Broiler offals were collected from small-scale processors (pluck shops) and cut into 10-cm pieces. The offal without feet, feathers or heads was ensiled in 22.5-l plastic buckets with sugarcane molasses varying from 0-500 g kg(-1). Molasses levels of less than 30 g kg(-1) ensilage mixture without added inoculant resulted in putrefaction. Molasses levels of 90 g kg(-1) and greater resulted in fermentation, and the pH after 48 h ranged from 4.60 to 3.95. The lowest pH of 3.95 was obtained after 48 h for a sugarcane molasses level of 90 g kg(-1) with the silage inoculant (Streptococcus fasecium, Lactobacillus plantanum and Lactobacillus acidophilus) added at 1 x 10(6) colony forming units (c.f.u.) g(-1) offal. This treatment was chosen to produce silage on a larger scale for feeding to crossbred (Large White X Landrace) barrows. The offal silage produced had the following contents: crude protein (n X 6.25) 281 g kg(-1) dry matter (DM), ether extract 486 g kg(-1) DM, crude fibre 5.1 g kg(-1) DM, nitrogen free extract 53.6 g kg(-1) DM and ash 41.1 g kg(-1) DM, Silage displaced 0, 100, 200 and 300 g kg(-1) DM of a commercial pig grower in the diet of growing/finishing pigs. The level of grower displacement by offal silage did not have any significant effect (P < 0.05) on feed intake, average daily gain or feed conversion. Values obtained for feed intake were 4.24, 3.99, 4.20 and 4.13 g per 100 g bodyweight (BW), respectively. Average daily gains were 680, 623, 670 and 648 g day(-1), while feed conversion values were 2.37, 2.37, 2.41 and 2.46, respectively. Pigs were slaughtered and assessed at the end of the feeding trial of 70 days but there were no significant differences among treatments (P>0.05) for bodyweight, dressing percentage, loin-eye area and backfat thickness at slaughter. Dressing percentage for 0, 100, 200 and 300 g kg(-1) DM silage fed was 69.5, 69.3, 70.2 and 69.9\% while loin-eye area was 25.0, 21.5, 26.4 and 23.7 cm(2). Backfat (P-2) values estimated were 18.4, 15.5, 18.8 and 21.6 mm, respectively. Composite blood count and plasma protein measured all fell within the normal range and no sign of ill health was noted during postmortem examination of carcasses. It was concluded that poultry offal silage can be used to replace up to 300 g kg(-1) DM of a commercial grower diet without affecting growth performance or the health of the animals. (C) 1997 Elsevier Science B.V.