Age-related features of compensatory growth and physiological adaptation in large white and landrace gilts under different weaning ages

Abstract

The aim of the study was to determine the effects of weaning age on growth intensity, adaptive capacity, feed intake, and the incidence of diarrhea in piglets of two maternal breeds – Landrace and Large White – with an assessment of their prospects for replacement gilt development. Four groups of piglets were formed according to weaning age: 21 and 28 days. The dynamics of body weight growth from birth to the end of the nursery period, the incidence of gastrointestinal disturbances, feed intake intensity, and the levels of average daily and absolute weight gains were evaluated. The results show that reducing the suckling period to 21 days leads to temporary growth suppression, decreased average daily gains from day 22 to 35 (in Landrace piglets to 34–144 g, and in Large White piglets to 86–136 g), and reduced absolute gains (0.24–1.01 kg and 0.60–0.95 kg, respectively), coinciding with peak diarrhea incidence and irregular feed consumption. At the same time, early-weaned piglets demonstrated compensatory growth after the adaptation period, particularly in Landrace gilts, indicating partial restoration of growth. Ultimately, the final body weight of early-weaned piglets was 3.8–7.3 % lower compared to those weaned at 28 days. Piglets weaned at 28 days exhibited more uniform growth dynamics, stable feed intake, and lower diarrhea frequency, which ensured more efficient adaptation to solid feed and improved feed conversion. Average daily gains from birth to the end of the nursery period were 383 g in Landrace gilts and 364 g in their Large White counterparts. Breed-specific traits also influenced adaptation: Landrace gilts showed more pronounced compensatory growth, while Large White piglets demonstrated more stable gains and feed intake. It was established that reducing the suckling period to 21 days significantly affects adaptation: early-weaned piglets show irregular feed intake and increased diarrhea incidence, which reduce growth efficiency in the first weeks post-weaning. Although compensatory growth occurs later, their final body weight remains lower than that of piglets weaned at 28 days. Conversely, optimizing weaning age to 28 days ensures more stable growth dynamics, uniform feed intake, reduced diarrhea, and improved economic efficiency. Thus, management of suckling period length is a key factor in raising healthy, productive, and resilient young pigs.