Black Spots On My Jack Russell

7/18/2022 admin

Jack Russell terriers need a lot of mental stimulation to be happy. If they're not entertained, they'll act out by getting into things around the house. Make sure your dog has toys it likes. If your Jack Russell seems uninterested in its current toys, make a trip to a local pet shop to get it something different.

Jack Russell Black And White
Black Spots On My Jack Russell Crowe
Black Spots On My Jack Russells
Black Spots On My Jack Russell Terriers

Jack Russell Terrier Facts

The Jack Russell Terrier and the Russell Terrier are the same breed, but are entirely a separate breed from the Parson Russell Terrier. The Irish Kennel Club has recognized the Jack Russell Terrier in Ireland, adopting the FCI standard for the breed. At one time the AKC recognized the Jack Russell Terrier, however as of April 1, 2003 they.
Lens luxation is an inherited disease that can strike Jack Russell Terriers. It affects the eye, causing the lens to dislocate in one or both of the eyes. Sometimes, owners fail to notice the condition in the early stages, when the lens is only partially dislocated.

The majority of Jack Russell Terriers have these skin spots.

The spots will change in shade and size as your puppy matures.

Your puppy may or may not develop 'ticking.' Ticking refers to small spots -- usually just a few hairs -- of color in the white coat.

Jack russell terrier(WHAT YOU NEED TO KNOW)

Why is my dog getting black spots?

The black spots may darken naturally as they age.. Scabies are one of the common causes. Known as sarcoptic mange, this disease is caused by microscopic mites that burrow into the pooch's skin. Note that scabies is easily transferred between dogs, so keep your dog from the dogs that are infected with this disease.

Why is a Jack Russell called a Jack Russell?

The Jack Russell Terrier was developed in southern England during the mid-1800s by Parson John Russell, from whom the breed took its name. Russell aimed to create a working terrier who would hunt with hounds, bolting foxes from their dens so the hounds could chase them.

Why is my Jack Russell so hyper?

Solve Your Dog's Hyperactivity. Jack Russells are pretty hyper by nature, but many are excessively hyper because their owners don't help them release their energy. If your dog is excessively hyper it very likely needs more exercise. This is about the only way your Jack Russell will get tired before you do.

Why is my white dog getting black spots?

Black Spots and Your Dog's Pigment. The black spots that start manifesting on your pooch's body is usually a sign of hyper-pigmentation. This condition simply means that your dog is producing a higher amount of natural skin pigment, also known as melanin. This essentially is the condition that causes freckles in humans

Do Jack Russells get along with other Jack Russells?

Jack Russells will get along with most other dogs but should be watched around other terriers. As a class, terriers can be quite aggressive and territorial making it ill advised to have more than one terrier in a home.

How big will my Jack Russell get?

Jack Russells vary widely in size, because different types were used for different purposes and terrain. They range in height from 10 to 15 inches at the shoulder and weigh 13 to 17 pounds. Jack Russells who stand 10 to 12 inches and are longer than they are tall are known as Shorty Jacks.

Do Jack Russells get jealous?

Jack Russells are terriers, and they exhibit many classic terrier traits including excessive barking, willfulness, rudeness to strangers, dog aggression, possessiveness and jealousy. Proper training and socialization from an early age can ensure an even-tempered dog.

Why does my Jack Russell eat poop?

Stool Eating by Jack Russell Terriers. Terriers fed diets they can't properly digest will eat their stool because they consider it semidigested food rather than waste. There can be several causes of stool eating (also known as Copropagia) in dogs. Your terrier may eat the stool to avoid dealing with your response to it

Why do boxers get black spots?

Why do Jack Russells shiver?

Shaking. A lot of Jack owners report that their dogs shake, sometimes uncontrollably, and often in response to stimuli such thunderstorms or fireworks. This seems to be a product of the breed's intense nature. Shaking in dogs can be a sign of severe stress, pain, or anxiety.

Why do Jack Russells tremble?

Why do Jack Russells jump?

Short Dogs Can Jump. Did you know Jack Russell terriers can jump as high as five feet? These pups are also known for their endurance: they can run long distances and can even burrow underground and wait for days on end to chase out their prey (not an ideal situation due to dehydration).

Why do Jack Russells shake?

Why does my poop have black spots?

Black specks in adult stool often come from undigested food, but could also signal something more serious. Undigested foods, such as blueberries, will often cause black specks in stool. Intestinal bleeding or kidney problems are another possible reason for a black color.

Do Chihuahuas and Jack Russells get along?

Will 2 male Jack Russells get along?

are often aggressive with other dogs. Same-sex aggression and aggression towards other breeds of dogs is well documented with this terrier. It is strongly recommended that no more than two Jack Russells (of opposite sex only) ever be permitted to stay together unattended.

Jack Russell Black And White

What breeds get along with Jack Russells?

Lap dogs such as the Chihuahua, Yorkshire terrier, bichon frise or Shih Tzu are small, highly social dogs that are similar in size and intelligence to the Jack Russell terrier. When the Jack Russell and the lap dog grow up together, they can make excellent companions.

Should I get a Jack Russell terrier?

Jack Russell Terriers are hunting dogs by nature, so they enjoy running and chasing. As a result, this is a high energy dog and requires adequate exercise and stimulation. The high energy level of the Jack Russell Terrier is a good fit for athletic individuals who are looking for a dog that can keep up with them.

Why does my dog have black spots?

The black spots that start manifesting on your pooch's body is usually a sign of hyper-pigmentation. This condition simply means that your dog is producing a higher amount of natural skin pigment, also known as melanin. This essentially is the condition that causes freckles in humans.

Do Jack Russells and Beagles get along?

Docile Dogs. Jack Russells will get along with most other dogs but should be watched around other terriers. Jack Russells are best suited to pair with more laid-back breeds such as Labradors and golden retrievers. These dogs will not mind the smaller dog taking control of the house.

Do pugs and Jack Russells get along?

Both breeds are friendly, which is why, regardless of whether a Jug has more Jack Russell or Pug in him or her, they still make for a great companion dog. They are highly intelligent and therefore, easy to train if you are consistent. As Jack Russells and Pugs are both small dogs, Jugs tend to be small too.

Do Jack Russell terriers get cold?

As a general rule, dogs with a short coat (and no undercoat) will not cope well with frigid temperatures. A friend's Jack Russell Terrier starts to shiver when the temperature goes below 50 degrees F. That's not cold – it's just cool – but he's uncomfortably cold.

Do Jack Russell get along with cats?

First off, Jack Russells are high-energy creatures, and cats get stressed very easily. So in the best case scenario, an active Jack Russell will likely irritate your cat. It's not unheard of for Jack Russell terriers to harass smaller creatures such as cats, due to their strong hunting instincts.

What diseases do Jack Russells get?

Black Spots On My Jack Russell Crowe

Health. Common health issues affecting the Jack Russell breed include inherited eye diseases and deafness. Legg Perthes is a disease of the hip joints that can occur most commonly in smaller breed dogs, the Jack Rusell included. They are also prone to dislocation of the knee caps.

Why does my Jack Russell pee on my bed?

The most common reason why dogs experience peeing in their sleep is incontinence. This problem can come about from a number of different things, such as neuter/spay, urinary tract infection, and bladder stones.

Is Jack Russell a terrier?

The Jack Russell Terrier is a small terrier that has its origins in fox hunting in England. The Jack Russell is frequently confused with the Parson Russell terrier (see the American Kennel Club) and the Russell terrier, which is a shorter-legged, stockier variety.

Is Jack Russell terrier capitalized?

The rule for capitalization of dog breeds is that if the breed is named after a place name or a person, the breed is capitalized. Thus: Great Pyrenees, German Shepherd, Maltese, Labrador, Chihuahua, Jack Russell, Saint Bernard, Doberman.

How do I get my Jack Russell to stop barking?

Use the 'stop' command when your Jack Russell begins to bark at people, other dogs, the doorbell, squirrels and the like. Bring him inside if you are outside when he barks. Wait for 10 minutes, then let him out again. Repeat command and return inside if barking continues.

How do I get my Jack Russell to stop biting?

To stop play-biting, all you need to do is hold the puppy's mouth shut for a few seconds, say “No” firmly and then stick a chewy treat or toy in its mouth. This lets the dog know what it should be chewing on rather than human skin.

How big do Jack Russell Terriers get?

Should I get a Jack Russell?

But some Jack Russells are so brash and fearless they will take on a Rottweiler if it even looks cross-eyed at them. Two Jack Russell Terriers (regardless of sex or age) should never be left alone together. The Jack Russell Terrier is highly intelligent and can learn almost anything – very, very quickly.

What dogs get along with Jack Russells?

Why do Jack Russells bark so much?

Jack Russells often bark when frustrated, and they frustrate easily, so offer a helping hand when possible. Do not allow Jack Russells to run back and forth in the yard barking at other dogs in the distance. Discourage barking by calling him in the house when he runs and barks.

Why do they cut Jack Russell tails?

Dogs that are born with long tails sometimes undergo tail docking. This means that their tail is cut off, usually at a few days of age. The reason most people want their puppies' tails docked, is because they are used to seeing these dogs with short tails, for example, Boerboels, Dobermans and Jack Russell terriers.

Why are Jack Russell Terriers so hyper?

Jack Russells are pretty hyper by nature, but many are excessively hyper because their owners don't help them release their energy. If your dog is excessively hyper it very likely needs more exercise. This is about the only way your Jack Russell will get tired before you do.

Why are Jack Russells tails cut?

A pair of scissors is used to cut through the tail. The puppy squeals loudly and wriggles, but we are told that 'they do not really feel it'. I cannot understand why Jack Russell Terriers, Boxers, Doberman Pinschers and many other breeds are deemed to have tails which are in some way offensive to the eye.

Why do Jack Russells shake so much?

Shaking. A lot of Jack owners report that their dogs shake, sometimes uncontrollably, and often in response to stimuli such thunderstorms or fireworks. This seems to be a product of the breed's intense nature. That said, while it might be a common trait of the breed, it's always a good idea to talk to your vet about it

Why do Jack Russells stare at you?

Let's face it: Dogs love their owners, but when they stare expectantly, it's not usually because they're trapped in a reverie of devotion. Rather, it's because they're thinking they might get something. Before you try it, be aware that staring directly into a dog's eyes can be considered a direct challenge.

Why is my dog getting bald spots?

Bald Spots in Dogs: Common Causes and Treatments. Allergies are a frequent trigger for hair loss in dogs. Like people, dogs can have an allergic reaction to foods, environmental triggers such as pollen, or to parasites like fleas or mites. Flea bites are behind most dog allergies, however.

Why does my Jack Russell growl at me?

It's very common for dog owners to punish their dogs for growling. Unfortunately, this often suppresses the growl—eliminating his ability to warn us that he's about to snap, literally and figuratively. On other occasions, punishing a growling, uncomfortable dog can induce him to escalate into full-on aggression.

Why does my Jack Russell shake so much?

Why do Jack Russells live so long?

They are also prone to dislocation of the knee caps. Jack Russells are well known for living long and healthy lives, as breeders have protected the gene pool, preventing direct in-line breeding. Given proper care, life expectancy averages about 15 years, possibly even longer.

What age is a Jack Russell fully grown?

Medium-large dog breeds (Collies, Labrador Retrievers, Boxers) are at full growth by about 18 months and at their full weight by about 2 years of age. Giant dog breeds (Great Danes, Mastiffs) may take up to three years to reach their full weight, though they should be fully grown into their paws by about 18 months.

Why do Jack Russell Terriers shake?

Why do Jack Russells bark a lot?

Keep Your Jack Russell Terrier from Barking. Barking is a completely natural habit for a dog, and Jack Russells tend to be a bit noisier than most breeds. The biggest reason that Jack Russells bark are because of boredom or anxiety.

Why are Jack Russell Terriers so aggressive?

Most behavioral problems are due to a lack of companionship, discipline, activity and exercise. For a Jack Russell that is very aggressive with other dogs, a technique is to squirt the terrier in the face with water whenever he growled at other dogs. You must stop this behavior before it becomes dangerous.

How much should my Jack Russell eat?

Thusly Jack Russell Terriers on average daily need around 800-900 calories (distributed in 4-6 meals) as puppies while 13-17 pound adults need 2-3 meals with a combined intake of approximately 450-650 calories per day (depending on how active they were).

Should my Jack Russell wear a coat?

In contrast, dogs with thick coats may not need a coat and may actually overheat if they are encouraged to wear one. This is because their coat is designed to keep them warm – even in bitter conditions – and they therefore do not require any additional protection against the elements.

Sind Jack Russel schlau?

Sein Wesen weist allerdings darauf hin, dass er früher zur Jagd als Arbeitsterrier eingesetzt wurde: Der Jack Russel Terrier ist ein sehr lebhafter und aktiver Hund. Darüber hinaus ist er äußerst wachsam und schlau.

Are Jack Russells intelligent?

Personality: Loves To Work (And Lives To Play) Jack Russell Terriers are hunting dogs by nature, so they enjoy running and chasing. This smart little dog is not afraid to nip or bite back when it feels it is threatened. Otherwise, they're a happy breed and thrive when respected.

Are Jack Russells friendly?

The Jack Russell terrier is a happy, energetic dog with a strong desire to work. However, these dogs are alert and make good watchdogs. The breed is naturally assertive and may not tolerate young children or other animals in the home. They can be aggressive toward other dogs.

Are Jack Russells aggressive?

My Jack Russell is out of control! He is aggressive towards other dogs and people. Same-sex aggression and aggression towards other breeds of dogs is well documented with this breed. It is strongly recommended that no more than two Jack Russells (of opposite sex only) ever be permitted to stay together unattended.

Are Jack Russells dangerous?

Most behavioral problems are due to a lack of companionship, discipline, activity and exercise. A Jack Russell Terrier that bites can be a big problem. You must stop this behavior before it becomes dangerous.

Are Jack Russells smart?

Why is my dog getting more spots?

Age spots in your dog are caused by a buildup of excess melanin in the skin. If age spots appear, your vet may want to closely examine the pigmented areas for any changes in skin tone or texture. These types of changes may indicate additional damage from the sun such as skin cancer or more serious conditions.

Are Jack Russells trainable?

Jack Russells are highly trainable dogs and soak up new tasks like a sponge. They are terriers and can exhibit stubbornness if they don't like the attitude of the person training them. Positive reinforcement and mixing up the daily training routine will keep your Jack Russell engaged and interested.

Are Jack Russells loyal?

Jack Russell Terriers are intelligent, loyal, affectionate and are never shy. However, they were bred to be hunting dogs and therefore have a lot of energy and a strong hunting instinct.

Are Jack Russells hypoallergenic?

Puli, Komondor, poodles), and wirehaired dogs (Wirehaired Fox Terrier, Broken Coat Parson/Jack Russell Terrier, Wirehaired Dachshund, Rough Coat Brussels Griffon, etc.). These breeds tend to have less fur than other breeds, but more importantly, generally shed less dander. Keep your dog out of the bedroom at all times.

Sind Jack Russel Jagdhunde?

Als Stammmutter aller Jack Russel Terrier gilt seine Hündin Trump. Heute gibt es den Jack Russel Terrier nahezu überall. In Europa hält man sie inzwischen kaum noch als Jagdhunde, sondern überwiegend als Begleithunde. Im Jahr 2000 erkannte der FCI den Jack Russel Terrier als eigenständige Hunderasse an.

Are Jack Russells vicious?

The small terriers are known for being particularly vicious. Jack Russell terriers have topped the list of dogs most likely to attack humans. The terriers were found to be more aggressive than other breeds of dogs that are perceived to be aggressive, like pit bulls or bull terriers.

Do Jack Russells shed?

The Reality - Jack Russell Terriers do shed. Typically, the shorter the hair in this breed, the more it will shed, however there are absolutely no guarantees. The shedding may get worse when the seasons change. Also, people who like to bathe their dogs a lot end up with even more shedding and dry skin.

Are Jack Russells fast?

Jack Russell Terrier — Small, Speedy and Stubborn. Don't let his small size fool you — the Jack Russell Terrier can reach speeds up to 25 mph in short bursts.

How much is a Jack Russell puppy?

Puppies can be available for as low as $800 but can also cost $2500. On average. a well-bred, ethically raised Jack Russell Terrier puppy will cost you $1500. Though puppies can be purchased for a lower price, hopeful puppy buyers should be very wary.

Is Jesse the Jack Russell still alive?

Meet Jesse, an 11-year-old Jack Russell Terrier, the viral YouTube star that can perform 400 tricks and counting. “I fell in love with the Jack Russell Terrier breed after living in England and taking care of a little dog named Frasier; who of course was a Jack Russell Terrier,” she explains.

Is Jack Russell a good family dog?

Because he is a baying terrier, the Jack Russell can be vocal. However, these dogs are alert and make good watchdogs. The breed is naturally assertive and may not tolerate young children or other animals in the home. They especially can be aggressive toward other dogs.

How long is a Jack Russell pregnancy?

Dogs are pregnant for about 63 days or nine weeks, though this may vary by a few days depending on several factors. A veterinarian will be able to run tests to more accurately determine how far along the pregnancy is and when a dog will give birth.

How much is a Jack Russell terrier?

As with most breeds, there is a large amount of disparity in price for a Jack Russell Terrier. Puppies can be available for as low as $800 but can also cost $2500. On average. a well-bred, ethically raised Jack Russell Terrier puppy will cost you $1500.

Is a Jack Russell A smart dog?

American Pit Bull Terrier — You may be thinking, “wrong list,” but this is one of the smartest dog breeds around. This dog has the desire to please (and then some), and it's probably the most tenacious breed of all. Parson Russell Terrier — Some of you may remember this dog breed as the Jack Russell Terrier.

How much should my Jack Russell weigh?

At what age is a Jack Russell fully grown?

When Do Dogs Stop Growing? Most canines reach their full size by the time they are 12 to 18 months old although it does take longer for some of the largest breeds to finish growing. Some breeds even reach a full frame within the first six months of life although it takes longer for the rest of the body to catch up.

Will my Jack Russell ever calm down?

As much as your Jack Russell will love to show off that he set another dog running with his or her fierce bark, you must correct this behavior. It will help when he or she comes across a dog who is not so well trained. It is essential that you socialize your Jack Russell during their training. 6.

Can I give my Jack Russell milk?

Dogs don't always agree with milk. You can tell if your Jack Russell is lactose intolerant if it gets diarrhoea after ingesting milk, cheese, or any other dairy product. When a dog is born, its lactase production is at a lifetime high because of its need to drink its mother's breast milk.

What Should I Feed My Jack Russell?

The primary ingredients in your Jack Russell Terrier's high-quality dry commercial diet should be meat-based proteins, such as poultry, beef or fish. Dog food ingredients are listed in descending order of their percentage in the food, so the first named ingredients are the main ones.

Is a Jack Russell a cross breed?

Also known as a Jackadoodle, the Jack-A-Poo is a cross breed of the Jack Russell and a poodle. Like the Jack Russell, they are a fantastic family companion, with a loyal and loving nature. However, they can be a very loud addition to the family home if they're adopted or purchased at a young age.

Why does my dog have black spots on his balls?

These minor skin conditions are caused by mild infection or clogged pores. They are extremely common and may appear as dark spots on the scrotum.

Why does my dog have black spots on his belly?

It's nice to sit with your dog, and give him a rub on the belly, but when you see blotches and spots on his tummy skin, it can give you a fright. Some dogs develop dark patches on their skin as they get older. They aren't itchy or scaly, the skin isn't thickened and they don't cause the dog any harm at all.

Why does my dog have black spots on her belly?

The black spots may darken naturally as they age.. Scabies are one of the common causes. Known as sarcoptic mange, this disease is caused by microscopic mites that burrow into the pooch's skin. Scabies usually appears on the ear flaps, elbows, hocks, abdomen and chest of infested canines.

Is there a difference between a Jack Russell and a Jack Russell terrier?

However, it's the Parson terrier that was bred as a hunting dog with a higher energy level. There are not a lot of differences between the Parson, Jack Russell, and Russell terrier, but all three are considered different breeds, and this is where it can get confusing.

What is the best dog food for my Jack Russell?

The Best Dog Food for Jack Russells: The Best Dog Food for Jack Russells: Blue Buffalo Life Protection Formula. Taste of the Wild Grain Free Dry Dog Food. Wellness Core Grain Free Dry Dog Food. Orijen Puppy Biologically Appropriate Dry Dog Food. Purina Beyond Grain Free Wet Dog Food.

Are Jack Russells cuddly?

“They look like little cute cuddly things, and they are, but they can really be pretty feisty.” In the United States, working versions of the breed are referred to as Jack Russell terriers, which includes a range of body types.

Are Jack Russells affectionate?

Jack Russell Terriers are very loyal and affectionate. They want to be with people all the time. They are also keenly alert and will alert you to every new person, animal or thing encroaching on their property. Socialization is very important both with people and other animals, especially other dogs.

Are Jack Russells purebred?

Jack Russell Terriers are a type, or strain, of working terrier; they are not pure bred in the sense that they have a broad genetic make-up, a broad standard, and do not breed true to type.

Are Jack Russells yappy?

Why does my dog have black spots on his skin?

Black Spots On My Jack Russells

Dogs with severe skin allergies can develop black patches but the skin in that area is thick, itchy, and almost like elephant skin. That is called lichenification and it is caused by inflammation. If these dark skin patches seem dry or troublesome to your pet, it may be a good idea to have your vet take a look.

Why does my dog have black spots on tongue?

We do know that the Chow is not the only breed with a blue-black tongue. The Chinese Shar-Pei shares this trait as well. Spots on tongues are simply deposits of extra pigment, like birthmarks and freckles on people. Dogs often have spots of dark pigment on their skin, too, hiding under their coats.

Why does my dog have black spots on his gums?

Some dogs, especially those of certain breeds, such as the chow chow, have black coloring in their mouths. Your dog may have flat, black splotches on his gums, inner lips or on his tongue. This is normal pigmentation for some dogs. As your dog ages, these patches may change slightly in size or shape.

Why does my dog have black spots on her teeth?

Plaque along the gum line is easily the most common cause of gingivitis. What looks like a black spot along the gum line of a tooth is much more likely to be exposed furcation than a “cavity.” Dogs get caries, or “cavities,” much less commonly than do humans.

Why does my dog have black spots on him?

Dogs with severe skin allergies can develop black patches but the skin in that area is thick, itchy, and almost like elephant skin. That is called lichenification and it is caused by inflammation. Fleas typically do not cause dark patches but will cause hair loss along the back of the hind legs.

What is a pug Jack Russell mix?

The Jug is not a purebred dog. It is a cross between the Jack Russell Terrier and the Pug.The best way to determine the temperament of a mixed breed is to look up all breeds in the cross and know you can get any combination of any of thecharacteristics found in either breed.

Is a Jack Russell a dangerous dog?

Merseyside Police found more reports of canine attacks on humans involving Jack Russells than any other breed in 2015. The terriers were found to be more aggressive than other breeds of dogs that are perceived to be aggressive, like pit bulls or bull terriers.

Is a Jack Russell a lap dog?

Lap dogs such as the Chihuahua, Yorkshire terrier, bichon frise or Shih Tzu are small, highly social dogs that are similar in size and intelligence to the Jack Russell terrier. However, Jack Russell terriers and lap dogs tend to be very demanding of attention, and jealousy can occur.

Is milk bad for Jack Russells?

You can tell if your Jack Russell is lactose intolerant if it gets diarrhoea after ingesting milk, cheese, or any other dairy product. Milk is an excellent source of high-quality protein and calcium, but these can be found elsewhere in other foods that it's less common for your dog's digestive system to disagree with.

Is a Jack Russell a pedigree?

Black Spots On My Jack Russell Terriers

Meet Britain's Surprising New Pedigree Dog Breed – The Jack Russell Terrier. The number of pedigree dog breeds officially recognised in the UK is set to go up to 216, as the Kennel Club, the UK's largest organisation dedicated to the health and welfare of dogs, recognises the Jack Russell Terrier as a pedigree breed.

Do Jack Russells get along with other dogs?

Jack Russell terriers may be aggressive toward other dogs if they are not socialized at an early age. Well-trained and socialized Jacks make wonderful, lively family dogs and can coexist peacefully with other dogs. However, some dogs will be able to adapt better than others to life with a typical Jack Russell terrier.

What dogs do Jack Russells get along with?

How big do Jack Russell terrier chihuahua mix get?

Like any mixed breed, the appearance of Jack Russell and Chihuahua mix puppies can vary greatly depending on the characteristics they inherit from the parents. The average size of both male and female Jack Chis is 10 to 15 inches and weight is 8 to 18 pounds.

Why does my dog have black spots on his teeth?

Why does my dog have black spots on her tongue?

Why does my dog have black spots on her gums?

Healthy gums should be bubble gum-pink in color. Some dogs, especially those of certain breeds, such as the chow chow, have black coloring in their mouths. Your dog may have flat, black splotches on his gums, inner lips or on his tongue. This is normal pigmentation for some dogs.

Why did my dog's hot spot turned black?

That is called lichenification and it is caused by inflammation. Fleas typically do not cause dark patches but will cause hair loss along the back of the hind legs. Your dog would also be itchy if there were fleas. Make sure to get a good monthly flea preventative from your veterinarian.