Calico and Tortie Cats – What is the Difference?

What are calico and tortie cats?

Calico and tortie (tortoiseshell) are both common coat colours/patterns which appear almost exclusively in female cats. The terms calico and tortie are often used interchangeably, and it is easy to see why. Both patterns refer to a multi-coloured cat which may consist of black and orange, brown and orange, grey and cream with or without white.

Read moreCalico and Tortie Cats – What is the Difference?

Why Do Some Cats Have A Tattoo in Their Ear?

A black or green tattoo on the inner portion of a cat’s ear is to show that the cat has been desexed (spayed or neutered). The veterinarian adds the tattoo during spay/neuter surgery.

Do all veterinarians and rescue centres tattoo cat ears?

Not all cats who have been desexed will have a tattoo, only one out of my four has an ear tattoo.

Ear notches

Notch in feral cat's earTrap, neuter & return (TNR) feral cats may have a notch out of their ear instead of a tattoo. Due to their fear of humans, the ear notch makes it easy to determine if the cat has been desexed from a distance.

You can see in the photo the tip of the cat’s ear has been removed, some veterinarians will remove a portion of the ear from the side instead of the tip. This procedure is carried out during the spay/neuter operation. While tattoos work for tame cats, they can be hard to see from a distance on feral cats. Which makes the notch a more reliable option.

Can pet owners tattoo cats?

Laws can vary from country to country and region to region, but most places would consider tattooing or piercing animal abuse. While adults can make an informed choice, cat’s can’t and pet owners run the risk prosecution for tattooing a cat. The ear tattoo serves a useful purpose and is performed on the cat under anesthesia, cosmetic tattoos serve no useful purpose.

How to determine if a cat has been spayed or neutered

Entire vs neutered maleNot all cats have an ear tattoo or notch to easily identify a desexed cat. When a male cat is neutered (orchidectomy), an incision is made in the scrotal sac and the testicles are removed, leaving the sac intact. This makes it easy to identify a neutered male. The only exception is if the male is cryptorchid, which means one or both of the testicles hasn’t descended into the scrotum, which can give the appearance of a neuter.

Other identifying clues include the presence of barbs on the penis of males who were neutered before six months and stud jowls on entire adult males.

Stud jowls on an entire male cat
Stud jowls on an entire male cat

It can be more difficult to determine if a female cat has been spayed which necessitates shaving the fur to look for a spay scar. Females may be spayed midline or flank, so if a scar cannot be found midline, then a second patch of fur will be shaved. The absence of estrus (heat) is another good clue that the female has been desexed. Entire cats will have repeat heat cycles until or unless she mates. During estrus, the female will roll on the ground, or if touched along the back close to the tail, will assume a mating position with the front part of her body low, and the rear half raised. 


Does A Cat’s Eyesight Decline With Age?

As I work in human eyecare and we are fast approaching the year 2020, there is an increasing focus (pardon the pun) on 20/20 vision along with bad jokes. But what exactly is 20/20 vision and do cats experience a decline in vision the way humans do?

Visual acuity refers to the clarity of vision, and 20/20 vision means that the test subject can see the same line of letters at 20 feet as a person with normal vision can see at 20 feet. People of all ages (including young children) can have refractive errors, which occur when the eye cannot focus properly, and they will find it hard to see close up (farsighted or hyperopia) or distance (near-sighted or myopia).

One of the most common types of refractive errors occurs as people move into their late 30s and early 40s. Many will notice a decline,  usually with their close up vision. They find it hard to read text on their phones, or menus; this type of refractive error means they are farsighted (presbyopia) due to age.  The decline in the ability to focus due to age develops because the lens, which sits behind the pupil loses its ability to change shape and properly focus light on the retina located at the back of the eye. Optometrists can correct refractive errors with glasses or contact lenses.

Refraction errors

If you have ever seen an optometrist write a script, he or she will use numbers which tells the optical dispenser what strength to supply the lenses (or contacts). The power of the lenses necessary to correct your vision is measured in units called diopters which go up or down units of 0.25. Plano is the fancy term for 0.00, which means there is no refractive error. Most sunglasses off the shelf have plano lenses, and we might order a plano lens for a patient who has recently had cataract surgery on one eye, or somebody who wants to order coloured contact lenses.

This is how a script may look, for the ease of simplicity, I won’t go into astigmatism or axis.

  • +2.25 (right eye)
  • +2.50 (left eye)


  • -1.75 (right eye)
  • -2.25 (left eye)

The plus is used for people who are farsighted and the minus for people nearsighted.

Do cats develop refractive errors as they age?

There is very little information on refractive errors in cats. One small trial of 98 healthy cats did show refractive errors in cats and kittens. Younger cats had greater negative refractive errors (shortsighted) than adults but generally progressed to emmetropia (normal vision) during adulthood. Most adult cats are neither shortsighted or farsighted.

How cats see the world

Even cats who do have normal vision won’t have 20/20 vision in the way we do. Cats are not small people and their eyes have evolved for hunting in low light.

  • Cats have elliptical pupils which can expand considerably to let in more light from dusk to dawn
  • A greater number of cones which assist with peripheral and night vision but fewer rods than people means their ability to see colour and fine detail is limited.
  • The tapetum lucidum is a layer of reflective tissue which lies directly behind the retina and acts as a mirror to reflect light back through the retina. If the light misses a rod, it will reflect off the mirror layer of the tapetum lucidum and be bounced back, which provides the photoreceptor cells with a second opportunity for photon-photoreceptor stimulation, thereby enhancing visual sensitivity at low light levels.
  • The cat has a large lens which enables it to gather more light, but the cat’s lens is less able to change shape and focus over different distances than that of the smaller human lens which means that cats cannot see extremely close objects. The small human lens gives us a large depth of focus.

So, no glasses or contact lenses for cats?

While refractive errors are not common in cats, contact lenses do exist for cats with corneal ulcers. The contact lens (known as a bandage contact lens) goes over the cornea to relieve pain and allow the cornea to heal.

 Vision loss in older cats

While refractive errors aren’t an issue in cats, vision problems can develop. The most common cause of vision loss is due to cataracts which occur when the normally transparent lens of the eye becomes opaque, which reduces the amount of light which reaches the retina. Cats of any age can develop a cataract, but they are most common in middle-aged to senior cats. Surgery may be recommended to replace the lens and replace it with an intraocular lens. Where surgery isn’t an option (due to the age of the cat, financial reasons) conservative management can include restricting the cat inside and maintaining a normal routine which includes avoiding moving things around. Cats adapt well to vision impairment.

Retinal detachment (RD) is a common, severe and sight-threatening disorder which occurs when the retina lifts or pulls away from the underlying retinal pigment epithelium due to a tear in the retina. This allows vitreous, a gel-like substance which gives the eye its shape to leak through the tear which causes the retina to separate from the underlying tissue. High blood pressure (often a side-effect of chronic kidney disease), hyperviscosity syndrome, glaucoma, advanced diabetes and trauma can all lead to a retinal detachment.

Types of Tabby Patterns & Colours in Cats

Ginger and brown tabby cats

At a glance

What is a tabby cat?

Tabby is a coat pattern and not a breed, it consists of four patterns, mackerel, spotted, classic and ticked. The background hair consists of light and dark bands, intermingled with dark lines, spots or swirls layered on top.

What colour is a tabby cat?

Tabby occurs in several colours, the most common are brown tabby, silver and orange tabby.


Tabby refers to a coat pattern in cats which consists of dark swirls, stripes, spots superimposed on a lighter background of ticked (banded fur).

The banded background (ground colour) consists of hairs which are more than one colour along the hair shaft and is termed agouti. This is caused by the transient inhibition of pigment production during, the hair’s growth.

Agouti and non-agouti pattern on hair shaft

The agouti gene controls whether the tabby pattern is expressed or not. The dominant agouti allele, with the symbol A will express the tabby pattern. The recessive a ‘hides’ the tabby pattern, to produce a solid (self) coat colour from the root of the hair to the tip. A cat must receive two copies of the recessive a gene (aa) to have a solid coat.

Three possible outcomes dictate if the coat will be tabby or not, remembering that the cat receives a copy of each gene from the mother and the father.

  • A/A (homozygous dominant) – Tabby
  • A/a (heterozygous dominant) – Tabby (the dominant A will override the recessive a)
  • a/a (heterozygous recessive) – Non-tabby (solid)

The tabby pattern is common in random-bred cats as well as many pure breeds. All domestic cats were once tabby, mutations lead to some cats appearing solid, bi-colour or pointed. Even cats with no tabby stripes have tabby genes but do not show the pattern on the fur. Some young cats with solid coat colours will display faint ghost tabby patterns until their fur becomes fully pigmented.

Ghost tabby pattern on tuxedo kitten
You can see a faint ghost tabby pattern on the body of this tuxedo kitten.

The basic wild-type tabby is a mackerel (Tm); however, two mutations have arisen, the dominant ticked tabby (Ta) and the recessive classic tabby (tb).

Basic cat genetics

Cats have 19 chromosomes which come in pairs, one from the mother and one from the father. 18 of the chromosomes are autosomes, and one pair are the sex chromosomes X and Y. All of the female cat’s eggs are X, whereas the male sperm can be X or Y. If an X sperm fertilises the egg, the offspring will be female (XX), if a Y sperm fertilises the egg, the offspring will be male (XY).

Genes are contained within the chromosome which is made up a double-strand helix containing DNA. DNA contains the instructions necessary for the cat to develop, survive and reproduce. For this to occur, the DNA has to be converted into messages which can be used to produce proteins, that are complex molecules that do most of the work within the cat’s body.

A locus (plural loci) is the specific, fixed position on a chromosome where a particular gene or genetic marker is located.

Alleles are variants of the same gene, for example, B (black), b (chocolate) and b1 (cinnamon).


Coat colours

Tabby cat colours

The tabby coat occurs in many colours, primarily silver, brown and red (ginger/yellow). But a dilution can change those primary colours into lighter forms.

Melanocytes are cells responsible for producing melanin, which are microscopic granules occurring in the hair, skin, and iris of the eyes. The size, shape and arrangement of melanin granules are responsible for the colour of the cat’s coat. Cats have two types of melanin, black-based eumelanin and orange-based pheomelanin. Eumelanin are spherical and absorb almost all light, which gives black pigmentation, pheomelanin granules are elongated and produce the red coat colour.

The black gene has three alleles which control the density of eumelanin in the hair shaft.

  • B produces black fur and is dominant
  • b reduces melanin density to a chocolate colour
  • b1 which further reduces melanin density to a medium brown (cinnamon)

Red based colours have two alleles which are located on the X chromosome.

  • O produces red fur
  • o (non-orange) produces black fur


Dilute classic tabby munchkin cat

Dilute classic tabby munchkin cat[/caption]

Dilute coat colours are a recessive trait which dilutes coat colours by causing uneven distribution of pigment in the hair shaft

  • Black dilutes to blue (grey)
  • Chocolate dilutes to lilac
  • Cinnamon dilutes to fawn
  • Orange dilutes to cream

Dilute modifier (DM)

A secondary type of dilution known as dilute modifier can also occur, which causes the coat to take on a brownish cast. The dilute modifier only affects dilute colours and has no effect on dense colours.

  • Blue becomes caramel
  • Chocolate becomes taupe
  • Cream becomes apricot

White spotting gene

Brown tabby and white cat

Some tabby coats have some white fur, usually on the paws, belly, chest, throat and sometimes face. This white fur is caused by the white spotting gene (S). Genetically, the cat is tabby, but the white spotting gene masks the colouration on certain parts of the body.

Tabby patterns

Mackerel tabby

Mackerel tabby

Also known as striped, the mackerel tabby pattern is the dominant wild-type which consists of well-defined, evenly spaced thin vertical stripes on the sides of the body which extend from the shoulder to the tail, and a paler ground colour.

Spotted tabby

Spotted tabby cat

The spotted coat is a variant of the mackerel tabby however a modifier gene breaks the characteristic mackerel stripes up into spots.

Classic tabby

Silver classic tabby

Also known as blotched or marbled, the classic tabby coat pattern consists of dark whorls on a lighter background. The ideal classic tabby will have a bullseye or oyster mark on each flank. The classic tabby is recessive to the mackerel tabby.

When viewed from above, the shoulders of a classic tabby have the appearance of a butterfly, and the classic is sometimes referred to as a butterfly tabby.

Oyster mark on classic tabby


Silver classic tabby

Ticked tabby

Ticked tabby cat

Also known as Abyssinian tabby, the ticked tabby has a gene which hides the tabby striping, leaving only the underlying agouti colouration. There is little to no striping on the body, but some faint fine barring may be present on the face, legs and tail, this may be more apparent if the cat is heterozygous, meaning its genetic makeup is Ta/Tm or Ta/tb

Tabby M

M marking on a tabby cat

All tabby cats, regardless of pattern or colour, have a characteristic M on their forehead and most will have additional lines around the eyes. The ticked Singapura has cheetah lines, which extend down the face from the inner corner of the eyes.


What cat breeds can have the tabby coat pattern?

  • Abyssinian
  • American bobtail
  • American curl
  • American shorthair
  • American wirehair
  • Australian mist
  • Bengal
  • British shorthair
  • Cornish Rex
  • Devon Rex
  • Egyptian Mau
  • Exotic
  • Maine coon
  • Munchkin
  • Ocicat
  • Oriental
  • Persian
  • Scottish fold
  • Scottish shorthair
  • Siamese (lynx point)
  • Singapura
  • Somali
  • Toyger


Do tabby cats have striped skin?

Tabby cats do not have striped skin, interestingly, tigers do.

Are tabby cats a breed?

Tabby is a pattern and not a breed of cat.

Is the tabby gene dominant?

The tabby pattern is dominant over solid.

Are tabby cats male or female?

The tabby pattern can be found on both male and female cats, however, the ratio of ginger males to females is 3 -1. That is because the female must inherit the red gene from both mother and father for her to be ginger, if she inherits one red gene and one black gene (or brown), she will be tortoiseshell. Some females also carry the white spotting gene, which will make her a calico or a torbi. Tortoiseshell and calico cats have a solid colour (usually black), intermingled with red, others show both brown tabby and red tabby.

Why does the female have two tabby colours but not the male?

The female inherits a copy the red gene located on the X chromosome from one parent and a non-red gene from the other parent. X-inactivation or lyonization occurs during early development (around the eight-cell stage, but it can occur later) to prevent the expression of both X chromosomes. Every cell in the female has one active and one silenced X chromosome (known as a Barr body), and as the cells continue to divide, they will take the colour from those eight progenitor cells. The earlier the inactivation, the larger the patch of fur derived from each lyonized progenitor cell.

Lyonization in cats

Below is a photo of a calico cat, you can clearly see the brown and red tabby colours as well as the effects of the white spotting gene. Tortoiseshell and calico are rare in male cats because they only have one X chromosome, so they will either be ginger or non-ginger. Occasionally a male will be calico or tortoiseshell, the incidence is reported to be 1 in 3,000, these males are almost always infertile.

Calico domestic cat


Christmas Food Guidelines For Cats (Safe & Toxic List)

Christmas turkey

For many, part of the enjoyment of Christmas is time spent with family and friends over Christmas lunch or dinner. As pet owners, we want to include our cats in the festivities, but not all food is safe for cats to eat. We take a look at common Christmas foods which are safe or dangerous for cats.

When it comes to food, moderation is the key. Treats should make up no more than 10% of a cat’s diet as they are not complete and balanced and many contain empty calories.

Read moreChristmas Food Guidelines For Cats (Safe & Toxic List)

Cat Themed Health and Awareness Days – January to December 2020

Cat health and awareness days 2020

January 2020

  • 2nd January – Happy Mew Years Day
  • 2nd January – National Pet Safety Travel Day (US)
  • 14th January – National Dress Up Your Cat Day (US)
  • 22nd January – Answer Your Cat’s Question Day
  • 24th January – Change a Pet’s Life Day
  • Glaucoma Awareness Month
  • Thyroid Awareness Month (US)

February 2020

  • 4th February – World Cancer Day
  • 14th February – Pet Theft Awareness Day
  • 18th – 24th February – National Drink Wine With Your Cat Week (US)
  • 20th February – National Love Your Pet Day (US)
  • 25th February – World Spay Day
  • 29th February – Rare Diseases Day
  • Pet Dental Health Month
  • National Cat Health Month
  • Responsible Pet Owners Month
  • National Prevent a Litter Month (US)
  • Spay/Neuter Awareness Month

March 2020

  • 8th March to 14th March – World Glaucoma Week
  • 12th March – World Kidney Day
  • 13th March – World Sleep Day
  • 20th March – World Oral Health Day
  • 28th March – Respect Your Cat Day
  • Responsible Pet Owners Month
  • Professional Pet Sitters Week (first week in March)
  • National Poison Prevention Week (third week in March)
  • Melanoma March (Australia)

April 2020

  • 1st April to 7th April – International Pooper Scooper Week
  • 4th April – World Stray Animals Day
  • 6th April – National Siamese Cat Day (US)
  • 7th April – World Health Day
  • 11th April – National Pet Day (US)
  • 17th April – World Hemophilia Day
  • 18th April – Pet Owners Day
  • 19th April – World Liver Day
  • 24th April – Hairball Awareness Day
  • 26th April – National Pets and Kids Day (US)
  • 27th April – World Veterinary Day
  • April 28 – National Pet Parents Day (US)
  • 30th April – National Adopt a Shelter Pet Day (US)
  • 30th April – National Tabby Day (US)
  • National Pet Month (US)
  • Prevention of Cruelty to Animals Month (ASPCA)
  • National Heartworm Awareness Month (US)
  • National Pet First Aid Awareness Month (US)
  • Oral Cancer Awareness Month

May 2020

  • 2nd May – World Asthma Day
  • 5th to 11th May – Be Kind to Animals Week
  • 11th May – National Animal Disaster Preparedness Day
  • 17th May – World Hypertension Day
  • 20th to 26th May – National Volunteer Week (US)
  • Thyroid Awareness Month (Australia)
  • Chip Your Pet Month
  • Arthritis Awareness Month
  • Food Allergy Action Month
  • National Pet Month (US)

June 2020

  • June 1 to 7 -Pet Appreciation Week
  • 4th June – World Hug Your Cat Day
  • 9th June – World Pet Memorial Day
  • 22th June – Take Your Cat to Work Day
  • 19th June – National Garfield the Cat Day
  • 24th June – Cat World Domination Day
  • Adopt a Cat Month
  • National Microchipping Month (US)
  • Cataract Awareness Month

July 2020

  • 5th July – National Pet Remembrance Day (UK)
  • 6th July – World Zoonoses Day
  • 14th to 20th July – National Diabetes Week (Australia)
  • 12th July – National Different Coloured Eyes Day (US)
  • 15th July – National Pet Fire Safety Day (US)
  • National Lost Pet Prevention Month (US)
  • National Pet Hydration Awareness Month (US)

August 2020

  • 8th August – World Cat Day
  • 15th August – Check the Chip Day
  • 17th August – National Black Cat Appreciation Day
  • 17th August – International Homeless Animals Day
  • 22nd August – National Take Your Cat to the Vet Day
  • 28th August – Rainbow Bridge Remembrance Day
  • National Immunization Awareness Month – (US)

September 2020

  • 1st September – Ginger Cat Appreciation Day
  • 13th September – National Pet Memorial Day (US)
  • 16th September to 22nd September – Adopt-a-Less-Adoptable-Pet Week
  • 23rd to 29th September – National Eye Health Week (US)
  • 25th September – International Ataxia Awareness Day
  • 27th September – World Deaf Day
  • 28th September – World Rabies Day
  • 29th September – World Heart Day
  • 29th September – Beckoning Cat Day
  • Pet Sitter Education Month
  • National Pet Memorial Month (US)
  • Happy Healthy Cat Month
  • Animal Pain Awareness Month

October 2020

  • 1st October – CATober – Universal birthday of shelter cats
  • 4th October – World Animal Day
  • 4th to 10th October – National Animal Shelter Appreciation Week (US)
  • 11th October – World Obesity Day
  • 13th to 19th October – National Veterinary Technicians Week (US)
  • 16th October – National Feral Cat Day (US)
  • 27th October – National Black Cat Day (US)
  • 29th October – National Cat Day (US)
  • Breast (Mammary Gland) Cancer Awareness Month
  • First week of November – National Animal Shelter Appreciation Week (US).
  • National Pet Wellness Month (US)
  • National Animal Safety and Protection Month (US)

November 2020

  • 17th November – National Black Cat Day (Italy)
  • Responsible Pet Owners Month
  • Adopt a Senior Pet Month
  • National Senior Pet Month (US)
  • Pet Cancer Awareness Month
  • Pet Diabetes Month

December 2020

  • 5th December – International Volunteer Day
  • 10th December –  International Animal Rights Day
  • 15th December – Cat Herders Day
  • Cat Lover’s Month

Cat Tail Language – What Your Cat’s Tail Is Telling You

Cat tail language

Cat tail language

A cat’s tail can tell us a lot about how the cat is feeling and is a valuable communication tool not only between cats but also to communicate emotions to humans.

Paying attention to the cat’s tail is just one part of a larger picture. The position of the body, eyes and whiskers, as well as vocalisations (meowing, hissing, purring, chirping), are also important clues as to how the cat is feeling.

Read moreCat Tail Language – What Your Cat’s Tail Is Telling You