**2. Exploration of animals-humans-environment interaction**

and high built-up area with technological and economic advancement. Rural areas, on the other hand, are open broad areas of land located far from towns and cities, which are composed of extensive bushes between large crop fields and livestock herds and sparse housing and population density. Between the urban and rural settings lies peri-urban zone whose population, livestock, crops and land use features are influenced by the proximate interface. Part of peri-urban area adjacent to urban area has features resembling urban features, while its other side assumes the rural characteristics. There is no distinct line separating the peri-urban from urban and rural settings, but a slow zone of change [1]. The gradual transition from peri-urban to urban setup is moving constantly away from city center toward the rural direction due to

Urban and peri-urban livestock farming is expanding in developing countries primarily due to high demand for protein of animal origin to feed the rapidly growing urban populations, but also to generate income of livestock keeping households [2]. It is also a diversification tactic to spread livelihood risks in adverse situations [3]. Some urban and peri-urban dwellers continue to keep livestock to maintain their rural cultural values [4]. The expansion of urban and peri-urban livestock farming, which is reflected as an increase in number of both the livestock and households involved in keeping livestock, and rapid urban human population growth has increased the chance of contact between humans, animals and manure. Urban areas of Morogoro in Tanzania, for example, had a cattle population of 2618 in 1996 [5], which almost doubly increased to 4170 in 2006 [6]. By 2008, the cattle population in Morogoro urban was 19,099, and among them, 4425 were dairy cattle [7]. This cattle population hiked up to 49,625 in 2012 [8]. Rapid urban population growth is primarily caused by influx of people from rural areas either as migrants or as commuters [1, 9]. For instance, Tanzania's annual population growth rate between 1988 and 2002 was 3% with the urban population size increasing from 18% in 1988 to 23% in 2002 [10]. Moreover, population size and growth in rural and urban areas of Morogoro region from 2002 to 2012 show that the rural population grew by 23.7% from 1,279,513 in 2002 to 1,582,434 compared to 34.2% growth in urban population from 473,849 in 2002 to 636,058 in 2012 [8]. In this region, the general population density changed from 24 persons per square kilometer in 2002 to 31 persons per square kilometer in 2012 [11]. As a result of increased human and animal density, the chance of contact between humans and livestock has increased. The growth in animal population and concomitant increase in manure production, in shrinking space separating humans, livestock and manure, require appropriate livestock and manure management practices taking into

Four decades ago, before the expansion of urban and peri-urban livestock farming, free open communal cattle grazing system required minimal effort to manage manure [3, 13]. Cattle freely grazed during daytime and were confined during the night for security. Most manure was left scattered everywhere except for a small amount which was applied on crop fields [3, 14]. To date, the manure management practices have changed to adapt to densely populated areas where the space separating humans from animals and their wastes has decreased. A question arises: does this change consider prevention of animal and human from pathogen exposure as well as environmental contamination? This chapter describes assessment of

persistent urbanization pressure, especially in developing countries.

74 Livestock Science

account that livestock harbors zoonotic pathogens [12].

Most of the people who keep cattle in urban and peri-urban areas also keep other livestock such as goats and chicken. Members of livestock keeping households share premises with livestock. In this community, livestock keeping households are randomly mixed with households which do not keep livestock. There is no tangible demarcation between livestock keeping households and non-livestock keeping households, and hence, the two types of households are in close contact. A total of 119 households keeping cattle, randomly selected, were willingly enrolled for the study in urban and peri-urban areas of Morogoro, Tanzania. Each cattle keeping household was paired to a non-cattle keeping household selected from any direction within a radius of 100 m for purpose of comparison. This pair was regarded as a cluster. Assessment of the interaction between cattle, humans and the environment within and between clusters involved field visits in order to make observations and interview household representatives about livestock and manure management practices. Questionnaire to cattle keeping households inquired about herd characteristics and management, manure management practices, awareness on zoonotic health risks and constraints to livestock farming in urban and peri-urban areas. Observations were made to top up and confirm the information gathered from the questionnaire. Details of labor division, herd composition and size, animal housing and feeding, herd health management, means and frequency of manure collection, storage and disposal were obtained at household level. Questionnaires to non-cattle keeping households enquired about attributes which may contribute to contact between humans, cattle and manure. Moreover, District Livestock Officers were interviewed about monitoring of manure handling practices in their respective areas of jurisdiction and were asked to present documents guiding livestock and manure management. This cross-sectional study was carried out from February 2010 to February 2012.

Cattle feces, human stool, soil and water samples were collected from each participating household for isolation and characterization of bacteria to check for the presence of pathogens and evidence of transmission between cattle, humans and the environment. In this particular study, *Escherichia coli* and non-typhoidal Salmonella spp. were target bacteria. Individual 100–150 g cattle fecal samples were collected by a gloved hand. A 100 g pooled soil sample from each household (cattle keeping and non-cattle keeping households) was obtained by taking 2–5 cm of top soil from five different areas within household premise. From each participating household, 100 ml water sample was collected in 250 ml container from stored water or sources such as boreholes, ponds or river which are used by humans and livestock. Stool sample from one household member was requested. For cattle keeping households, a member involved in cattle and/or manure management was eligible to give stool sample, while for non-cattle keeping households, any member was eligible. On the evening before sample collection day, a stool collection container was given to an appropriate person for collection of stool in the following morning. All samples for a cluster were collected on the same day and immediately placed in an insulated box with cooling elements and transported to the laboratory where bacteriological analysis was initiated.

Ethical clearance was approved by Sokoine University of Agriculture Ethical Committee to handle animals and animal samples. Approval was also obtained from the Tanzania National Institute for Medical Research (NIMR) Ethical Board (NIMR/HQ/R8a/Vol. IX/927) to handle and process human sample. All conditions for research approval were observed throughout the study.
