Tuberculosis and brucellosis prevalence survey on dairy cattle in Mbarara milk basin (Uganda)
Introduction
Milk consumption is increasing in many southern-hemisphere countries and especially in Africa (Delgado et al., 1999, Faye and Alary, 2001). In Central and Eastern Africa, higher milk production is observed around the major towns to supply the urban populations. In Uganda, the highlands around Mbarara in the south-western part of the country have a temperate climate and are particularly well adapted for milk production. A recent survey (Dabusti and Vancauteren, 1998) identified five types of dairy farmers from pastoralists with Ankole cattle (a local breed) in extensive lowlands to modern specialized dairy farmers with pure Holstein cows in the highlands. Most of the farmers between those two groups had diversified activities (primarily coffee or banana).
At the same time, human tuberculosis and brucellosis is increasing in populations with high prevalence of HIV—especially in Africa (Raviglione et al., 1995). TB and brucellosis are the major zoonotic diseases that can be transmitted through the cow's milk. According to the Ugandan Ministry of Health, the mean annual incidence rate of human TB was 1.34/1000 person-years in Uganda for 1995. However, the role of Mycobacterium bovis was not known. The human brucellosis incidence rate was officially 0.7/1000 person-years in 1995. The current tuberculosis and brucellosis status in dairy cattle is not well known in Uganda. We did a prevalence survey of a randomly selected population of dairy farms in a district of Uganda to assess the importance of those zoonotic disease in the milk basin of Mbarara (the main milk-production area in Uganda). The associations of animal characteristics (gender, age, breed) with prevalences of tuberculosis and brucellosis was assessed.
Section snippets
Study area
The Mbarara district represents 5% of the whole area of Uganda (i.e. 10839 km2). This district has a common border with Rwanda and Tanzania in the southern part. Mbarara is located in the south-west part of Uganda and has a mean altitude of 1200 m above sea level. The eastern part of Mbarara district is lowlands and the western part is highlands. The climate is equatorial temperate (especially in the highlands). The mean minimum and maximum annual temperatures are 14.6 and 26.3 °C, respectively.
Tuberculosis
The participation proportion of the survey was 340/396 herds (86%). The difference from the sampled herds was due to (i) the absence of cattle in 26 farms for various reasons (lack of manpower, cattle sold for dowry, moving, deceased), (ii) the lack of time for achieving the survey before the rainy season in 22 farms from the agro-pastoral zone, and (iii) the farmer's refusal in eight farms. In the pastoral zone, 121 herds were tested, and 219 in the agro-pastoral zone.
The size of the herds
Discussion
Because no available or convenient data are published in the Mbarara district on TB and brucellosis prevalence, our data cannot be compared easily with previous studies. The official data from Office International des Epizooties (OIE) mentioned 640 cases of bovine tuberculosis in Uganda in 1997 (OIE, 2003). Unpublished data from the Mbarara slaughterhouse mentioned 76 cases of affected animals with TB i.e. 2.2% of the slaughtered animals in 1997 but 1.07% in 1999. However, no disease control
Conclusion
We found apparent prevalences of infection of 6% and 15.8% (animal-level) for TB and brucellosis in an important dairy-cattle area of Uganda. There were higher prevalences among females than males, and among older than younger animals (all uncorrected for clustering). More than half the herds sampled had positive animals. Positive animals were more typical in the more intensive wetler agro-ecologic zone.
Acknowledgements
The present study was supported by the French Embassy in Uganda. Special thanks are addressed to Mrs Michele Baherle for her support to this programme and to S.E. J.B. Thiant, Ambassador of France in Uganda for his interest in this survey. We are also grateful to the Ugandan partners from local veterinary services and local authorities for their help and contribution, and to the farmers from Mbarara district.
References (41)
- et al.
A prevalence study of bovine tuberculosis and brucellosis in Malawi
Prev. Vet. Med.
(1993) - et al.
Prevalence of tuberculosis in cattle in the Dangme-West district of Ghana public health implications
Acta Trop.
(2000) - et al.
Seroprevalence of brucellosis in cattle and humans in the Akwapim-South district of Ghana: public health implications
Acta Trop.
(2000) - et al.
Problems associated with tuberculosis and brucellosis skin-test methods in Northern Cameroon
Prev. Vet. Med.
(1993) - et al.
Risk factors for brucella spp. Infection in dairy cattle farms in Asmara
Eritrea. Prev. Vet. Med.
(2000) Bovine tuberculosis: a general review with special reference to Nigeria
Vet. Bull.
(1976)Etat actuel de la tuberculose bovine en Afrique et au Moyen-Orient
- et al.
Enquête sérologique et allergologique sur les bovins du Niger
Rev. Elev. Méd. Vét. Pays Trop.
(1991) Recherche sur les causes de mortalité des veaux dans la savane sous-soudanienne du nord de la côte d’Ivoire
Bull. Epizoot. Dis. Afr.
(1971)Enquête sur les prévalences de la tuberculose et de la brucellose dans le cheptel bovin du bassin laitier de Mbarara (Ouganda)
Thèse Méd. Vét., Créteil.
(2003)
Enquête sur certaines zoonoses en République de Djibouti I. Chez les ruminants à l’abattoir de Djibouti
Rev. Méd. Vét.
Les systèmes d’élevage du district de Mbarara et leur contribution à la filière laitière. Mémoire de Master développement agricole tropical
Epidémiologie de la tuberculose et de la brucellose bovine des bovins en zone périurbaine d’Abéché
Tchad. Rev. Elev. Méd. Vét. Pays Trop.
Livestock to 2020. The Next Food Revolution
Contraintes hygièniques et sanitaires de la filière lait dans le district de Mbarara en Ouganda. Etude et proposition d’actions pour la maîtrise de la qualité du lait.
Thèse Méd. Vét. Nantes.
Veterinary Epidemiology Research
Enquête sérologique sur la péripneumonie et la brucellose bovine en Ethiopie
Rev. Elev. Méd. Vét. Pays Trop.
La brucellose bovine en Afrique Centrale
Rev. Elev. Méd. Vét. Pays Trop.
La brucellose bovine en Afrique centrale Résultats statistiques des enquêtes menées au Tchad et au Cameroun
Rev. Elev. Méd. Vét. Pays Trop.
Bovine brucellosis in Nigeria
Vet. Rec.
Cited by (84)
Profile likelihood confidence interval for the prevalence assessed by an imperfect diagnostic test
2023, Preventive Veterinary MedicineEpidemiological investigation of brucellosis in breeding female cattle under the traditional production system of Jimma zone in Ethiopia
2020, Veterinary and Animal ScienceCitation Excerpt :however, this result is lower than the reports of Megersa et al. (2011) 26.1% in southern and eastern Ethiopia and Mekonen et al. (2010) 24.1% in western Tigray, Ethiopia. Similarly, higher herd level seroprevalence have been recorded by other authors; 62% from Zambia (Samui, Oloya, Munyeme, and Skjerve, 2007), 55.6% from Uganda (Faye, Castel, Lesnoff, Rutabinda, and Dhalwa, 2005) and 43.3% from Ethiopia (Berhe et al., 2007). This difference may be related to overall animal level prevalence status of the disease and numbers of animals pre studied herds (herd size).
Brucellosis in cattle and micro-scale spatial variability of pastoral household income from dairy production in south western Uganda
2017, Acta TropicaCitation Excerpt :The impact of brucellosis on household income was felt in terms of quality and quantity of milk, as well as actual reduction of overall pastoral herd size. The level of brucellosis prevalence in cattle reported in this study was within the range of previously reported cases in several studies conducted in Uganda (Nakavuma and Opuda-Asibo, 1999; Bernard et al., 2005; Nabukenya et al., 2013). The study findings also show spatial disparities in mean prevalence levels of brucellosis and abortions in cattle at a small scale of four km intervals.