Effects of a novel maternal pheromone
Examining the performance and livability of weaned pigs
By Braden Steidley; Rebecca Robbins; Kassandra Wilson and John McGlone
Pigs experience unavoidable stress in commercial systems at weaning. A novel semiochemical or maternal pheromone (MP), that is produced by lactating sows has recently been reported and may have benefits for piglets in the post-weaning phase.
The MP is an odor of the mother that is typically absent in the post-weaning environment. When the MP was applied in a controlled post-weaning environment, pigs grew faster and fought less compared to control pigs.
The objective of this study was to add the MP back into the post-weaning environment, and determine the effects on performance and livability among weaned pigs in a commercial nursery with conventional production methods, wean ages and health challenges.
Materials and methodsFour sow sources filled eight rooms, with a total of 9,556 pigs, over a two-week period and they remained for about 47 d; rooms were blocked by sow source and randomly assigned to treatment (MP) or control treatments. Sow sources had similar yet variable health status (porcine epidemic diarrhea 2fvi, porcine reproductive and respiratory syndrome 2fvi, Mycoplasma and Influenza positive).
Weaned pigs averaged 21.9 days of age (range 18 to 25 d). Fence-line feeders were stainless steel, 48” in length, and a trough divided with 6 feeder holes per pen.
Three evenly spaced plastic strips infused with MP (0.0005% myristic acid and skatole) were placed 14 to 16 inches above the feed trough prior to pigs arrival and stayed for the first 48 hours. Control rooms were managed as usual for this farm (CON). An investigator was on site collecting gross pathology data for 19 days post-weaning.
Descriptive statistics were used to compare key performance indicators including average daily gain, end weight or adjusted 70 day weight, average daily feed intake, feed-to-gain ratio and livability between treatments.
ResultsTwo nursery rooms were identified as health challenged (N=2 rooms; 2,206 pigs) and summarized separately from the conventional groups (N=6 rooms; 7,350 pigs). Key performance indicators were approximately equal between MP and CON treatments among relatively healthy pigs.
Within the health challenged (HC) population, numerical differences between treatment groups were observed. The MP-HC group had a 92.06% livability, while CON-HC group had 87.86% (+4.2% difference). The MP-HC group had improved ADG (+10%), higher final weight adjusted to a common age (+4.9 lb./pig), lower feed intake (-25%), and improved feed efficiency (+12%) compared with CON-HC pigs.
Gross pathologic lesions were assigned to three categories: respiratory/systemic (68%), gastrointestinal (18%) and no gross lesions/unknown (14%). In addition, stomach fill amongst necropsied pigs was classified as full, partial or empty. The MP group had 63% full stomachs, 18% partially filled and 18% empty. The CON group had 54% full stomachs, 27% partial and 19% empty.
DiscussionDue to barns having variable health statuses, our findings were stratified by health status. Among conventional health rooms, data were variable, and we observed no differences in key performance or health measures between treatments.
The use of MP improved key performance indicators among health-challenged weaned pigs. Nursery pig performance and health may benefit from the use of MP, especially among pigs or barns with livability below about 97%.
Research is needed to better understand how to efficiently apply the MP within the nursery setting, the economic value of the use of a MP, and the mechanism of how MP may change pig behavior, performance and health in different phases of production.
References
1. Archer C, Garcia A, Henderson M and McGlone JJ (2022) Olfactory enrichment using a maternal pheromone improved post-weaning pig performance and behavior. Front. Vet. Sci. 9:965370. https://doi.org/10.3389/fvets.2022.965370
Steidley is a third-year student at Oklahoma State University's College of Veterinary Medicine. Robbins is a veterinarian with R.C. Robbins Swine Consulting Services. Wilson is a student research assistant and McGlone is a professor in the Department of Food and Animal Sciences, both at Texas Tech University.
