Identifying Positive Deviant Farms Using Pareto-Optimality Ranking Technique to Assess Productivity and Livelihood Benefits in Smallholder Dairy Farming under Contrasting Stressful Environments in Tanzania

Abstract

In smallholder dairy-cattle farming, identifying positive deviants that attain outstanding performance can inform targeted improvements in typical, comparable farms under similar environmental stresses. Mostly, positive deviants are identified subjectively, introducing bias and limiting generalisation. The aim of the study was to objectively identify positive deviant farms using the Pareto-optimality ranking technique in a sample of smallholder dairy farms under contrasting stressful environments in Tanzania to test the hypothesis that positive deviant farms that simultaneously outperform typical farms in multiple performance indicators also outperform in yield gap, productivity and livelihood benefits. The selection criteria set five performance indicators: energy balance, disease-incidence density, daily milk yield, age at first calving and calving interval. Findings proved the hypothesis. A few farms (27: 3.4%) emerged as positive deviants, outperforming typical farms in yield gap, productivity and livelihood benefits. The estimated yield gap in typical farms was 76.88% under low-stress environments and 48.04% under high-stress environments. On average, total cash income, gross margins and total benefits in dairy farming were higher in positive deviants than in typical farms in both low- and high-stress environments. These results show that the Pareto-optimality ranking technique applied in a large population objectively identified a few positive deviant farms that attained higher productivity and livelihood benefits in both low- and high-stress environments. However, positive deviants invested more in inputs. With positive deviant farms objectively identified, it is possible to characterise management practices that they deploy differently from typical farms and learn lessons to inform the uptake of best practices and extension messages to be directed to improving dairy management.

Assessing Animal Disease Prevalence and Mortality in Smallholder Dairy Farms under Contrasting Management Practices and Stressful Environments in Tanzania

“…The study builds on positive deviant farms earlier objectively identified in a large sample of farms using Pareto-Optimality ranking technique [18]. The positive deviant farms were isolated on criteria of consistently outperforming (p < 0.05) typical farms in five production performance indicators.…”

“…Specifically, these were total energy balance to indicate the extent that cattle were experiencing feed scarcity, disease incidence density to indicate the extent that animals were exposed to disease infections while daily milk yield, age at first calving and calving interval indicated the extent of expression of production and functional traits. Shija et al [18] have detailed a stepwise process implemented to identify posi-…”

“…One, the temperate/highland ecosystem that has developed around Mount Kilimanjaro is a result of the mountain's high altitude reducing the typically high tropical temperatures. The temperature-humidity index (THI) estimated by Shija et al [18] is within the heat stress threshold (68 to 71) category as defined by Zimbelman et al [19]. Rainfall is of a bimodal pattern, favoring high year-round fodder biomass growth for a mixed rain-fed production system.…”

“…The eastern milkshed in this study is classified as a high-stress dairy production environment. The characteristic features underlying this classification are a combination of high humidity, low altitude and high temperatures with THI within the category of mild to moderate heat stress (72 to 79) levels for dairy cattle [18]. The ecosystem is considered high in incidences and prevalence of tick-borne diseases -East Coast Fever, Babesiosis and Anaplasmosis, and internal parasitic worm infestations.…”

“…Mating is both by a bull and artificial insemination while milking is done twice a day by hand. The milk yield was estimated recently at an average of 8.55 L/d [18], translating to a 305-d lactation milk production of 2600 liters. D. S. Shija et al…”