“Elimination (urination and defecation) is one of the fundamental biological activities of any species” (Wagner et al 2014). Maslow's(1943) hierarchy of needs, places elimination as a basic physiological need and a requirement for survival . Therefore a dog has a drive to urinate. However there is a whole lot going on in the dispersal behaviour of urine over and above the simple elimination of waste.
New born puppies urination depends on an exteroceptive somato- bladder reflex mechanism that is triggered when the mother licks the genital or perineal regional of the pup, this reflex diminishes as voluntary neural pathways develop between 7-12 weeks old ((animals with spinal injuries can be manipulated to urinate through this exteroceptive- somato reflex mechanism) (Fowler 2008). So it should be no surprise when a puppy under 3 months old eliminates shortly after someone picks them up because they have accidently stimulated this reflex.
Mature bladder function can be represented as a cycle, made up by a series of phases: Filling; desire to void; postponement; initiation of sphincter relaxation; and bladder contraction; and maintenance of both these until the bladder is empty/filling. To make use of the postponement phase three abilities are required:
to appreciate what is an acceptable micturition site;
to be able to get there;
and to adopt a micturition posture.
Each phase and each requirement in the postponement phase has its own disorders which may occur alone or in various combinations (Yeates 1974).
The desire to micturate and the symptom of urgency is produced by an increase in tension in the bladder wall, attenuated by bladder contractions. The contraction waves and resulting sensations are easily affected in either direction by cortical activities. Micturition is normally initiated by voluntary removal of its inhibition, then urination results from inhibition of the tone of the striated muscles in the pelvic floor. Therefore maturation of the control of micturition consists of reduction of the micturition reflex; development of consciousness bladder distension; and the development of conscious ability to postpone or to initiate micturition as required (Yeates 1974).
So it is important to think about the developmental stage of the dog understand that there is individual variation in bladder control age, and also to take note that there is variation in bladder size even between dogs of same breed and same age( Mantis 2008).
Over the last century scientists have studied elimination behaviour of various species including domestic dogs. Ross (1950) studied elimination behaviour of dogs under the specific conditions living conditions in laboratory colonies, where dogs existed in living-eating- sleeping quarters. It was identified that adult dogs preferred to eliminate away from the sleeping and eating areas, and selected a restricted area, and eliminated in that particular area daily. If house broken, they
preferred to eliminate outside, despite the requirement for more effort to be made to go outside. If dogs were disturbed by strange noises or by continued presence of observer the restricted behaviour of elimination was not continued.
Preferred elimination away from bed and food areas appears to be normal species specific behaviour which is not just confined to domestic dogs, other animals also have preferred locations away from food and bed area (Jenson 2002).
Puppies ceased eliminating in bed area around five weeks old, but do not develop selection and restricted elimination behaviour for another few weeks (Ross 1950; Wagner et al 2014). This is the time where voluntary neural pathways are being developed and where elimination behaviour begins to be learnt.
Identifying the site of elimination might well identify the reasons for inappropriate elimination, if the dog is eliminating in one area it is likely his preferred restricted site a sign that house training might have gone wrong, the dog has learnt indoor location and substrate preference (Beaver 2009). However Ross 1950 and Wagner et al 2014 identified that if a dog eliminates in one area the likely hood of another dog or the same dog eliminating in that area is high. So the elimination might have started as an accident, but if the smell is still in that area the dog is more likely to eliminate in that area again and as a result learns his preferred elimination site.
Often puppy owners use puppy pads inside the house, the pup learns to urinate on the puppy pads. Owners remove puppy pads without any further training, and the dog eliminates on the carpet instead because he has learnt that he can urinate in the house, and the
carpet feels just the same as a puppy pad to the dog.
If the dog has no preferred site and is urinating here there and anywhere the dog has either not developed preferred elimination areas, or is anxious or is continuously being disturbed by someone or something.
Anxiety can suppress bladder contraction waves or conversely exaggerate bladder contraction waves (Yeates 1974).
Weber (1939) suggested that providing a restricted crate with no more room than to lie down would ensure that the dog would inhibit defecation and urination in the cramped conditions, and many people still use this method of house training today. However leaving a dog in his crate for long periods without providing the chance to eliminate in appropriate areas, results in the overriding drive to urinate which is counterproductive because the dog learns that he has no choice but to
urinate in his crate area.
Physiological reasons (this list is not exhaustive):
The dog is in pain
Obesity is a common risk factor for incontinence in dogs.
Neutering is also one of the primary risk factors for incontinence, however, most animals do not develop any medical disorders as a result of neutering; complications are uncommon. If there is incontinence related to neutering, it will generally be temporary, as the dog learns to control its urinary muscles again during the recovery process (De Bleser 2011; Beauvais 2012) .
Disruption of the nerves around the bladder
Lesions in the brain
Damage to dogs nerves or spinal cord that innervate the bladder, trauma or neoplasia
Overactive bladder syndrome
Urinary tract infections
Chronic inflammatory disease
Pressure on the bladder caused by a mass
Underdevelopment of the bladder or other birth defects
Decreased sphincter control often seen in older females
This list as stated is not exhaustive but it shows how important it is to ensure that there is not a physiological reason for inappropriate elimination (Maddison et al 2008).
Medical reasons (the list is not exhaustive)
Diabetes, Cushings disease, Addisons disease, Hyperthyoidism, Hypercalcemia, Hypokalemia, Liver disease, generally due to
increased thirst and increased urine output ( Maddison et al 2008).
Kidney failure (maddison et al 2008)
ureta stones (Dalmations have a genetic mutation which interferes in uric acid transportation resulting in an increased risk of urate
stones) (Fascetti et al 2012),
Cancer within the urogenital system (Maddison et al 2008).
Epilepsy (Maddison et al 2008; Overall 2013).
Canine cognitive dysfunction (Osella et al 2007).
Pharmacological causes:
Steroids generally cause increase in thirst and consequently urination (Maddison et al 2008)
Cholinergic drugs like acetylcholine, produce an urgent desire to void, and is associated with a bladder contraction wave. And anti cholinergic drugs decrease the desire to void (Maddison et al 2008, Yeates 1974). Diuretics causes increase in urination due to their effect of ridding the body of excess water (Maddison et al 2008).
Anticonvulsants usually due to increase in thirst resulting in increase in urination, however Anti convulsants can cause overflow urination, due to their depressive effects on the nervous system, dogs might not feel that their bladder is full and become incontinient ( Maddison et al 2008)
Antihistamines and antipsychotics which contain phenothiazine can cause increase in thirst and consequently increase in urination (Maddison et al 2008)
As a result of choosing just a few pharmacological products it shows how important it is to know what medications or over the counter supplements a dog is taking to identify if that is a likely candidate of causing inappropriate elimination.
If the dog is fearful of being outside he could hold onto his urine and only eliminate where he feels safe the house being his safe place to urinate.
If the dog is excited or absorbed in investigating his outside environment he might forget to eliminate outside, due to his other drives being more important at the time, then when the dog comes in to the house he has a full bladder and is then driven to urinate to reduce his discomfort.
If the dog is excited on homecomings he can urinate in the house this is a result of the activation of the entire autonomic nervous system in co- release resulting in the dog eliminating on greetings the same occurs in submissive weeing (Jenson 2002).
Male dogs are more likely to cock their legs on upright surfaces, particularly if, they are new items being brought in to the house hold. For some dogs this is way of making it smell like it belongs here, for other dogs, novel items in the household are a subject of anxiety and are likely to cause an increase in inappropriate elimination.
As highlighted by Ross (1950) any disturbances in their environment can cause the dog not to eliminate in their preferred area, so a house trained dog who starts to eliminate in the house, a likely candidate is a change in their environment, whether that is a new neighbour, new house, new resident dog or other pet, new baby, change in work schedules, change in feeding and exercise routines, building renovations, decorating, new carpets etc.
Dogs with separation anxiety have an increase in likelihood of eliminating when owners are absent.
Some dogs do not like eliminating in front of owners, and find it difficult to urinate whilst on lead. Occasionally this is caused by owners punishing the dog for urinating or defacating inappropriately, however for other dogs they have a bashful bladder in much the same way as humans suffer from Paruresis (unable to urinate in public) and as a result they come in from being outside and go under the coffee table and urinate. Dogs need to feel safe to eliminate whether that it is urine or
faeces. If they do not feel safe outside they are likely to eliminate where they feels safe and that being indoors.
To sum it all up, individual dogs develop at different rates, some dogs have small bladders some have a larger bladders. Some learn quickly and learn appropriate preferential substrate with little guidance, some dogs need me guidance than others. Some dogs are more anxious than others, some dogs are more busy than others. You hear that pups are housetrained at 8 weeks old, this is a bit farfetched, what it actually means is that there has been good husbandry and the pup has been guided to the appropriate elimination site at the right time. My personal opinion is that dogs are not reliably house trained until they are at least a year old, and even then if the dog has to rely on owners for his elimination needs, without good husbandry the dog can eliminate anywhere.
References
Beaver, B (2009) Canine Behavior: Insights and Answers . 2nd edition. Saunders, an imprint of Elsevier Inc.
Beauvais W, Cardwell J M, Brodbelt D C (2012). The effect of neutering on the risk of urinary incontinence in bitches – a systematic review, Journal of Small Animal Practice 53: 198-204.
De Bleser B, Brodbelt D C, Gregory N G, Martinez T A (2011). The association between acquired urinary sphincter mechanism incompetence in bitches and early spaying: a case-control study, The Veterinary Journal 187: 42-47.
Fowler, C. Griffiths, D. de Groat, W. (2008) The neural control of micturition Nature Reviews: Neuroscience 2008 June; 9(6): 453–466
Jenson,P. (2002) The Ethology Of Domestic Animals CABI publishing Oxon: UK. New york: USA
Maddison, J. Page,S. Church, D. (2008) Small animal clinical pharmocology. 2nd edition. Saunders elsevier: USA.
Mantis, P. (2008) Ultrasonography of the Urinary and Genital System of the Dog and Cat. 2nd International Symposium of Veterinary Surgery and 7th Iranian Symposium of Veterinary Surgery, Anesthesia and Radiology, Kerman, Iran, 21-24 April, 2008. Iranian Journal Of Veterinary Surgery 2008 No. Supplement 2 pp. 63-71
Maslow, A. (1943) A Theory Of Human Motivation Psychological Review Vol :50 no : 4 pp 370-396.
Osella,M. Re,G. Odore,R. Girardi,C. Badino,P. Barbero,R. Bergamasco,L. (2007) Canine cognitive dysfunction syndrome: Prevalence, clinical signs and treatment with a neuroprotective nutraceutical Applied Animal Behaviour Science Volume 105, Issue 4, July 2007, Pages 297–310
Overall, K. (2013) Manual of clinical behavioural medicine for dogs and cats. Mosby and imprint of Elsevier Inc: Canada.
Ross, S. (1950) Some Observations on the Lair Dwelling Behavior of dogs. Behaviour, Vol. 2, No. 3 (1950), pp. 144-162
Wagner, D. Newbury, S. Kass, P. Hurley,K. (2014) Elimination Behavior of Shelter Dogs Housed in Double Compartment
Yeates WK. (1974) Neurophysiology of the bladder. Paraplegia ; 12: 73–82
