Rodent ranching
Adaptable and prolific, many rodent species have been and continue to be a delicacy in a number of countries. Not restricted to the tropics, dormice were favoured by the Romans and they are still eaten in parts of Europe, while squirrels are a choice game animal in the US. However, it is in Latin America, Africa and Asia where markets offer a particularly wide variety of rodent species for consumption and are often preferred over other meat sources. The vast majority of these animals are still gathered from the wild and several species have been hunted so extensively that they are now extinct or endangered. However, even with species that are plentiful in supply, the increasing demand for "bushmeat" offers small-scale farmers an economic incentive for raising these species in captivity.
Guinea-pig
Domesticated guinea pigs (Cavia porcellus) are an important meat source for Latin America
but their use has also spread to many parts of Africa and Asia. The low cost of raising these
animals makes them highly suitable for the landless peasant or urban dweller. They require little
space and can be raised in small cages or cardboard boxes, although many Latin American families
raise them loose within the home. Their feeding efficiency is high and better than most farm
animals, even when fed on kitchen scraps, garden wastes and weedy vegetation.
However, barley and alfalfa are grown
specifically for guinea pigs in some areas. Green forages and/or surplus fruits are particularly
essential as these animals area unable to synthesize vitamin C.
Guinea pig females are able to reproduce from three months of age and many domestic breeds are able to produce four litters each of 2-3 young a year. When grown for meat, the young are weaned at 3-4 weeks and are ready for market by 12 weeks of age. The meat fetches a good price in regions where it is popular: a guinea pig of 3-4 months weighing 1kg can be sold for twice the price of 1kg of beef, with production costs about 20-25% of the selling price of beef. The nutritional value of the meat is higher in protein (21%) and lower in fat (8%) than most other meats and there is also very little waste as the skin, head, bones, lungs, liver and intestines are often consumed with the meat. If the skin is not consumed, it may be used for the home manufacture of handbags, knapsacks, feed bags and slippers. The 'pelleted' manure is also used as fertilizer or as a feed ingredient for other livestock.
Guinea pigs are not labour intensive and, due to their docile nature, they can easily be managed by women and children. However, the successful production of these animals does require the development of specific husbandry skills which relate to breeding (to select superior stock and prevent inbreeding), feeding (including use of concentrates), housing and disease control. Training is available through short courses, extension activities and other technical assistance programs but more attention from government institutions and agricultural sector policy-makers should be directed towards research and rearing of these small animals.
Grasscutter
Otherwise known as cane rats, these rodents (Thryonomys spp.) are widely distributed and
valued in West and Central Africa. Like guinea pig, the meat is of a higher protein but lower fat
content than domesticated farm meat and it is also appreciated for its tenderness and taste. In the
past this animal has been hunted extensively although, in the savanna area of West Africa, people
have traditionally captured wild grasscutters and fattened them in captivity. More recetnly,
intensive production of grasscutters has been undertaken in countries such as Benin and Togo and
agricultural extension services in Cameroon, Côte d'Ivoire, Gabon, Ghana, Nigeria,
Senegal and Zaire have also encouraged farmers to rear these rodents in rural and peri-urban areas.
Research carried out over the last two decades has allowed the
selection and improvement of stock for captivity and much of the knowledge and techniques for
grasscutter production has been determined from work carried out at the Benin-Germany cane rat
breeding station, which was established in the mid-1980s. Practical information is now more readily
available for farmers interested in grasscutter production but training is still advised.
Unlike other rodent species, the high exploitation of grasscutters in the wild has not had a serious effect on its numbers. They have adapted easily to deforested areas and occur in close proximity to farmlands and people. However, there are areas where the species has been overhunted and savanna habitat is often at risk during the dry season from bushfires, which are lit during bushmeat hunting expeditions. Grasscutters are not the most prolific of rodent species but the high demand, attractive market price and the small amount of investment required makes grasscutters a suitable minilivestock activity for income generation in many parts of West and Central Africa.
(Information on grasscutters provided by F. Jori, CIRAD (Email: Ferran.jori@cirad.fi)
