Productivity and Chemical–Bromatological Composition of Mombaça Grass Fertigated With Cattle Slaughterhouse Effluent With and Without Disinfection With Peracetic Acid

Wastewater from cattle slaughterhouses is a source of nutrients for the fertigation of crops because of the presence of nitrogen and phosphorus. This study aimed to analyze the yield and nutritional composition of Mombaça grass (Panicum maximum) exposed to different doses of cattle slaughter effluent, with and without the addition of the disinfectant peracetic acid (PAA). The experiment was conducted using a completely randomized design, with eight treatments: E100 = 100% effluent; E50:50 = 50% effluent + 50% water; ET50:50 = 50% effluent treated with PAA + 50% water; E75:25 = 75% effluent + 25% water; ET75:25 = 75% effluent treated with PAA + 25% water; E25:75 = 25% effluent + 75% water; ET25:75 = 25% effluent treated with PAA + 75% water; and Control = 100% water, with five replicates each. Chemical and bromatological analyses of Mombaça grass showed that nitrogen, phosphorus, magnesium, and calcium levels increased progressively with an increase in the amount of effluent compared with that in plants irrigated only with water (control group). An increase of crude protein, mineral matter, and total digestible nutrients was observed, along with a reduction in the concentrations of crude fiber and ether extract in the E100 group. Fertigation with bovine effluent contributed to an improvement in the quality of Mombaça grass, mainly due to the increased protein amount and adequate nutrient levels. The application of PAA in the effluent contributed to the reduction of pathogens, but presented fewer benefits for the plant when compared with the effluent without PAA.