Carcass and economic value of rabbits raised on ripe <i>Gmelina</i> fruit pulp based diets

Abstract

Carcass and economic indices of rabbits fed dietary ripe Gmelina fruit (RGFP) pulp were assessed. Sixty rabbits, aged six weeks (New Zealand White x Chinchilla cross) of mixed sexes (25 males and 35 females) were shared into five groups of 12 animals each and balanced on sex and initial weight and randomly allotted to the five experimental diets. Maize, the only energy source of diet I was replaced with 25, 50, 75 and 100% RGFP in diets II, III, IV and V, respectively in the 16 weeks trial. Carcass characteristics were determined pre-chill. Completely Randomized Design, one-way analysis of variance was used and significant (p<0.05) means were separated using least significant difference. The cost of feed (N/kg), cost of feed consumed (N/animal), cost of feed per weight gain (N/kg weight gain), final weight, fasted weight, percentage weight loss, dressed weight and dressing percentage ranged from 55.07 – 28.21, 407.07 – 213.55 and 307.68 – 207.34, 1900 – 1605g, 1884.90 – 1589.78g, 15.23 – 15.09%, 1206.42 – 1017.46g and 64.01 – 63.97%, respectively. As a percentage of the dressed carcass, the shoulder, loin, rack, thigh, head, tail, belly fat, lung, kidney, liver and heart weights (g) ranged from 33.53 – 33.47, 8.97 – 8.74, 6.28 – 6.18, 35.29 – 35.16, 5.20 – 5.13, 3.29 – 3.19, 3.30 – 2.89, 0.32 – 0.30, 1.50 – 1.47, 2.80 – 2.77 and 0.18 – 0.15, respectively. Diet I had the highest cost of feed, cost of feed consumed, cost of feed per kilogramme weight gain, pre-slaughter weight and percentage belly fat, while diet V had the least values of the above parameters except percentage belly fat and dressed weight. Also, the values for these indices decreased as dietary RGFP increased. Though undesirable, the meat of control rabbits was the fattiest. Dietary inclusion of RGFP did not affect percentage weight loss, shoulder, loin, thigh, head, tail, lung, kidney, liver, heart and dressing percentage. For optimal returns on investment, RGFP may not replace above 75% of maize in rabbit diets.

Keywords: Rabbit, New Zealand white x Chinchilla cross, Gmelina, Fruit pulp, Carcass, Economic value