RT Journal Article T1 Short- But Not Long-Term Effects of Creep Feeding Provided to Suckling Piglets A1 Romero, María A1 De las Heras Molina, Ana A1 Muñoz, María A1 Calvo, Luis A1 Morales, José Ignacio A1 Rodríguez, Ana Isabel A1 Escudero Portugués, Rosa María A1 López Bote, Clemente José A1 Óvilo, Cristina A1 Olivares Moreno, Álvaro AB Fifty-eight litters (16 from primiparous gilts and 42 from multiparous sows) were used, with a total number of 750 piglets involved in the study. Birth weight was stratified into three groups: low (<1.02 kg; LBW), normal (1.02–1.62 kg; NBW), and high (>1.62 kg; HBW). A creep feeding diet was offered to piglets in a creep feeder in 29 litters from day 7 until their weaning. Piglet mortality was recorded daily. Traceability was ensured up to the point of carcass splitting and subsequent meat analysis. Each carcass was eviscerated and weighed individually. Sixty-nine piglets were selected for the microbiome analysis (35 from the control group and 34 from the creep feeding group). Feces samples from the rectum were obtained at three time points (three days prior weaning, a week after weaning, and before the slaughtering of the pigs). Mortality during lactation was influenced by birth weight, with LBW piglets exhibiting a six-fold higher mortality rate than HBW. Creep feeding did not impact piglet mortality. Heavier piglets demonstrated greater weight gain when subjected to creep feeding, while the growth potential of lighter piglets was reduced. Variation in creep feeding consumption based on birth weight also affected microbiome composition, with high-birth-weight piglets displaying higher alpha diversity than low- and normal-birth-weight piglets seven days after lactation. Alpha diversity is indicative of gut health, with higher values suggesting greater stability and adaptability to different feed sources. In conclusion, the immediate impacts of creep feeding appear to be most prominent during lactation and potentially early postweaning. These short-term effects are modulated by birth weight, with HBW piglets demonstrating the greatest benefits from the implementation of creep-feeding practices. AB Simple Summary:Creep feeding is a common management tool on pig farms designed to encourage dry feed intake and supply piglets with essential nutrients by providing a highly palatable and easily digestible diet. Currently, research results on the efficacy of creep feeding vary, possibly because numerous factors may influence its benefits during lactation. Therefore, the aim of this study was to gain a deeper insight into the consequences of creep feeding on short- and long-term growth, carcass quality, meat characteristics, and microbiome composition as a function of piglet birth weight. During the study, we did not observe any long-term effects of creep feeding on these parameters. The short-term impacts of this nutritional management technique were mainly concentrated on lactation and potentially in the early postweaning stages. These short-term effects were influenced by birth weight, as piglets with higher birth weights seemed to benefit more from creep-feeding practices. PB MDPI YR 2025 FD 2025-01-17 LK https://hdl.handle.net/20.500.14352/117355 UL https://hdl.handle.net/20.500.14352/117355 LA eng NO Romero, M.; Heras-Molina, A.; Muñoz, M.; Calvo, L.; Morales, J.I.; Rodríguez, A.I.; Escudero, R.; López-Bote, C.; Óvilo, C.; Olivares, Á. Short- But Not Long-Term Effects of Creep Feeding Provided to Suckling Piglets. Animals 2025, 15, 253. https://doi.org/10.3390/ani15020253 NO Author Contributions:Conceptualization, C.L.-B., L.C., C.Ó. and J.I.M.; methodology, M.R., A.I.R., R.E. and M.M.; software, A.H.-M., M.M. and R.E.; formal analysis, C.L.-B., L.C. and C.Ó.; validation, L.C., R.E. and C.L.-B.; investigation, A.H.-M. and A.I.R.; resources, C.L.-B., L.C., Á.O., A.H.-M., M.M. and C.Ó.; data curation, M.R., C.L.-B. and L.C.; writing—original draft preparation, A.H.-M., Á.O., C.L.-B. and J.I.M.; writing—review and editing, Á.O., A.H.-M., C.L.-B., A.H.-M., L.C. and M.R.; visualization, M.M., R.E. and A.I.R.; supervision, C.L.-B. and L.C.; project administration, L.C. and C.L.-B.; funding acquisition, L.C. and C.L.-B. All authors have read and agreed to the published version of the manuscript. NO COPISO Soria NO Industrias Cárnicas Loriente Piqueras NO Ministerio de Ciencia e Innovación (España) DS Docta Complutense RD 8 abr 2025