The effect of short term high feed intake on the onset of puberty in transported gilts

Abstract

We conducted a trial to determine whether energy flushing combined with transport, regrouping, and exposure to boars influences the onset of puberty. In a large pig production unit, 320 incoming gilts approximately 160 days of age were randomly divided into two groups. The FLUSHED group (166 gilts) were both transported and energy flushed, and the TRANSPORTED group (154 gilts) were transported only. After transport, gilts were housed in small groups exposed to boars across an aisle. Boars were moved daily to pens facing different groups of gilts. As estrus detection is difficult in gilts this young, it was not attempted, and the onset of puberty was determined at slaughter one week after transport. Reproductive organs were collected immediately after slaughter and examined that day. There were more follicles >4 mm and uterine mass was larger (P>.05) in the FLUSHED group than in the TRANSPORTED group. Adrenal gland weight, ovarian weight, and uterine length did not differ between treatment groups. In this trial using 160-day old gilts, energy flushing increased follicular growth and uterine weight, which are indicators of puberty in gilts this age.