Factors affecting on semen quality...
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ReferencesBarth A.D and Waldner C.L. 2002. Factors affecting breeding soundness classification of beef bulls examined at the Western College of Veterinary Medicine. Can Vet J 43(3):274-284Hafez.E.S.E and Hafez.B. 2000. Reproduction in farm animals 7 th edition. Lippincott Williams & Wilkins. 509pp http://vet.kku.ac.th/chaiwat/teaching/teaching2010
Objectives
Breeding soundness evaluation
Pedigree
Progeny test - Long time - More costly
Breeding soundness evaluation
Breeding Index
(USA TPI=Type production index)(Canada LPI= Lifetime profit index)(New Zealand BVS = Breeding values)(Japan NTP=Nippon total index)
Terminology of semenPTA (ETA) : Predicted or estimated transmitting ability EBV : Estimated breeding value (Canada)PTAT : Predicted transmitting ability of type traitsReliability
Factors on Semen qualityBulls effectFeeding DiseasesSemen collection managementEnvironmental effects
Bulls affecting Age Scrotal circumference Breeds Body condition score Physical abnormalities Frostbite ???
Effect of Age
Effect of Breeds
Effect of BCS
Effect of Physical abnormalities
Effect of Scrotal circumferenceMinimum Recommended Scrotal Circumference in Centimeters by Age for Bulls Age (months) Scrotal Circumference (cm) 15 30>15-18 31>18-21 32>21-24 33>24 34
Effect of scrotal frostbite
- Puberty --> scrotal circumference - semen collection time- Bull > 6 years- Boar > 3 years- Stallion > 20 years Feeding on semen quality
Feeding
NRC (National Research Council)
Young animals - Low energy --> delay semen production- Protein --> less affecting- High energy ---> low libido
Thailand --> Late puberty
- roughage- climates
Low feeding
- Testosterone --> decrease- low libido- Obesity --> low libido and sexual activity
Vitamin A
Pituitary gonadotropins
Testicular degenerationVitamin E ---> Male organVitamins
Minerals
- Iodine --> poor libido- Copper- Cobalt- Zinc- Manganese
Toxins - High gossipol --> epididymal cell
- radiation --> spermatogenesis
- estrogen feed ---> failure of sperm transport in the female tract
Diseases- Virus (IBR, BVD, FMD)
- Bacteria (Brucellosis)
- Parasite (Blood parasites)
Semen collection management
- Training- Frequency 1-2 per week- hoof problem--> electro-ejaculator
Environmental effects1. Temperature- Motility - Temperature shock- Heat shock- Cold shock2. Photoperiod & seasonLong time --> Longevity sperm
3. Oxygen ionO2 ---> H2O2
4. AciditypH 6.7- 6.9Sperm metabolism --> Lactic acids ---> Buffers5. Osmostic pressurePermeabiliity 6. Metal Lead, Mercury7. Bacteria 8. Detergent & Toxin
1. Semen collection
2. Storage and freezing
3. Storage and transportation
4. Thawing and inseminationRisk of environment factors
Bulls prepare- Shower- Wash prepuce with NSS 0.9 %Material prepare- Detergent- SterileCollection time- Light- TemperatureSemen collection
Storage and freezing1. Freezing 37 C 5 C -20 C - 79 C -196 C
2. Extender
- protection cold shock and cryo-protectant- Energy source- Buffering- Osmotic pressure- Bacteria inhibition
Extender Egg-Yolk Tris
- Tris ---> buffers- citric acid --> buffers- Glucose --> energy, osmotic pressure- Penicillin, Streptomycin, Polymixin B - Glycerol --> cryo- protectant- Egg-yolk --> cyro-protectant
Storage and Transport
Semen bank tank- coding- liquid nitrogenAI center tank- liquid nitrogen--> 2 weeksInseminator tank- liquid nitrogen --> day by day
Transports- Liquid nitrogen- Tank to tank - Canister - Straw (0.25 French mini-straw 0.5 ml USA)- < 15 second- forceps
Thawing and InseminationThawing- canister level- forceps- 35-40 C 30 second
AI- AI gun --> clean & dry
AI technique- Sperm death 10 -20 %
- Live sperm 6- 8 m. / straw
Progressive motile drop 5-15 %
Limited of bulls
Health control
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