Genetic defects can occur in any breed and can affect any system in the body. Some genetic diseases may occur in many breeds; others occur in only one or a few breeds.
The following is a brief explanation of how genetic defects may be inherited and expressed. Diseases that follow a dominant pattern of inheritance need only one abnormal gene.
That is, if only one parent is affected, the condition will show up in each successive generation. Some individuals may be only mildly affected with the condition, making it difficult to detect. In such cases, the condition can mistakenly be thought to skip generations.
Diseases that follow a recessive pattern of inheritance occur in homozygous individuals, meaning dogs with two abnormal genes. Dogs with one mutant and one normal gene are heterozygous, and they are carriers of the condition. They appear normal but can pass the abnormal gene to their offspring. Recessive mutant genes can be passed through many generations before emerging in the offspring of two dogs that carry the same genetic mutation.
Polygenic disorders result from the cumulative action of a number of different genes. The exact number of genes involved and their individual functions are difficult to determine, and the pattern of inheritance tends to vary from family to family. Polygenic inheritance can sometimes mimic either dominant or recessive inheritance, and this feature may lead to erroneous conclusions regarding the type of underlying genetic abnormality. Chromosomal anomalies — defects in chromosome number and structure — can also cause genetic diseases.
Dogs normally have 39 pairs of chromosomes on which genes are located. Major abnormalities in chromosome number and structure can produce serious defects. You have performed all necessary health checks, genetic screenings, and selected the perfect mate for your bitch.
It is an excellent idea to work out a contract with the owner of the stud dog before breeding takes place. The agreement concerning stud fees should be in writing and clearly state all obligations and circumstances. The contract should be signed by all parties to the transaction, and each signer should receive a copy. The mode of payment may differ. The contract may state that the owner of the sire is not obligated to sign an AKC litter registration application until the stud fee has been paid.
Keep in mind that the AKC cannot settle disputes between individuals in regards to contracts and breeding arrangements. Good puppies start long before breeding ever takes place. Both parents need long-term care — what dog people call conditioning — to produce the best offspring.
This means regular veterinary care, screening for genetic problems, pre-breeding tests, and regular exercise and good nutrition. Bitches should not be overweight and should have good muscle tone before breeding. Additionally, a bitch that is in good mental condition will make a better mother than a bitch that is insecure, snappy, or has an otherwise unstable temperament. One month before breeding, the bitch should have a thorough pre-breeding physical examination by a veterinarian.
Her vaccinations should be current, and she should be tested and treated for parasites. You may also want to have the bitch and male tested for brucellosis, an infectious bacterial disease that can cause sterility or spontaneous abortion in affected dogs.
The age at which dogs reach sexual maturity depends to a large extent on their breed. Small breeds tend to mature faster than large breeds. On average, however, males become fertile after six months of age and reach full sexual maturity by 12 to 15 months. Healthy stud dogs may remain sexually active and fertile to old age. Adult males are able to mate at any time. Bitches have their first estrus also know as season or heat after six months of age, although it can occur as late as 18 months to two years of age.
Estrus recurs at intervals of approximately six months until late in life. During estrus, the female is fertile and will accept a male. The bitch should not be bred during her first season. Keep in mind that AKC Rules do not allow, except with special documentation, the registration of a litter out of a dam less than 8 months or more than 12 years of age at the time of mating, or by a sire less than 7 months or more than 12 years of age at the time of mating. Responsible breeders generally do not breed a bitch at the first heat to avoid imposing the stress of pregnancy and lactation on a young, growing animal.
It is also customary to avoid breeding a bitch on consecutive heats to allow sufficient time for recuperation between pregnancies. Most dogs are first bred between the 10th and 14th day after the onset of proestrus.
As long as the bitch will accept the male, mating every other day for a total of two or three matings is generally considered sufficient. However, signs of proestrus are not obvious in some bitches. To catch the peak fertile period, a veterinarian may need to perform hormone tests or examine vaginal smears under a microscope. Bitches are usually less inhibited by new environments so they are usually taken to the stud.
Breedings involving young males proceed more smoothly if they are paired with experienced bitches. Sometimes human handlers must step in with assistance or guidance during breedings. Some breeds are more apt to need assistance than others because of anatomical considerations. Discussing this process with your own breeder will help you be prepared. During breeding, the male mounts the female from the rear and clasps her midsection with his front legs. Rapid pelvic thrusts follow until penetration and ejaculation take place.
After the pelvic thrusts cease, the dog and bitch will not separate for 10 to 30 minutes. Known as a tie, this results from a swollen section of the penis called the bulbus glandis. During the tie, the male may move around until he and the bitch are positioned rear to rear. Do not try to separate the dogs during the tie because it can injure either or both animals. After some time, they will part naturally.
Artificial insemination is a relatively simple procedure that can be used when natural breeding is impractical. The AKC accepts registration of a litter mated by artificial insemination using fresh semen, fresh extended semen, and frozen semen, provided the proper procedures are followed. Registration of these litters requires DNA certification.
Canine gestation lasts approximately 63 days. Signs of pregnancy include an increase in appetite, weight, and nipple size. However, a bitch with false pregnancy may also show these signs. A veterinarian can usually confirm a pregnancy through abdominal palpitation at 28 days or by using ultrasound or X-rays. Once pregnancy is confirmed, you should talk to your vet about special feeding requirements and about what to expect during pregnancy, labor, and after birth.
You should also be briefed on how to recognize and respond to an emergency. A bitch in good condition should continue into pregnancy with the same caloric intake that she had during adult maintenance. Her food intake should be increased only as her body weight increases, beginning about the last five weeks before whelping. Daily food intake should be increased gradually, so that at the time of whelping she may be eating 35 to 50 percent more than usual.
As her weight and food intake increase, begin offering small, frequent meals to spare her the discomfort that larger meals can cause, especially in a small dog. If you have been feeding your bitch a well-balanced, high-quality diet, you should not need to add anything to her food during her pregnancy.
However, some breeders advocate supplementation with a protein source such as evaporated milk, eggs, meat, or liver. It is a good idea to build a whelping box well in advance so the bitch has time to become accustomed to it. Unless you have already accustomed her to a whelping box, she may choose your closet or another inappropriate place for a delivery room.
An ideal whelping environment is warm, dry, quiet, draft-free, and away from all other dogs when possible. Confinement and whelping location of your bitch is relative to her breed and size.
A good whelping box is roomy and has low sides so you can easily reach in. It should also have a small shelf or roll bars running halfway up along the sides so the pups have something to crawl under to avoid getting rolled on by the bitch. Many breeders prefer to line the box with newspapers until after delivery because paper can be changed quickly when it becomes soiled. After whelping, newspapers are typically replaced with non-skid bath mats, outdoor carpeting, or something else that provides better footing for the puppies.
Approximately 24 hours after her temperature drops, she can be expected to enter the first stage of labor when the cervix dilates and opens the birth canal for the passage of puppies. At this time, she will pant, strain, and appear restless. This stage of labor is followed by actual abdominal straining and production of the puppies and placentas. Most bitches give birth easily without the need of human help. Each puppy emerges in its own placental membrane, or sac, which must be removed before the puppy can breathe.
The mother usually takes care of this by tearing off and sometimes eating the membrane and then severs the umbilical cord.
After delivery, she will lick each puppy to stimulate its breathing. You should keep track of how many placentas are delivered and ensure that the number matches the number of puppies because a retained placenta may cause problems. You must take over if the bitch neglects to remove a sac or sever an umbilical cord. A puppy can remain inside the sac for only a few minutes before the oxygen supply is depleted. The cut end should be painted with iodine to prevent infection.
At the time of birth, the bitch will be busy cleaning her puppies, warming them, and allowing them to suckle. Although bitches vary in the frequency of their heat cycles, an average female goes through heat about every seven months. A bitch is not considered abnormal unless she has not had an obvious heat cycle for one year.
That depends on how many puppies she whelped the first season and how well she maintained her body condition during pregnancy , whelping, and lactation. If she had several puppies and was thin by the time they were weaned, she probably cannot regain normal body condition before she is in heat again and thus should not be bred. If she had few puppies at the first breeding and is in excellent body condition, she potentially could be bred again.
Every circumstance and every bitch should be evaluated individually. Particularly later in the pregnancy when her uterus takes up much of the space of the abdomen, she may have trouble eating a significant amount of food. At whelping, a bitch should weigh 5-to percent more than before breeding. Try to avoid obesity as it is associated with difficulty whelping, increased birth defects in neonates, and stillbirths. Likewise, a thin body condition can cause conception failure, loss of pregnancy, and low-weight pups.
Puppies can absorb these antibodies from their intestinal tract for only about the first 24 hours of life. This is common behavior that generally causes no risk to puppies.
Hand mating as used in most breeding farms can potentially increase this number to or more. Horses are not monogamous animals, and pairs of horses do not establish lifelong relationships. Instead, horses do form long-term relationships within groups, called herds. Offspring of the herd members are usually driven out between the ages of 2 and 5 years. The remarkable and rapid rise of Into Mischief continues unabated.
Buying any horse is a poor investment. It will not increase in value and will cost you, over time, much more than its initial purchase price. You buy a horse for love, not for monetary gain. Yes, lions can mate with their siblings either knowingly or unknowingly. You will see the same dominating male lion mating with most of the lioness in the same group or with a different group.
The females will expel their male cubs from the pride when the cubs become sexually mature at the age of about three years. Super Moderator. Yes, worst genes are often the winner in breeding close relatives. They often end up more pronounced depending on how passed as well. And yes, a son will breed his own mother. Horses have a smell-memory of around 10 years so yes they normally do recognise their offspring even if they have been away for a while.
Originally Answered: Can you breed a year-old mare? How old is too old? A: As a general guideline, broodmares are past their reproductive prime as they approach about 15 or 16 years old.
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