Assessment of animal manure production, management and utilization in Southern Highlands of Tanzania

H L Jackson and E J Mtengeti

Department of Animal Science and Production, Sokoine University of Agriculture,
PO Box 3004, Morogoro. Tanzania.
jhlema@yahoo.co.uk; emtengeti@yahoo.co.uk

Abstract

A survey was conducted in Njombe district southern highland of Tanzania to assess livestock manure production, management and utilization. Cross section type of survey was used in this study. Structured questionnaires and personal observations were used as tools. A sample of 60 households was randomly selected for interviewing. Data obtained were analysed using Statistical Package for Social Science (SPSS) computer soft ware. Descriptive statistics namely means, frequencies, percentages and cross tabulation were used to determine relationship between variables. Furthermore samples of stored manure from cattle between 3-7 months were collected. Nitrogen (N), phosphorus (P), potassium (K) and organic carbon (C) were determined in the samples of manure.

The study revealed that 80 % of the surveyed household did not get enough manure to fertilize their crop fields. It was noted that majority of farmers (78 %) who kept dairy cattle compost their manure in the barn constructed by wood slabs and covered by thatch grass. Furthermore majority of farmers (90 %) who keep local cattle leave manure in the kraal and add maize stover to increase the amount of manure. Manure composted in the barn was found to have relatively higher N, and K (1.96, 1.75 % DM) than kraal manure (1.13, 0.94 % DM), pit composted manure (1.58, 0.94 % DM) and manure piled outside (1,41, 0.84 % DM).

Key words: Management, manure, quality, southern highlands of Tanzania

Introduction

High potential arable land in the highlands of East Africa provides sustenance to millions of households. With high population density, more than 800 people per Km ² in some areas, there is hence a high demand for food (Lekasi et al 2001). The traditional means of increasing crop production by simply expanding the area under cultivation is not feasible due to increased human population density. Thus there is a shift from extensive to more intensive mixed crop/ livestock farming systems.

Luoga (2002) noted that in some part of southern highlands of Tanzania, mixed farming is commonly practiced. Under this system manure is used as the fertilizer for crops and fodder production and the crop residues and crop by-products are part of the animal feeds. Rafiy (2004) reported that in areas where use of animal manure is already common, efforts should be directed into manure management. When animal manure is left in the open air as most farmers do, it may lose most of its potassium and some of its phosphorus but much of its nitrogen and varying amounts of other nutrients are lost through volatilisation and leaching (Kwakye 1980; Matsumoto et al 1997). Thus effective manure management is required to reduce nutrient losses from manure. Tanner et al (1993) reported that in order to give viable recommendation to farmers, indigenous knowledge and practice should be used as a starting point for scientific intervention. Therefore this paper reports a study on the assessment of farmers' methods of manure production, management and utilization in southern highlands of Tanzania.

Materials and methods

Description of the study area

This study was conducted in Makambako division in Njombe district Southern Highland of Tanzania. The area lies within 1600 to 1800 m above sea level and around 9^° S and 34 ^° 90' E. The area receives an annual rainfall ranging from 1000 to 1600 mm from December and April. Annual temperature range is 12 to 23 ^°C. The soils are rather sandy with low total nitrogen and phosphorus (Mtengeti et al 2003). Nearly all households practice mixed farming system, whereby both crop cultivation (mainly maize, beans and Irish potatoes) and livestock (cattle, sheep and goats) production are predominant. Home garden size ranges between 1 to 2 ha

Survey on manure production, management and utilization in Makambako division

Structured questionnaires and personal observation were used to assess the current manure production, management and utilization. Four villages were surveyed and from each village a simple random sampling was used to select fifteen farmers who practice mixed farming. The villages were Mtwango and Ikelu in Mtwango ward and Ibumila and Kichiwa in Igongolo ward. The information obtained from this survey includes number of livestock owned by households, livestock feeding systems, methods of manure handling, and priority of manure use and limitation of manure utilization

Manure sampling and analysis

Samples of stored manure from local and dairy cattle between 3 and 7 months were collected. In this period manure was considered by farmers to be ready for utilization as fertilizer for crop production. Sampling of manure was done according to Zhang (2001) by scooping from four random spots on the manure heap to a depth of about 30 cm. The four samples were mixed together and representative sub-samples of approximately 0.25 kg were  taken and stored in a plastic bag. The manure samples were kept in a cool box with ice cubes during transportation and then stored in a deep-freezer before analysis of N, P and K.

Chemical analysis of manure

Total nitrogen of manure was determined by the micro Kjeldahl digestion (using 0.5g fresh manure sample), distillation and titration method (Juo 1979). Total phosphorus and potassium were determined by dry ashing method as described by Juo (1979). Organic carbon was determined by Walkley- Black method (Juo 1979). The dry matter content of the manure was obtained by oven drying a sub-sample at 105 ^oC for 24 hrs. Carbon -Nitrogen ratio was computed by dividing the amount of carbon to that of nitrogen. Calculations were made on dry matter basis.

Data analysis

Data obtained in the survey were analysed using SPSS computer software. Descriptive statistics namely means, frequencies, percentages and cross tabulation were used to determine relationships between variables. Means and standard deviation were computed for data of nutrient composition of manure.

Results and discussion

General characteristics of livestock farming in the study area

The mean number of dairy cattle per household was 2.7 and 1.8 at Igongolo ward and Mtwango ward respectively (Table 1). The small head ownership of dairy cattle could be due to limited land for production of enough forage as a result of high human population density. Crossbred dairy cattle produce 4 to 5 kg DM manure daily whereas local cattle produce 2 to 2.5 kg DM manure daily (Raussen 1997; Fernandez-Rivera et al 1995). The recommended amount of fertilizer in Njombe is 60 kg N/ha for maize production (NDC 1999). Based on these data and nitrogen content in the indoor composted manure (1.96 % DM) and kraal manure (1.13 % DM) (Table 5), it was observed that in order for a household to produce enough manure to supply N requirement for the 2 ha owned by majority of farmers (43.3 %) in the study area for maize production, a household should have 4 heads of crossbred dairy cattle or 8 head of local cattle. This finding therefore, confirms the report by Palm et al (1997) that with an average of two heads of cattle per household, farmers are likely to produce 2 to 3 tonnes DM of manure per year, that is adequate to meet requirement of one ha of maize crop. However, due to high human population density in the area, there is a land shortage that would not allow the production of forage in enough quantities to feed 4 or more animals. Therefore combining manure and inorganic fertilizer is the best option for the sustainability of crop production in the area.

Livestock feeding systems

The dairy cattle are normally zero-grazed and fed mainly natural forages and crop residues (Table 2). Feed concentrate is only given to the dairy cattle. This finding was also observed by Msangi and Kavana (2002) who reported that natural pastures species in the communally owned land were the major source of food for ruminant animals in Tanzania. Local cattle and goats are only on free range grazing and pigs are fed mainly house waste and a little maize brain. Feeding systems of local cattle and goats through free grazing results in a loss of 60 -70 % of the manure (Schleich 1986). Thus manure that can be recovered for use in the crop field is only 30-40 %.

Use of beddings and manure collection from the animal barn

Majority of households (91 %) keeping local cattle applied bedding in the kraal (Table 3). This was a reflection of the importance of manure production in the area since it was done in the dry season, possibly so as to increase the amount of manure for the subsequent cropping season. Use of beddings preserves a lot of urine nitrogen in the manure (Raussen 1997). However, since the kraal is left open there are substantial losses of nutrients through volatilisation and leaching (Kichman 1985; Murwira 1995). On the other hand, 67 % of the households keeping dairy cattle were not applying bedding. This was due to the presence of concrete floors in the animal barn. Eighty four percent of dairy cattle farmers remove manure from the animal barn daily. This is because HPI (Heifer Project International) gave them animals with a condition that they should clean the animal barn every day. It was also observed that majority of local cattle keepers (60.6 %) remove manure from the kraal once a year. The removal of manure from local cattle kraal once a year in southern highlands of Tanzania was also reported in Mbinga (IARMW 1998). Majority of farmers (81.7 %) had knowledge on the importance of urine as a fertilizer. Thus 71.7 % of the households use bedding or constructed concrete chambers besides the animal barn to capture urine.

Manure handling techniques and utilization

Composting manure in the barn was practiced by 78.4 % of the dairy cattle keepers in the study area (Table 4). The manure barn was constructed with wood slab walls with thatched roof. The barn had 4 - 5 cubicles, whereby fresh manure was piled in the first cubicle and after one month turned to the next cubical and to the next in the coming months until the 4^th cubicle and thereafter stored in the 5^th cubicle ready to be applied to the crop field. Most of the dairy farmers (78.4 %) are composting manure in the barn that may mean it is more beneficial over other methods. According to Muller-Samann and Kotschi (1994) farmers tend to accept innovations only when they offer them a clear visible improvement or benefit. Local cattle keepers leave manure in the kraal for six months or one year. Probably due to larger herd with no restriction of cleanliness of the kraal. According to Rynk (2004), 4 to 6 months are enough time to reflect the benefits from composted manure, especially moisture loss and destruction of weed seeds.

Fifty-eight percent of the respondents utilize most of their manure on maize plots. This was in agreement with the observation of Hawassi (1997) that most of the farmers in Southern Highlands of Tanzania utilize the greater part of their manure in maize production. This could be due to the importance of the maize crop in food security and high economic return. In order of their priority 80 %, 38 %, and 30 % of the respondents identified inadequate amount of manure, high labour required during manure application and transport of manure to the field as major limitations of manure utilization. Inadequate amount of manure to farmers was also reported by Lekasi et al (2001). This is due to the high application rate and low nutrient levels in organic fertilizers as compared to inorganic fertilizer. Also Defoer et al (1998) reported that factors such as the distance of the crop fields from homestead, available means of transport and labour, influence the extent of manure utilization. Despite the advance in use of draught power in the area, transport of manure to the field was identified as one of the problems of manure utilization. This may be due to the high demand of draught animals for ploughing that coincide with season of manure application.

Effect of different handling techniques on the quality of stored cattle manure

Manure composted in the barn had relatively higher nitrogen and potassium than kraal or in the earth pit (Table 5).

This findings was contrary to what was reported by Kwakye (1980) and Nzuma et al (1998) where pit method of composting was superior to surface composting. The pits in this study area were not cemented and some farmers did not cover their pits, thus a lot of nutrients might have been lost through leaching and volatilization. Indoor-composted manure had the lowest C/N ratio while kraal manure had the highest C/N ratio. Maize crop residues that were used as beddings in the kraal could be the reason for this high C/N ratio. Njoroge (1994) reported a C/N ratio in maize stalks ranging from 50 to 150. Such high values of C/N ratio could influence the C/N ratio of the manure when maize stalks are used as bedding.

Conclusions

• The study revealed that the majority of the households did not get enough manure to fertilize the crop fields.

• Majority of farmers who keep dairy cattle composted their manure in the barn while most of those keeping local cattle left the manure inthe kraal until it was sent to the crop field.

• Manure composted in the barn was found to have relatively higher nutrients than outdoor composted and kraal manure especially in terms of nitrogen and potassium contents.

• The study has shown that the major limitations of manure utilization were inadequate amount manure

Acknowledgment

The authors wishes to extend warmest gratitude to all who have supported the research and development work in this study particularly the Japan International Cooperation Agency (JICA) and SUA Center for Sustainable Rural Development (SCSRD)

References

Defoer T, Bubelman A, Toulmin C, Carter S and Ticheler J 1998 Soil Fertility Management in Africa. Resource Guide For participatory learning and Action Research part 1. pp 1-59.

Fernandez-Rivera S, Willium T O, Hiernax P and Powell M 1995 Faecal excretion by ruminant and manure availability for crop production in semi-arid West Africa. In: Livestock and Sustainable Nutrient cycling in Mixed Framing systems of Sub-Saharan Africa. Volume II: Technical Papers. Proceeding of an International Conference held in Addis Ababa, Ethiopia , 22-26 November 1993 (Editors Powell J M, Fernandez-Rivera S, Williams T O and Renard C). ILCA (International Livestock Centre for Africa Addis Ababa, Ethiopia,pp 149 - 169

Hawassi F G H 1997 Effect of fertilizer subsidy removal on fertilizer use and maize production in Mbinga district. Unpublished Dissertation for award of MSc degree at Sokoine University of Agriculture, Morogoro Tanzania, pp 50-80.

IARMW 1998. Integrated Agro-ecological Research of the Miombo Woodlands in Tanzania, Final report, pp 413

Juo A S R 1979 Methods of Plant and Soil Analysis. Manual Series No.1.International institute for Tropical Agriculuture, Ibadan, Nigeria, 65pp.

Kichman H 1985 Losses, plant uptake and utilization of manure nitrogen during production cycle. Acta Agricultural Scandinavia, 24: 76 - 92

Kwakye P K 1980 The effects of method of dung storage and its nutrient (NPK) content and crop yield in the northeast Savanna zone of Ghana. In: Organic Recycling in Africa. FAO 1980. Soil Bulletin No. 43: 282-288

Lekasi J K, Tanner J C, Kimani S K and Harris P J C 2001 Manure Management in the Kenya Highlands. Practices and Potential, Second edition. Emmersons, Farmer Ward Road, Kenilworth, UK. 35pp

Luoga T 2002 Assessment of the quantity and quality of feed resource for dairy cattle animals in the low plains of Makambako division in Njombe District. Unpublished Special Report for award of BSc. Degree at Sokoine University of Agriculture, Morogoro, Tanzania, pp 18-23

Matsumoto T, Noshiro M and Hojito M 1997 The Effect of Farm Yard Manure of Different Degradation levels on Grass Production.In: Plant Nutrition for Sustainable Food Production and Environvement (Edited by Ando T, Fujita K, MaeT, Matsumoto,H, Mori S and Sekiya J) Kluwer Academic publisher, Japan.pp591-592.

Msangi B S J and Kavana P Y 2002 Survey and evaluation of grasses and legumes for feeding dairy cattle in Morogoro and Kibaha district. In: Proceedings of the 1^st collaborative research workshop on food security (Editors Batamuzi E K and Tarimo A J P). 28-30 May 2002. TARPII - SUA Project. Morogoro. pp 163 - 167

Mtengeti, E J, Urio N A, Pereka A E, Magne Mo, Mgasa M N, Phiri E J, Mbwile R A and Ayo E 2003. Performance of selected MPTs under smallholder dairy farmers'home garden plots in Njombe district, Southern Highlands of Tanzania. In: Proceedings of the 2^nd collaborative research workshop on food security (Editors Batamuzi E K and Tarimo A J P). 28-30 May 2003. TARPII - SUA Project. Morogoro. pp 246-251

Muller-Samann K.M and Kotsch J P 1994 Sustaining Growth: Soil fertility management in Tropical Smallholdings.Margraf Verrlag. Germany. 460pp

Murwira HK 1995 Ammonia volatilisation from Zimbabwe cattle manure before and after application to soil. Tropical Agriculture (Trinidad) 72:267 - 274

NDC 1999 Njombe District Council. Annual report.Njombe.10pp Njoroge W J 1994 Field Notes on Organic Farming. KIOF, Kenya. 17 - 24 pp

Njoroge WJ 1994 Field Notes on Organic Farming. KIOF, Kenya. pp 17 - 24  

Nzuma J K, Murwira H K and Mpepereki J 1998 Cattle manure management options for reducing nutrient losses. Farmer perception and solutions in Mgwanda, Zimbabwe. In: The soil fertility research for maize-based systems in Malawi and Zimbabwe (Editors Waddington S R, Murwira H K, Kumwenda J P K, Hikwa D and Tangwira F) CIMMYT pp 183-190

Palm C A, Myers R J K and Nandwa S M 1997 Combined Use of Organic and Inorganic Nutrient Sources for Soil Fertility maintenance and Replenishment. In: Replenishing Soil Fertility in Africa (Edited by Buresh J R, Sanchez P A and Calhoun) Madison, Wisconsin, USA pp 193-217

Rafiy S 2004 Management and utilization of animal manure as resources for crop production under two major grazing systems in Tanzania. [http: www.developmentgateway.org] site visited on 23/7/2004.

Raussen T 1997 Integrated soil Fertilizer management on small-scale farms in eastern province of Zambia. English press Ltd.Nairobi, Kenya. 87pp

Reijntjes C, Haverkrot B and Waters-Bayer A 1992 Farming for future. An introduction to low input and sustainable Agriculture. Macmillan press. London , 300pp.

Rynk B M 2004. Compost: Education and Resources for Western Agriculture. (http://www.aste.usu.edu/compost/index.htm) Site visited 13/05/2004

Schleich K 1986 The use of cattle dung in agriculture. Natural Resources and Resource Development. 23: 53 - 87

Tanner J C, Holden S J, Winugroho M, Owen E and Gill M 1993 Feeding Livestock for composite Production: A strategy for sustainable upland agriculture on Java. In: Livestock and Sustainable Nutrient cycling in Mixed Framing systems of Sub-Saharan Africa. Volume II: Technical Papers. Proceedings of an International Conference held in Addis Ababa, Ethiopia , 22-26 November 1993 (Editors: Powell J M, Fernandez-Rivera S, Williams T O and Renard C). ILCA (International Livestock Centre for Africa Addis Ababa, Ethiopia,pp115-128.

Zhang H, Hamilton DW and Britton J G 2001 Sampling animal manure. Oklahoma, University press, USA. 70pp. http://www.soiltesting.okstate.edu/Extn_Pub/F-2248web.pdf