Use of PG600 to Facilitate Achievement of Breeding Targets

R.N. Kirkwood¹ and S.C. Misutka²

¹ Alberta Pork Research Centre; AAFRD, 905 O.S. Longman Building, 6909-116 Street, Edmonton, AB, Canada T6H 4P2

² Lacombe Vet Centre, Lacombe, AB, Canada T4L 2G5

A 1200 sow start-up herd (PIC genetics) reported a problem of delayed puberty causing a failure to achieve breeding targets. A site visit determined that gilts in the replacement pool appeared well developed (>100 kg) and that the management of boar exposure was appropriate. Therefore, an intervention strategy employing PG600 was implemented. During a 19-d period, gilts in alternate pens received PG600 with remaining gilts serving as controls. Daily boar exposure continued for all gilts. At detection of estrus, PG600 gilts were assigned to be bred or allowed to cycle, depending on gilt breeding requirements. Control gilts were always bred at their first observed estrus. All breedings were by AI.

Of 247 PG600-treated gilts, 192 were estrous by 7-d. Of these, 154 were bred and 115 conceived. Of 39 non-conceiving gilts, 22 had regular returns and 17 had irregular returns. Of 38 non-bred gilts, regular and irregular returns were 24 and 14, respectively. During this time period fewer control gilts were bred (84 of 224; P<0.0001) but their conception rate was higher (P<0.002) than for treated gilts (90.5% vs 74.7%). Age at first service and entry to service interval were similar for bred PG600-treated and control gilts (186±1.7 vs 193±2.1 d and 40.1±1.3 vs 44.8±1.2 d for PG600-treated and control gilts, respectively).

Implication: These data indicate that the strategic administration of gonadotrophins (eg. PG600) will be effective for facilitating the achievement of breeding targets.