Reusing livestock farming wastewater for Tifton 85 irrigation: productivity, morphological, and bromatological indicators

Abstract

The utilization of wastewater from livestock farming (WLF) represents a common agricultural practice, but the absence of research on its agronomic impacts hinders its sustainable implementation. This study assesses the reutilization of WLF combined with nitrogen fertilization on the morphological, bromatological, and productivity attributes of a Tifton 85 pasture during the winter season. The study involved the application of different types of water via sprinkler: (I) stream water; (II) mixture of WLF and stream water at a 1:1 ratio; and (III) undiluted WLF combined with mineral nitrogen fertilization (0 and 45 kg N ha^-1) administered at the commencement of the regrowth period. Irrigation was applied on a weekly basis, totaling 2,440 m³ ha^-1. At 106 days post-regrowth, parameters including forage productivity, height, leaf-stem ratio, leaf area index, nitrogen nutrition index, crude protein content, acid detergent fiber, neutral detergent fiber, and mineral matter content were determined. Mineral fertilization at the prescribed dosage (45 kg N ha^-1) did not have any discernible impact on the parameters under investigation. On average, the reuse of WLF raised the productivity from 2.50 to 5.12 t ha^-1 and the Crude Protein from 12.35% to 14.58% compared to stream water. The reuse of WLF demonstrated superior outcomes (p < 0.01) in terms of pasture productivity, nutritional quality, and nitrogen accumulation compared to irrigation solely with stream water. The reuse of diluted WLF (1:1) without fertilization proved adequate to sustain Tifton 85 pastures during the winter season in the Brazilian Cerrado region.

Keywords: Cynodon dactylon, forage, irrigated pasture.