Handling Associated with Drenching Does Not Impact Survival and General Health of Low Birth Weight Piglets

SIMPLE SUMMARY: In the modern pig industry, one of the main goals has been to increase litter sizes, and thus, improve sows’ production efficiency. However, this increase in litter size has also resulted in an elevated number of low birth weight piglets and a higher perinatal mortality. In an attempt to reduce mortality in low birth weight piglets, many studies focus on drenching bioactive substances. However, most studies only focus on the supplement and neglect any potential effect of drenching itself. Given that low birth weight piglets are often very weak, drenching might provoke additional stress, and consequently, nullify the effect of the supplement or even negatively affect the piglet’s health. In this study, low birth weight piglets were sham drenched by conducting the drenching act without a liquid (putting an empty syringe into the animal’s mouth) to evaluate the effect of drenching on their body weight, health and mortality. No negative or positive effect of drenching was observed, and thus, it was concluded that drenching is a safe tool that can be implemented in good pre-weaning management. However, studies that examine the oral supplementation of bioactive substances should always include a sham and a negative control group to ensure that the observed results can be attributed to the supplement, rather than the act of drenching. ABSTRACT: The increase in litter sizes in recent years has resulted in more low birth weight (LBW) piglets, accompanied by a higher mortality. A potential intervention to overcome this is drenching bioactive substances. However, if the act of drenching provokes additional stress in LBW piglets, it might counteract the supplement’s effect and be detrimental for the piglet’s survival. To study the effect of the drenching act, piglets from 67 sows were weighed within 4 h after birth. The mean litter birth weight (MLBW) and standard deviation (SD) were calculated. LBW piglets (n = 76) were defined as weighing between (MLBW-1*SD) and (MLBW-2.5*SD). They were randomly allocated to two treatments: “sham” (conducting the act of drenching by inserting an empty 2.5 mL syringe in the mouth during 20 s, once a day, d1 till d7; n = 37) or “no treatment” (no handling; n = 39). On day 1, 3, 9, 24 and 38, piglets were weighed and scored for skin lesions. Blood samples were collected on day 9 and 38 and analyzed to determine glucose, non-esterified fatty acids (NEFA), urea, immunoglobulin G (IgG), insulin-like growth factor 1 (IGF-1) and a standard blood panel test. There was no difference between sham drenched and untreated piglets regarding any of the parameters. In conclusion, this study showed that drenching does not impose a significant risk to LBW piglets and can be applied safely during the first 7 days after birth.