The feed conversion ratio of weaned rabbits : a preliminary study

Abstract

The rate of increase of feed intake and growth rate subsequently decrease, with intake stabilizing at around 12 weeks of age for current hybrid lines of domestic rabbit. Similarly to other mammals, the rabbit regulates its feed intake according to energy requirements. For a closed unit (maternity and fattening), this global FCR is defined as the kilograms (kg) of feed consumed per kilogram (kg) of rabbit produced. When the FCR is calculated in fatteners then the FCR is defined as the ratio of kg of feed consumed per kg weight gain of rabbits (finishing weight minus weaning weight). In addition to FCR, efficacy of the feed utilization is sometimes presented as feed efficiency. Feed efficiency is negatively correlated with dietary digestible energy (DE) content. A rabbit regulates its feed intake according to energy requirements, as for other mammals. Based on the relationship between dietary DE content and intake, an improved FCR can be obtained with diets of high energy concentration. However, due to the dietary fibre requirements of rabbits and the low digestibility of different fibre classes, rabbit diets have a low energy content (DE or metabolizable energy) compared to poultry and pig diets. A phase feeding programme, including higher energy concentration diets in the finishing stage, improves FCR. If mortality occurs in the early fattening stage, the economic FCR deteriorates only slightly. Before weaning, these rabbits have consumed feed and, moreover, the feed consumption of the mother has to be divided between fewer weaned rabbits. In rabbit meat production, as in other animal species, feeding costs represent the largest part of the production costs. Actually, the production costs of meat rabbits are twice as high as for broilers and 25-35% higher than in pigs. In efficient production systems, rabbits can turn 20 percent of the proteins they eat into edible meat. Rabbit meat production is therefore an attractive proposition, especially when the aim is to produce quality animal protein. For countries with no cereal surpluses, rabbit meat production is thus especially interesting. High grain pelleted feed was the type of feed used in the experiment. The rabbits were weighed on a daily basis from weaning to slaughter. Temperature and humidity were also recorded. Rabbits have a constant internal temperature so heat production and losses must vary to maintain the body temperature. They do this by modifying their feed intake level. Rabbits are sensitive to very low humidity (below 55%) but not to very high humidity.