Tom
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Normal Breeding

• Puberty in the male (tom) is reached at approximately nine months or 3.5 kg.
• Penile spines
  • Present with testosterone
  • Absent without.

This photo shows what a tom's penis looks like with spines (left) vs. without (right).

• Breeding is most likely to occur in the male's home breeding territory during the nocturnal period.
• The copulatory act of the male and queen have been described in detail. 
  • Mounting the queen and firmly grasping the neck with his teeth, the male positions himself for insertion of the penis into the vagina. 
  • After successful breeding, the queen emits a scream and strikes at the male while he rapidly retreats.
• During the queen's period of sexual receptivity, the tom may breed the queen eight times in 20 minutes and then repeatedly during a day. 
  • In natural breeding situations, a tom may breed until he is either 'satisfied' or physically exhausted. 
  • Multiple matings over a 24 hour period probably enhance the chance that the queen will ovulate.
• Despite the fact that repeated matings occur over a short time period, only one report shows the effect of multiple semen collections on tomcat semen characteristics. 
  • Most published data available on tomcat semen characteristics reports only single collections taken daily, every other day, or weekly. 
  • In the report that collected multiple ejaculates, electroejaculation was used on anesthetized toms to collect four consecutive semen samples at weekly intervals. 
  • There were more sperm cells in the second ejaculate than in the first, third or fourth ejaculates. 
  • Electroejaculation, however, has been shown to produce larger volumes of semen with fewer total cells than collections using an artificial vagina. 
  • Using current information, it is therefore commonly advised to breed a tom in one of two ways: 
    • 3 times a week (every other day) or 
    • once daily for a short time. 
  • Multiple breeding each day for 1 to 3 days, however, are preferred for maximum fertility. 
  • Despite the preference for multiple matings, no convincing research exists which suggests the effect of continual repeated mating on tomcat semen characteristics.
  • Current information does not reveal whether the multiple matings by the tom are primarily for deposition of more semen, to enhance successful induction of ovulation or a combination of both.

• Collecting an ejaculate from the tom can be performed using an artificial vagina or an electroejaculator.
• An artificial vagina has been described by Sojka and consists of a test tube on a rubber pipette bulb inserted into the mouth of a small plastic bottle. 

  

  • A daily training period of 2-3 weeks is needed before the tom will become accustomed to an artificial vagina. 
  • Since 30-40% of toms cannot be trained to use an artificial vagina, it is not a procedure commonly performed in practice.
• A normal ejaculate should contain 21.5 - 117.0 X 10⁶ cells in 0.03 -0.09 ml. 
• Motility should be approximately 40 - 80% and 
• 50 - 70% of the cells should be morphologically normal.
• An electroejaculator can be used on the anesthetized tom to collect an ejaculate. 
  • A special probe and instrumentation are needed to electroejaculate the tom. 
  • Technique
    • •Medetomadine –130-140 ug/kg IM
    • 3 Fr catheter inserted 9 cm
    • Urethral sperm
      • Lower volume
      • Same characteristics as EE  
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  • A semen sample collected by electroejaculation should have a volume of 0.11 - 0.49 ml and contain 11.1 - 65.9 X 10⁶ cells. 
  • Motility should be approximately 50 - 70% and 
  • 40 - 80% of the cells should be morphologically normal.
• A more practical method to prove the existence of spermatogenesis is the recovery of sperm cells from the vagina immediately after natural mating. 
  • Sperm cells can be collected from the vagina using a cotton swab or flushed out using a pipette and observed under a microscope. 
• An alternative method to document sperm production is by recovering sperm cells from the bladder of the tom after mating. 
  • Retrograde flow of the tom's ejaculate into the bladder normally occurs when ejaculates are induced by natural mating, an artificial vagina or an electroejaculator. 
    • In one report, 9 - 45 X 10⁶ sperm cells were recovered from the bladder after the tom ejaculated into an artificial vagina. 
    • Retrograde flow into the bladder was calculated to be 14 - 90% of the total ejaculate. 
    • Clinically, the urine in the bladder collected by cystocentesis immediately after natural mating can be conservatively assumed to contain about 20% of the total number of the cells in the ejaculate. 
    • Counting the total number of cells in the bladder post coitus and multiplying by five can be used to give an estimate of the total number of cells in the ejaculate.

• Artificial insemination can be performed in the queen using semen collected with an electroejaculator or an artificial vagina. 
• A tomcat catheter can be used to inseminate the ejaculate into the queen. 
• Following AI, the queen needs the appropriate stimulus to induce ovulation. 
• Results of artificial insemination using fresh semen have yielded pregnancy rates of 75% and 10% using frozen semen.
• With a tom that has very poor semen or with a chronically infertile queen, surgical insemination via a laparotomy and deposition of the semen directly into the uterine lumen using a needle may improve chances of conception.

• Infertility in the tom can be broken down into three categories: 
  • 1) the failure to show sexual interest 
  • 2) the failure to breed successfully and 
  • 3) the failure to impregnate queens after successful breeding.
• Failure to show sexual interest can arise when the tom is placed in strange surroundings to breed. 
  • Instead of being able to focus on breeding, he spends his time establishing a new territory in these unfamiliar surroundings. 
  • To avoid this problem queens should be placed in the tom's territory for breeding.
• Because cats are nocturnal breeders, it is also best to allow the tom and queen to breed at night.
• The tom may be a novice breeder and may need the assistance of an experienced queen to minimize the anxiety of the first breeding.
• Some toms have poor libidos and are not interested in breeding. 
  • This condition may be a primary problem of the tom or result from a queen's dominance over the tom in the social order. 
  • No hormonal therapy is recommended for toms that fail to show sexual interest. 
  • If testosterone concentrations are normal in the tom (1000 pg/ml) testosterone therapy will not enhance libido but will probably decrease sperm production. 
  • Artificial insemination may be considered when the tom refuses to breed or the queen refuses to accept the tom.
• When a tom shows good libido but fails to breed successfully, dental and penile problems should be considered. Because the neck bite at breeding is essential to successful breeding, toms with dental problems will sometimes not be able to breed effectively.
• Hair rings around the penis can also cause discomfort which will impede successful copulation. 
• Size differential between tom and queen can also prevent successful mating. 
• The failure to impregnate queens after successful matings which induce ovulation should alert the clinician to the possibility of congenital or acquired azoospermia which can be detected by performing a breeding soundness examination.
• Cryptorchid toms should not be used for breeding because of the hereditary potential of the problem.