An overview of hourly rhythm of demand-feeding pattern by a controlled feeding system on productive performance of lactating sows during summer

Abstract

The present study investigated the impacts of the conventional feeder and free feeding time (FFT), and backfat thickness (<20 mm and ≥20 mm) on sows at farrowing to weaning during the summer season. A total of 56 crossbred sows were allotted to one of four treatments according to a 2 × 2 factorial arrangement. Feeder type affected body weight changes (p < .01) and backfat losses (p < .05), and the body weight changes (p < .05) and backfat losses (p < .01) of sows were lower for those with <20 mm backfat thickness compared with those with ≥20 mm backfat thickness during the lactation period. Daily feed intake was greater in sows with lower backfat thickness (5.47 kg; p < .01) and sows in the FFT group (5.46 kg; p < .05). A greater average daily gain was observed in sows in the FFT group (p < .05). There were no effects of feeder type or backfat thickness on weaning-to-oestrus interval, blood urea nitrogen, glucose, triglyceride, creatinine, FSH and LH, or colostrum and milk composition for sows during lactation. There was a linear increase in the count of Lactobacillus spp. and coliforms in conventional feeders over time (p < .01). A linear increase was detected for acetic acid production in the conventional feeders over time (p < .01). Hence, it was concluded that controlling sows’ feeding leads to improved feed intake for sows housed in hot ambient temperatures during the summer period.