ethical choice in current circumstances; but that there are other cases where alternative choices, including doing nothing, would be ethically preferable. This suggests that in ethical terms a case-by-case approach should be taken to the use of pharmaceutical fertility control in animals.

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Inconvenient Desires: Should We Routinely Neuter Companion Animals?

By C. Palmer, S. Corr & P. Sandøe
Anthrozoös. Berg Publishers. 2012


Influential parts of the veterinary profession, and notably the American Veterinary Medicine Association, are promoting the routine neutering of cats and dogs that will not be used for breeding purposes. However, this view is not universally held, even among representatives of the veterinary profession. In particular, some veterinary associations in Europe defend the view that when reproduction is not an issue, then neutering, particularly of dogs, should be decided on a case-by-case basis. However, even in Europe the American view is gaining ground. In light of this situation, this paper considers whether or not routine neutering of cats and dogs, in cases where uncontrolled reproduction is not an issue, can be ethically defended.

The starting point of this consideration is a review of the veterinary literature on the effects of neutering on companion animals. The focus is both on the welfare of neutered animals themselves, and on behavioral and other effects that may not directly affect the animals' welfare, but that may be motivating factors for owners to neuter their companion animals. Here it becomes clear that justification for routine neutering, particularly of confined male dogs, does not follow from claims about the dogs' own welfare. The costs of neutering male dogs, in terms of the increased risk of very serious diseases, may well outweigh the benefits. Then, building on this veterinary material, but including some other, additional considerations, the paper goes through some possible ethical approaches to routine animal neutering. These ethical approaches offer different degrees of concern about, or opposition to, routine neutering. Finally, based on this ethical exploration, it is argued that routine neutering, at least in the case of non- free-ranging companion animals, raises significant ethical questions, and from some ethical perspectives, looks highly problematic.

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