2018/5/16. wagging. Cajoling

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1 Ch. 11 Goat Reproduction (p.71) 11-1 sexual maturity A. Puberty of goats (production of germ cells) B. Issues with goats breeding at too young an age -when to start mating? 60% of matured body weight -body maturity: no more huge fluctuations in body weight C. Puberty of sheep D. Factors influencing i puberty 1. age? 2. body weight ( organ development) 3. climatic condition: temperate vs. tropic 4. breeds 5. nutrition 6. heterosis 7. season (photoperiod) Breeding season (p.72) A. Not much in bucks, but can affect semen quality B. For does: mostly in the Fall and some in the early Spring ( short photo period) C. Late Fall mating vs. late Spring mating for milk market sale D. Breed differences: related to geographical origin (by Equator) 11-3 Estrous (p.73): changes in appearance and behavior before and after ovulation Time of estrous (heat) 1. Starting age & interval 2. Period of the year 3. Duration of estrous: -season effect? social impact? 4. Effect of nursing kids by suckling: anestrous for 4-10 wks 5. Resumption of estrous after kidding? (p.74) -First estrous=ovulation? -Early (January) vs. late (March, daylight ) kidding Signs of estrous (p.74) 1. Important timing basis for mating -arrangement for natural mating -artificial insemination 2. Appearance -clear mucous discharge, swollen vulva 3. Behavior -wagging tail -restless, walk more -reduction in feed intake and milk production -mounting activity wagging Cajoling Mating (p.74) -Daily frequency by buck: non-seasonal, semen quality multiple does with one buck (p.75) A. Kids born of known parents B. Buck economy C. Mating frequency not known D. Buck may be over-exhausted 5 5 1

2 Buck reproductive organ and anatomy multiple does with multiple bucks (p.75) A. Enhance herd conception rate B. Kids genealogy not certain C. No mating record D. Dominant bucks could be over-mating E. Common practice in meat goat herd single doe with single buck (p.75) A. Monitored estrus and mating by arrangement B. Can register all records for management C. Much more time- and labor- consuming D. Suitable for dairy operation comparison of the three mating methods? (p.75) 1. Which methods are good only for breeding purpose? 2. Methods appropriate for meat goats? 3. Better off for dairy goats? - Increasing conception rate by? 1. Strict selection of competent bucks: strong body with high libido 2. Flushing just before mating season: with high protein and beta-carotene feeds; avoid high lipid feeds 3. Adequate exercise to stay away fatty body 4. Make good use of breeding season 5. Not to over-exhaust bucks Pregnancy (p.76) A. Are does pregnant for sure? At early stage? 1. Estrous records 2. Temperament 3. Appearance B. Approaching parturition for certain in time? 1. Records 2. Milk yield 3. Appearance C. Pregnancy diagnosis 1. observation: no estrous 3 weeks after mating; overlooking? 2. Palpation on abdominal area: by experience; subjective 3. instrumentation: provide image evidence (1) Ultrasound: 60 days; (2) X-ray: <55 days Kidding (p.77) A. Doe appearance 1. Udder; 2. vulva; 3. ligaments B. Doe behavior: less prominent in older does 1. urination; 2. defecation; 3. nesting 侵入式

3 母羊尾根周圍之構造 坐骨 韌帶 脊椎 尾根 韌帶 坐骨 Birth Position, p Artificial insemination (p.79) Advantages A. Use less bucks in the herd B. Transportation of bucks and does for mating not necessary C. Increase conception rate? D. Make use of semen of disable bucks E. Decrease frequency of buck use (mating) F. Eliminate poor bucks, quick spread genetic merits via semen G. Prevent contagious reproduction diseases Disadvantages A. Require particular techniques and tools B. Systemic media of disease transmission C. Poor technique decreases conception rate and injures goats D. Need to observe estrous to determine insemination timing

4 AI operations (genetic upgrade) and lactation Doe reproductive organ and anatomy 乳量 乳脂率 ( 比率 ) 乳蛋白 ( 乳量 ) ( 母羊群中人工授精的比例 ) AI practice in France 11-8 Intersex (p.84) A. Goats with both part of male and female structures B. More often in Saanen than other breeds C. Tend to appear in polled (hornless) individuals D. a sex-linked recessive trait in goats and it s linked to the polled gene E. Pseudohermaphrodites: have testicular-like tissue but will be XX karyotype F. Usually no scrotum present and the testicles ti are located just beneath the skin G. They are not going to be producing sperm but they will produce testosterone. H. Smells like a buck but can t fertilize a female I. Judging? by appearance and behavior: Pseudohermaphrodites

5 Effect of shortening photoperiod on goat reproductive physiology (light hours nerve hormone behavior) Manipulation of goat reproduction suprachiasmatic nucleus 交叉上核 Cerebrospinal fluid 腦脊髓液 Estrous duration and mating plan in breeding season Mating Too early Ok Ideal Ok hour Start Clear Opaque mucus mucus Too late Pre estrus Estrus: mount standing Post estrus Ovulation 6 10 h 18 h 10 h 6 10 h Natural rhythm of doe Negotiations between doe reproductive activity and market demands of goat milk and meat in Taiwan 冬至 立春 夏至 Month Day time Mating estrus Kidding Peak milk Milk demand off off School off Meat demand Hot Warm Hot days Kids at 1 year old Key timing event: allow time for sperm to travel to oviduct just before ovulation Treatments to control breeding season-1 1. Use of photoperiod under artificial environment to control reproduction Artificial short photoperiod Artificial long photoperiod Buck testosterone increase decrease Doe ovulation start end 2. Elimination of seasonal change to control buck reproductive activity --buck are first treated with long photoperiod (16 h lighting/day, long day) 1 or 2 months, then switched to short photoperiod (8 h lighting/day, short day) 1 or 2 months. --Rotate the treatments will eliminate or reduce seasonal changes in sexual behavior and semen amount and quality. Treatments to control breeding season-2 3. Induction of buck reproductive activity out of breeding season --bucks treated with artificial long photoperiod and then apply melatonin or natural lighting (relative short day) can stimulate reproductive activity out of season. 4. Control of doe reproductive activity outside the season by buck effect: techniques to stimulate reproductive activity of does with seasonal no ovulation -bucks treated with photoperiod and have sexual activity can improve doe response to buck effect. -bucks after long photoperiod treatment can induce does without ovulation under natural lighting. -does treated with artificial lighting can improve response to buck effect

6 Bucks for natural mating (France) bucks isolated far away from does 2 months ahead of breeding season to enhance buck effect later on Reproduction control plans : artificial lighting (summer mating), melatonin implant (spring, summer), AI, natural mating 31 long day natural day AI natural mating Keys: approaching spring with increasing day, need to use melatonin (for doe) near summer with natural long day, need to use artificial lighting treatment plus melatonin (induce doe estrus in long day season) in both cases, use natural mating 18 days post AI, if needed 32 Doe heat detection for AI-1 (France) Individual doe heat detection with the aid of other goats -Intact bucks harnessed with apron and wax color stain box -vasectomized bucks harnessed with wax color box -Wethers treated with androgen and harnessed with color box -Does treated with androgen and harnessed with color box Doe heat detection for AI-2 (France) Group doe heat detection: lure by bucks -Intact bucks harnessed with apron, not in contact with does In estrus Buck with apron tethered outside doe pen Not in estrus Buck harnessing A doe mounted standing by a harnessed buck Doe heat detection for AI-3 (France) Group doe heat detection: intact bucks harnessed with apron and wax color box in close contact with does Not ( 未發情 in estrus ) Doe ( 塗有染劑 with color print 之母羊 on back) Buck ( 配戴圍裙與 with apron and 染劑之公羊 color box ) 35 6