Solving the Heat Stress Problem

Transcription

1 Breeding Herd Education Series Timely, relevant & convenient learning Thank you for participating in SowBridge To start this presentation, advance one slide by pressing enter or the down or right arrow key. Solving the Heat Stress Problem Dr. Tim Safranski University of Missouri (573) OUTLINE -Quantify Heat Stress Problem -Describe Heat Stress Problem -Solving Heat Stress Problem SowBridge April 3, 2013 Quantifying the Heat Stress Problem Quantifying the Heat Stress Problem $300 million annually in U.S. St. Pierre et al., 2003 Seasonality costs me more than PRRS Steve Pollman, Director of Operations Murphy-Brown Western Operations Wild pig is a seasonal breeder temperature photoperiod other Annualized Mortality Rate (%) /14/05 2/2/06 3/24/06 5/13/06 7/2/06 Date 8/21/06 10/10/06 11/29/06 1/18/07 Steve Meyer 2 3 increased sow mortality delayed puberty weaker, shorter and more irregular cycles increased stillborns (if heat stress is late) decreased lactation feed intake decreased piglet growth increased weight loss prolonged WEI increased aborts and NIP Need I go on? 4 increased embryonic death (early) poor follicular development compromised oocyte quality larger impact on parity one females reduced sperm production reduced sperm quality (increase abnormal) reduced libido 5 1

2 2/10/15 Heat Stress ST RT RR Thermoneutral zone is - F at -% relative humidity Structure of the Testis Function in maturation of spermatozoa, fluid absorption 6 Spermatic Cord - ontains vas deferens, pampiniform plexus, external cremaster cmuscle nerves 7 Thermoregulatory Mechanism of Testis Rectal temperature: C (iboar 1) C (5Boar 2) Transport of sperm during ejaculation Caput Epididymis Vas Deferens Efferent ductules tubules absorb fluid Seminiferous Tubule Sperm producing cells - true germinal epithelium Maturation of Corpus spermatozoa Tunica Albuginea - connective tissue which holds testis together Scrotum Pampiniform plexus Cremaster muscle Tunica dartos muscle Pampiniform plexus: Convolution of veins and arteries for cooling blood entering testis Epididymis Final maturation and storage. Only sperm capable of fertilization Rete Testis Function in sperm transport from seminiferous tubules - tubules Cauda Epididymis Testis is 5 to 6 F cooler 8 9 Levis Effect of season on percent discarded ejaculates Stud2 Winter (%) Summer (%) A B C D % motility or % normal morphology was < % in ejaculates not used. 2means Spermatozoa Motility 10 are from ~ 2000 ejaculates / stud / season. (Flowers,NCR-57,2002, unpublished) 11 2

3 Morristown Hope Corya Pork Farms 2/10/15 Rectal temperature all days and averaged across time 12 Rectal temperature, o C TN-TN-TN HS-HS-HS SEM = Day of trial 13 Williams et al Midwest ASAS Meetings Respiration rate Feed intake Respiration rate, breaths per min.0 TN-TN-TN.0 HS-HS-HS SEM = Day of trial Trt P < Group NS Trt*group NS Day P < Trt*day P < Sow feed intake, kg TN-TN-TN 5.0 HS-HS-HS SEM = Day of trial Trt P < Group NS Trt*group NS Least squares means treatments denoted as TN-TN-TN, or HS-HS-HS where the series of abbreviations represent the environmental temperature (TN; 18 to 20 o C) or heat stress (HS; 24 to 30 o C) that the sow experienced in gestation-farrowing-breeding. 14 Least squares means for treatments denoted as TN-TN-TN, or HS-HS-HS where the series of abbreviations represent the environmental temperature (TN; 18 to 20 o C) or heat stress (HS; 24 to 30 o C) that the sow experienced in gestation-farrowing-breeding. 15 All FARMS 5 - Farm Summary, Indiana Herds SVS 5 - Farm Summary, All FARMS Indiana Herds SVS Pregnancy loss after 28-day increases Farm 1 Farm 2 Farm

4 Influence of season on 28-day pregnancy diagnosis NCR-57, herds Similar management, facilities, feed & genotype Detecting the Heat Stress Problem Goal: identify and fix it before a problem Rectal temperature of a sow F Reluctance to measure and record Affected by reproductive status Respiration rate of a sow breaths/minute at thermoneutral conditions At breaths per minute she is doing all she can Air conditioning Check and calibrate ventilation systems Use of exogenous hormones Feed accordingly (especially in lactation) Cool water at adequate flow Move only at coolest time of day Select genetic line acclimated to your climate Air conditioning Check and calibrate ventilation systems Fan controls Fan belts Curtains Inlets (open wide and no extras ) Drippers (0.8 gal/hour) Cool cells Mean rectal temperatures for sows in the Evaporative Cooled or Forced Air rooms - OVULATION - OVULATION Trt*time, P < PROGESTERONE PGF 2 a ESTROGEN PUBERTAL ESTRUS ESTRUS PG-0 can work here Matrix can be fed for any 14d here Figure 2. Porcine estrous cycle and timing of pharmacological interventions (adapted from Isom) 22 Martin et al Midwest ASAS Meetings Safranski and Moore 4

5 Use of exogenous hormones Label approved PG-0 Treat sows at weaning Know what will trigger stop Research setting, in semen or sow at insemination prostaglandin oxytocin Feed accordingly (especially in lactation) maximize feed intake wet feed? feed often or automatic/self feeders Water water water F vs F water can have almost two fold difference in intake At least one quart per minute Time of day & feed consumed Time % of total daily feed consumed Midnight to 6:00 am 24 6:00 am to noon 38 Noon to 6:00 pm 20 6:00 pm to midnight 18 Daily temperature cycle in 7ive gestation barns: July average Ambient temperature, o C Time of 24 h day Barn A Barn B Barn C Barn D Mean 89 lactating sows J Anim Sci 85 (Suppl 2):1 26 Do any moving during the coolest part of the day 27 Comparison of farrowing rate for two genetic lines by temperature at insemination Bloemhof et al., Demonstration of upper critical temperature differences for farrowing rate for two genetic lines by temperature at insemination Bloemhof et al.,

6 Conclusions Check cooling systems now Consider feeding options Measure sow comfort Cool water available Lower watt heat lamps in farrowing Alter schedule of movement Everything right every day. 30 6