Characterization of Cattle Manure Value Chains in South-Central Vietnam

Abstract Text: Cattle manure value chains play an important role in smallholder crop-livestock systems in south-central Vietnam. Lowland cattle farmers sell manure through a network of chain participants to pepper, coffee, dragon fruit, and rubber farms in the Central Highlands and south coast. This study describes cattle manure value chains originating in two representative lowland communes, Nhơn Khánh (NK) and An Chấn (AC). Semi-structured interviews with value-chain participants between April and September 2013 collected information from lowland farmers (n=101), manure collectors and traders (n=27), rubber companies (n=2), highland farmers (n=50), and dragon fruit farmers (n=20) about cattle management, manure-related labor, manure transactions, and fertilizer and manure use. Lowland cattle owners were selected using stratified random sampling. Farmer interviews identified subsequent value chain participants. Most farmers interviewed reported manure sales (AC=78%, NK=92%), and reported sales of 62% of farm manure with SD ± 26%. Farmers prepared manure for sale by drying it on the ground or in cakes for approximately 4 days. Dry manure (89 ± 3% DM, 18.7 ± 5.6% OM, 1.27 ± 0.37% N, and 0.59 ± 0.27% P₂O₅) was bagged and sold to local manure collectors who arranged transfer to highland farmers, south coast farmers, or traders. Manure was sold by the bag (bag volume in AC = 20.4 L, NK = 46.6 L). Sale price in farmer-reported transactions was $34.19 ± 4.95/m³ in AC and $24.31 ± 3.88/m³in NK. Preliminary analyses suggest annual farmer revenue of $116 ± 102 in AC and $120 ± 93 in NK, thus providing an important source of supplementary income. Manure not sold was composted and used for crop fertilization. Farmers reported most manure sales between February and August (during NK and AC dry season) when demand exists for organic amendments in the highlands. From NK, approximately 80% of manure sold flowed to Gia Lai Province and 20% to Đắk Lắk Province in the Central Highlands. From AC, 70% flowed to Gia Lai, 10% to Đắk Lắk,  and 5% to Đắk Nông. 15% flowed to dragon fruit farmers in Bình Thuận Province late in the year. Prior to application, highland farmers purchasing manure often prepared a 45-day compost with manure and other amendments including potassium, urea, coffee pulp, and a commercial probiotic. This study generated descriptive information about manure value chains in Vietnam that can inform analysis of value chain dynamics via simulation modeling.

Keywords: cattle manure, value chain, Vietnam