Sugar beet molasses for growing and fattening pigs

Abstract

Forty-eight pigs with a mean initial weight of 24 kg were given diets containing 0(A), 10(B) and 20% (C) sugar beet molasses to 50 kg liveweight. The experimental design was a 3×2×2 factorial which involved 3 diets, 2 breeds (Landrace and Landrace×Large White) and entire males or females. Pigs of the same weight on different diets were given daily amounts of feed providing the same amounts of energy, protein and most other nutrients. Daily liveweight gain was not significantly affected by diet type, breed or sex. The feed-coversion ratio of growing pigs given diets which contained 0, 10 or 20% molasses was 2.69, 2.95 and 2.90, and feed cost per kg liveweight gain was 41.4, 42.1 and 38.2 Greek drachmas, respectively. Diarrhoea did not occur with molasses in the diet. Forty-eight pigs reared from 50 to 90 kg liveweight were given one of 3 diets containing 10(B), 20(C) and 40% (C) sugar-beet molasses in a second experiment of 3×2×2 factorial design. Pigs of the same weight on all dietary treatments received the same amounts of crude protein and energy. Daily weight gains (g day −1) were 775(B), 765(C) and 702(D). Feed conversion ratio (kg/kg gain) increased with increasing level of molasses in the diet, but the cost of feed used for each unit of liveweight gain decreased. Chilled dressing proportion of the pigs was not affected by diet or by breed, but females had a significantly higher value than males. Differences in eye-muscle area were significant only between sexes, with female pigs having a greater area than males. Backfat area and backfat thickness were significantly different between breeds, with Landrace pigs having greater values than crosses. The sexes also differed, females being fatter than entire males. Carcass quality was not significantly affected by diet or sex. Total fat content was highly related both to the weight of subcutaneous and flare fat and to the mean backfat thickness of subcutaneous fat measured at three points at the last lumbar vertebrae. The percentage of lean cuts of the carcass was influenced by the breed and sex of the pig, with the crosses having a greater percentage of lean than the pure Landrace; males were leaner than females.