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Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 2/7/2013 Publication Date: 5/1/2013 Citation: Vallet, J.L., Miles, J.R., Rempel, L.A. 2013. Effect of creatine supplementation during the last week of gestation on birth intervals, stillbirth, and preweaning mortality in pigs. Journal of Animal Science. 91(5):2122-2132. Interpretive Summary: Reports estimate that 5 to 10% of otherwise healthy piglets are stillborn and that a further 10 to 20% of piglets that are alive at birth do not survive to weaning. This represents a major inefficiency to swine production. Previous results also indicated a relationship between delays in the birth process and stillbirth and preweaning mortality, but few strategies or treatments are currently available to reduce delays in the birth process. Other studies indicate that the energy metabolism of newborn piglets has a profound effect on survival to weaning. Finally, reports also indicate that creatine supplementation improves athletic performance for strenuous, highly repetitive activities. This is due to the role of creatine in the regeneration of adenosine triphosphate, which is the energy source required for most muscle activity. We hypothesized that creatine supplementation of pregnant pigs would accelerate the birth process and reduce stillbirth and preweaning survival. In addition, a secondary hypothesis was that creatine supplementation of the mother would improve creatine availability in the pig fetus, altering development and improving activity levels of piglets at birth. Pregnant pigs received supplemental creatine from day 110 of pregnancy until they gave birth (average 116 days), and the birth process was monitored with video cameras to measure the times of the birth of each piglet. Stillbirths and preweaning mortality of piglets was recorded. A subset of piglets was measured for changes in brain myelination to determine whether creatine supplementation of the mother altered myelination in the piglets. Results indicated subtle effects of creatine supplementation on the birth process, improving only the birth interval of the last piglet born. Creatine supplementation also improved myelination of specific brain regions. Creatine supplementation reduced the number of low birth weight piglets crushed by the sow (a common cause of piglet preweaning mortality) but did not affect overall stillbirth or preweaning survival rates. Technical Abstract: We hypothesized that creatine supplementation would reduce birth intervals, stillbirth rate, and preweaning survival in pigs because of its reported improvement of athletic performance in humans. In Exp. 1, gilts (n = 42) and first parity sows (n = 75) were mated at estrus. Beginning on d 110 of gestation, dams received either no treatment or 20 g creatine daily until farrowing. At farrowing in November 2008, pigs were monitored by video camera to determine individual piglet birth intervals. On d 1, piglets were weighed, euthanized, and the cerebellum, brain stem, and spinal cord were collected from the largest and smallest piglets in each litter to measure myelin basic proteins and myelin cholesterol, glucocerebrosides, phosphatidylethanolamine, phosphatidylcholine, and sphingomyelin. Preweaning mortality of the remaining piglets was recorded, including whether a piglet had been overlayed by the dam. A second experiment was performed using gilts (n = 90) farrowing in July 2010 to test the differential effects of creatine supplementation during hot, humid weather when dams typically have more difficulty farrowing. Once again, gilts were provided either no supplementation or 20 g creatine daily from d 110 to the day of farrowing. Gilts were video recorded during farrowing, piglets were weighed on d 1, and preweaning mortality (including overlays) was recorded. In Exp. 1, creatine supplementation had no effect on birth intervals or stillbirth rate. Creatine supplementation improved the amount of myelin lipids in brain regions of piglets, particularly the brain stem. Creatine supplementation also reduced overlays of low birth weight piglets from gilts but not second parity sows. Data from Exp. 2 were combined with gilt data from Exp. 1 to examine the effect of creatine, season, and their interaction. There were no effects of treatment or season on birth intervals, stillbirth rates, or overall preweaning mortality. Creatine treatment reduced the incidence of overlays in low birth weight piglets in the combined data set. These results suggest that creatine supplementation improved myelination and may have improved the ability of low birth weight piglets of gilts to avoid being crushed by the dam. |
