Mating - Answers

Arlo Guthrie — Tue, 21 Apr 2009 11:59:02 GMT

Current Revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 4/21/2009 11:59:02 AM

ANSWERS

At what age do dogs and bitches reach puberty?
6-12 months of age in dogs, and 12-14 months in bitches (although this can be any time from 6 months). Generally, large breeds tend to reach puberty later.
At what age does the fertility of the decline?
7 years of age.
What is spermatogenesis?
The production of spermatozoa. This commences at approximately 5 months of age in both dogs and toms.
What is the function of the cells of Leydig?
Testosterone production.
From which endocrine gland is lutenising hormone produced, and what is its function?
The anterior pituitary. It stimulates the production of testosterone.
What is meant by a "gonadotrophin"?
Any hormone having a stimulating effect on the gonads.
What is the function of follicle stimulating hormone (FSH) in the male?
This increases spermatogenesis via the Sertoli cells.
What is the function of the Sertoli cells?
Production of oestrogen and nutritive fluid for the sperm.
What is the function of gonadotrophin releasing hormone?
Mediation of the negative feedback of testosterone upon the release of follicle stimulating hormone and lutenising hormone.
What is meant by "hypogonadism"?
A rare condition where poor development of the gonadal tissue results from a primary abnormality in the secretion of pituitary hormones.
What is meant by "anorchia"?
Complete absence of testes.
What is the difference between cryptorchidism and monorchidism?
Cryptorchidism means that one or both of the testes are retained within the abdomen, whilst monorchidism means that an animal possesses only one testicle.
What term describes inflammation of the testes?
Orchitis.
What is the term that describes failure to retract the penis into the prepuce?
Paraphimosis.
What is meant by "priapism"?
Persistent enlargement of the penis in the absence of sexual excitement.
What is meant by "phimosis"?
Inability to extrude the penis due to an abnormally small preputial orifice.
What is the "first fraction", and what is its function?
A small volume of clear fluid from the prostate of the male ejaculated prior to mounting. Its function is to clear the urethra of cellular debris and urine.
Describe intromission.
The dog achieves a full erection, enters the bitch and ejaculates the second fraction.
What is the purpose of "the tie" and how long does this last?
The tie enables the third fraction of ejaculate to flush sperm through the cervix and into the uterus. It lasts from 10-60 minutes, the average being 20 minutes.
Which accessory glands are present in the tom but not in the dog?
The bulbourethral glands, which contribute to seminal fluid production.
What fraction of ejaculate is used in the assessment of fertility?
The second fraction.
What stains are suitable for the microscopic examination of spermatozoa?
Eosin and Nigrosin. In dead sperm, the acrosome (head) is detached and stained pink. In live sperm, the acrosome is attached and remains unstained.
By which method of cell division do spermatozoa multiply?
Meiosis.
Where are the sperms stored?
The epididymis.
Give 2 other terms for the deferent duct.
- Vas deferens.
- Ductus deferens.
  The deferent ducts connect the epididymis to the urethra.
Why are multiple matings more likely to result in ovulation?
More lutenising hormone is released.
What 2 natural factors increase the likelihood of conception?
- The relatively long period of fertility of the ova.
- Spermatozoa can survive for long periods within the female reproductive tract.
In addition to clinical assessment, name 2 further methods of determination of the optimum time for mating.
- Measurement of vaginal plasma concentration (Pre-mate Test).
- Vaginal cytology.
Why might the apparent length of pregnancy, assessed from the time of mating vary from between 56 and 72 days?
An early mating produces an apparently longer pregnancy, since spermatozoa survive within the female tract until ovulation or egg maturation. A late mating produces an apparently shorter pregnancy, since the eggs are waiting to be fertilised some time after ovulation.
Upon what days of heat is it recommended that a bitch is mated?
Day 11 & day 13.
What is meant by "misalliance"?
An unwanted pregnancy.
If a client wishes to breed from more than 2 bitches, a licence is required. Which legislation governs this?
The Breeding of Dogs Act 1973.
List 6 factors that ought to be taken into account by an owner prior to breeding.
- Temperament.
- Conformation.
- Space.
- Time.
- Money.
- Market.
A client wishes to use his 3 year old Staffordshire bull terrier as a stud dog; what advice would you give him?
- Bring the dog to the surgery for a thorough health check, in particular to assess the animal for congenital or hereditary defects such as cataracts, cryptorchidism and over-shot or under-shot jaws.
- Ensure that the dog is wormed and vaccinated prior to mating.
- Suggest that the owner purchase a book on dog breeding if he is inexperienced.
- Recommend that he contact the Kennel Club to locate a suitable bitch - she should be of good conformation, temperament and experienced.
- Never interfere with "the tie".
- Suggest that he contact the surgery in the event of any further queries.