Number one vs. number two?

We often get queries from clients about what to do when they see their pet straining.  Some things we may need to know are if the animal is straining to pass urine or faeces (which can sometimes be a tricky question to answer), is the animal a girl or a boy, and how long they have been straining for.


This photo shows a severely constipated dog.  The red arrows show the large amount of faeces in the colon and the orange arrow shows spinal arthritis, likely a contribution factor to the degree of constipation.

"Number Ones"

The inability to urinate can be life-threatening.  The bladder fills like a balloon and can eventually pop or become overstretched so that the nerves in the bladder wall no longer work.  Before these scenarios, electrolyte imbalances can occur, resulting in vomiting, dehydration, heart irregularities and an increased breathing pattern.

Some animals show obvious signs of difficulty by squatting or lifting their leg with nothing coming out.  Some can vocalise whilst straining (cats will yowl) and some may show large tummy contractions to push something out, without result.  However sometimes the signs aren't so obvious; the pet may just act out of the ordinary or become lethargic.  Some signs mimic those of a urinary tract infection by the animal urinating little and often or licking at themselves excessively because they are irritated.  A physical examination of the animal is necessary to determine whether it is inflammatory irritation to the bladder, or a true blockage.  Other tests may be indicated such as x-rays, blood tests, intravenous fluids, urinary catheterisation and sometimes surgery.

Boys have a smaller urethral diameter than girls which means, if a bladder stone is the culprit, a girl is more likely to pass the stone whereas a boy is more likely to get a stone stuck in the urethra.  However both sexes can get a stone stuck in the outlet area of the bladder.  Male cats can get a crystallised or mucous plug at the end of the urethra preventing urination also.

In boy dogs prostatic enlargement can be driven by hormones or can be a result of cancer.  The prostate sits between the colon and the urethra and if the prostate is large enough it can put downwards pressure on the urethra, effectively squashing it. 

Other causes for urinary difficulties may be bladder or urethral cancer and spinal or pelvic injuries can result in bladder nerve injury.  Trauma, foreign body, perineal hernia or dystocia in a pregnant bitch or queen can also result in urinary problems.  A badly constipated animal may also have urinary issues, whereby the faeces have become so large that they are compressing down on the urethra.  In this instance - the animal cannot pee or poo.

"Number Twos"

Animals will commonly present as straining but not producing anything.  This can be a truly constipated dog or it may be mimicking another condition and a physical examination is required to get to the bottom of the problem (pun intended).

Anal gland concerns can mimic the signs of constipation.  The animal may look to be straining, licking at themselves or scooting their bottoms along the ground.  The anal glands are scent marking glands which sit in the rectal wall and their purpose is to coat faeces with the scent of the dog as a way of marking territory.  These glands can become blocked or infected, and then they sit like marbles which can irritate the animal.

Large bowel diarrhoea may be mistaken for an animal trying to strain to pass faeces but in fact it is passing something, just little and often and usually runny.

Bones, carcasses, scraps, plastic bags and other foreign material can be contributing factors in the constipated dog.  Dehydration can either contribute to, or result from, constipation.  It can be an expensive procedure to unblock the severely constipated animal and intravenous fluids are required to rehydrate the animal and try to soften the faeces.  Sometimes a full general anaesthetic is required so that an enema can be given to help break up the rock-like material, and animals can be very sore afterwards.

Animals which have received pelvic injuries from road traffic trauma can end up with narrowed pelvic canals which can affect the ability of an animal to pass a normal sized poo.

Prostatic disease can contribute to ‘pooing problems' by putting pressure upwards and compressing the colon.  If an animal has an enlarged prostate as a result of the dog being an entire male then we may recommend de-sexing as a solution to urinary and faecal problems.

Unfortunately some animals have repeat issues with constipation.  In some instances this may be attributable to spondylosis (arthritis of the spine) or lumbosacral spinal disease - both of which make posturing to defecate difficult.  This can be a double-edged sword, with the nerves involved in moving the bowel no longer working properly, and the wider the diameter of the colon meaning the larger the size of the poo which can accumulate.  

Going "number ones and twos" is an important part of life.  If there is doubt that your pet is toileting properly then contact us without delay.