Bacterial and parasitic zoonoses encountered at slaughter in Maiduguri abattoir , Northeastern Nigeria

An abattoir survey to determine the prevalence of zoonotic diseases encountered at postmortem examination of organs and carcasses was conducted in Maiduguri municipality, Nigeria, between 2000 and 2009. A total of 1,378,066 animals were examined and slaughtered from which 403,560 were cattle, 381,601 goats, 373,567 sheep and 219,308 camels. Out of these numbers, a total of 14,944 bacterial and parasitic zoonotic diseases were diagnosed which included tuberculosis (67.6%), dermatophilosis (15.8%), mange (16.7%), fascioliasis (1.5%) and hydatidosis (4.3%). Occurrence of the diseases based on sex, species of animals and season of the year did not show any significant difference (P>0.05). It was not possible to get the exact records on breed and age for each slaughtered animal due to poor recording systems at the abattoir. With regards to the type of animals brought for slaughter, almost all animals come from the traditional sector and it was difficult to precisely trace back the geographical origins of all animals slaughtered due to lack of reliable animal identification method and so relating the finding of the study to a particular locality becomes difficult. Species-specific prevalence of tuberculosis was 1.6%, 0.4%, 0.3%, 0.3% for cattle, sheep, goats and camels respectively with a 0.7% crude prevalence. Analysis of the tuberculosis cases showed a high rate of occurrence in cattle (P<0.05) and the most affected organs were the lungs (55.1%) and associated lymph nodes (27.7%) (P<0.05). It was concluded that zoonotic diseases such as tuberculosis, dermatophilosis and mange are endemic in the study area. Abattoir records are invaluable in epidemiological surveillance and other aspects of disease control and prevention strategies.


Introduction
the fight against malnutrition and unemployment in the urban and rural areas of the world (Tanya et al., Nigeria has the largest number of livestock 2004).population in the West African sub-region and about High prevalence of animal diseases affects both 11.6% of the livestock population are in sub-Saharan health and productivity of livestock population.As a Africa (FAO, 2000).The country has a livestock result of devastating outcome of livestock diseases, population of about 16.3 million cattle, 40.8 million animal protein output has not been able to keep up with goats, 27 million sheep, and 151 million poultry the nation's demands (Njombe and Msanga, 2009).(http://www.africanagricultureblog.com/2007/12/nig Increasing demand for meat and meat product by eria-has-16-million-cattle.html).Livestock and human population has made human contact with poultry production are the main economic activities of animals unprecedented, coupled with movement of about 70% of Nigerians living in rural and urban areas.animals across international frontiers to supplement There is increasing contact between humans and the local supply and increasing the risk of zoonotic animals worldwide due to rising population density diseases especially from endemic zones (Shcwabe, and growth especially in developing countries where 1984).livestock offers important socio-economic, cultural The control of livestock diseases still remains a and religious pathways out of poverty (WHO, 2004).problem because of inadequacy of veterinary services However, food animal production has become a extended to livestock owners particularly those in the rural areas (Kambarage et al., 1995).This may strategic subsector for diversification of income and contribute to a widespread prevalence of diseases in Qualified veterinarians serve as meat inspectors under traditional sector (Mellau et al., 2010).Some livestock the supervision of Veterinary Surgeon as officer in owners dispose sick, debilitated and infertile animals charge.Records of total number of cattle, sheep, goats and camels brought for slaughter, antemortem and in an effort to minimize losses.Such animals postmortem examination records of lesions were sometimes are brought to the abattoir for slaughter retrieved from Maiduguri abattoir record books.Such while some are slaughtered elsewhere.In developing records were used to establish the prevalence of countries, abattoirs and slaughter slabs have poor meat bacterial and parasitic zoonotic diseases and lesions inspection facilities and shortage of qualified meat affecting cattle, sheep, goats, and camels.Routinely, inspectors (Edwards et al., 1997;Biu et al., 2006) and meat inspectors carry out antemortem examinations of may serve as focal points for disease dissemination.
all animals presented for slaughter a day before or The slaughterhouse and its regulations, represents a shortly prior to slaughter.This is followed by key control point of livestock production chain (
by a bacterium in the genus Mycobacterium spp.

Materials and methods
which pathologically is characterized by tubercule formation in the lungs and associated lymph nodes.(Mbaya et al., 2008).The state has a total area of congolensis.The condition is sometimes referred to as 72,609 sq.km and is the largest of 36 states in Nigeria "rain scald" as it often looks like raindrops have just in terms of landmass and has a human population of fallen on the skin.The condition is initially seen as 4,151,193 based on 2006 census (NBS, 2011).The pustules that are often over-looked.However, the state has a total Gross Domestic Product (GDP) of pustules quickly come to together to form large oval about US$5.18 billion and a per capita income of crusts as the longer hairs become stuck together in the US$1,214.The state is bordered by three francophone scab.These large crusty scabs are easily seen.Thick, countries namely Niger, Chad and Cameroon creamy pus can be found under active crusts.When the (https://www.cgidd.com/Geography-Selection.aspx).scabs or crusts are removed, the underlying skin is Borno State has a relatively short rainy season starting usually hollowed out and often bleeds.Most animals in June and ending in October, and a longer dry season do not appear to have itching sensation, however, the with the harmattan starting in November and ending in lesions are painful when the scab is manipulated.The February.The average monthly temperature of most common locations of the lesions in cattle are 0 rump, topline, udder and teats as well as the belly.Maiduguri is 35 C, however, during the cooler periods (November-February) the average temperature drops Mange is a persistent contagious skin disease of 0 mammals caused by a tissue-burrowing arthropod, the to about 20 C (http://www.climate-charts.com/mange mite causing a lot of skin irritation and itching.Locations/n/NI65082.php).
Hydatidosis or echinococcosis is a parasitic

Data retrieval, collation and procedures:
The infection caused by the larvae of a microscopic Maiduguri central abattoir was selected for the study and is under the supervision of Ministry of Animal and tapeworm of genus Echinococcus.Fascioliasis is an infectious disease caused by Fasciola parasites, which are flat worms referred to as liver flukes.The adult (mature) flukes are found in the bile ducts and liver of infected people and animals, such as sheep and cattle.In general, fascioliasis is more common in livestock and other animals than in On the basis of seasonality, more cases were people.
recorded in the raining season than the dry and cold Data analysis : The data for this study were analyzed harmattan seasons as seen in Table 3 but not using simple descriptive statistics in excel spreadstatistically significant (P>0.05).Detailed analysis of sheet.Categorized variables were computed and the tuberculosis cases are shown in Table 4 with cattle, further compared using Chi-square test at critical goats, sheep and camels having prevalences of 1.6%, probability of P<0.05.The strength of associations 0.25%, 0.4%, and 0.33% respectively.Organ-specific between dependent and independent variables was prevalence of tuberculosis in the slaughtered animals determined using 2 x 2 contingency tables.The variables showed that the lungs and associated lymph nodes compared included prevalence of the diseases based were affected more significantly than the other organs on years, species of animal, sex and season.Organas shown in Table 5. Prevalence of tuberculosis specific prevalences of tuberculosis lesions were also between cattle and other species varied significantly compared.
but not across the years.been diagnosed in man in New York, and surveillance Analysis of the sex prevalence of the diseases did is necessary to establish the zoonotic status of the show that, generally, males were affected more than infection in Nigeria.The organism requires existing the females but not statistically significant, likewise in skin lesions to establish infection, so people with skin terms of disease specificity, males were affected more lesions are at higher risk especially herdsmen, farmers, but not significantly.Such difference may occur by veterinarians and butchers who make direct contact chance or may be due to difference in genetic makeup with infected animals (Ikpeze, 2004). in terms of sexual predisposition.Blood et al. (2007) Fascioliasis which is caused by the trematode has earlier reported higher prevalence of tuberculosis Fasciola spp.constitute both economic and public among female cattle than their male counterparts.health constrains to profitable ruminant production in Seasonality did not have much influence on the outcome of the study even though more cases were tropical Africa (Fabiyi and Adeleye, 1982).Values with superscript along the column do not differ significantly (P>0.05)Values with different superscript along the column differ significantly (P<0.05) Fascioliasis affects the liver leading to liver tuberculosis is the respiratory system and associated condemnation in slaughtered animals.The overall lymph nodes.This is in concordance with the reports prevalence in this study was 1.5% which is lower than of Igbokwe et al. (2001) and Liebana et al. (2008).those reported by Njoku-Tony and Okoli (2011) (Cassidy, 2008).Fasami (1979).Differences in prevalence of Trend of the occurrence of tuberculosis among the fascioliasis may arise due to poor meat inspection different animal species in this study showed a rising facilities and uncooperative attitudes of butchers and falling pattern which suggests that tuberculosis because of lack of compensation of condemned among animal populations in this part of the world is organs, seasonality and differences in geographical still endemic.Endemic nature of zoonotic diseases in locations in relation to the bionomics of their snail the area of study could be due to the lack of proper intermediate host (Anosike et al., 2001).Hydatidosis management of animals against important zoonotic diseases, failure to adopt the test and slaughter policy is a parasitic zoonotic disease caused by the in Nigeria and the influx of infected animals from metacestode stage of the dog tapeworm Echinococcus neighboring countries due to the porosity of our spp.A prevalence of 4.3% in this study was higher borders (Aliyu et al., 2009).when compared with the 0.1% reported by Tijjani et al. (2010) in small ruminants in the same region.

Hydatidosis is associated with livestock morbidity and
The prevalence of zoonotic diseases such as mortality, organ and meat condemnation at inspection tuberculosis, dermatophilosis, mange, fascioliasis and and threat to public health as a result of the close hydatidosis contribute to organ condemnation association between dogs, food animals and man.associated with economic loss.Results of this study Detailed analysis of tuberculosis among the reveals that these diseases are endemic in the study slaughtered animals shows that cattle had the overall area.Retrospective study of diseases encountered at highest prevalence rate of 1.6% which is significantly abattoir will provide useful pathology profiles which different from those of the other animal species in the could be useful in future risk assessment and planning study.The prevalence across the years was not significant.Prevalence of tuberculosis among animal of control and prevention strategies.It is therefore slaughtered in abattoir has been reported by many recommended that retraining of abattoir staff on authors.The overall prevalence of tuberculosis in this modern methods of meat inspection practices be done.
This suggests a need for a rigorous meat inspection study is 0.7%.Higher prevalence rate of 4 Values with different superscript along the column differ significantly (P<0.05) , Even though not a novel finding per se, the affirmation Abebe et al. (2010), Swai and Ulicky (2009), Kithuka of such detail is important in the overall context of et al. (2002), Okoli et al. (2000) and Alonge and disease surveillance and monitoring

The study area: The
study was carried out in The disease can be spread hematogenously to other Maiduguri, the capital and largest urban center in organs of the body.

-2. Occurrence of the diseases based on
The term hydatid Forest Resources of the Borno State Government.refers to the characteristic multicystic lesion a large, Permission was obtained from the relevant authority.roughly spherical, hollow cyst filled with fluid that occurs after infection.It affects both humans and other total of 14,944 bacterial and parasitic zoonotic mammals, such as sheep, dogs, rodents and horses.diseases were encountered which comprised of 9,509 There are three different forms of echinococcosis, cases of tuberculosis (67.6%), 2,217 dermatophilosis (15.8%), 2,345 cases of mange (16.7%), 644 cases of each of which is caused by the larval stages of different hydatidosis (4.3%) and 229 cases of fascioliasis species of the tapeworm of genus Echinococcus.(1.5%) with tuberculosis occurring more significantly These are the cystic echinococcosis also known as than others (P<0.05).Fascioliasis was encountered unilocular echinococcosis), which is caused by mainly in cattles while hydatidosis was encountered Echinococcus granulosus.The second is alveolar majorly in the other animal species under echinococcosis (also known as alveolar colloid of the consideration.The sex-specific prevalence of the liver, alveolar hydatid disease, alveolococcosis, zoonotic diseases encountered is shown in Table 2. multilocular echinococcosis, "small fox tapeworm"), which is caused by Echinococcus multilocularis and Tablethe third is polycystic echinococcosis (also known as sex human polycystic hydatid disease), which is caused by Echinococcus vogeli.

Table 1 .
The trend of tuberculosis The result showed that a

Table - 4. Prevalence of tuberculosis lesions among animals slaughtered at the Maiduguri abattoir from 2000-2009.
.05% was et al. procedure to minimize the chance of consumers reported by Aliyu (2009) from cattle in six acquiring infection through contact with and/or northern states of Nigeria; 3.4% by Opara (2005) from et al. consumption of infected meat.Proper record keeping cattle in Akwa Ibom state; 9% by Maho (1999) from cattle in Chad.Lower prevalence rates of 0.01% of abattoir data and if possible computerization of such and 0.08% were also reported by Alawa et al. (2011) data is necessary.Public enlightenment campaigns on and Ojo (1996) respectively in Zaria.Organ specific good livestock husbandry practices at local and prevalence of tuberculosis did showed that the lungs national levels should be encouraged.were mostly affected (P<0.05) as compared to the Percentage