African Journal of
Agricultural Research

  • Abbreviation: Afr. J. Agric. Res.
  • Language: English
  • ISSN: 1991-637X
  • DOI: 10.5897/AJAR
  • Start Year: 2006
  • Published Articles: 6576

Full Length Research Paper

Effects of cattle and manure management on the nutrient economy of mixed farms in East Africa: A scenario study

Snijders Paul1, Hugo van der Meer2, Davies Onduru3, Peter Ebanyat4, Kebebe Ergano5, Joshua Zake6, Bram Wouters1*, Louis Gachimbi7† and Herman van Keulen2
1Livestock Research, Wageningen University and Research Centre, P.O. Box 65, 8200 AB Lelystad, the Netherlands.   2Agrosystems Research, Plant Research International, Wageningen University and Research Centre, P.O. Box 616, 6700 AP Wageningen, the Netherlands.   3ETC-East Africa, P.O. Box 76378, Nairobi, Kenya.   4School of Agricultural Science, Makerere University, P.O. Box 7062, Kampala, Uganda.   5Debub University, P.O. Box 5, Awassa, Ethiopia.   6Environmental Alert, P.O. Box 11259, Kampala, Uganda.   7Kenya Agricultural Research Institute, P.O. Box 14733, Nairobi, Kenya.
Email: [email protected]

  •  Accepted: 01 February 2013
  •  Published: 24 October 2013

Abstract

This paper explores effects of animal and manure management in a dairy unit on the nutrient economy of crop-livestock farms in East Africa. For this purpose, 8 cattle management scenarios have been developed based on farming systems in Mbeere, Kenya (extensive), Wakiso, Uganda (semi-intensive) and Kibichoi, Kenya (intensive). Three baseline scenarios represent present-day cattle management; five improved scenarios use the same dairy breeds but have improved nutrition, using younger grass, more legumes and moderate amounts of concentrates. These improvements strongly increase milk production per cow, but also N, P and K excretion in manure. The 8 cattle management scenarios are combined with 2 levels of manure management technology: a baseline technology, reflecting actual manure management and related losses of plant nutrients, and an improved technology with lower losses. Nutrient losses for each technology level have been derived from a thorough analysis of published information. This showed that current systems of collection and storage of the excreta of confined dairy cows are associated with large nutrient losses, in particular of N. These losses cause serious deficits on the N, P and K balances of the crop-livestock farms.  Therefore, significant external N, P and K inputs and better manure management are required to sustain the production levels assumed and to avoid further soil fertility depletion in the region. The paper identifies several possibilities for this and concludes that there is a strong need for integral on-farm studies aiming at development of sustainable dairy production systems.

 

    Key words: Dairy systems, manure storage, manure composition, N cycling efficiency, NPK  balances,       soil fertility, Napier grass, legumes, forage quality.