L. Siefert and J. Opuda-AsiboDepartment of Veterinary Public Health and Preventive Medicine, Faculty of Veterinary Medicine Makerere University
P.O. Box 7062, Kampala, Uganda
Abstract
Introduction
Considerations for the intensification of goat production
Improved housing
Opportunities for and benefits of intensified goat production
Acknowledgement
References
Indigenous goats and traditional goat husbandry systems in Uganda are described. Intensive management is suggested for the benefit of certain social target groups. Corresponding husbandry, nutritional and health requirements and risks, particularly peracute clostridial diseases associated with high planes of nutrition and their management, are presented. Chemopro- and meta-phylaxis and vaccination programmes carried out in the isolation and zero-grazing units can substantially reduce reinfection and corresponding drug exposure of hosts and parasites, and eventual drug resistance of parasites. These could also reduce costs and drug residues in the host.
Intensification de la production caprine en Ouganda et gestion des risques sanitaires associés
Résumé
Cet article fournit une description des chèvres indigènes et des systèmes traditionnels de production caprine de l'Ouganda. Un mode intensif d'élevage profitable à certaines catégories sociales cibles est proposé. Les besoins correspondants en matière de conduite des effectifs, de nutrition et de santé et les risques liés à ce type d'élevage, notamment les clostridioses suraiguës associées à la conduite d'une alimentation hautement nutritive, sont ensuite exposés. Les traitements chimioprophylactiques et métaphylactiques ainsi que les programmes de vaccination réalisés dans des conditions d'isolement et de zéro-pâturage engendrent une diminution considérable des réinfections, donc de l'exposition des hôtes et des parasites aux médicaments, soit, à terme, de la chimiorésistance chez les parasites. Ils peuvent par ailleurs contribuer à réduire les frais ainsi que les résidus de médicaments chez l'hôte.
Goats in Uganda have not been artificially selected along breed characteristics to distinguish them phenotypically. Stiff natural selection over the years, however, has produced a population that could be better characterised by two phenotypes: the Small East African Goat which is a small and low weight type, and the Mubende which is a fairly heavy and tall type. Their spatial distribution is obviously not distinct and stunted growth resulting from marginalisation could obscure an otherwise better phenotypic performance. This is chiefly due to opportunistic breeding, feeding and husbandry methods. In 1963 the goat population was estimated to be 2.5 million compared to 0.8 million sheep and 3.2 million cattle (Jameson, 1970). Devendra and Burns (1970) compiled the following data on Ugandan goats: average birth weight of 2.1-2.4 kg; sexual maturity at four months with an average body weight of 14-15 kg; no seasonal breeding; three kiddings in two years with 10-30% twinning; and adult live body weight of 35 kg (range: 20-50 kg). Over 1.5 million goats and sheep were slaughtered in 1960 for human consumption and 1.4 million skins were exported. Jameson (1970) and Okello and Obwolo (1985) stressed the significance of goats as producers of meat, as it is generally preferred over other meats. Mubende goat skins are also of outstanding quality, but there is a prejudice against consumption of goat milk outside Karamoja. Socio-economically, goats play a traditional role as part of a dowry and, more recently, as a financial asset. Amann (1972) reported that a pound of goat meat fetched 50 cents more than beef and highlighted the suitability of a smaller carcass within a rural context. The average herd size ranges between 5-10 according to Sherman (1991).
Generally, traditional goat husbandry systems are determined by land availability, intensity of crop cultivation and availability of young family members or underpaid herdsmen to attend to the goats. Where the area of fallow and marginal land is comparatively small, tethering is the predominant practice, rather than extensive grazing and browsing on free range together with cattle. The characteristics of goat production systems are presented in Table 1.
Because of pressure on land due to an estimated 3% annual human population growth and reduced available child labour due to free primary education in the near future, extensive production methods will have to be replaced with intensive ones. This will require intensive research into potentials and limitations in order to utilise efficiently the abundant small ruminant resources in Uganda.
Table 1. Characteristics of traditional goat husbandry systems practised in Uganda.
|
Comparison Risks/requirements |
Tethering |
Zero-grazing |
|
Labour inputs |
low |
high <> very high |
|
Capital inputs |
negligible |
modest <> very high |
|
Land inputs |
marginal |
favourable |
|
Gains |
low |
high <> very high |
|
Controlled breeding |
unfavourable |
favourable |
|
Theft |
more likely |
unlikely |
|
Strangulation |
likely |
unlikely |
|
Dog attacks |
very likely |
unlikely |
|
Nutrition |
poor <> fair |
excellent |
|
Forage losses |
more likely |
less likely |
|
Plant poisoning |
possible |
unlikely |
|
Snake bites |
likely |
unlikely |
|
Management |
poor |
excellent |
|
Crop-owner conflict |
likely |
unlikely |
|
Environment damage |
likely |
unlikely |
|
Intensification |
risky |
controlled & low risk |
|
Health |
conditional |
good <> excellent |
|
Rabies (risk of infection) |
high |
low/nil |
|
Ticks and TBD-risks* |
high |
low/nil |
|
Helminth infection risks |
high |
low/nil |
|
Reinfection |
very high |
very low |
|
Fly attacks |
few <> many |
few |
|
Disease resistance |
promoted |
lost |
|
Drug exposure (H/P)** |
negligible |
low |
|
Drug resistance (P)*** |
negligible |
low |
|
Drug residues |
negligible |
low |
*TBD = tick-borne diseases
**H/P = host/parasite
***P = Parasite
Health risks management
Only clinically healthy individuals without any behavioural abnormalities should be selected. All goats kept under intensive regimes must be free from tuberculosis, brucellosis and certain other zoonotic diseases. Standard criteria for the interpretation of intradermal comparative tuberculin-test after inoculation of bovine and avian PPD, using the HauptnerTM test kit and reading results 72 hours later, are to date not available. Similarly, no conclusive evidence is available to verify the prevalence of brucella melitensis in Uganda (Nakavuma, personal communication, 1991).
It is advisable to vaccinate the goats twice within a fortnight against enterotoxaemia and other clostridial toxico-infections. Enterotoxaemia in particular has been a significant killer of goats. Any considerable intake of concentrates could precipitate this toxico-infection with only half an hour between the onset of clinical signs and peracute death, leaving no time for successful therapy. Covexin 8TM multivalent vaccine (Cooper) conferred at least partial protection against the aetiological agents types A and D of Clostridium perfringens. The incidence of the disease was reduced and the few affected suffered a more chronic course with more time for charcoal soda drench/intraruminal injection therapy (Thedford, 1990). However, many goats reacted visibly, forming sterile abscesses at the cervical hypodermic inoculation site of the vaccine.
The contagious ecthyma (Orf) epidemic proved to be another killer disease, predominantly of kids. Attenuated tissue-culture vaccine, non-pathogenic to human, is not yet available. Vaccination with this vaccine should be given priority since enterotoxaemia can be better controlled by delayed concentrate provision. Inoculation of fully virulent vaccine in a more suitable site could become a risky alternative because of the zoonotic properties of the Orf virus.
Table 2. Combined/alternative essential isolation measures.
|
Risks |
Identification |
Measures |
|
Ticks and tick-borne diseases (TBD) |
collection ante/post mortem |
Ivermectin TM SC or Deltamethrine percutaneous |
|
TBD |
parasitological |
chemo-vaccination |
|
|
blood/serum tests |
antibiotic metaphylaxis |
|
Tsetse/biting flies |
improved and treated traps collection |
reducing population and Deltamethrine percutaneous |
|
Trypanosomes |
parasitological blood-\serum tests |
drug availability? chemoprophylaxis/ prophylaxis/metaphylaxis? |
|
Mycoplasmoses |
clinical/serology |
LA-tetracyclines |
|
Clostridial toxicoinfection |
bacteriologically |
polyvalent clostridial |
|
|
GC VFA-pattern |
toxoid vaccine 2*3 ml |
|
Enterotoxaemia Tetanus, etc. |
|
6-week interval (and/2weeks ante partum) |
|
Contagious ecthyma (Orf) |
clinical/serology |
attenuated TC-vaccine |
|
|
|
no human pathogenicity |
Both ectoparasitosis (including nose-bots and tick-borne diseases) and roundworm endoparasitosis can be controlled by the injection of avermectine. However, it is not always available and costs may be prohibitive even when it is available. Ticks and flies (including tsetse) can be controlled by spot-on TM (Cooper) application and a suitable broad spectrum anthelmintic such as Fenbendazole or, where still active, Thiabendazole. Long acting tetracyclines can control subclinical infections, especially subclinical mycoplasmoses. Sufficient time should be allowed between individual measures and withdrawal periods must be observed.
Non-endemic diseases can attain epidemic proportions (in case of infections); this requires diagnostic monitoring and corresponding modification of isolation periods. Presently the period covers at least three weeks which seems insufficient for Orf. But since the viability of the virus is extremely high and of long duration, any extension of the isolation period becomes an economic issue. In Table 2, alternative isolation measures are presented in view of drug costs, ease of application and side effects.
Once the goats have been carefully selected and isolated, certain prophylactic and metaphylactic measures have to be taken into account: essentially, environmental control. Most parasites or their vectors requiring a suitable microenvironment can be successfully controlled by altering the environment to the parasites' disadvantage. Zero-grazing units offer a controlled environment. Smooth walls and clean concrete floors or deep litter that absorbs moisture and covers infective stages are not conducive to parasite survival and propagation. Once the animals have been cleared of parasites in the isolation unit they can be maintained on low challenge, providing the cut-and-carry fodder originates from an enclosed controlled area.
Two types of housing are proposed: a high cost, more durable type for high income groups and a low cost, less durable type for low income groups.
Low cost version
Roofing is similar to traditional grass thatched huts with an additional polythene sheath between the upper and lower grass or papyrus-mat layers at the lower edge of the roof. The plastic sheath can be folded and suspended to make a gutter for rain-water collection. The enclosure is made of scrap timber ensuring that the lower 50 cms of a 1.50 m fence is keeping the deep litter coffee husk layer of at least 30 cm inside. The animals are kept in pens (same height) and fed from troughs; water is provided ad libitum. No additional walking area is provided. Bedding must be changed when faeces and urine visibly accumulate; it provides excellent manure for crops and forage.
High cost version
Roofing is made from corrugated iron sheets. The surface is cement, and a cement walking area is provided. Resting places are roofed and have slatted floors. Feeding is from troughs and mangers. The unit should be cleaned twice daily and the sewage processed in a biogas plant before being used to fertilise crops and forage.
Improved feeding
Most of the provisions which proved useful in zero-grazing cattle systems have been experimentally adopted and are now under trial. Improved Pennisetum purpureum (Kawanda variety) cut as roughage at 1 m height, chopped to a length of approximately 5 cms and offered ad libitum is supplemented by not more than 1/3 Leucaena leucocephala to prevent mimosin intoxication. This browsing species is drought-resistant and apparently very palatable. A legume mixture of Desmodium intortum and Uncinatum, Centrosema pubescens, Macroptilium atropurpureum, Dolichos lablab and Stylosanthes spp. is readily taken as an enriched supplement. Keeping a feeding calendar would improve feeding management and cost effectiveness.
Farm-produced concentrates provide fresh, high quality meals vis-a-vis substandard commercial products. Like any new ration component, concentrates must not be introduced abruptly otherwise bloat (in case of overeating) or enterotoxaemia could cause death.
Some dairy cow farmers still find it wasteful to provide mineral supplements to their cows, but unlike game, the cows are confined or restricted in their movements. Therefore they are less able to seek mineral rich soils from which they can obtain their mineral requirements. This situation is worse with small ruminants and only free-range husbandry could allow goats to seek mineral-rich soils actively. However, geophagia increases the risk of lesions in the oral and gastro-intestinal tract linings and toxico-infection by clostridial pathogens. Kids born with signs of bone deformities which respond favourably to injectable mineral glucose depots or the provision of salt licks are an indication of this condition. Intensification must therefore provide for mineral supplementation either mixed in the ration or fed separately.
Multipurpose indigenous goat breeds respond well to the provision of crude rock salt blocks and, in particular, of compound MEN (M = mineral, E = energy, N = non-protein-nitrogen) salt licks.
Traditional or opportunistic husbandry systems produce hardy animals by natural selection; the potentials of this are not systematically exploited. Merely importing exotic breeds is not an effective exploitation measure. The few exotic goats which have found their way into Uganda as an adjunct to NGO (Non Governmental Organisation) sponsored zero-grazing cattle systems have been introduced without due consideration of the inputs required to meet expected outputs. Within opportunistic husbandry systems, the exotics (British Alpine, Toggenburger and Angora) cannot be expected to display superior performance.
The systematic exploitation of indigenous resources should serve as a good starting point. Selection of well adapted indigenous goats is imperative so that their adaptation to parasitic, nutritional and climatic stress can be fully exploited. This should be followed by education on scientific husbandry methods.
After the farmers have received training on the advantages of scientific husbandry methods, suitable exotic breeds should be selected along their adaptive and productive potential within each distinct environment e.g. tropical montane, dry savannah, moist savannah, rain forest and islands. They should then be performance-tested in controlled crossbreeding trials. Goats, like other small domesticated stock species (rabbits, poultry, fish), are excellent experimental material for studying indigenous resource potentials and utilisation alternatives. They could offer relevant and exciting exemplary learning and teaching alternatives in formal and adult education of farmers. Since women's ownership of goats is empirically much less contested in Uganda than the ownership of cattle, gender issues could be defused in a productive way in this vital socio-economic sector.
Intensified goat production could provide socioeconomic care and vocational training opportunities for over 1.5 million war-and AIDS-orphaned young people (equivalent to >10% of the total population).
Feedlot methods in or around cane plantations can utilise cane-tops and other by-products to promote offtake in seasonally overstocked areas. This makes better use of available biomass, which is often burned and does not need high capital investments.
GC-diagnostic typing was carried out in the Institute of Applied Biotechnology in the Tropics at the Georg-August-University Goettingen, Federal Republic of Germany; technical assistance of Prof Dr Seifert and Dr Habil Böhnel is gratefully acknowledged.
Editors' note
Readers interested in the composition of MEN salt licks should contact the authors.
Amann V F (ed). 1972. Nutrition and food in an African economy. Volume 1. Department Rural Economy, Makerere University, Kampala, Uganda. pp. 193, 205.
Devendra C and Burns M. 1970. Goat production in the tropics. Commonwealth Agricultural Bureau, Farnham Royal, Bucks, England, UK. pp. 13, 32, 35, 75.
Jameson J D (ed). 1970. Agriculture in Uganda. Oxford University Press, London, UK. pp. 114, 135, 318, 323, 342, 373.
Okello K L and Obwolo M J. 1985. Review of the potentialities of goat production. World Animal Review 5:27-32.
Sherman D M. 1991. Improved goat production in Uganda. Opportunities for the private and public sector. A concept paper. Tufts University School of Veterinary Medicine. North Grafton, Massachusetts 01536, USA.
Thedford T R. 1990. Goat health handbook. A Winrock. International information services publication. Winrock. International. University of Arkansas, USA. pp. 28-29.
