Chapter 4

Management of rabbits in tropical developing countries

HOUSING

Flooring can be made of hard bamboo-like material slatted together. Bamboo flooring of this type is recommended for adult rabbits only, as young rabbits tend to slip on the smooth slats and can develop deformed legs. Splitting and weaving bamboo strips into a mat provides much better footing for all rabbits. The outer surface of the bamboo should face upwards in order to minimise damage from gnawing and to facilitate cleaning.

Nesting boxes can be constructed from thinner material or even from clay (Figure 7). Wire has many advantages (Ministry of Agriculture, 1973) when used for rabbit housing, especially for floors and the fronts of cages. It should be noted, however, that this material can rust rapidly in warm humid climates if not galvanised or if the galvanised coating is damaged. Possibly its most important use would be in making ties, as mentioned above.

A fence of bamboo can be constructed (Anon, 1972) to keep out dogs and predators. Both fencing and housing should be constructed so as to allow the free passage of air for cooling.

In areas where wind and rain are experienced, housing would have to be more solidly constructed, with shutters being provided in some cases. In Brazil, rabbits are kept in cages situated in open sheds, which have removable panels for wind and rain protection (Karlic, personal communication).

For feeding and drinking, containers made from cans, old bottles and cheap wooden trough ing can be used (Stamp, personal communication; World Neighbours, 1974). Clay can also be used for this purpose (Figure 8).

The above outline illustrates some of the more important points which have to be considered when constructing rabbit housing in developing countries. Simple housing using local materials similar to that described has already been used quite successfully in Ghana, Zaire and Tanzania.

The use of water sprays (Lipinsky, Collings and Litchfield, 1972) and even the installation of sprinklers (Templeton, 1968) in the rabbitry in very hot areas, where water supply is no problem, have been suggested. In more arid areas where the water supply is restricted, the construction of underground compartments with inspection hatches has also been suggested (Templeton, 1968). The latter would undoubtedly greatly assist in keeping rabbits cool in hot climates but would be relatively difficult to clean and could increase parasitic disease problems such as coccidiosis. Although this type of housing has been used in villages of countries such as Ghana, it is not encouraged there and is not to be generally recommended if alternatives are available.

DISEASE PROBLEMS

Domestic rabbits kept in tropical developing countries are of course prone to the common diseases which affect rabbits in other countries. These include coccidiosis, enteritis and pasteurellosis. Problems can be caused also by such external parasites as ear mites and chicken fleas (McNitt, personal communication). However, cleanliness and correct management, which does not necessarily have to be sophisticated or involve the use of expensive drugs, can be extremely effective in the prevention of disease (Stewart, 1974). With special attention and energy devoted to proper management and cleanliness, rabbit diseases should not cause any undue difficulties in rural areas of tropical developing countries.

FEEDING

Rabbit production in developing countries is commonly based on low cost feeding, using locally available feedstuffs. In any promotion of rabbit husbandry in these countries an emphasis on simple feeding methods should be maintained. In developed countries, compounded rabbit feeds were primarily developed to increase growth rate and to minimise labour requirements (Walsingham, 1972). However, in the tropical developing countries more important considerations would be to formulate cheap diets based on feedstuffs that are of little direct value as human food. Providing the rabbits are kept on a relatively small scale, diets based on green fodders can be fed without incurring high collection and transportation costs.

Current feeding practices vary widely in the tropics, depending on the types of feed material that are available locally, but, in general, feeding is based on fresh green forage and succulents. For instance, in tropical Africa, feeds commonly given to rabbits include grasses, e.g. Guinea grass (Panicum maximum) and stargrass (Cynodon dactylon); legumes, e.g. Kudzu (Pueraria phaseoloides), groundnut haulms and cowpea haulms; root crops, e.g. sweet potato leaves and cassava chips; and various herbs, e.g. Tridax procumbens, Euphorbia and Aspilla (Mamattah, personal communication). In Mauritius, herbs and grasses such as Tridax procumbens, Sonchus oleraceus and Sonchus asper constitute the staple rabbit feeds (Borland, personal communication), while in Nyanga, Zaire, rabbits are fed on vegetables grown in nearby plots with minimal dependence on cereals (Stamp, personal communication). Palm nuts have also been fed in Zaire as a source of vitamins (World Neighbours, 1974).

Rabbits may be maintained solely on green feeds together with household vegetable waste. However, careful management and balancing of diets is necessary. The two most common deficiencies encountered in such diets are of energy and protein rather than minerals or vitamins. Although the rabbit is by nature herbivorous, growth rates on forage based diets containing high fibre levels (upwards of 25 per cent) will be increasingly curtailed with increasing fibre level. This is due to the animal's inability to obtain sufficient digestible material to satisfy its energy demands. The nature of the fibrous components is also important; the greater the degree of lignification, the greater the reduction in the digestibility. In general, tropical species of grasses are less digestible than temperate species at the same stage of maturity and are often of low protein content. The feeding of forage legumes, cut at an early stage, could help to increase protein supply. Alternatively, a protein supplement may be provided, such as vegetable oil seeds or oil seed residues.

Better organised producers may provide a balanced supplement. In Brazil, maize, rice bran, soyabean, wheat bran, alfalfa, bone flour and molasses are used in addition to green fodder (Karlic, personal communication). In Malawi, maize bran (McNitt, personal communication) is widely used by rabbit producers and in Ghana and parts of Asia, rice bran is often used. In Nepal, for instance, where a group project has been set up to breed and distribute rabbits, the feed consists of ad lib grass plus limited amounts of a home mixed 20 per cent crude protein supplement made from maize, rice bran, soyabean, bone meal, salt and limestone (Karki, personal communication).

Agricultural by-products constitute a useful source of rabbit feeds. For instance: in Ghana, dried waste brewery malt and blood meal is fed in addition to such things as groundnut cake, coconut cake, wheat bran, rice bran and additives (eg common salt, palm oil and vitamin mix). Following initial investigations into rabbit nutrition in Ghana, the following rations have been suggested:

It should be pointed out, however, that rabbit producers in many other countries have not found it necessary to provide creep feeds.

As in the case of breeding (Chapter 4), feeding is best carried out in the early morning and in the evening, the coolest times of day when rabbits are naturally more active.

Despite recent interest in identifying the nutrient requirements of the rabbit for maximum growth and efficiency of feed conversion, the nutritional requirements of the rabbit are still not well known compared to those of other classes of domesticated livestock. Information concerning rabbit performance on forage based diets as compared to concentrate diets is even more scant. There is an urgent need to evaluate the feeding value of tropical forage species and other commonly used local feed sources. Work has already commenced on these problems in some tropical countries (Ministry of Agriculture, Jamaica; National Rabbit Project, Ghana) but a lot more information is required so that small-scale producers can be adequately advised as to the most suitable feed and feeding practices.

RABBIT BREEDS AND BREEDING IN THE TROPICS

At present there are many rabbit breeds being used for meat and skin production in the developing countries. The following list gives an indication of the great variety of breeds used (in addition to the numerous local strains) in some of the countries already discussed:

All of these strains of domestic rabbits are descendents of the European wild rabbit, Oryctolagus cuniculus. Although many of these are breeding successfully in various countries, the most popular breeds are the New Zealand White and the Californians. The latter breed in particular has been very successful in Nepal (where the climate is relatively cool). These two breeds are also the most popular in commercial rabbit industries in the developed countries. When the various production traits such as fertility, growth and feed conversion rates are considered, under commercial conditions, New Zealand Whites and Californians are amongst the better breeds available for meat production (Sandford, 1974; Bombeke, Okerman and Moermans, 1975). However, these breeds have been evolved in quite different environments from those in tropical developing countries. Consequently, there is considerable scope for improvement by breeding strains which are physiologically better suited to local tropical conditions. Once the foundation stock has been purchased, then strong emphasis must be placed on the development of such a breeding programme.

There are several tropical and sub-tropical rabbits species, such as the South African genus Pronalagus (4 species), the Ugandan Poelagus or the Brazilian Sylvilagus (S. brasiliensis), which are well suited to tropical conditions. Some of these varieties might be worthy of investigation as possible domesticants. To the author's knowledge, no attempt has yet been made to domesticate any of these species, although the genus Romerolagus (Mexico) has been bred in Jersey Zoo and the eastern cottontail, Sylvilagus floridanus, has been tamed in American zoos (Crandall, 1964). Plans have been made in Malawi to investigate the local Pronolagus crassicaudatus or Red Rock Hare. Such programmes are essentially long-term, however, and more useful and immediate results are likely to be achieved from the development of existing domestic strains.

In wild rabbits, maximum activity, including sexual activity, occurs at around sun rise and sun set (Mech, Heezen and Siniff, 1966; Rowley and Mollison, 1955). Stodart and Myers (1964) demonstrated the similarities of such behaviour patterns between wild and domestic rabbits; it has also been reported that domestic rabbits display a higher rate of successful mating when pairing takes place in early morning or late in the evening (Williams, 1972). By restricting breeding to these times, not only is the apparent natural cycle of activity of the rabbit being followed but the detrimental effects of high ambient temperature on the fertility of male rabbits in the tropics (Chapter 3) can also be minimised, particularly if mating takes place in the morning following a relatively cool night.