On-farm evaluation of fodder bank adoption among agropastoralists in northern Nigeria.

摘要

A fodder bank is a field of legume-based forage conserved until the late dry season when livestock experience severe nutritional stress. The purpose of the present study was to conduct an on-farm evaluation of fodder banks of Stylosanthes hamata cv. Verano (stylo) managed by agropastoralists in northern Nigeria. The 30 fodder banks included in the study were spread over six states and across subhumid and semiarid ecological zones. Biological and sociological data were gathered from 1989 to 1991.;Adoption of fodder bank technology promoted by government extension agents has followed a sigmoid growth curve since 1981. A credit package favoring agropastoralists who own land was used to pay for fencing, the major cost of fodder bank establishment. Agropastoralists used fodder banks to maintain old or weak cattle that might otherwise die. Cattle with access to fodder banks experienced less dry-season weight loss than cattle supplemented with cereal brans and native range. Trespassing was identified as the main problem with fodder banks, followed by risk of fire.;Stylo comprised 53% of three-year-old fodder banks, with mean peak air-dry biomass of 3837 kg/ha in the subhumid zone and 2673 kg/ha in the semiarid zone. By mid dry season when fodder banks were ready for utilization, standing biomass had declined (without livestock grazing) to 2227 and 1276 kg/ha, respectively, in the SHZ and SAZ ecozones. Protein content of fodder bank forage fell from 10 to 7% over the same four-month period. Grazing fodder banks in the early growing season and for 5h/day in the late dry season favored stylo seedling establishment and the persistence of perennating plants. Fodder bank improved soil fertility. Yield of maize grown in fodder banks was 71% higher than in adjacent fields, but indigenous sorghum varieties failed to respond to fodder bank or fertilizer treatments.;A feasibility analysis revealed a higher benefit:cost ratio for fodder banks compared to traditional dry season supplementation. Fodder banks were more economically attractive in the subhumid zone than the semiarid zone, and incorporating a maize crop rotation within fodder bank management substantially enhanced return on investment.