Abstract 298

Machin,-DH; Silverside,DE; Hector,-DA; Parr,-WH

Tropical Development and Research Inst., 56/62 Gray's Inn Road, London, WC1X 8LU, United Kingdom.

Animal-Feed-Science-and-Technology. 1986, 15: 4, 273-284; 29 ref.

The preservation of cattle carcass offal by autolysis in the presence of formic acid, the utilization by pigs of feed containing the preserved offal (ROH) and the evaluation of the carcasses of pigs produced, are described. ROH was produced from minced intestines, stomach, lungs and blood of cattle incubated for 7 days at 33øC with 3% by weight of formic acid. No pathogenic bacteria were isolated from the ROH and proximate and amino acid analyses showed it to be a good energy and protein source. Forty-eight crossbred pigs, each weighing about 28 kg, were individually given feeds containing from 0 to 21.2% ROH DM until they were slaughtered at 78 kg liveweight. No significant difference was noted in the performance or carcass quality of pigs fed on the different dietary treatments, but the carcass tended to become fatter as the ROH content of the feed increased. This was reflected in a wider spread of grading which was considered to be due to the inability to maintain uniform energy values of the diets, as the level of ROH increased, exacerbated by undervaluation of its energy content. The results show that ROH is palatable to pigs and can supply a large proportion of their dietary protein and energy requirements. The use of ROH may have particular application in situations where the quantity of ruminant offal available does not justify the production of meals. Since the technology is uncomplicated and inexpensive, the preparation and use of ROH would seem to have particular value for use in developing countries.