Effect of dexamethasone injection at birth on growth

Swine Day 2002
EFFECT OF DEXAMETHASONE INJECTION AT BIRTH ON GROWTH
PERFORMANCE OF PIGS FROM BIRTH TO WEANING
M. G. Young, M. D. Tokach, S. S. Dritz1,
R. D. Goodband, and J. L. Nelssen
system necessary for maintaining life and op- timal growth in the extra uterine environment. A total of 82 litters were used in a 21-day The prepartum surges in glucocorticoids in study to evaluate the effect of injecting litters swine have been shown to be an important of pigs with dexamethasone within 24 hours mediator of intestinal maturation and function. of birth on growth rate from birth to weaning. They also suggested that the glucocorticoid Experimental treatments consisted of an injec- role in intestinal maturation and function is tion of 1 mg dexamethasone solution (2 most likely limited to the immediate perinatal mg/mL, Prolab Ltd, St. Joseph, MO) to all period. pigs within a litter, while pigs in control litters did not receive a dexamethasone injection. There was no difference in growth rate from USDA’s Agricultural Research Service and birth to weaning between pigs injected with the University of Missouri, pigs were injected dexamethasone and control pigs. Number of intramuscularly with either sterile saline (Con-pigs weaned per litter and preweaning mortal- trol; n=10 males and 10 females) or a dexa- ity were not different. In this study no benefit methasone solution (dexamethasone, Phoenix was observed in growth rate from birth to Pharmaceuticals, Inc., St. Joseph, MO, 0.5 weaning from injecting whole litters of pigs mg/lb body weight; n=10 males and 10 fe-with 1 mg/pig of dexamethasone within 24 males) within one hour of birth. Pigs injected hours of birth. with dexamethasone grew 12% (0.63 vs 0.56 lb/day) faster during the 18-day lactation pe- (Key Words: Dexamethasone, Pigs, Growth riod. Pig weights at weaning averaged 15.5 lb Rate.) for the dexamethasone and 14.1 lb for the con- trols. Therefore, the objective of the present Introduction
study was to determine if the benefits in study could be replicated in a more commer- souri have found that the early neonatal period cial production environment. This environ- may be an opportune time to alter physiologi- ment includes injecting whole litters of pigs at cal factors that influence growth. In swine, the time of processing within 24 hours of there is an increase in maternal circulating birth. Also, since pigs are rarely weighed at cortisol, as well as a final fetal cortisol surge birth a more practical dosing scheme of 1 during labor. This elevation in fetal cortisol mg/pig was examined. may trigger the adjustments to the endocrine 1Food Animal Health and Management Center. Procedures
(Prolab Ltd, St. Joseph, MO). In the second treatment, pigs were processed according to This study was conducted in the KSU standard practice and did not receive dexa- Swine Teaching and Research Center’s far- methasone injection. The standard pig proc- rowing facilities. A total of 82 litters were essing practice was that pigs had their needle used in the study, with approximately 41 lit- teeth clipped, tails docked, ears notched and ters per treatment. The sows used in the study were injected with 1 ml/pig iron. All fostering were PIC Line 42 and were farrowed in three that took place did so after processing and groups of approximately 30 sows per group. within the first 24 hours after birth. Pigs were All sows were weighed entering the farrowing only fostered across litters within treatment. house and again at weaning. Sows were ran- At fostering, gilts and sows were standardized domized to treatments based on parity and with 10 pigs. Pigs were weighed individually weight entering the farrowing house on day at birth and again at weaning. Any pigs re-110 of gestation. Sows were provided ad libi- moved from the trial were recorded along with tum access to feed and water and feed intake their date of removal and weight. Data were was recorded. All sows were fed a standard analyzed using the mixed procedure of SAS. lactation diet formulated to contain 0.90% ly- sine, 0.90% calcium, and 0.80% P (Table 1). Results and Discussion
No sows were treated with dexamethasone during the trial. As expected, pig birth weight was similar for the dexamethasone and control treatments Table 1. Lactation Dieta
(Table 2). From birth to weaning, neither ADG nor weaning weight differed between the two treatments. The number of pigs on day 1 of the trial, at weaning, and removed from the trial was also similar for the dexa- methasone and control treatments. Prewean- ing mortality averaged 8.3% for the dexa- methasone and 8.5% for the control treat- ments. Sow weight entering the farrowing house, at weaning, and weight loss in the far-rowing house, lactation length and backfat at farrowing did not differ between treatments. In conclusion, we observed no benefit in growth rate from birth to weaning for pigs in- Diets were formulated to contain 0.90% ly- pared with the control pigs. The results do not agree with those of the recent USDA study where half the litter of pigs was injected with There were two experimental treatments. 0.5 mg/lb body weight within one hour of In treatment one, all pigs within a litter were birth. In that study pigs injected with dexa- injected with 1 mg/pig of dexamethasone methasone grew 12% (0.63 vs 0.56 lb/day) when the litter was processed, which was faster during the 18-day lactation period. Pig within the first 24 hours after birth. The dex- weights at weaning averaged 15.5 lb for the amethasone used was a 2 mg/mL solution dexamethasone injected pigs and 14.1 lb for the control pigs. There were a number of dif- obtained in the USDA study, but we modified ferences between the two studies. First, we some techniques in order to make our study injected whole litters of pigs with dexa- methasone whereas in the USDA study, they injected half the litter with dexamethasone and Other research by University of Missouri the other half of the litter with sterile saline demonstrated that a 0.9 mg/lb body weight of solution, which served as the control. Sec- dexamethasone given within 24 hours of birth ondly, in the USDA study they injected pigs significantly improved pre- and postweaning with 0.5 mg/lb of body weight of dexa- performance of barrows with no beneficial methasone, whereas in our study we injected effect on gilts. Similar to our experiment, two piglets with approximately 0.3 mg/lb of body other experiments carried out by the Univer- weight. Thirdly, the source of dexamethasone sity of Missouri in commercial production used in the USDA study was supplied by conditions failed to detect improvements in Phoenix Pharmaceuticals, Inc., St. Joseph, preweaning performance. We failed to obtain MO, whereas the dexamethasone solution a benefit in growth rate from birth to weaning used in our study was supplied by Prolab Ltd, by injecting litters of pigs with dexamethasone St. Joseph, MO. Finally, in the USDA study, within the first 24 hours of birth. Therefore, it they injected pigs within the first hour of birth appears that the benefits of injecting pigs with whereas in our study we injected pigs within dexamethasone within the first hour of birth the first 24 hours of birth. In our study we are inconsistent, with no benefit observed in attempted to simulate the growth performance Table 2. Effect of Dexamethazone Injection at Birth on Performance in the Farrowing House
Treatment
Item Dexamethazone1 Control2 SEM P< 1All pigs within a litter were injected with 1 mg of Dexamethasone within 24 hours of birth. 2Pigs were not injected within Dexamethasone.

Source: http://www.asi.k-state.edu/doc/swine-day-2002/dexpg20.pdf