Semen collection in domestic animals

Transcription

1 Reproductive Biotechnologies Andrology I Semen collection in domestic animals Prof. Alberto Contri Aims Technological aim Diagnostic aim Methods for semen collection Indirect collection post-coital method (vaginal sponges, condoms) Paravaginal method (artificial vagina) Direct collection Massage of the deferent ducts Electroejaculation Cruent methods Orchiectomy Post-mortem epididymal collection Biopsy 1

2 For indirect collection we need to induce ejaculation Ejaculation has different phases 1) Erection 2) Emission 3) Ejaculation Erection Autonomic nervous system activity Modification of the blood bed in the erectile strucutres Emission Spermatozoa pass from deferent duct to the urethra Receive part of the accessory sexual gland secretion 2

3 Ejaculation Peristaltic contractio of the musculature of the urethra Expulsion of spermatozoa and seminal palsma out of the organism Paravaginal methods artificial vagina Mimic the natural mate Stimulate the male receptor in a manner similar to the female genital tract Different model of AV related to the species-specific characteristics Artificial vagina - scheme 3

4 Semen collection in the horse Artificial vagina Different models Colorado A.V. Semen collection in the horse Artificial vagina Missouri A.V. Semen collection in the horse Artificial vagina French AV (INRA) Japanese AV (Roanoke model) 4

5 Semen collection in the horse Artificial vagina Poland (short Krakaw) artificial vagina Semen collection in the bull Semen collection in the bull 5

6 Artificial vagina Electroejaculation Erection Parasympathetic stimulation - Increased pressure in the corpus spongiosum - Decresed peripheral resistances in the corpus cavernosum - Compression of the basis of the penis (ischiocavernosus muscle) - Compression of the bulbus glandis (bulbospongiosus muscle) Increase arterial influx Decrease venous efflux 6

7 Normal mate in the dog 7

8 Erection In the second part of the ejaculation We made a 180 -rotation on the planar plane to perform the turn Detumescence - Reduction of the blood imbalance increase in the arterial resistances (sympathetic stimulation) increase in the venous blood efflux - Contration of the smooth musculature of the walls of the cavernous tissue 8

9 o Familiar environment o Use the female in estrus ouseful to train the male oincrease the quality of the collection o In expert male, use swab from estrous secretion People 1. Assistent that manage the female 2. Assistant that manage the male (the owner) 3. Collector Male interact with the female In some case, the male mount on the back of the female Massage of the bulbus glandis to stimulate erection Move the skin of the prepuce over the bulbus Avoid the erection within the prepuce With the inch and the index finger compress the penis over the bulbus Start to collect the semen 9

10 Artificial vagina in the dog Improve the mechanical stimulation Safety of the collection Semen fractionation difficult Three different fractions Fraction 1: prostatic origin, volume 0.5 to 5 ml, clear, few spermatozoa Fraction 2: epididymal origin, volume 1 to 4 ml, white and dense, high concentraiton of sperm Fraction 3: prostatic origin, volume 1 to 80 ml, clear, without spermatozoa Ejaculation time Fraction 1 and 2 in 20 seconds Fraction 3 in more than 10 minutes 10

11 After collection remove the compression on the bulbus glandis After partial detumescence, remove the artificial vagina Urethral pulsatility could be maintained for minutes Try a second collection after at least 1 hour Reduced number of spemratozoa Increase in sperm quality (reduced senescence) Optimal schedule: collection 2-3 days apart Semen collection in the cat 11

12 Semen collection in the cat Artificial vagina Semen collection in the cat Electroejaculation Semen collection in the cat Electroejaculation 12

13 Semen collection in the cat Epididymal collection 13