Current manure management practices and hygiene aspects of urban and peri-urban livestock farming in Tanzania

A M Lupindu*, H A Ngowi*, A Dalsgaard**, J E Olsen** and P L M Msoffe***

* Department of Veterinary Medicine and Public Health, Sokoine University of agriculture, P.O. Box 3021, Morogoro, Tanzania
** Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Stigbøjlen 4, 1870 Frederiksberg C, Denmark
*** Directorate of Undergraduate Studies, University of Dodoma, P.O. Box 259, Dodoma, Tanzania
amsalale@yahoo.com   ;   alupindu@suanet.ac.tz

Abstract

The recent expansion of urban and peri urban livestock farming has resulted in close contact between animals and humans, sometimes with adverse human health effects. A survey involving 119 cattle keeping households in urban and peri-urban settings of Morogoro,

Tanzania revealed that manure management practices were different from traditional practices mainly due to lack of land. Manure was collected and conveyed by using tools by 94% of respondents, while others used water or bare hands. Seventy six percent of respondents collected manure from animal houses at least once a day, a feature that was associated with housing characteristics (p<0.05). Heaping was a common manure storage method although other cattle keepers directly spread manure on land. Manure was disposed of within residential area by 70% of respondents and this practice was associated with land area owned by or under control of the households (p<0.05). The current manure management practices did not protect either humans, animals or the environment against the risk of contamination with potential zoonotic pathogens and therefore there is a need for the formulation of guidelines on safe manure management practices.

Keywords: environment, hygiene, manure management, peri-urban, urban

Introduction

Manure is largely composed of animal excreta (faeces and urine) that is mixed up with water, beddings and secretions from nose, throat, vagina and mammary glands (Pell 1997). Recovery of pathogenic bacteria in freshly voided animal faeces shows that manure is a potential source of zoonotic pathogens contaminating the environment and represents a risk for further transmission to human (Losinger et al 1997, Pell 1997, Crump et al 2002, Guan and Holley 2003, Johnson et al 2003, Hutchison et al 2004, Hutchison et al 2005, Heuvelink et al 2007). Studies have reported cases of human gastroenteritis due to bacteria enteropathogens of animal origin following consumption of contaminated food or water or direct contact with infected animals in farms (Kapperud et al 2003, Merritt and Herlihy 2003, Hendriksen et al 2004, Smith et al 2004).  

In the last few decades urban and peri-urban farming in developing countries has been progressively increasing. Its emergence and expansion not only came as a survival strategy due to reduced income and living standards (Briggs 1991, Mlozi 1996, 1997a, Mvena 1999, DFID 2002) but also as a diversification strategy to spread livelihood risks in adverse situations (DFID 2002, Simon et al 2004). Some urban and peri-urban dwellers continue to keep livestock to maintain their rural cultural values (Mlozi 1996, Mvena 1999). As a consequence of the increase, both the number of animals kept and the number of households keeping animals has increased. Urban areas of Morogoro, Tanzania, for example had a cattle population of 2,618 in 1996 (URT 1997), which almost doubly increased to 4,170 in 2006 (URT 2007). In 1984 the city of Dar es Salaam urban had 1,763 crossbred dairy cattle (MALD 1988) but by the end of 1993 the cattle population in the urban wards of the city was reported to have increased to 14,721 (Mlozi 1997b). Rapid urban population growth and demand for animal protein has provided a boost to urban and peri-urban farming (Briggs 1991, Simons et al 2004).  

Before the expansion of urban and peri-urban livestock farming, free open grazing practices required minimal effort to manage manure (DFID 2002, Powell et al 1995). Increased animal population has led to an increase in manure production in urban and peri-urban areas and hence a demand for proper handling practices. However, it is currently not known how the manure management practices have changed to adapt to densely populated areas where the space separating humans from animals and their wastes has decreased. Therefore this study aimed at determining the current manure management practices in urban and peri-urban areas of Morogoro region of Tanzania as a basis for developing strategies to improve urban and peri-urban farming practices that safeguard human and animal health. 

Materials and Methods

Study area 

This study was conducted in urban and peri-urban areas of Morogoro region of Tanzania. Morogoro region typifies the relationship between dense urban populations as potential market with expanding urban and peri-urban livestock farming as source of food and income. Three districts of Morogoro region constituted the study area and included Morogoro municipality, Morogoro rural and Mvomero. Morogoro region is located between latitude 5^o 58" and 10^o 0" S and longitude 35^o 25" and 35^o 30" E. Ambient temperature ranges between 18^oC and 30^oC. The annual rainfall ranges between 600 mm – 1200 mm (URT 1997).  

Study design and selection of households for the study 

A cross-sectional survey was conducted from February to September 2010. The study involved 119 cattle keeping households. Participants were selected from a list of 367 cattle keeping households obtained from the District Livestock Development Offices. Simple random sampling of the households was carried out by use of “rank and index” functions in Excel software. This method assigned a unique random number to each of the listed households and selected a required number of households without repetition. Five out of 119 cattle keeping households that withdrew from the investigation were replaced by a random selection of new households within the list of cattle keeping households. 

Data collection and analysis 

Interviews with cattle keepers using semi-structured questionnaires and personal observations using a guide were the main tools to gather information on herd and manure management practices in the selected urban and peri-urban livestock keeping areas of Morogoro. Additionally, face to face interviews with District Livestock Development Officers about herd and manure management practices were carried out. The developed questionnaire aimed at gathering information on (1) herd characteristics and management, taking into account labor division, herd size, presence of animal species other than cattle, type of animal house roofing, floor, feeding system and history of cattle treatment; (2) manure management practices, including means, frequency and form of manure collection, storage, means and distance of manure disposal and household area and (3) awareness on zoonotic enteropathogens. Moreover, the guided interviews with District Livestock Officers from Morogoro Municipality, Morogoro Rural and Mvomero focused on existing guidelines and their monitoring of manure handling practices in their respective areas. Some of the officers produced information materials e.g. “Environmental Sanitation By-Laws” and “Animals in Urban areas By-Laws” that give directives on animal keeping in the areas and how to deal with wastes including manure. 

Data were analyzed using SPSS 15.0 such that means for continuous variables and frequency of occurrence of variable factors for categorical variables were computed. Associations between all possible combinations of categorical variables were analyzed by Pearson’s Chi-square test at significance level of 5%.  

Results

Herd characteristics and management 

From the observation and questionnaire, 119 research participants owned a total of 806 cattle (minimum = 1, maximum = 36, mean= 7, median= 5, SD = 5.85). Among the respondents 95.8% kept animals other than cattle within the same premises including chicken (80.7%), dogs (62.2%), goats (50.4%), pigs (27.7%), ducks (23.5%), cats (21.9%), sheep (10.9%), guinea fowls (9.2%), turkeys (5.9%), guinea pigs (1.7%) rabbits (1.7%) and monkey (0.8%).

It was noted that two different groups of people, namely family members and paid labourers were engaged in management of manure. The proportion of cattle keeping households in the study area that used paid labourers to handle manure and execute other routine farm activities such as feeding cattle, cleaning cattle houses and milking slightly exceeded the proportion in which only family members took care of cattle (Table 1). 

A large proportion of animal houses were roofed, either by thatch grass or corrugated iron sheets compared to the less popular open cattle pens (kraal) (Table 1). In the open cattle pens rainwater wet the soil and animals spent the nights in mud until the sun dries out the soil. This was the case in a few animal houses whose floor was made of earth in contrast to a large percentage of animal houses with concrete floor (Table 1). Only three respondents were observed to put grass on the floor of animal house as bedding material, among them, one had a house with earthed floor (Table 1). All respondents kept their animals in a confinement near to their residential area for security reasons. 

The cattle were fed in different ways with less than half of cattle being kept in-door and fed by a “cut and carry” method, while the others had to move around foraging (Table 1). A relative small fraction of cattle, mostly free range cattle used surface water such as rivers, ponds and wells while most of cattle were provided water from taps also serving the people (Table 1).  

During the night all cattle were kept in enclosures with accumulation of manure. Before discard, manure was collected by bare hands by a few respondents with direct contact to the manure. However, the majority of respondents used utensils such as spades, hand hoes and rakes to collect manure into a pile within the animal house. It was also observed that some respondents used a water hose to collect manure (Table 2). Irrespective of the manure collection method, people did not use any protective measures such as special clothes or gloves and were observed to have direct skin contact with manure. The majority of respondents collected manure at least once a day (Table 2).  

After collection into a heap, manure was moved to storage area either by bare hands or water splash by a small number of respondents while the majority used utensils such as spade, bucket, wheel barrow, plastic bag or raw hide (Table 2). Storage of manure in heaps for sometime before disposal was a common practice among many respondents although it was observed that a few of them directly spread manure from animal houses into the surrounding environment (Table 2). 

Some cattle keepers used manure as fertilizer, especially those owing large piece of land while others did not use manure as fertilizer at all. However, in both cases, most respondents spread manure direct on land as the preferred way of disposal (Table 2). Respondents who did not spread manure on land opted for burning or giving it away to friends in plastic bags. Most cattle keepers disposed the manure either as fertilizer or waste within a radius of 10 m from their residential house (Table 2).   

The use of rubber boots was an observed practice by less than a half of respondents while the remaining fraction wore ordinary shoes e.g. sandals while handling manure (Table 2). There was a tendency for a large proportion of livestock keepers to allow effluent from animal house to spread freely on the surrounding land except for a few respondents who directed the effluent into a pit (Table 2). The size of the area owned and used by households is of interest from hygiene perspective as human and animals shared such land. It was observed that respondents who had more than 1000 m² of land were in large number compared to those living on less land (Table 2)                            

When asked about their knowledge on pathogens associated with manure respondents revealed that they have never heard about such pathogens except for a few respondents who were aware that there could be enteropathogens in manure that may cause enteric diseases (Table 2). 

There were associations between herd characteristics and management and the way that manure was handled. For instance, the type of animal house roof was related to the type of animal house floor such that roofed animal houses had concrete floors while roofless houses had floors made of earth (p<0.001). These animal house characteristics were significantly associated with the frequency of manure collection from the animal houses, i.e. manure was collected at least once a day for roofed animal houses that had a concrete floor (p<0.001). On the other hand, manure storage practice was associated with the size of land under control of the household. Households with an area equal or less than 1000 m² had to keep manure in heaps before disposal whereas respondents with land areas more than 1000 m² spread manure from animal houses directly onto the surrounding land (p=0.015). The source of water for cattle was found to be significantly associated with the type of animal feeding system. Zero grazed cattle were given tap water that was also used by humans while cattle foraging outdoor used surface water such as ponds, river and boreholes (p<0.001). When herd size was transformed into a categorical variable, it was found that herds with more than five cattle were mostly grazing outdoor while herds with five or less cattle were zero grazing (p=0.009).  

Discussion

The diverse manure management practices of the cattle keepers in the study area were determined by customs and convenience. Some farmers said that they handled the manure by the same methods since childhood; others opted for a particular manure management method because it was easy to execute. A number of farmers did not use protective measures and equipment to handle manure because of the associated costs.  The differences in manure management practices and lack of hygienic protective measures among cattle keepers underlines the need for disseminating information on proper handling of animal wastes to guide farmers on safe collection, conveyance, storage and disposal of manure. For instance, according to Morogoro Municipal Council (2002, 2010), manure is regarded as solid waste that is treated like any other household waste, but there does currently not exist any guidelines or regulations on proper manure management in Morogoro region or elsewhere in Tanzania .  

Manure management guidelines in other parts of the world have centred on reduction of environmental pollution, in particular eutrophication of aquatic recipients, and improvement of nutrient availability to crops. Guidelines have so far not addressed the health of personnel who handle manure at farm level or those living in areas with urban livestock. A guideline of manure management in Asia by IAEA (2008) aims at making manure handling easier, decreasing odours and water and air pollution as well as promoting production of biogas and more valuable organic fertilizer. Also manure management guidelines by Ohio State University Extension (2006) and Nova Scotia (2006) inform farmers on how to utilize manure as valuable fertilizer and energy source while at the same time protecting the environment. In general there does not seem to exist guidelines in neighboring African countries that provide livestock keeper’s information on sustainable manure management, in particular for urban livestock keeping. The guidelines developed for Asian, European or American farmers are of little relevance and not addressing the problems and challenges faced by livestock keepers in urban and peri-urban settings of developing countries like Tanzania (Mlozi 1996). 

The current manure management practices seen in Morogoro differ from the way manure was handled a few decades ago. Before urban and peri-urban livestock farming intensified and became more commercial manure management did not require much effort by the farmers. For instance in a neighboring city of Dar es Salaam, animals spent daytime foraging and dropping manure everywhere, while manure accumulated during overnight confinement was left to decompose in house compounds, live hedges or open spaces or thrown in streams or along road sides for it to be washed away by rain or sometimes applied on crop plots (Shauri 1989, Mlozi 1997b, DFID 2002). This practice happened before transition from specialization (free open grazing) to integration (confined zero grazing and crop growing), where by the former did not call for special manure handling practices compared to the later farming system (Powell et al 1995). Reports by Mlozi (1996 and 1997b) revealed that an increased manure production in populated urban and peri-urban areas of Dar es Salaam has led to scarce area for disposal, such that decomposing manure produced odour and favoured breeding of pathogens and flies. These detrimental effects of manure handling practices in urban and peri-urban areas come as a result of land scarcity and poor manure handling infrastructures because urban and peri-urban livestock farming was not integrated in planning process of towns like Morogoro, Dar es salaam, Dodoma and Mbeya (Mvena 1999).  

Animals such as cattle, sheep and goats have been reported as potential reservoir of zoonotic pathogens most of which reside in the gastrointestinal tract and are voided in faeces (Crump et al 2002, Mersha et al 2010, Cobbaut et al 2009). For instance, Kang’ethe et al (2007) isolated E. coli O157:H7 from cattle faeces in urban and peri-urban settings of Nairobi. Cases of human infection by pathogens associated with manure due to either contact with infected animals or consumption of contaminated animal products are common (Germani et al 1997, Crump et al 2002). Manure-associated pathogens may be introduced into different places in the food production chain. Nonga et al (2009) reported thermophilic campylobacter prevalence of 5.6% from faeces of slaughtered cattle, 9.3% of dressed carcases at abattoirs and 1.9% in beef sold in meat shops in the city of Morogoro. Other studies (Hiko et al 2008, Abdul-Raouf et al 1996, Benkerroum et al 2004, Kang’ethe et al 2007) have reported the isolation of a number of pathogens in food products of animal origin. The trend of pathogen contamination seems to build up through the food chain from animal at farm level to food products. It is evident from our results that lack of proper manure handling is associated with quite substantial faecal contamination of the environment and thus putting human and other animals at risk of infection particularly those associated with enteropathogens. Livestock keeping and manure management in peri-urban and urban areas with high densities of animals and humans demands development of guidelines and enforcement of regulations on proper hygienic manure management practices that reduce faecal contamination of the environment and protect human health 

It was shown that a large proportion of respondents were not aware that manure may contain a variety of pathogens hazardous to human and animal health. Similar lack of knowledge was reported by Mlozi (1996) among livestock keepers in urban and peri-urban settings of Dar es Salaam where the farmers had little knowledge about pathogens and associated risks. Thus it is clear that the current manure management practices of cattle keepers in Morogoro region did not aim at preventing any transmission of pathogens between human, cattle and environment or other ways to protect human and animal health. 

The study by Kang’ethe et al (2007) in urban and peri-urban areas of Nairobi reported that manure handling was a risk factor for human infection and pointed out that the use of protective gear during manure handling could reduce the infection risk. Thus it is likely that the cattle keepers in our study area were at increased risk of infection because they neither wore gloves nor protective clothing during manure handling.  Our findings call for further research to document the occurrence of pathogens in cattle manure, occupational health hazards for livestock keepers, their families and others living in peri-urban and urban areas where livestock are kept to establish effective guidelines and regulations that protect human health while at the same time recognizing the socio-economic benefits of urban livestock keeping.   

The association between certain manure management practices and household conditions, as elucidated in this study, could be used to improve manure management practices. Improving the animal house by putting concrete floor and a roof was found important in relation to increasing the frequency of manure collection from the animal house to at least once a day. Additionally, it has been reported by Lekasi et al (2003) and Rufinol et al (2007) that improved animal houses such as that with a roof, concrete floor and good drainage reduce loss of manure and retain higher phosphorus and nitrogen content the same as when manure heaps are covered with polythene films. Therefore, improving animal housing infrastructures may not only ease manure handling workload, but is also likely to protect human, animal and environmental health while retaining the fertilizer value of the manure.

Conclusion

• The current manure management practices differ from those methods employed a few decades ago in both the actual practices and resource base available that is shared by human, animals and manure. Increased manure production in a shrinking space force cattle keepers to collect, convey, store and finally dispose manure. In the course of this process, human and environment are put at risk of pathogen contamination. Therefore there is a need to design manure handling practices that suits the available land resource at the same time safeguarding human, animals and the environment.

Acknowledgment

This study was conducted under the project “Opportunities and Challenges in peri-urban livestock farming in Tanzania” under the collaboration of Sokoine University Agriculture (Tanzania) and University of Copenhagen (Denmark). The authors wish to thank the Ministry of Foreign affairs of Denmark through the Danish International Development Agency (DANIDA) for financial support.   We acknowledge the cooperation from offices of Regional commissioner Morogoro, Mvomero and Morogoro district commissioners, district Executive Directors for Mvomero, Morogoro rural and municipal councils. We acknowledge participation of cattle keeping households and extension staff in urban and peri-urban areas of Morogoro.  

References

Abdul-Raouf U M, Ammar M S and Beuchat L R 1996 Isolation of Escherichia coli 0157:H7 from some Egyptian foods. International Journal of Food Microbiology, volume 29, pages 423-426 

Benkerroum N, Bouhlal Y, El Attar A and Marhaben A 2004 Occurrence of shiga toxin–producing Escherichia coli O157 in selected dairy and meat products marketed in the city of Rabat, Morocco. Journal of Food Protection, volume 67, pages 1234–1237 

Briggs J 1991 The peri-urban zone of Dar es Salaam, Tanzania: Recent trends and changes in Agricultural Land Use. Transactions of the Institute of British Geographers, New Series, volume 16, pages 319-331 Retrieved July 15, 2012 from http://www.jstor.org/discover/10.2307/622951?uid=3739224&uid=2129&uid=2&uid=70&uid=4&sid=21100918203911  

Cobbaut K, Houf K, Buvens G, Habib I and De Zutter L 2009 Occurrence of non-sorbitol fermenting, verocytotoxin-lacking Escherichia coli O157 on cattle farms. Veterinary Microbiology, volume 138, pages 174–178 

Crump J A, Sulka A C, Langer A J, Schaben C, Crielly A C, Gage R, Baysinger M, Moll M, Withers G, Toney D M, Hunter S B, Hoekstra R M, Wong S K, Griffin P M and Van Gilder T J 2002 An outbreak of Escherichia coli O157:H7 infections among visitors to a dairy farm. The New England Journal of Medicine, volume 347, pages 555-560. Retrieved July 15, 2012 from http://www.nejm.org/doi/pdf/10.1056/NEJMoa020524  

(DFDI) Department for International Development 2002 Peri-urban and urban livestock keeping in East Africa: A coping strategy for the poor?  Scoping study commissioned by the Livestock Production Programme (LPP) Page 15 Retrieved July 15, 2012 from http://www.dfid.gov.uk/r4d/PDF/Outputs/ZC0201a.pdf  

Germani Y, Soro B, Vohito M, Morel O and Morvan J 1997 Enterohaemorrhagic Escherichia coli in Central African Republic. Lancet, volume 349, page 1670 Retrieved July 15, 2012 from http://download.thelancet.com/pdfs/journals/lancet/PIIS0140673605626360.pdf  

Guan T Y and Holley R A 2003 Pathogen Survival in Swine Manure Environments and Transmission of Human Enteric Illness: A Review. Journal of Environmental Quality, volume 32, pages 383–392 

Hendriksen S W M, Orsel K, Wagenaar J A, Miko A and Van Duijkeren E 2004 Animal-to-human transmission of Salmonaella Typhimurium DT104A variant. Emerging Infectious Diseases, volume 10, pages 2225–2227 Retrieved July 15, 2012 from http://wwwnc.cdc.gov/eid/article/10/12/pdfs/04-0286.pdf  

Heuvelink A E, Valkenburgh S M, Tilburg J J H C, Van Heerwaarden C, Zwartkruis-Nahuis J T M and De Boer E 2007 Public farms: hygiene and zoonotic agents. Epidemiology and Infection, volume 135, pages 1174–1183 Retrieved July 15, 2012 from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2870684/pdf/S0950268807008072a.pdf  

 Hiko A, Asrat D and Zewde G 2008 Occurrence of Escherichia coli O157:H7 in retail raw meat products in Ethiopia. Journal of Infection in Developing Countries, volume 2, pages  389-393 Retrieved July 16, 2012 from http://www.jidc.org/index.php/journal/article/view/19745509/112  

Hutchison M L, Walters L D, Avery S M, Synge B A and Moore A 2004 Levels of zoonotic agents in British livestock manures. Letters in Applied Microbiology, volume 39, pages 207–214 Retrieved July 16, 2012 from http://onlinelibrary.wiley.com/doi/10.1111/j.1472-765X.2004.01564.x/pdf  

Hutchison M L, Walters L D, Avery S M, Munro F and Moore A 2005 Analyses of Livestock Production, Waste Storage, and Pathogen Levels and Prevalences in Farm Manures. Applied and Environmental Microbiology, volume 71, pages 1231–1236. Retrieved July 16, 2012 from http://aem.asm.org/content/71/3/1231.full.pdf+html  

(IAEA) International Atomic Energy Agency 2008 Guidelines for Sustainable Manure Management in Asian Livestock Production Systems. A publication prepared under the framework of the RCA project on Integrated Approach for Improving Livestock Production Using Indigenous Resources and Conserving the Environment. Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture. Vienna, Austria. Retrieved July 16, 2012 from http://www-pub.iaea.org/MTCD/publications/PDF/TE_1582_web.pdf  

Johnson J Y M, Thomas J E, Graham T A, Townshend I, Byrne J, Selinger L B and Gannon V P J 2003 Prevalence of Escherichia coli O157:H7 and Salmonaella spp. in surface waters of southern Alberta and its relation to manure sources. Canadian Journal of Microbiology, volume 49, pages 326-335 

Kang’ethe E K, Onono J O, MacDermott B and Arimi S M 2007 Isolation of E. coli O157:H7 from milk and cattle faeces from urban dairy farming and non dairy farming neighbour households in Dagoretti Division, Nairobi, Kenya: prevalence and risk factors. East African Medical Journal, volume 84, pages 65-75 

Kapperud G, Espeland G, Wahl E, Walde A, Herikstad H, Gustavsen S, Tveit I, Natås O, Bevanger L and Digranes A 2003 Factors associated with increased and decreased risk of Campylobacter infection: A prospective case-control study in Norway. American Journal of Epidemiology, volume 158, pages  234–242 Retrieved July 16, 2012 from http://aje.oxfordjournals.org/content/158/3/234.full.pdf+html  

Lekasi J K, Tanner J C, Kimani S K and Harris P J C 2003 Cattle manure quality in Maragua District, Central Kenya: effect of management practices and development of simple methods of assessment. Agriculture, Ecosystems and Environment, volume 94, pages  289–298 

Losinger W C, Garber L P, Smith M A, Hurd H S, Biehl L G, Fedorka-Cray P J, Thomas L A and Ferris K 1997 Management and nutritional factors associated with the detection of Salmonella sp. from cattle fecal specimens from feedlot operations in the United States. Preventive Veterinary Medicine, volume 31, pages 231-244 

Merritt T D and Herlihy C 2003 Salmonaella outbreak associated with chicks and ducklings at childcare centres. Medical Journal of Australia , volume 179, pages 63-64 

Mersha1 G, Asrat D, Zewde B M and Kyule M 2010 Occurrence of Escherichia coli O157:H7 in faeces, skin and carcasses from sheep and goats in Ethiopia. Letters in Applied Microbiology, volume 50, pages 71–76 

(MALD) Ministry of Agriculture and Livestock Development 1988 Statistical Abstract of the Livestock Census 1984, Dar es Salaam: In Mlozi M R S 1997b Urban Agriculture: Ethnicity, cattle raising and some environmental implications in the city of Dar es Salaam, Tanzania. African Studies Review, volume 40, pages 1-28 

Mlozi M R S 1996 Urban agriculture in Dar es Salaam: Its contribution to solving the economic crisis and the damage it does to the environment. Development Southern Africa, volume 13, pages 47-65 

Mlozi M R S 1997a Impacts of urban agriculture in Dar es Salaam, Tanzania. The Environmentalist, volume 17, pages 115 -124 

Mlozi M R S 1997b Urban agriculture: Ethnicity, cattle raising and some environmental implications in the city of Dar es Salaam, Tanzania. African Studies Review, volume 40, pages 1-28 

Morogoro Municipal Council 2002 Animals in Urban area (Amendment) By-Laws 

Morogoro Municipal Council 2010 Environmental Sanitation By-Laws 

Mvena Z S K 1999 The Past, Present and Future of Urban Agriculture in Tanzania. Journal of Agricultural Economics and Development, volume 3, pages 71-77. Retrieved from http://www.tzonline.org/pdf/thepastpresentandfutureofurbanagriculture.pdf  on July 17 2012 

Nonga H E, Sells P and Karimuribo E D 2009 Occurrences of thermophilic Campylobacter in cattle slaughtered at Morogoro municipal abattoir, Tanzania. Tropical Animal Health and Production, volume 42, pages 73-78 

Nova Scotia 2006 Manure Management Guidelines. Retrieved July 16, 2012 from http://www.gov.ns.ca/agri/rs/envman/manureguide_2006lowres.pdf  

Ohio State University Extension 2006 Ohio Livestock Manure Management Guide, Ohio State University Extension Bulletin 604. Retrieved July 17, 2012 from http://agcrops.osu.edu/specialists/fertility/fertility-fact-sheets-and-bulletins/bulletin_604.pdf/view  

Pell A N 1997 Manure and Microbes: Public and Animal Health Problem? Journal of dairy Science, volume 80, pages 2673–2681 Retrieved July 16, 2012 from http://lshs.tamu.edu/docs/lshs/end-notes/manure%20and%20microbes_public%20and%20animal%20health%20problem-2713870618/manure%20and%20microbes_public%20and%20animal%20health%20problem.pdf  

Powell J M, Fernández-Rivera S, Williams T O and Renard C 1995 Livestock and Sustainable Nutrient Cycling in Mixed Farming Systems of sub- Saharan Africa. Volume II: Technical Papers. Proceedings of an International Conference held in Addis Ababa, Ethiopia, 22–26 November 1993. ILCA (International Livestock Centre for Africa), Addis Ababa, Ethiopia. Retrieved July 17, 2012 from http://mahider.ilri.org/bitstream/handle/10568/2721/cycling1.pdf?sequence=1  

Rufinol M C, Tittonell P, van Wijk M T, Castellanos-Navarrete A, Delve R J, de Ridder N and Giller K E 2007 Manure as a key resource within smallholder farming systems:Analysing farm-scale nutrient cycling efficiencies with the NUANCES framework. Livestock Science, volume 112, pages 273–287 

Shauri R 1989 Rus in Urbe: A Study of Agricultural Activities in the City of Dar es Salaam. Unpublished Diploma Project Paper. Dar es Salaam, Tanzania: Ardhi Institute. In Mlozi M R S 1997b Urban Agriculture: Ethnicity, Cattle Raising and Some Environmental Implications in the City of Dar es Salaam, Tanzania. African Studies Review, volume 40, pages 1-28 

Simon D, McGregor D and Nsiah-Gyabaah K 2004 The changing urban-rural interface of African cities: definitional issues and an application to Kumasi, Ghana. Environment and Urbanization, volume 16, pages 235-247. Retrieved July 17, 2012 from http://eau.sagepub.com/content/16/2/235.full.pdf+html  

Smith K E, Stanzel S A, Bender J B, Wagstrom E, Soderlund D, Leano F T, Taylor C M, Belle-Isle P A and Danila R 2004 Outbreaks of enteric infections caused by multiple pathogens associated with calves at a farm day camp. Pediatric Infectious Disease Journal, volume 23, pages 1098–1104. Retrieved from http://www.cdc.gov/ncidod/osr/site/eip/pdf/smith-2004-outbreaks%20of%20enteric%20infect%20assoc%20w%20farm%20daycamp.pdf  

(URT) United Republic of Tanzania 1997 Morogoro Region Socio-Economic Profile, Page 67 Retrieved May 13, 2011 from www.tzonline.org/pdf/Morogoro.pdf 

(URT) United Republic of Tanzania 2007 Morogoro Region Socio-Economic Profile, Page 46 Retrieved January 22, 2012 from www.tanzania.go.tz/regions/MOROGORO.pdf

Received 18 July 2012; Accepted 13 August 2012; Published 3 September 2012

Go to top